fMRI: Connectivity & Networks

Hall D                                   Wednesday 13:30-15:30                                                                                                                                       

13:30         3595.     Correlation Modulation Networks to Assess Changes in Functional Connectivity with Task Difficulty

Computer 51

Mayuresh S. Korgaonkar1, Susan Fiore1, Candice J. Perkins1, Nancy K. Squires1, Zengmin Yan1, Mark E. Wagshul1

1Stony Brook University, Stony Brook, New York, USA

Correlation modulation network analyses allow the evaluation of condition specific functional interactions between brain regions. Our previous results show that there is differential recruitment of brain regions in a task difficulty modulated verb generation task. Using the correlation modulation approach, we sought to evaluate the following: 1. If the connectivity between language regions is modulated by experimental conditions – particularly between generating verbs as compared to passive viewing of non-words and difficult as compared to easy to generate verbs; and 2. How these condition-specific modulations of connectivity differ between young and old subjects.

 

14:00         3596.     Effect of Hemodynamic Spatial Variability on Granger-Based Long Term Causality

Computer 51

Gopikrishna Deshpande1, George Andrew James1, Xiaoping Hu1

1Georgia Institute of Technology and Emory University, Atlanta, Georgia, USA

Causal relationships between cortical regions can be inferred from fMRI using Granger causality (GC). However, GC may be affected by spatial variability of the hemodynamic response (HRF). We examine the effect of HRF variability on the causal influences in a neural network that evolves slower than the HRF variability and TR. Simulations showed that the HRF variability leads to erroneous results. Furthermore, we show that the true causality could be recovered by using summary measures derived from the BOLD data instead of the raw fMRI time series. These findings are illustrated using data obtained from a fatigue motor task.

 

14:30         3597.     Network Reduction for Interpreting Large Scale Brain Networks

Computer 51

Gopikrishna Deshpande1, Randall Stilla, Krish Sathian, Xiaoping Hu1

1Georgia Institute of Technology and Emory University, Atlanta, Georgia, USA

In this work, we illustrate the utility of multivariate Granger causality analysis for characterizing large brain networks and introduce a new procedure for removing unimportant nodes while retaining the important ones in the network. This method was applied to tactile perception fMRI data which demonstrated the co-existence of top-down and bottom-up mechanisms in tactile perception.

 

15:00         3598.     Localization of the Language Network Using Resting State Functional Connectivity MRI and Diffusion Tensor Tracking

Computer 51

Joshua S. Shimony1, Adrian A. Epstein1, S Neil Vaishnavi1, Mark W. Sansbury1, Jeff G. Ojemann2, Abraham Z. Snyder1, Marcus E. Raichle1

1Washington University School of Medicine, St. Louis, Missouri, USA; 2University of Washington School of Medicine, Seattle, Washington, USA

Although the language network is localized around the left sylvian fissure in a great majority of the population, there is a significant amount of variability in localization between individuals.  Localization in individuals is of great interest for pre-surgical planning to help decrease the morbidity from left temporal lobe surgery.  The purpose of this project was to study the variability of the language network in individuals and to validate its localization by correlating the results using a functional method, resting state functional connectivity MRI, and an anatomic method, diffusion tensor tracking.

 

13:30         3599.     Discrepencies Between Functional Connectivity Measured with BOLD and CBF in Major Depressive Disorder

Computer 52

Richard Cameron Craddock1, Christopher B. Glielmi2, Paul E. Holtzheimer3, Xiaoping P. Hu2, Helen S. Mayberg

1Georgia Tech, Atlanta, Georgia, USA; 2Georgia Tech and Emory University, Atlanta, Georgia, USA; 3Emory University, Atlanta, USA

Functional connectivity was compared between CBF and BOLD for networks associated with depression.  Overall there was consensus with striking differences.

 

14:00         3600.     Spatially Independent Component Analysis for Automatically Delineating Brain Functional Connectivity with Resting-State FcMRI

Computer 52

Quan Zhu1, Chung-Yi Yang2, Eldom Toh3, John H. Gilmore3, Weili Lin3

1Duke University, Durham, North Carolina, USA; 2National Taiwan University Hospital, Taiwan; 3University of North Carolina at Chapel Hill, Chapel Hill, USA

In this work, automatic procedures were developed to determine the components that most likely reflect brain functional connectivity for resting-state fMRI images using spatial independent component analysis (sICA).   The developed approaches were then utilized to depict cortical connectivity in neonates (2-4wks), one-year and two-year old children.

 

14:30         3601.     Detecting Direct and Indirect Functional Connections Using Granger Causality

Computer 52

Zhenyu Zhou1,2, Yonghong Chen1, Guojun He1, Paul Wright1, Mingzhou Ding1, Yijun Liu1

1University of Florida, Gainesville, USA; 2Southeast University, Nanjing, People's Republic of China

An analysis approach that based on the Granger causality method is proposed to study the directional effective influence between brain regions in fMRI data. Granger causality was employed to extracted BOLD signals to investigate effective connectivity in the brain network. Data from an emotion task were used to validate this method, and the emotion pathway was clarified illustrated focus on the right amygdala. The presented results, exploring directional influences between activated brain regions, indicated that the Granger causality mapping combined with  principal component analysis could improve existing applications of traditional pairwise Granger causality mapping method in human brain  connectivity studies.

 

15:00         3602.     A Comparison of the Abilities of Structural Equation Modeling, Autoregressive Analysis, and Granger Causality to Detect Path Weight Differences in Effect Connectivity Results Calculated from Real FMRI Time Series Data [Not Available]

Computer 52

Suzanne Theisen Witt1, M Elizabeth Meyerand1

1University of Wisconsin, Madison, Wisconsin, USA

Structural equation modeling (SEM), autoregressive analysis (AR), and Granger causality (GC) are three commonly used methods for calculating effective connectivity from fMRI data.  A comparison of these methods’ abilities to detect differences in path weights between two different simple motor tasks is presented.  The results of the comparison suggest that, although the path weights estimated using SEM exhibit a much larger dynamic range than those obtained using AR and GC, these latter two methods may be as good or better than SEM at detecting path weight differences.

 

13:30         3603.     The Effects of Time Length on Resting-State Functional Connectivity

Computer 53

Jun Xie1, Gao-Hong Wu1, Shi-Jiang Li1

1Medical college of Wisconsin, Milwaukee, USA

In this study, we investigated the effects of time length on resting-state functional connectivity. EPI data were acquired at 3T in 10 resting normal subjects. The patterns of motor cortex connectivity were compared using different scan time lengths. Our data suggest that about 400 second scanning provides the best tradeoff between the quality of connectivity map and scan time.

 

14:00         3604.     Spatiotemporal Dynamics of Low Frequency Fluctuations in BOLD FMRI of Rats

Computer 53

Waqas Majeed1, Matthew Magnuson1, Shella Keilholz1

1Georgia Institute of Technology / Emory University, Atlanta, Georgia, USA

This abstract presents:

 

1) Spatial patterns evolving over time in low frequency BOLD fluctuations in rat cerebral cortex

 

2)Preliminary classification of these fluctuations into different 'states'

 

14:30         3605.     Measuring Connectivity in Sensory Cortex Using an FMRI Adaptation Paradigm

Computer 53

Laura M. Parkes1, Rishma Vidyasagar1, Stephen Folger2

1University of Liverpool, Liverpool, UK; 2Elon University, USA

fMRI adaptation paradigms probe neural activity on a millisecond timescale. We investigate whether this approach can be developed to measure ‘connectivity’ between two regions in the somatosensory cortex. Paired vibrotactile pulses are given to digits 2 and 4 at intervals of 50, 200 and 400ms. A reduction in BOLD amplitude is seen in all subjects at 200ms compared to 50ms and 400ms. This could be due to the first pulse inhibiting neighbouring regions, reducing excitability, and so reducing the response to the second pulse. This demonstrates a method of directly measuring the influence and timing of interactions between sensory regions.

 

15:00         3606.     The Anatomical Basis of Rest Functional MRI

Computer 53

Aviv Mezer1, Yossi Yovel1, ofer Pasternak1, Tali Gorfine1, yaniv assaf1

1Tel Aviv University, Tel Aviv, Israel

Basal activity measured with fMRI raised tremendous interest among neuroscientists since functional brain activity could be retrieved while the subject rests (resting state fMRI). We show here that the basis of the resting-state fMRI signal – the blood oxygenation level dependent (BOLD) contrast – has a strong anatomical basis in addition to its functional components. We found high similarity between the clusters of the repeated BOLD measures and atlas segmentation. We suggest that multi-dimensional brain MRI acquisition can be used for parcellation of the brain into regions that could not be extracted with conventional MRI.

 

fMRI: ICA & Clustering Analysis

Hall D                                   Wednesday 13:30-15:30                                                                                                                                       

13:30         3607.     Independent Vector Analysis for Group FMRI Processing

Computer 54

Jong-Hwan Lee1, Matthew Marzelli1, Ferenc A. Jolesz1, Seung-Schik Yoo1

1Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA

We propose to develop an independent vector analysis (IVA) scheme to address the permutation problem of the conventional ICA-based group processing scheme. IVA operates to increase independence across output vector components while maintaining dependence among scalar elements within each output vector component (i.e. across frequency bins within the same output index). The ¡®dependence¡¯ in group fMRI processing is analogous to mutual/similar activation patterns across subjects, which are comparable to the group trend in activation.

 

14:00         3608.     A Method for Group Difference Enhancement by Constraining Mixing Coefficients of ICA Framework

Computer 54

Jing Sui1, Vince Calhoun1,2

1The Mind Research Network, Albuquerque, USA; 2University of New Mexico, Albuquerque, USA

We proposed a novel algorithm called CCICA (constrained coefficient ICA) by incorporating prior statistical group information as constraint into the general ICA framework. Our algorithm improved the capability for identifying the independent component showing the largest group difference related to the mixing coefficients. Applications to both hybrid and real fMRI data demonstrate that CCICA is a promising method for identification of components that can best distinguish schizophrenia patients and healthy controls, and further, it may be more sensitive for extracting features that can serve as potential brain imaging biomarkers of disease.

 

14:30         3609.     Assessing Reliability of ICA Estimates by Resampling and Clustering

Computer 54

Radu Mutihac1

1University of Bucharest, Bucharest, Romania

Analysis of artificially generated fMRI-like data drawn from a single-shot gradient-echo MR EPI block-based visual stimulation paradigm was performed by the stochastic neuromorphic extended Infomax algorithm implementing spatial independent component analysis (sICA). Reliability assessment of the results was carried out by resampling-based techniques and clustering. Fourier and wavelet transforms, which contain weak implicit models of temporal noise, and whitening, which is driven by an explicit noise model, were employed to resampling and setting the appropriate thresholds. Variance estimate that is highly correlated with the separation error was used as model selection criterion for optimizing the parameters of the sICA algorithm.

 

15:00         3610.     fMRI Clustering Based on Connectivity Profiles

Computer 54

samuel emeriau1,2, Fabien Giersky3, Laurent Pierot3, Eric Bittar1

1Université de Reims Champagne-Ardennes, Reims, France; 2Philips Systèmes Médicaux, Suresnes, France; 3University Hospital of Reims, Reims, France

fMRI clustering based on connectivity profiles offers two major advantages in comparison with the classical clustering method: it allows dealing with the problem of spatial correlation of noise that can lead to bad mergings in functional domain and it allows defining a new functional dimension exclusively based on the data without taking the paradigm into account trough specified regressors. The resulting clusters form a partition of the data in homogeneous regions according to both spatial and functional connectivity points of view.

 

fMRI: Mechanisms

Hall D                                   Thursday 13:30-15:30                                                                                                                                           

13:30         3611.     Investigating the Source of BOLD Nonlinearity

Computer 53

Nanyin Zhang1, Xiao-Hong Zhu1, Wei Chen1

1University of Minnesota, Minneapolis, Minnesota, USA

The nonlinear effects in BOLD signal have posed a serious problem in rapid ER fMRI designs. To solve this problem, detailed investigation of the source of BOLD nonlinearity is essential. However, little effort has been spent in separating the potential source of neuronal activity attributing to the nonlinearity observed in BOLD data. The obscurity in this issue seriously impedes accurate modeling of BOLD nonlinearity. Therefore, to find the originality of the BOLD nonlinearity, we have employed a paired-stimulus paradigm in absence of neuronal refractoriness and measured the corresponding BOLD responses. The results indicate that the BOLD nonlinearity can completely be vascular origin.

 

14:00         3612.     Transient and Steady-State Components of the FMRI BOLD Signal in Somatosensory Cortex

Computer 53

Michael Marxen1, Tara L. Dawson1, Fred Tam1, Simon J. Graham1,2

1Baycrest Centre for Geriatric Care, Toronto, Canada; 2University of Toronto, Toronto, Canada

Previous MEG studies have demonstrated transient and steady-state evoked reponses to vibrational touch stimuli to a finger with spatially separated dipole locations in primary somatosensory cortex. The goal of this study is to extract transient and steady state components from the fMRI BOLD response to repeated vibrational stimuli of different durations. In the first three subjects of an ongoing larger study, we found differences in the transient and steady-state activation maps that may reflect transiently and continuously firing neuronal populations. A paired comparison with MEG transient and steady-state dipole locations is in progress.

 

14:30         3613.     Steady-State to Transient Change of CMRO2: Dynamic Calibrated FMRI at 11.7T

Computer 53

Basavaraju Ganganna Sanganahalli1, Peter Herman1, Fahmeed Hyder1

1Yale University, New Haven, Connecticut, USA

We studied the relationship between fMRI BOLD, evoked CBF and the electrical activity of neuronal origin. The BOLD, CBF, CBV and LFP were examined in experiments where the number of the stimuli (2mA, 0.3ms) at rat forepaw was increased from one to four with varying inter pulse interval (IPI) of (167ms, 333ms, 666ms). We found variable dependencies of each measured component (BOLD, CBF, CBV, LFP) with IPI. We found that CMR O2 contributed to BOLD even with IPI of less than 200 ms (i.e., 6 Hz). These results suggest that BOLD at high field (of 11.7T) has sensitivity to reveal a significant CMRO2 component for extremely short events

 

15:00         3614.     Assessment of the Significance of Temporal Delays in the BOLD Signal Response to a CO2 Stimulus

Computer 53

julien poublanc1, Jay Shou Han2, Danny Michael Mandell1, Jeffrey A. Stainsby3, Joseph A. Fisher4, David J. Mikulis1, Adrian P. Crawley1

1Toronto Western Hospital, Toronto, Canada; 2Toronto General Hospital, Toronto, Canada; 3GE Healthcare, Toronto, Canada; 4Toronto General Hospital , Toronto, Canada

Cerebrovascular reactivity imaging combines BOLD MRI with inhaled CO2 to measure brain’s autoregulatory capacity.  Although the magnitude of the BOLD signal is primarily employed to assess reactivity, the temporal delay of the BOLD response contains useful information, investigated in this study.  We calculated a time delay parameter that significantly correlates with the reactivity parameter, as well as with the time to minimum of the dynamic susceptibility contrast images.  We have also observed that the main time delay  occurs not on onset of hypercapnia but arises from a late return to baseline after the ETpCO2 has already decreased.

 

13:30         3615.     Quantifying the FMRI BOLD Signal to Characterize the Event-Related Electrophysiological Response

Computer 54

Zhongming Liu1, Bin He1

1University of Minnesota, Minneapolis, Minnesota, USA

In the present theoretical study, we establish a linkage between the quantified BOLD effect size and  the event-related electrophysiological response. Based upon an assumed linear neurovascular coupling, the BOLD effect size at each voxel can be explicitly interpreted as proportional to the time integral of the power of the event-related local synaptic current flow. This relationship contributes to a more rigorous theoretical framework for fusing fMRI and EEG/MEG, which leads to an advanced high-resolution multimodal neuroimaging technique.

 

14:00         3616.     Towards a Quantitative Relationship Between the BOLD Signal and Deoxyhemoglobin Measured by Near-Infrared Spectroscopy

Computer 54

Dharmesh R. Tailor, MD, PhD1, Yu Chen, PhD, Ravinder Reddy, PhD

1University of Pennsylvania, Philadelphia, Pennsylvania, USA

A quantitative relationship is established between the gradient-echo and the spin-echo based BOLD signal and the deoxyhemoglobin concentration measured by near-infrared spectroscopy in the rat brain. This approach provides a more direct means of calibrating the BOLD signal using the recently proposed hyperoxia approach. Furthermore, spin-echo based methods are shown to be sensitive not only to dissolved oxygen but also to deoxyhemoglobin directly. Additionally, spin-echo based T1?-weighted imaging in demonstrated in humans to yield detectable signal changes due to a change in fraction of inspired oxygen.

 

14:30         3617.     Baseline Cerebral Blood Flow Modulates Functional Perfusion Activation Maps But Not BOLD Activation Maps

Computer 54

Joy Liau1, Joanna Perthen1, Thomas T. Liu1

1University of California at San Diego, La Jolla, California , USA

This study examines the dependence of functional perfusion or cerebral blood flow (CBF) and BOLD activation maps on baseline CBF.  We used a caffeine dose (200mg) to reduce the baseline CBF and found concurrent decreases in the activation map area based on the CBF response but not the BOLD response.  Also, measures of baseline CBF accounted for a significant portion of the inter-subject variability in CBF activation map area. Factors that can modulate baseline CBF, such as age, medication, and disease, should therefore be carefully considered in the interpretation of studies that use functional CBF activation maps.

 

15:00         3618.     Strong Correlation of Spin-Echo BOLD Signal with Neuronal Activity in Rat Cortex During Forepaw Stimulation

Computer 54

Ikuhiro Kida1, Toru Yamamoto1

1Hokkaido University, Sapporo, Japan

The relation between signal in neuroimaging techniques and the neuronal activity is essential to investigate brain function. However, the correlation of the BOLD signals with neuronal activity is still unclear. We investigated whether the spin-echo (SE) BOLD signal correlates with neuronal activities during rat forepaw stimulation with various stimulus currents and frequencies (0.5-2.0 mA and 1-10 Hz). We found that the SE-BOLD signal linearly increases with the integration of somatosensory evoked potential amplitude for all stimulus conditions. This result indicates that the SE-BOLD signals may elucidate the neural activity quantitatively.

 

fMRI: Multimodal & Single Trial

Hall D                                   Thursday 13:30-15:30                                                                                                                                           

13:30         3619.     Retrospective Synchronization (Resync) Avoids the Residual MRI Gradient Artefact in EEG-MRI Experiments

Computer 55

Hendrik Mandelkow1, Pascal Halder2, Daniel Brandeis2, Peter Boesiger1

1University and ETH Zurich, Zurich, Switzerland; 2University of Zurich, Zurich, Switzerland

We present a new software synchronization method which improves the post- processing of EEG-fMRI data for the purpose of removing the notorious MRI gradient artefact. Furthermore, we propose a new procedure for quantifying and comparing the cleaning performance of different post-processing algorithms for EEG-fMRI data. The comparison based on in-vivo data as well as simulations of the MGA at high bandwidth shows that the retrospective synchronisation algorithm can improve or even replace hardware synchronisation as well as other post- processing methods such as slice timing correction and PCA. 

 

14:00         3620.     Comparison of SQUID and MR Detection for Weak Magnetic Fields

Computer 55

Martyn Paley1, Eugeny Krjukov1, LiSze Chow1

1University of Sheffield, Sheffield, UK

This study compares the sensitivity of a single channel SQUID and a 3T MRI system using phantoms and investigates axonal bursts in the median nerve using transcutaneous electrical nerve stimulation (TENS) stimulation using the SQUID.

 

14:30         3621.     Simultaneous FMRI/CBV and EEG During Spike-Wave Seizures in WAG/Rij Rats

Computer 55

Asht Mangal Mishra1, Damien John Ellens, Ulrich Schridde,12, Joshua Ethan Motelow1, Michael J. Purcaro1, Fahmeed Hyder1, Hal Blumenfeld1

1Yale University School of Medicine, New Haven, Connecticut, USA; 2YMPI for Biological Cybernetics, Tübingen, Germany

In absence and other generalized seizure disorders, an abnormal electrical activity termed as spike-wave discharges (SWD) is observed by EEG. fMRI during SWD in humans and animal absence epilepsy models show both increases and decreases in BOLD signals. Here we show regional BOLD increases/decreases during SWD accompanied by CBV increases/decreases in nearly the same areas for anesthetized WAG/Rij rats. Further work will be needed to determine if regions of BOLD decreases during SWD represent vascular steal, a primary neuronal mechanism, or a defect in neurovascular coupling. These findings will be important for the interpretation of various fMRI signals in human absence epilepsy.

 

15:00         3622.     Simultaneous Single Unit and BOLD FMRI Recordings

Computer 55

D Aksenov1, Limin Li1, G Iordanescu1, Alice M. Wyrwicz1

1ENH Research Institute, Evanston, Illinois, USA

Brain hemodynamic functional signal and the corresponding neuronal activity are recorded in an awake, behaving rabbit at high fields.

 

13:30         3623.     Detection of Single-Trial Events in BOLD FMRI Without Prior Stimulus Information

Computer 56

Cesar Caballero1, Natalia Petridou1, Sue Francis1, Ian Dryden1, Li Bai1, Penny Gowland1

1University of Nottingham, Nottingham, UK

The aim of this work is to map in space and time the brain’s response to single stimuli without prior knowledge of stimulus timing. Detection of single-trial events in BOLD fMRI time series is a challenge especially in the presence of physiological and systematic fluctuations. Here, a procedure based on Wiener deconvolution is proposed to detect single-trial events with no prior information on stimuli timing. Automatic detection is carried out only assuming a general shape for the hemodynamic response function, and employing tissue-dependent noise characterization. This technique allowed identification of individual trials, and the spatiotemporal evolution of the BOLD response.

 

14:00         3624.     Increased Statistical Power of in Event-Related Real-Time FMRI (ErfMRI) Using Individual Hemodynamic Response Functions: First Results at 3T and 7T

Computer 56

Maurice Hollmann1, Tobias Moench1, Sebastian Baecke1, Michael Luchtmann1, Claus Tempelmann1, Joerg Stadler2, Johannes Bernarding1

1University of Magdeburg, Magdeburg, Germany; 2Leibniz Institute for Neurobiology, Magdeburg, Germany

Assumptions about the hemodynamic response function (HRF) are used as basis in many fMRI analysis methods. However, the variability of the HRF between subjects, and intra-subject between different brain regions may reduce the statistical power if this assumptions are improper. Acquiring more data to counteract this effect is generally not feasible in real-time fMRI. We analyzed the functional data in event-related real-time fMRI with individual region-based HRF estimates acquired during the experiment-session prior to the main measurement. Using individual HRF estimates instead of the SPM canonical HRF led to an improvement in the statistical significance by an average of 25%.

 

14:30         3625.     Effects of High Field MR Scanner on Simultaneous EEG Data Quality for Single-Trial Discrimination

Computer 56

Cheng-Yu Wei1, Robin I. Goldman1, Paul Sajda1, Truman R. Brown1

1Columbia University, New York, New York, USA

The emerging technology of recording simultaneous EEG/fMRI allows direct measuring and comparison of brain responses to stimuli. Being able to follow changes in attention, adaptation or habituation on a single trial basis by using single trial EEG data to reveal brain regions which correlate with variations in these should considerably advance our understanding of cognitive processing. The simultaneously recorded EEG at 3T, examined with power spectrum analysis were of high quality to allow these single-trial investigations. Quality Assurance tests confirmed that fMRI data, in terms of spatial and temporal SNR, was acceptably stable across time to carry out brain functional studies.

 

15:00         3626.     A Model Phantom for Investigating Concurrent EEG/fMRI

Computer 56

Gerða Björk Geirsdóttir1, Matthew J. Brookes1, Karen J. Mullinger1, Winston X. Yan1, Peter Morris1, Richard W. Bowtell1

1University of Nottingham, Nottingham, UK

Simultaneous EEG/fMRI is a technique that makes functional imaging with high spatiotemporal resolution possible.  However, artefacts induced in EEG recordings by the MR scanner make this challenging. The use of an EEG phantom to conduct simultaneous EEG/fMRI experiments provides a means for validating and improving artefact correction techniques, and for investigating possible sources of the observed artefacts.  Here, two different types of saline loaded agar phantoms are described, a dipole phantom which enables measurements of signals with a specific time-course, and a flow phantom with an added aqueduct designed specifically to mimic blood flow.

 

Bone

Hall D                                   Monday 14:00-16:00                                                                                                                                             

14:00         3627.     Advantages of Isotropic Voxel Size for Classification of Trabecular Bone Struts and Plates in Micro-MR Images

Computer 56

Branimir Vasilic1, Jeremy Magland1, Michael Wald1, Felix W. Wehrli1

1University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA

A new method, based on local inertial anisotropy, has recently been introduced to classify trabecular elements into rods and plates. It relies on a locally calculated tensor of inertia to estimate the class (rod/plate) to which each voxel in the image belongs as well as the orientation of the corresponding rod or plate. While the structure of trabecular bone is anisotropic and can be used to justify the use of high-resolution imaging with an anisotropic voxel size, we show here that images acquired with isotropic voxel size have advantages in faithfully representing the underlying structure of trabecular bone.

 

14:30         3628.     On-Line Prospective Registration of Trabecular Bone MR Images for Longitudinal Examinations

Computer 56

Chamith S. Rajapakse1, Jeremy Magland1, Felix W. Wehrli1

1University of Pennsylvania School of Medicine, Philadelphia, USA

In micro-MRI studies of trabecular bone designed to evaluate structural changes in response to therapeutic intervention, follow-up scan volumes do not typically align with the baseline data due to inaccuracies in patient positioning and scan prescription. These limitations can be overcome by incorporating prospective registration into the acquisition protocol. The technique is based on registering 3D localizer images, acquired prior to the high-resolution images, on-site with an algorithm relying on maximizing the correlation between baseline and follow-up localizers. In phantom and human subject studies it is shown that prospective registration yields very close matching between baseline and follow-up imaging volumes.

 

15:00         3629.     Proton NMR Study of Transverse Relaxation of Rabbit and Rat Cortical Bone

Computer 56

Henry H. Ong1, Suzanne L. Wehrli2, Felix W. Wehrli1

1University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA; 2NMR Core Facility, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA

The NMR signal from cortical bone results from protons in collagen as well as water in the Haversian system. Characterizing transverse relaxation behavior may provide insight into bone composition and architecture. Here, we calculated T2* and T2 components of rabbit and rat cortical bone specimens from bi-exponential fits of FIDs and CPMG signal decays. Both species showed a similar short T2* component arising from collagen. The rat showed a larger short T2 fraction, suggesting a smaller fraction of Haversian canals compared with rabbit. The majority of the bone signal is comprised of water with T2* and T2 values of 200-400us.

 

15:30         3630.     Density, Structure and Texture Quantitation of Bone Trabeculae at 3.0 Tesla

Computer 56

Gary Paul Liney1, Clare P. Bernard1, Chris M. Langton, Lindsay W. Turnbull1

1University of Hull, Hull, UK

1) To validate the use of bone volume fraction (BVF) derived from MRI as a surrogate measure of volumetric density. 2) To investigate the structural and textural relationships of bone trabeculae. 3) To compare imaging coils and sequences in terms of their ability to demonstrate these relationships in clinically relevant protocols, and to obtain an optimised protocol for in vivo acquisitions.

 

14:00         3631.     A Distance Weighted Directional Gradient Method for Fully Automatic Bone Segmentation of Knee MRI

Computer 57

Feng Huang1, Xiaoming Chen2, Deliang Ye1, Sarah Hertel3

1Invivo Corporation, Gainesville, Florida, USA; 2University of Florida, Gainesville, Florida, USA; 3Invivo Corporation, Pewaukee, Wisconsin, USA

Fully automatic knee segmentation is desired since it is both time- and cost-efficient. The widely adopted Chan-Vese (CV) model could be used to implement a fully automatic segmentation technique. However, direct application of CV model on knee segmentation has a difficulty in separating different bones (Femur, Tibia and Patella) since these bones have similar intensity level. In this study, a distance weighted directional gradient method is proposed to automatically separate these bones, and define masks for further bone segmentation. With this technique, different bones can be isolated and fully automatic bone segmentation can be achieved without using any prior shape information.  The proposed method was tested on 14 data sets of knee MRI. Results show that the proposed location detection technique can always provide accurate bone locations.

 

14:30         3632.     Accuracy in Trabecular Bone Structural Measurement from High-Resolution Images Acquired with GRAPPA-Based Parallel Imaging

Computer 57

Ben Hyun1, Suchandrima Banerjee1,2, Sharmila Majumdar1,2

1University of California, San Francisco, San Francisco, California , USA; 2University of California, Berkeley, Berkeley, California , USA

High-resolution magnetic resonance images of the distal radius were acquired to assess the accuracy of bone micro-architecture measurements using GRAPPA-based parallel imaging. Unaccelerated and accelerated images were acquired then analyzed using 2D histomorphometric based analysis to assess image fidelity and reproducibility.

 

15:00         3633.     Comparison of Mechanical Properties of Trabecular Bone Derived from μMRI and μCT

Computer 57

Chamith S. Rajapakse1, Jeremy Magland1, Suzanne L. Wehrli, X Henry Zhang2, X Sherry Liu2, X Ed Guo2, Felix W. Wehrli1

1University of Pennsyslvania School of Medicine, Philadelphia, USA; 2Columbia University, New York, USA

Studies have shown that prediction of bone strength can be improved by including structural properties in the analysis in addition to bone density. The aim of this work was to address to what extent mechanical properties of trabecular bone (TB), measured in terms of Young’s and shear moduli, derived from μMRI, compare with those obtained by μCT at high resolution. To answer this question TB samples were imaged using μMRI and μCT. The data indicate that mechanical constants correlate well between the two modalities and the correlation can be improved by correcting for the bone volume fraction mismatch between them.

 

15:30         3634.     Investigation of Subchondral Bone Cysts and Cartilage Defects Using in vivo 9.4T MRI in a Model of Osteoarthritis

Computer 57

David D. McErlain1,2, Joe S. Gati,2, Vasek Pitelka,2, Jeffrey Mason,2, Rob Bartha,2, David W. Holdsworth,2

1Robarts Research Institute, London, Canada; 2The University of Western Ontario, London, Canada

The main purpose of this study was to use high-field MRI, combined with micro-computed tomography, to assess the various bone and cartilage abnormalities associated with a rodent model of Osteoarthritis.  The use of pre-clinical models allows for the testing of future pharmacological interventions to treat Osteoarthritis.  The benefit of using this technology allows us to scan live rats repeatedly, over 4 week intervals, in less than an hour per session.

From these images, we have quantified the loss of cartilage within the knee joint, as well as the appearance of subchondral bone cysts, after the rat undergoes surgical destabilization.

 

 

Spine

Hall D                                   Monday 14:00-16:00                                                                                                                                             

14:00         3635.     Comparison of Lumbar Artery Anatomy and Degenerative Disc Disease in Healthy Controls and Patients with Low Back Pain Combination of Dynamic, Contrast Enhanced Perfusion and MR-Angiogram in the Lumbar Spine Using a 3Tesla MRI

Computer 58

Shadfar Bahri1, L. Tugan Muftuler1, Hon J. Yu1, Min- Ying Su1, Jamshid Tehranzadeh1, Anton Hasso1, Orhan Nalcioglu1, Vance Gardner2

1University of California, Irvine, USA; 2Orthopaedic Education and Research Institute of Southern California, Orange, USA

This study investigates the feasibility of a lumbar MRA and vertebral body-perfusion in a single examination. Since the lumbar arterial anatomy has not fully been investigated in vivo so far, the role of the segmental arteries in perfusion of the vertebral body and ultimately delivery of nutrients to the avascular disc is of interest. 31 Healthy controls and patients with back pain have been scanned and the segmental arteries and discs were graded. The control group (8) all showed healthy discs and normal arterial anatomy. The patient group (23) showed 22/23 (94.7%) unhealthy discs and 13/23 (56.5%) stenotic or occluded segmental arteries.

 

14:30         3636.     Apparent Diffusion Coefficient and Fractional Anisotropy in the Vertebral Bone Marrow [Not Available]

Computer 58

Yu Ueda1, Tosiaki Miyati1, Naoki Ohno1, Yuko Motono1, Asuka Kouhara1, Masaki Hara2, Yuta Shibamoto2, Harumasa Kasai2, Miyuki Asahi2

1Kanazawa University, Kanazawa, Japan; 2Nagoya City University Hospital, Nagoya, Japan

To assess the state of cancellous tissue, we analyzed ADC and fractional anisotropy (FA) in the vertebral bone marrow using single shot diffusion echo planar imaging. A strong negative correlation was found between ADC and DXA-BMD below moderate marrow fat fraction. Significant correlation was noted between ADC and fat fraction. There was a positive correlation between FA and DXA-BMD, and no correlation between FA and FF in the vertebral bone marrow. In conclusion, diffusion analyses with ADC and FA make it possible to obtain more detailed information of the structure of cancellous tissue and the bone metabolism.

 

15:00         3637.     Mapping Bone Marrow Composition in the Lumbar Spine at 3.0 Tesla

Computer 58

Gary Paul Liney1, Clare P. Bernard1, Chris M. Langton, David J. Manton1, Lindsay W. Turnbull1

1University of Hull, Hull, UK

1) To compare data from two quantitative fat imaging methodologies acquired in the lumbar spine. 2) To map the inter-vertebral and age related variations in fat fraction at high spatial resolution. 3) To assess the relationship between volumetric density and marrow content.

 

                                              Monday 14:00-16:00                                                                                                                                             

15:30         3638.     MR Spectroscopy in Intervertebral Disc -- A Feasibility Study

Computer 58

Jin Zuo1, Azucena Rodriguez1, Xiaojuan Li1, Thomas Link1, Jeffrey C. Lotz1, Sharmila Majumdar1

1Univ. of California, San Francisco, San Francisco, California , USA

Intervertebral disc degeneration usually begins with biochemical changes within the disc. Quantifying the concentration of the metabolites in the discs would provide objective and important information that is associated with disc degeneration. In this study, the non-invasive single voxel MR spectroscopy was used to assess the concentration of metabolites in intervertebral disc on cadaveric discs. The peak height ratios of the metabolite was correlated with the Pfirrmann grading scheme. In addition, a preliminary in vivo human study was conducted.

 

Ultra-Short TE MRI in Musculoskeletal Imaging

Hall D                                   Tuesday 13:30-15:30                                                                                                                                             

13:30         3639.     Ultrashort TE (UTE) Imaging with Off-Resonance Saturation: Creating High Contrast for Short T2 Tissues

Computer 56

Jiang Du1, Atsushi Takahashi2, Christine B. Chung1, Graeme M. Bydder1

1University of California, San Diego, San Diego, California , USA; 2GE Healthcare Technologies, Menlo Park, California , USA

The human body contains a variety of short T2 tissues, including cortical and trabecular bone, tendon, ligaments, etc. Magnetization from these tissues can not be spatially encoded between excitation and acquisition before the signal has completely decayed. These short T2 tissues have a much broader absorption lineshape than the long T2 tissues, making them more sensitive to an appropriately placed off-resonance irradiation. Here we present a technique which combines ultrashort TE (UTE) acquisition with magnetization transfer effect to directly image short T2 tissues with high signal and contrast on a clinical 3T scanner.

 

14:00         3640.     Quantitative Characterization of the Connective Tissues of the Fingers in Cadaveric Specimens: T1 and T2* Measurements Using Ultrashort Echo Time (UTE) MR Imaging in 3T

Computer 56

Berna Dirim1,2, Jiang Du1, Sheronda Statum1, Richard Znamirowski1, Byung Pak1, Graeme Bydder1, Christine B. Chung1

1University of California San Diego, San Diego, California , USA; 2Izmir Ataturk Egitim ve Arastirma Hastanesi , Izmir, Turkey

Little or zero signal is detected from the short T2 tissues with routinely used pulse sequences. UTE pulse sequences can detect signals from these tissues; allow them to be imaged and quantified. We present UTE imaging (minimal TE = 8 &[micro]s)and quantitative T1 and T2* characterization of the connective tissues. Six frozen hand specimens were used. Dual echo UTE pulse sequence, for T1 measurement a UTE saturation recovery technique and T2* measurement UTE acquisition with variable TE delays were applied. UTE sequences provide high signal imaging of them and T1, T2* measurements to evaluate them using a clinical scanner.

 

14:30         3641.     Ultrashort TE (UTE) Imaging of the Extensor Tendon Functional Entheses of the Finger

Computer 56

Richard Znamirowski1, Mark Bydder1, Christine B. Chung1, Jiang Du1, Atsushi Takahashi2, Won Bae1, Sheronda Statum1, Graeme M. Bydder1

1University of California, San Diego, San Diego, California , USA; 2GE Healthcare Technologies, Menlo Park, California , USA

Entheses are regions where tendons, ligaments or joint capsules are connected to bone. Conventional clinical magnetic resonance (MR) imaging has not been helpful in demonstrating the key tissues present in normal entheses. All these tissues have short transverse relaxation times (T2s), and show little or no signal with typical clinical pulse sequences which have echo times (TEs) of about 8-20 msec or longer. As a result the component tissues of entheses have not previously been identifiable with imaging. Here we report ultrashort TE (UTE) imaging of finger enthesis with high spatial resolution and contrast using a purpose designed finger coil.

 

15:00         3642.     A Comparison of UTE Versus SPRITE for Robust MR Imaging of Short T8 Components

Computer 56

Alexandre A. Khrapitchev1, Nicola R. Sibson1, Matthew D. Robson1, Andrew M. Blamire,12

1University of Oxford, Oxford, UK; 2University of Newcastle, Newcastle, UK

This is a practical comparison between SPRITE and UTE on a 7T animal system. SPRITE is more suitable for imaging of extremely short T8 species, but requires some extra care to avoid damaging gradient systems. UTE can provide shorter examination times but is more challenging to implement and is sensitive to gradient imperfections.

 

Small Animal Musculoskeletal Imaging

Hall D                                   Tuesday 13:30-15:30                                                                                                                                             

13:30         3643.     Simultaneous Non-Invasive Determination of Tissue Perfusion, Arterial Blood Pressure and Peripheral Vascular Resistances in Mice

Computer 57

Jacques Ménard1, Eric Giacomini1, Céline Baligand1, Didier Bertoldi1, Pierre Carlier2

1Institute of Myology , Paris, France; 2Institute of Myology, Paris, France

We developed a new multiparametric 1H-NMR approach to explore non-invasively the muscular microcirculation in mice. Using a custom-developed setup, we have automated a procedure that allows dynamic determination of skeletal muscle perfusion, systemic blood pressure and vascular resistances in mice. Within a single NMR examination, this non-invasive NMR method can be used to explore the microcirculation control in mouse models. As an application, we showed in vivo that peripheral vascular resistances were increased in the skeletal muscle of db/db mice suffering from type-2 diabetes mellitus.

 

14:00         3644.     Simultaneous High-Resolution Imaging of Mouse Knee and Ankle at 3.0T Using a Specially Designed Dual Array Coil
[Not Available]

Computer 57

Zhigang You1, Wingchi Edmund Kwok1, Steve Proulx1, Edward Schwarz1

1University of Rochester, Rochester, New York, USA

We have been conducting longitudinal mice knee studies to evaluate arthritides.  To enable evaluation of extra-articular manifestations of arthritides and development of multi-organ models, we developed a dual RF coil for simultaneous imaging of mouse knee and ankle at 3T.  Since this coil covers only the joint regions needed to be imaged, the total effective coil volume is minimized resulting in high SNR to support high-resolution imaging with 100-micron level resolution.  Preliminary data on transgenic mice show this coil can provide information potentially useful for the development of multi-organ models.  It should be useful for longitudinal mouse studies of arthritides.

 

14:30         3645.     MR Texture Analysis of Regenerating Mouse Muscle at 7T: An In-Vivo Study

Computer 57

Sandra Même1, Catherine Sébrié2, Jean-Claude Beloeil1, Brigitte Gillet2

1CNRS CBM UPR4301, Orléans, France; 2ICSN CNRS UPR2301, Gif-sur-Yvette, France

The mdx mouse is a model of human muscular dystrophy characterized by a genetic deficiency for dystrophin which leads to numerous spontaneous muscle fibers degeneration-regeneration cycles which are difficult to interpret. A mouse model of muscle injury (with injection of notexin) involving a single well-defined cycle of degeneration-regeneration was studied to distinguish between these two processes, using  both MRI texture analysis and histological data. More precisely the aim of this study was to a) monitor the muscle degeneration-regeneration process and b) to define more precisely the local variations of the muscle texture after notexin injection .

 

15:00         3646.     In Vivo MRI of Rabbit Intervertebral Disc Degeneration at 9.4 T: MR Parameters Quantification Allows Identification of Degenerative Discs

Computer 57

Fanny Noury1, Sandra Même1, Jean-Claude Beloeil1, Bich-Thuy Doan1,2

1CBM - CNRS UPR4301, Orleans, France; 2ICSN - CNRS UPR2301, GIF-SUR-YVETTE, France

Intervertebral disc (IVD) degeneration is a complex process characterized by biochemical and structural changes. To study these mechanisms, we follow up the in vivo IVD degeneration by MRI on a rabbit animal model of human lumbar diseases at 9.4 T. To our knowledge, this is the first in vivo study of rabbit IVD degeneration at high magnetic field.

We were able to establish a disc degeneration phase classification to characterize the disc degeneration processes chronology.

This work is a part of a larger project, aiming to estimate the efficiency of new disc restitution methods in rabbit.

 

Cartilage

Hall D                                   Wednesday 13:30-15:30                                                                                                                                       

13:30         3647.     Enhancement of MT, CEST and NOE Contrast Via Intermolecular Multiple Quantum Coherences

Computer 56

Wen Ling1, Uzi Eliav1, Xu Yang2, Gil Navon1, Alexej Jerschow2

1Tel Aviv University, Israel; 2New York University, New York, New York, USA

We demonstrate that using intermolecular multiple-quantum coherences can enhance contrast in MTC/CEST/NOE experiments in proportion to (Mz/Mo)p, where Mz  is the the saturated level of the z-component of the magnetization, Mo its value in equilibrium and l is the coherence order used. These methods are demonstrated on a series of glycosaminoglycan (GAG) samples, and also for a piece of bovine articular cartilage.

 

14:00         3648.     in-vivo T8 Mapping and DGEMRIC of Human Hip Cartilage at 1.5T

Computer 56

Matthew F. Koff1, David W. Stanley2, Michele R. D'Apuzzo1, Robert T. Trousdale1, Kimberly K. Amrami1, Kenton R. Kaufman1

1Mayo Clinic, Rochester, Minnesota, USA; 2GE Healthcare, Proctor, Minnesota, USA

This study evaluated in-vivo T1 and T2 values of hip cartilage. Coronal T2-weighted images centered on the femoral head were acquired. After administration of Gd-DPTA2- followed by walking and rest, coronal T1-weighted images were acquired. Bulk and depth dependent T1 and T2 values of acetabular and femoral cartilages were calculated. No differences between the bulk T1 or T2 values were found. Femoral cartilage T1 values increased significantly from the superficial zone to the deep zone. The current T1 and T2 values are similar to subjects with known pathologies. The combined scanning method enables a comprehensive quantitative analysis of hip cartilage.

 

14:30         3649.     SPGR and GRE Cartilage Imaging of the Knee at 3T with Water Excitation and 2D Autocalibrating Parallel Imaging

Computer 56

Richard Kijowski1, Reed Busse2, Scott Reeder1, Kuya Takami1, Philip Beatty3, Anja Brau3, Anthony Vu4

1University of Wisconsin, Madison, USA; 2General Electric Healthcare, Madison, USA; 3General Electric Healthcare, Menlo Park, USA; 4General Electric Healthcare, Waukesha, USA

The purpose of this study was to document the feasibility of performing dark fluid SPGR and bright fluid GRE cartilage imaging at 3T using water excitation (SSI) and an autocalibrating 2D-accelerated parallel imaging technique called ARC.  SSI-SPGR and SSI-GRE sequences with and without ARC parallel imaging were performed twice on the knees of 8 asymptomatic volunteers.  SNR efficiency and CNR efficiency measurements were performed using a double acquisition addition/subtraction method. ARC accelerated SPGR and GRE cartilage imaging without causing a reduction in SNR and CNR efficiency.

 

15:00         3650.     High-Resolution Morphological and Biochemical Imaging of Articular Cartilage of the Ankle Joint at 3.0 T Using a New Dedicated Phased Array Coil: In-Vivo Reproducibility Study

Computer 56

Goetz Hannes Welsch1, Tallal Charles Mamisch2, Michael Weber1, Stefan Nemec1, Klaus Bohndorf3, Siegfried Trattnig1

1Medical University of Vienna, Vienna, Austria; 2University of Berne, Berne, Switzerland; 3Klinikum Augsburg, Augsburg, Germany

MRI of thin cartilage layers puts challenging demands on imaging techniques. High resolution with sufficiently SNR has to be achieved without prolonging acquisition time too much. High-field-MRI, advanced coil technology, sophisticated sequences and imaging techniques provide the basis of the imaging protocol used in this study.The object was to determine the precision of high-resolution isotropic 3D-TrueFISP imaging of ankle cartilage and to show the feasibility of quantitative T2-imaging.To best of our knowledge this is the first study to evaluate in-vivo high-resolution morphological isotropic(0.31x0.31x0.31mm3) TrueFISP-imaging and biochemical T2-mapping within the ankle joint in a clinically acceptable scan-time of each about 10 minutes.

 

13:30         3651.     Quantitative and Qualitative Assessment of Multiple New 3T Cartilage Imaging MR Pulse Sequences

Computer 57

Richard Kijowski1, Jessica Klaers1, Kuya Takami1, Kirkland Davis1, Michael Tuite1, Kazuhiko Shinki1, Anthony Vu2, Scott Reeder1, Walter Block1, Reed Busse3

1University of Wisconsin, Madison, USA; 2General Electric Healthcare, Waukesha, USA; 3General Electric Healthcare, Madison, USA

This study was performed to compare multiple promising new MR pulse sequences for evaluating the articular cartilage of the knee joint at 3T. FSE-Cube, MENSA, IDEAL-GRASS, IDEAL-SPGR, COSMIC, and VIPR-SSFP sequences were performed on the knees of 10 asymptomatic volunteers and 5 patients with osteoarthritis.  SNR and CNR measurements were obtained. A qualitative assessment of image quality was performed by 3 musculoskeletal radiologists.   All sequences had certain strengths and weaknesses with no clear cut “winner” in the quantitative and qualitative comparison.  The relative advantages and disadvantages of each sequence may make them best suited for different cartilage imaging applications.

 

14:00         3652.     Correlation of DTI Derived Metrics with Synovial Fluid Inflammatory Cytokines from Patients of Arthritis with Inflammation of the Knee Joint

Computer 57

Manoj Kumar1, Vikas Agarwal1, Ram KS Rathore2, Amit Prasad1, Jitesh Kumar Singh2, Ram Nath Mishra1, Kashi N. Prasad1, Rakesh K. Gupta1

1Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India; 2Indian Institute of Technology, Kanpur, India

The inflammation that accompanies the pain and swelling associated with inflammatory arthritis is mediated by complex interactions of inflammatory cytokines. DTI was performed in 7 arthritis patients with inflammation (three osteo and four rheumatoid arthritis). JAVA based software was used for DTI data process as well as cartilage segmentation. Synovial fluid was taken from knee joints of these patients and inflammatory cytokines were quantified by ELISA technique. The Pearson’s correlation between DTI derived metrics and inflammatory cytokines was significant. DTI derived metrics and inflammatory cytokines may be used as surrogate markers for the activity of disease in arthritis patients.

  

14:30         3653.     Quantification of Capillary Blood Flow and Endothelial Permeability in Inflammatory Joint Diseases: MR-Perfusion Results

Computer 57

Sabine Weckbach1, Steven P. Sourbron1, Mike Notohamiprodjo1, Hans Hatz2, José Raya1, Maximilian F. Reiser1, Christian Glaser1

1University Hospital Munich- Grosshadern, Munich, Germany; 2Klinik Feldafing, Feldafing, Germany

By using a two-compartment model and an MR sequence with high temporal resolution a separate quantification of blood flow and permeability in patients with inflammatory joint diseases seems possible with stable and plausible results. Compared to previous studies a direct measurement of capillary blood flow and a ROI-based mapping of perfusion parameters might improve sensitivity and specificity with regard to future therapy control studies.

  

15:00         3654.     Assessment of T1 and T2 MRI Parameters as a Predictors of Cartilage Implants Maturation: The Equine Subject Study

Computer 57

Vladimir Juras1,2, Pavol Szomolanyi,23, Zuzana Majdisova,23, Siegfried Trattnig3

1Medical University of Vienna, Vienna, Austria; 2Slovak Academy of Sciences, Bratislava, Slovakia; 3MR Centre / Highfield MR, Medical University of Vienna, Vienna, Austria

Qualitative and quantitative assessments of MR relaxation parameters T1 and T2 in equine articular cartilage were compared to histology grading. Equine subjects were treated by Matrix-associated Autologous Chondrocyte Implantation (MACI) with three different implant routinely used in clinical applications. The degree of the maturation process could be determined by zonal T2 organization and by absolute quantification of relative R1 of native and repaired cartilage. T2 reflects the matrix organization, whilst R1 is related to proteoglycans content. The results proved that MRI can be prospectively used as a non-invasive imaging modality for post operative monitoring following autologous chondrocyte implantation.

 

13:30         3655.     T1ρ Relaxation Evaluation of Knee OA in  a Guinea Pig Model

Computer 58

Chenyang Wang1,2, Matt Fenty1, Ari Borthakur1, George Dodge2, Ravinder Reddy1

1University of Pennsylvania, Philadelphia, Pennsylvania, USA; 2Thomas Jefferson University, Philadelphia, Pennsylvania, USA

Osteoarthritis (OA) is a painful and costly medical condition, affecting millions of people every year. In this study, we intend to demonstrate the feasibility of using T1ρ MRI to monitor the progression of OA in a spontaneous animal model. The animal model is based on Dunkin-Hartley guinea pigs, which have been shown to spontaneously develop OA as they age.  In addition, T1ρ MRI has been shown to be sensitive to OA changes in human and bovine cartilage.  Since T1ρ MRI is non-invasive, this animal model of OA can be used to evaluate the efficacy of potential OA therapies in vivo.

 

14:00         3656.     7 Tesla MR - Initial Results on T2 and T2* Mapping of Healthy Articular Cartilage and Cartilage Repair Tissue

Computer 58

Goetz Hannes Welsch1, Tallal Charles Mamisch2, Sebastian Quirbach1, Timothy Hughes3, Oliver Kraff4, Mark E. Ladd4, Christoph Zilkens5, Oliver Bieri6, Klaus Scheffler6, Siegfried Trattnig1

1Medical University of Vienna, Vienna, Austria; 2University of Berne, Berne, Switzerland; 3Siemens Medical Solutions, Erlangen, Germany; 4University of Essen, Essen, Germany; 5University od Duesseldor

Ultra-high-field whole body systems (7.0T) have high potential in future human in-vivo MRI. In musculoskeletal MRI mainly biochemical imaging of articular cartilage may benefit. Here T2 mapping has shown its potential, also in the evaluation of zonal variation as an indicator of hyaline or hyaline-like articular cartilage, however implying high spatial resolution. Thus the aim of our study was to show the feasibility of T2 and additionally T2* relaxation measurements at 7T MRI as well as to evaluate its potential in an initial patient study after matrix associated autologous chondrocyte transplantation (MACT) within the knee.

 

14:30         3657.     Reproducibility of Automatic Quantitative Analysis of the Articular Cartilages from MEDIC and WeDESS Magnetic Resonance Images of the Knee at 1.5T [Not Available]

Computer 58

Jurgen Fripp1,2, Valer Jurcak2, Ross Holt3, Sebastien Ourselin1, Craig Engstrem2, Stuart Crozier2

1BiomedIA Lab, e-Health Research Center, Brisbane, Australia; 2University of Queensland, Brisbane, Australia; 3Southernex Imaging, Australia

We present a cartilage segmentation approach for MRIs of the knee and test the reproducibility and test-retest error found when acquiring weDESS and MEDIC images from healthy volunteers at 1.5T.

 

15:00         3658.     dGEMRIC at 7 Tesla - Feasibility Study

Computer 58

Siegfried Trattnig1, Goetz H. Welsch1, Katja Pinker1, Timothy Hughes2, Oliver Kraff3, Mark Ladd3, Pavol Szomolanyi1,4, Oliver Bieri5, Klaus Scheffler5, Tallal C. Mamisch6

1MR Centre - Highfield MR, Vienna, Austria; 2Siemens AG, Erlangen, Germany; 3University Hospital, Essen, Germany; 4Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia; 5

For the quantification of glycosaminoglycan content in articular cartilage delayed Gadolinium Enhanced Magnetic Resonance Imaging of Cartilage (dGEMRIC) is the method of choice.

Ultrahigh field (7T) systems are increasingly used for clinical studies in patients, which provide higher resolution and which may improve diagnostic accuracy.

In this  study the feasibility of dGEMRIC technique at 7T was shown in phantoms and in volunteers with a range between pre-and postcontrast T1 values at 7T similar to 3T. However, to get reliable results inversion recovery technique for T1 mapping has to be performed and the calculation of the delta relaxation rate is mandatory.

 

13:30         3659.     Novel Usages of Distance Function in Fully Automatic Articular Cartilage Segmentation

Computer 59

Feng Huang1, Xiaoming Chen2, Deliang Ye1, Sarah Hertel3

1Invivo Corporation, Gainesville, Florida, USA; 2University of Florida, Gainesville, Florida, USA; 3Invivo Corporation, Pewaukee, Wisconsin, USA

In this study, we propose to use distance function to attack several difficulties in cartilage segmentation. Distance function of an object is defined as the smallest distance from a point in the domain to the object. Given segmented bones, distance function of these bones can be calculated. In this work, distance function is proposed to:  1) reduce the search region of cartilages; 2) segment cartilages based on the smoothness of cartilage thickness when there is no contrast between cartilages and surrounding soft tissues; 3) separate contacted cartilages when there is no obvious contrast between them; 4) provide thickness map for cartilages. The proposed method was tested on twelve MRI data sets.

 

14:00         3660.     Development of T-Scores for the Diagnosis of Osteoarthrosis of the Patellofemoral Joint Using Quantitative MR Volumetry of Cartilage

Computer 59

Sabine Weckbach1, Annie Horng1, Gudrun Pforte1, Raya José1, Felix Eckstein2, Martin Hudelmeier3, Maximilian F. Reiser1, Christian Glaser1

1University Hospital Munich- Grosshadern, Munich, Germany; 2Paracelcus Medical University, Salzburg, Austria; 3Insitute of Anatomy, Salzburg, Austria

The purpose of this study was to evaluate T-scores based on quantitative cartilage volumetric parameters for the diagnosis of patellofemoral osteoarthritis. Sensitivities and specificities obtained for selected cutoff values suggest that T-scores based on quantitative cartilage volumetric parameters may be a suitable adjunct for the diagnostic workup of OA in population based studies / approaches.

 

14:30         3661.     Kinematic Biochemical Studies of Cartilage Transplants at 3Tesla

Computer 59

Siegfried Trattnig1, Tallal Ch. Mamisch2, Christina Plank1, Pavol Szomolanyi1,3, Sebastian Quirbach1, Goetz H. Welsch1

1MR Centre - Highfield MR, Vienna, Austria; 2Inselspital, Bern, Switzerland; 3Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia

A flexible knee coil which allows to assess quantitative cartilage MR data in different positions from 40° flexion to full extension was applied to examine in T2 and diffusivity values in the femoral cartilage of volunteers and patients after autologous chondrocyte transplantation (ACI). Changes of T2 and diffusivity in cartilage could be demonstrated by position dependent contact of two cartilage layers alone. Since repair tissue shows a different behaviour in the contact zone compared to healthy cartilage a possible marker for an improved evaluation of the repair tissue quality after ACI may be available providing biomechanical information on cartilage transplant.

 

15:00         3662.     3D GRE Sequence with Two Different Flip Angle Excitation Pulses for Zonal T1- Mapping of Articular Cartilage at 3T:  One-Year Follow-Up in Patients After Matrix-Associated Autologous Chondrocyte Transplantation (MACT) of the Knee Joint

Computer 59

Katja Pinker1, Pavol Szomolanyi2, Goetz Welsch1, Tallal Charles Mamisch3, Stefan Marlovits4, Siegfried Trattnig1

1MR Centre of Excelllence, Vienna, Austria; 2Slovak Academy of Sciences, Bratislava, Slovakia; 3Inselspital, Bern, Switzerland; 4Medical University Vienna, Vienna, Austria

To evaluate the global and zonal distribution of glycosaminoglycans (GAG) in normal weight-bearing cartilage and repair tissue by dGEMRIC method using a 3D GRE sequence with a 35/10° flip angle excitation pulse combination and to monitor the development of zonal and global GAG content in MACT over one year.

 

Musculoskeletal Miscellaneous

Hall D                                   Thursday 13:30-15:30                                                                                                                                           

13:30         3663.     Magnetization Transfer Effects in Human Median Nerve at 3 T [Not Available]

Computer 57

Giulio Gambarota1, Ralf Mekle1, Rolf Gruetter1,2

1Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland; 2University of Lausanne and University of Geneva , Switzerland

The values of magnetization transfer (MT) ratio are well established for most clinical relevant tissues. However, despite the potential of MT contrast to assess demyelination, which is one of the common features of a number of peripheral nervous system (PNS) pathologies, no measurements of MTR have been performed to date on human PNS. The purpose of this study was to determine the MTR in human median nerve to provide baseline values of MTR for the PNS in healthy volunteers.

 

14:00         3664.     High-Resolution MR Imaging of the Foot: Magnetization Transfer Effects in Foot Peripheral Nerves

Computer 57

Giulio Gambarota1, Ralf Mekle, Rolf Gruetter1,2

1Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland; 2University of Lausanne and University of Geneva, Switzerland

MT contrast in foot nerves could be of interest for early detection of diabetes-induced peripheral neuropathy. In this work, we sought to image foot nerves and to measure the MT ratio (MTR), at 3 T. A substantial reduction of MTR was observed in the nerves (MTR in 25-35% range), compared to muscle (42-50% range). The results of this study indicate that the high signal-to-noise ratio afforded at the field strength of 3 T and the use of high-sensitivity coils allows not only for the visualization of foot nerves but also for quantitative assessment of their intrinsic MR properties.

 

14:30         3665.     Consistent Automated Scan Planning of Shoulder

Computer 57

Chiel JM den Harder1, Johan W. de Jong1, Clemens Bos1, Marius van Meel1, Daniel Bystrov2, Harald Heese2, Arjan W. Simonetti1

1Philips Medical Systems, Best, Netherlands; 2Philips Research Laboratories, Hamburg, Germany

Consistent planning of MRI scans of patients who undergo a shoulder examination is very important. It enables radiologists to investigate the patients’ anatomy with a preferred ‘orientation’. However, planning between operators may be biased due to their training, competence and experience. To deal with this problem, an automated scan planning for shoulder examinations was developed and a feasibility study was performed. The study showed that the proposition of the system was in line with manual planning of an experienced operator. The automated scan planning procedure can be integrated into the examination protocol, thus improving workflow and achieving a one push button examination.

 

15:00         3666.     MRI of an Egyptian Mummy on Clinical 1.5 and 3 T Whole Body Imagers

Computer 57

Michael Bock1, Peter Speier2, Sonia Nielles-Vallespin2, Michael Szimtenings2, Karin Leotta1, Frank Rühli3

1Deutsches Krebsforschungszentrum (dkfz), Heidelberg, Germany; 2Siemens Medical Solutions, Erlangen, Germany; 3University of Zurich, Zürich, Switzerland

Non-destructive proton MRI of the head of an Egyptian mummy was performed on 1.5 T and 3 T clinical MRI systems. Three different pulse sequences were used that offered echo times below 1 ms to overcome the low SNR due to the short T2* of the mummified tissue. Of these, a 3D radial pulse sequence offered the highest SNR per unit time, and 3D data sets of excellent quality could be acquired in less than 1 hour.

 

13:30         3667.     Responsiveness of BOLD MRI to Short-Term Temperature Changes of the Rabbit Knee Joint in Inflammatory Arthritis

Computer 58

Cristina Otilia Nasui1, George Nathanael, Elka Miller, Jaques Belik, Adrian Crawley, Andrea S. Doria

1Hospital for Sick Children, Toronto, Canada

BOLD MRI is a suitable tool to assess local tissue oxygen levels as dependent on local temperature with most significant responsiveness changes noted in the knee contralateral to the knee where arthritis was induced. Physiologic compensatory mechanisms in the contralateral joint may explain these results.  Further assessment of responsiveness of BOLD MRI in arthritic joints with higher magnetic field scanners may confirm the current results and enhance potential changes.

 

14:00         3668.     Isotropic MRI of the Ankle at 3.0T Using 3D-FSE-Cube with Extended Echo Train Acquisition (XETA)

Computer 58

Garry E. Gold1, Reed F. Busse2, Kathryn J. Stevens1, Eric Han3, Anja C.S. Brau3, Philip J. Beatty3, Christopher F. Beaulieu1

1Stanford University, Stanford, California , USA; 2GE Healthcare, Madison, Wisconsin, USA; 3GE Healthcare, Menlo Park, California , USA

Two-dimensional fast spin-echo (2D-FSE) is frequently used to evaluate the ankle joint.  This approach is limited, however, by partial volume artifacts and slice gaps.  Volumetric acquisition with isotropic resolution overcomes these limitations and allows reformations in multiple planes.  We compared 2D-FSE in the ankle at 3.0T with 3D-FSE-Cube, a new technique with a variable refocusing flip angle eXtended Echo Train Acquisition (XETA) and 2D-accelerated autocalibrated parallel imaging (ARC) to achieve isotropic resolution in clinical feasible scan times.  3D-FSE-Cube showed high signal-to-noise and had the ability to reformat in any plane, making multiple 2D acquisitions unecessary.   3D-FSE-Cube is a promising method for clinical ankle imaging.

 

14:30         3669.     Spectroscopic Imaging Using Interleaved Projection Sampling Along the 3D Cartesion Phase and Slice Encodings (SIPPS): Application to Articular Cartilage

Computer 58

Jiang Du1, Christine B. Chung1, Graeme M. Bydder1

1University of California, San Diego, San Diego, California , USA

Fat water separation is of important clinical applications. Conventional fat saturation pulse is efficient but may provide non-uniform fat suppression and reduced water signal in regions of field inhomogeneity. Two-point or multi-point Dixon techniques are extensively investigated for robust fat water separation. Here we present a time efficient and robust fat water separation technique based on spectroscopic imaging using interleaved projection sampling along the 3D Cartesian phase and slice encodings (SIPPS), which provides high resolution 3D water and fat images at a series of resonance frequencies.

 

15:00         3670.     Orientational Effect on Achilles Tendon Investigated with Ultrashort TE Spectroscopic Imaging (UTESI) Sequence

Computer 58

Jiang Du1, Byung C. Pak1, Atsushi Takahashi2, Richard Znamirowski1, Sheronda Statum1, Graeme M. Bydder1, Christine B. Chung1

1University of California, San Diego, San Diego, California , USA; 2GE Healthcare Technologies, Menlo Park, California , USA

Fat water separation is of important clinical applications. Conventional fat saturation pulse is efficient but may provide non-uniform fat suppression and reduced water signal in regions of field inhomogeneity. Two-point or multi-point Dixon techniques are extensively investigated for robust fat water separation. Here we present a time efficient and robust fat water separation technique based on spectroscopic imaging using interleaved projection sampling along the 3D Cartesian phase and slice encodings (SIPPS), which provides high resolution 3D water and fat images at a series of resonance frequencies.

 

Muscle

Hall D                                   Thursday 13:30-15:30                                                                                                                                           

13:30         3671.     Mapping of Movements in the Dynamically Contacting Human Triceps Surae Muscles Using a Computer Controlled Hydraulic Foot-Pedal Device with Velocity Encoded Phase Contrast MRI

Computer 59

Dongsuk Shin1, Ryuta Kinugasa2, Chandan Mishra2, John Hodgson1, V. Reggie Edgerton1, Shantanu Sinha2

1University of California, Los Angeles, California , USA; 2University of California, San Diego, California , USA

The new hydraulic foot-pedal device was developed to create the dynamic and active muscle contractions inside the MRI bore. In comparison to the isometric contraction mode, the velocity/displacement behavior was changed, providing new insights in muscle-tendon mechanics previously undetectable under the isometric contraction mode.

 

14:00         3672.     Three-Dimensional Muscle Models of the Human Triceps Surae Muscle-Tendon Complex

Computer 59

Dongsuk Shin1, Sheng-Wei Chi1, Jiun-Shyan Chen1, John Hodgson1, V. Reggie Edgerton1, Shantanu Sinha2

1University of California, Los Angeles, California , USA; 2University of California, San Diego, California , USA

We propose a newly developed three-dimensional FE model that incorporates the aponeurosis-tendon unit as well as soleus muscle. The outcome of the model demonstrates the inhomogeneous strain distribution along the aponeurosis-tendon complex under different MVC levels, which is in good agreement with our previously reported PC-MRI data. The model suggests geometrical changes in the muscle-tendon system, recruitment of active/passive components, and ankle rotation all may contribute to non-uniform strain distribution.

 

14:30         3673.     Muscle Functional Magnetic Resonance Imaging Using Ultrafast Imaging

Computer 59

Noriyuki Tawara1, Osamu Nitta2, Hironobu Kuruma2, Mamoru Niitsu2, Akiyoshi Itoh3

1Japan Institute of Sports Sciences, Kita-ku, Japan; 2Tokyo Metropolitan University, Arakawa-ku, Japan; 3NIHON University, Funabashi-sity, Japan

Exercise selectively increases the signal intensities (SI) of active muscles in T2-weighted magnetic resonance (MR) images. Investigators in sports medicine and other related fields have utilized T2 maps to investigate skeletal muscle activity during exercise. However, scan time of T2-weighted MR images is usually for a few minutes. So, we can choose only the location that is secured for long time. In this paper, we report the speed-up of fusion image of magnetic resonance imaging for visualization of muscle activity. Spin-echo echo-planar-imaging (SE-EPI) that is ultrafast imaging has weak-point that is low spatial resolution. In order to compensate for weak-point, we used TrueFISP that is ultrafast imaging of high spatial resolution. And we proposed the new method using fusion SE-EPI and TrueFISP. We compared skeletal musclefs T2 relaxation curve between SE-PEI and multiple spin echo (MSE) that is conventional method, SE-EPI is similar to MSE in short TE. In short TE than 75 ms, SE-EPI indicated the possibility of use in pulse sequence of T2-weighted MR images. Also, a 1/13 was able to shorten it than MSE sequence in MRIfs scanning time.

 

15:00         3674.     Quantitative Assessment of Muscle Degeneration in DM1 Patients Using MRI [Not Available]

Computer 59

bassem Hiba1, Nathalie Richard1, Luc J. Hébert2, Christophe Vial3, Mimoun Nejjari1, Jean francois Remec3, Chantale coté2, Francoise Bouhour3, Jack Puymirat*2, Marc Janier1,4

1Université Lyon1, Lyon, France; 2Laval CHU, Québec, Canada; 3Wertheimer Hospital, Lyon, France; 4Hospices Civils de Lyon, Lyon, France

MRI is a very promising technique for muscle degeneration exploration, even though only some descriptive or qualitative results were reported in the literature. We propose a quantitative exploration of muscle degeneration in Steiner’s myotonic dystrophy using MRI (particularly in Tibialis Anterior muscles). 17 DM1 patients and 6 controls were included in the study, normal and degenerated tissue volumes, oedema volume and the fat to water ratio were assed from MR images. The proposed measurements were validated comparing with relative isometric strength measured by a hand-held dynamometer.

 

13:30         3675.     Evaluation of Muscle Fiver Tractography by Single-Shot Diffusion Tensor STE EPI

Computer 60

Jyunichi Hata1, Kazuo Yagi1, Keigo Hikishima1, Ryou Takaki1, Yuuji Komaki1

1Tokyo Metropolitan University, Arakawa, Japan

The STE method can achieve high SNR in the diffusion weighted image of the skeletal muscle. We mounted DT STE-EPI on 1.5T MRI scanner and evaluated Toractography of the human skeletal muscle. Result, It is necessary to impress about at least b-value 800-1000 [s/mm2] to the muscle fiber tracking as well as central nerve area. The muscle fiber toractography showed the anatomical structure similar to fiber structure measured by other modalities. Muscle fiber Toractography will do a contribution to the muscle disease diagnosis, the muscle function evaluation, and the sport medicine in the future.

 

14:00         3676.     Continuous Arterial Spin Labeling in Progressive Peripheral Vascular Disease

Computer 60

Wen-Chau Wu1, Jiongjiong Wang1, Ping Wang1, John A. Detre, Temitope Olufade, Thomas F. Floyd1

1University of Pennsylvania, Philadelphia, USA

Measurement of muscle perfusion in the extremities is feasible using arterial spin labeling (ASL) MRI. In this study, we utilize continuous ASL (CASL) to measure the perfusion in patients with peripheral vascular disease. Flow variability is analyzed for individual muscle groups and correlated to the disease severity assessed by the ankle to brachial index (ABI). Results show that CASL flow measurements correlate with disease state as measured by ABI, but also demonstrate a retained microvascular flow reserve in the presence of early to intermediate vascular disease. Progression of disease is followed by diminished flow reserve and delayed hyperemic response.

 

14:30         3677.     Magnetisation Transfer Ratio in Leg Muscle, and Sciatic Nerve Size in Hereditary Demyelinating and Chronic Inflammatory Demyelinating Polyneuropathy

Computer 60

Peter Oliver Cowley1, Mario Miranda1, John Thornton2, Lisa Strycharczuk11, Hiten Mehta1, Mary Reilly1, Martin Koltzenburg1, Tarek Yousry1

1National Hospital for Neurology and Neurosurgery, London, UK; 2National Hospital for neurology and neurosurgery, London, UK

Sciatic nerve cross-sectional area in the thigh and calf-muscle magnetisation transfer ratios (MTRs) were determined in patient groups with inherited (CMT1a) and acquired (CIDP) peripheral neuropathies and a control group (n=10 in each group).  Sciatic nerve areas were significantly enlarged in both disease groups, to a greater degree in CMT1a (p<0.001).  MTRs were reduced in affected muscle groups, the reduction correlating with age (and presumed disease duration) in the CMT group.

 

15:00         3678.     Relaxation Times of Human Skeletal Muscle Metabolites at 7T [Not Available]

Computer 60

Ligong Wang1, Nouha Salibi2, Mark E. Schweitzer1, Ravinder R. Regatte1

1Center for Biomedical Imaging, NYU School of Medicine, New York, USA; 2Siemens Medical Solutions, Malvern, Pennsylvania, USA

This study reports ultra high field (7T) proton relaxation times of lipid metabolites in human tibialis anterior muscles. T1 and T2 relaxation times of lipid phantom (corn oil) and healthy human volunteers (n=3) were measured using single voxel 1H MR spectroscopy of skeletal muscle. The T1 values of TMA, Cr-CH3, IMCL-CH2, and EMCL-CH2 for TA muscle at 7T are 1310, 1516, 1605, and 1479 ms, while the T2 values of the corresponding metabolites are 62.4, 56.81, 57.9, and 58.5 ms. The relaxation numbers can be utilized for the absolute quantification of skeletal muscle metabolite concentrations and optimization of sequence parameters.

 

Renal Parenchyma & Perfusion

Hall D                                   Monday 14:00-16:00                                                                                                                                             

14:00         3679.     Renal Cortical and Medullar Oxygenation Changes After Oxygen Challenge: Evaluation with BOLD MRI

Computer 61

Hersh Chandarana1, Mohit Naik1, Pippa Storey1, Vivian Lee1, Bachir Taouli1

1NYU Medical Center, New York, New York, USA

In this study we evaluated the effect of inhaled oxygen on changes in renal cortical and medullary T2* signal with BOLD imaging in patients with normal renal function. Our study demonstrates significant increase in oxygenation of the medulla (mean 12.2%) and to a lesser extent in the cortex (2.4%), confirming that in normal kidneys, the medulla is more hypoxic than the cortex and demonstrates significant change in oxygenation after oxygen challenge.

 

14:30         3680.     Clinical Value of MR-Based Quantification of Renal Perfusion Parameters with a Separable Two-Compartment Model

Computer 61

Ulrike Attenberger1, Henrik Michaely2, Steven Sourbron3, Mike Notohamiprodjio3, Christian Glaser3, Maximilian Reiser3, Stefan Schoenberg2

1Ludwig-Maximilians University Munich, Munich, Germany; 2University of Heidelberg, Germany; 3Ludwig-Maximilians University Munich, Germany

The combination of MR angiography and MR perfusion (MRP) measurements offers a promising method for detection of macrovascular and microvascular renal disease in a single exam. So far, there is no ideal technique for direct measurement of renal function.

We used a separable two-compartment model for quantification of renal perfusion paramters in this study and investigated the diagnostic accuracy of a combined MRA/MRP approach compared to the final clinical diagnosis. 25 patients underwent renal perfusion measurements and renal MR angiograpyh at a 3.0T scanner (Siemens Magnetom Tim Trio). The sequence parameters of the SR-TurboFLASH sequence were: TR / TE/ TI [ms] 203/0.90/101, flip angle 12º, bandwith [Hz/Px] 900, matrix  192x134, FOV[mm3] 450x373, temporal resolution [slice/s] 5, parallel imaging GRAPPA 2. The sequence parameters of the 3D MRA sequence were: TR/ TE [ms] 3.11/ 1.09, flip angle 23º, bandwidth [Hz/Px] 510, matrix 512x85%, FOV [mm²] 400x81.3%, phase oversampling [%] 8, interpolated slice thickness 0.9 [mm], voxel size [mm3] 0.65, spatial resolution [mm³] 0.9x0.8x0.9, scan time [s] 19.

From all patients the final clinical diagnosis was obtained as a reference standard. 15 patients were classified as ill based on the final clinical diagnosis. 3 patients with renal artery stenoses, 5 patients with renal insufficience in compensated retention, 7 patients after renal transplantation with postoperative complications

MRA alone had a sensitivity of 73% and specifity of 90%.  MRP reached a sensitivity of 100% and a specifity of 70% respectively. In combination MRA and MRP revealed a sensitivity of 100% and specifity of 90%.

We could show that the combination of both methods - MRA and MR perfusion - heightens overal diagnostic accuracy. Especially in patients with renoparenchymal diseases the additional information of perfusion measurements increases the diagnostic specifity.

 

15:00         3681.     Dual Navigator Gated FAIR True-FISP Pulse Sequence for Renal Perfusion Imaging

Computer 61

Ruitian Song1, Ralf Berthold Loeffler1, Claudia Maria Hillenbrand1

1St. Jude Children's Research Hospital, Memphis, Tennessee, USA

A dual navigator gated FAIR True FISP pulse sequence has been developed and implemented. Two navigators are applied to gate tagging and imaging slices, respectively. Since both slices are gated and followed to the same reference position, the imaging slice is prevented from moving to the edge of or out of the inversion slice. Error caused by not or not fully tagged spins could be eliminated in measuring renal perfusion rate, and pixel-mismatch between the tagging and control images could also be improved.

 

15:30         3682.     MR-Based Semi-Automated Quantification of Renal Perfusion Functional Parameters with a Two-Compartment Model - An Interobserver Analysis

Computer 61

Ulrike Attenberger1, Steven Sourbron1, Mike Notohamiprodjio1, Christian Glaser1, Maximilian Reiser1, Stefan Schoenberg2, Henrik Michaely2

1Ludwig-Maximilians University Munich, Munich, Germany; 2University of Heidelberg, Mannheim, Germany

Dynamic contrast-enhanced magnetic resonance imaging of the kidneys offers promising approaches for the assessment and differentiation of renovascular and renoparenchymal diseases. For the determination of both renal first-pass perfusion (plasma flow, plasma mean transit time) and renal filtration (tubular flow, tubular mean transit time) parameters we used a separable two-compartment model. The purpose of this study was to evaluate interobserver agreement in the quantitative assessment of renal functional parameters as it is known, that variability of functional parameters is a well-addressed problem. 12 consecutive patients (4 men, 8 women, mean age 51 years) underwent renal perfusion measurements after intravenous injection of 7 ml Gd-BOPTA (Multihance®, Bracco) at 4 ml/s at 3.0T (Magnetom Tim Trio). The sequence parameters of the SR-TurboFLASH sequence were: TR / TE/ TI [ms] 203/0.90/101, flip angle 12º, bandwidth [Hz/Px] 900, matrix  192x134, FOV[mm3] 450x373, temporal resolution [slice/s] 5, parallel imaging GRAPPA 2.Two independent observers placed regions of interest (ROIs) manually on an axial slice, one in the abdominal aorta for determination of arterial input function, one at the air-tissue interface for retrospective respiratory motion correction. Fitting the data on a pixel-by-pixel basis to the two-compartment model maps of the perfusion parameters and tubular filtration parameters were obtained. Pixels with plasma volume > 10 ml/100ml were selected to segmente a cortical ROI. The model fit was repeated on a ROI basis to produce the cortical averages. Correlations of all values were significant (p<0.05). A paired t-test yielded significant differences for plasma flow values (p=0.004). The data shows a systematic difference for the plasma flow parameter, while plasma mean transit time parameter seems to be most stabile.The difference in flow parameters reflects a user-dependent bias in AIF selection, which may be minimized in future work by incorporating (semi)automated segmentation to identify the lumen of the aorta.

 

14:00         3683.     QUIPSS II with Interleaved Thin-Slice TI1 Periodic Saturation for FAIR Sequence

Computer 62

Ruitian Song1, Ralf Berthold Loeffler1, Claudia Maria Hillenbrand1

1St. Jude Children's Research Hospital, Memphis, Tennessee, USA

QUIPSS II with interleaved thin-slice TI1 periodic saturation has been developed and integrated into a FAIR TrueFISP ASL experiment for the quantification of renal perfusion.  A periodic thin-slice saturation pulses were applied alternatively on both sides of the imaging slice from TI1 to TI1s (TI1 stop time). It has been shown that the bolus width can be controlled by changing TI1 and the better matched saturation slice profiles can be achieved.  The renal perfusion rate could be quantified more accurately with our technique

 

14:30         3684.     Evaluation of Dysfunctional Renal Transplants Using Low-Dose MR Renography

Computer 62

Louisa Bokacheva1, Henry Rusinek1, Keyma Prince1, Manmeen Kaur1, Thomas Diflo1, Devon John1, Judith Benstein1, Laura Barisoni-Thomas1, Vivian Lee1

1New York University School of Medicine, New York, USA

Dynamic contrast-enhancement MR imaging of the kidneys (MR renography) was used to evaluate patients with normally functioning renal transplants and with transplants during dysfunctional episodes caused by acute tubular necrosis and mild rejection. Contrast concentration versus time curves for renal cortex and medulla were evaluated. The maximum cortical concentration was shown to be significantly lower in ATN cases than in normal or rejected kidneys. The cortical and medullary concentrations at 120 s after the start of acquisition were also significantly lower in kidneys with ATN than in normal or rejected kidneys. The differences between rejected and normal kidneys were insignificant. These findings suggest that MR renography can be used to elucidate the nature of the renal transplant dysfunction.

 

15:00         3685.     Glomerular Filtration Rate Measurements by Dual-Injection MR Renography

Computer 62

Jeff Lei Zhang1, Henry Rusinek1, Louisa Bokacheva1, Qun Chen1, Pippa Storey1, Chekema Prince1, Vivian S. Lee1

1New York University, New York, New York, USA

Dual-injection MR renography has been proposed as an improved diagnostic marker of renovascular disease. Technical challenges include optimal split of one dose for two injections and appropriate analysis of the second renography dataset. Monte Carlo simulation showed that with overall dose of 12 ml 6-8 ml should be used for the second injection, and with dose1 of 4 ml, standard deviation of GFR1-GFR2 was less than 5.1 ml/min. For patients without RAS, GFR1 and GFR2 have a high correlation coefficient R2 = 0.81, and for 30 cases (out of 40) the difference (GFR1 – GFR2) was within [-10, 10] ml/min.

 

15:30         3686.     MR Diffusion Tensor Imaging of the Kidney with Parallel Imaging – Initial Clinical Experience

Computer 62

Mike Notohamiprodjo1, Christian Glaser1, Karin Anna Herrmann, Ulrike Attenberger, Stefan Schoenberg, Maximilian Reiser, Henrik Michaely

1University Hospitals Munich, Munich, Germany

The purpose of this study was to evaluate the feasibility of MR-Diffusion Tensor Imaging (DTI) of the kidney with integrated parallel imaging in volunteers and patients with various renal diseases.

10 volunteers and 27 patients with various renal pathologies underwent MR-DTI. MR-DTI allows a good discrimination between cortex and medulla and visualization of renal architecture alterations, e.g. by tumors or parenchymal disease. Differentiation of simple cysts, cystic and solid renal cell cancer was possible. The results suggest that MR-DTI with integrated parallel imaging may be a useful tool to study and monitor renal ultrastructure.

 

 

 

Hyperpolarized Gas Lung MRI

Hall D                                   Monday 14:00-16:00                                                                                                                                             

14:00         3687.     Lung Ventilation Mapping with Bolus Inhalation of He-3 and Dynamic Projection He-3 MRI Using I-HYPR Reconstruction

Computer 63

Ryan Cullen Lipscomb1, Rafael Louis O'Halloran1, James H. Holmes1, Sean B. Fain1

1University of Wisconsin, Madison, Wisconsin, USA

Rapid 2D hyperpolarized He-3 MRI with projection and iterative highly constrained back-projection (I-HYPR) reconstruction was applied to dynamic imaging of a compact inhaled bolus in a healthy human volunteer at a temporal resolution of 54ms. High resolution upslope and arrival time parametric maps were calculated from the acquired time series data, illustrating and quantifying regional differential ventilation. This technique could prove valuable in assessment and treatment planning for chronic obstructive lung diseases such as cystic fibrosis and asthma.

 

14:30         3688.     Highly Constrained Backprojection (HYPR) for 3He-MRI Spontaneous Breathing and Insufflation Protocols in Rats

Computer 63

Katarzyna Cieslar1, Achraf Al Faraj1, Vasile Stupar1, Sophie Gaillard1, Yannick Cremillieux1

1Creatis-LRMN, UMR CNRS, Université Lyon 1, LYON, France

High temporal resolution is particularly important in small animals studies due to high breathing rates of rodents. Angular undersampling of radially acquired data can increase the temporal resolution but results in poor image quality. HYPR reconstruction can be used to preserve high image SNR despite undersampling. We present the application of HYPR to 3He imaging of rats lungs. Visualisation of respiratory dynamics during insufflation and spontaneous breathing protocol was performed.

 

15:00         3689.     Hyperpolarized-Gas Lung Imaging Using a Single-Shot Spiral Acquisition

Computer 63

Hao Tan1, Weitian Chen1, Peng Hu1, G. Wilson Miller1, Talissa A Altes1, Jaime F Mata1, Eduard E de Lange1, Gordon D Cates1, Ray F. Lee2, Craig H. Meyer1, John Mugler III1

1University of Virginia, Charlottesville, Virginia , USA; 2New York University, New York, New York, USA

Hyperpolarized-gas MRI using 3He can provide quantitative information about lung structure and function. This noninvasive method is of great interest for studying lung diseases such as chronic obstructive pulmonary disease and asthma. In this study, we developed two single-shot spiral sequences towards that goal. In the first sequence, we used a preparation acquisition to obtain a field map before the imaging spiral readout. In the second sequence, we used a single-shot spiral with multiple gradient echoes and reconstructed images iteratively. Both sequences yielded reconstructed images with spatial resolution and image quality comparable to standard GRE images.

 

15:30         3690.     Rapid Motion Mapping of Hyperpolarised Gas Flow Using K-T Subsampling Methods

Computer 63

Xavier Maître1, Shaihan J. Malik2, Pascal Hagot1, Emmanuel Durand1, Luc Darrasse1, David J. Larkman2, Jacques Bittoun1

1CNRS (UMR8081), Univ. Paris-Sud, Orsay, France; 2Robert Steiner MRI Unit, London, UK

Hyperpolarised helium-3 imaging allows visualising airways during inhalation of the gas. Time-of-flight approaches have been developed to enable the high temporal resolution required to track the gas motion through the human airways with true 10 ms temporal resolution. The method is valid as long as the flow velocity remains constant over the total acquisition time. To suite physiological respiratory conditions, a 4-fold k-t undersampling of the dynamic images was performed and data reconstructed using k-t BLAST. Here, total acquisition times as low as 2.8 s were obtained in a mouth-trachea cast phantom with little loss in signal to noise ratio.

 

Bowel Imaging

Hall D                                   Monday 14:00-16:00                                                                                                                                             

14:00         3691.     Dynamic MRI Evaluation of Small Bowel Peristalsis Pattern Using Software: A Feasibility Study

Computer 64

Sooah Kim1, Christophe ChefdHotel2, Laura Rueff1, Ruth P. Lim1, Vivian S. Lee1

1New York University, New York, New York, USA; 2Siemens Corporate Research, Princeton, New Jersey, USA

Ten patients referred for MR enterography were evaluated at 1.5 T using 2D dynamic steady state free precession sequence. 5 small bowel segments were selected per patient, and outer luminal diameter of each segment was measured manually on each dynamic images. Data were plotted over time. ROIs of same selected bowel segments were defined using semi-automated Fourier based software. Average temporal variance of the intensity values were plotted over time. Data and analysis time from both methods were compared, and both showed paralytic pattern of abnormal segments with inflammatory bowel disease. Normal bowel demonstrated periodic sinusoidal contraction. Analysis time per each patient was 20 minutes for manual and 1 minute for software. MRI assessment of small bowel peristalsis pattern using software provides a rapid assessment in inflammatory bowel disease.

 

14:30         3692.     Factors Influencing Small Bowel Water Content: Fibre Intake, Fasting and Feeding

Computer 64

Eleanor F. Cox1, Caroline L. Hoad1, Luca Marciani1, Robin C. Spiller1, Penny A. Gowland1

1University of Nottingham, Nottingham, UK

A novel MRI method was used to evaluate the effect of fibre content of an evening meal on the next morning’s fasting small bowel water content (SBWC) and to determine the effect on SBWC of switching from a fasting to a fed state. Feeding after overnight fasting caused a significant fall in SBWC, which continued to fall even after gastric emptying had begun. The fibre content of the previous night’s meal had no significant effect on SBWC measured the following morning. This important data will help understand the effects of fasting and feeding on the absorption and secretion of water in the small bowel.

 

15:00         3693.     Dynamic Contrast Enhanced MRI Evaluation of Small Bowel Crohn's Disease: A Correlation with Histopathologically Quantified Microvascular Density

Computer 64

Shonit Punwani1,2, Manuel Rodriguez-Justo2, Alan Bainbridge1, Enrico De Vita1,2, Rebecca Greenhalgh2, Steve Halligan1,2, Stuart Taylor1,2

1University College London, London, UK; 2University College London Hospital, London, UK

The aim of this study was to assess  quantitative and semi-quantitative in-vivo DCE-MRI parameters in predicting histopathologically quantified small bowel wall microvascular density (MVD) in resection specimens from patients with known ileal Crohn’s disease. In vivo DCE-MRI of disease affected bowel was performed pre-operation. Post surgical small bowel resection specimens were scanned to enable detailed imaging-histopathology matching. Histological sections were taken through the area of bowel corresponding to the DCE-MRI images. Quantitation of mural microvascular density (MVD) was performed with CD34 staining. DCE-MRI determined slope of enhancement was found to be strongly negatively correlated with MVD. SoE measurements may have potential in assessing disease and monitoring anti-angiogenic therapy in patients with Crohn’s disease affecting small bowel.

 

15:30         3694.     Diffusion-Weighted Imaging in the MR Evaluation of Acute Abdominal Pain in Pregnancy

Computer 64

Jesse L. Wei1, Martin P. Smith1, Neil M. Rofsky1, Ivan Pedrosa1

1Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA

Assessment of acute abdominal and pelvic pain in pregnancy is a challenge that is being addressed by the use of non-contrast MR imaging, including motion-insensitive T2W single-shot fast spin echo for anatomic assessment of structures; and T1W in-and-out of phase, T2W fat-suppressed, and time of flight imaging for characterization of structures based on intrinsic tissue contrast, flow, and susceptibility. We retrospectively analyze the utility of diffusion-weighted imaging as an additional imaging technique to provide another form of image contrast. We find that diffusion weighted images (b=1000) demonstrate increased signal intensity in 5 of 7 inflamed appendices in a population of 37 patients.

 

Body Diffusion & Whole Body Imaging

Hall D                                   Monday 14:00-16:00                                                                                                                                             

14:00         3695.     Respiratory Gated Body Diffusion Weighted Imaging (DWI) Avoiding Prolongation of Scan Time: Tracking Only Navigator Echo (TRON) Technique: Improvement for High B Value DWI

Computer 65

Tomohiko Horie1, Tarou Takahara, Tetsuo Ogino, Tomoyuki Okuaki, Masatoshi Honda1, Isao Muro1, M.V. Cauteren, Yutaka Imai1

1Tokai University School of Medicine, Isehara, Japan

High b value DWI uses a long TE, which results in poor tracking due to increased time lag between navigator and slice excitation. Two software developments have recently been introduced. In this study, we investigated image quality and scanning time using the new TRON version at high b value. Image quality of new TRON was comparable to RT. Relative scanning time to FB was 104% with TRON and 272% with RT. The use of TRON concept and reduction of time lag in navigator sequence allows us practical high b value DWI in a short scan time.

 

 14:30         3696.     Combination of High-B-Value Diffusion-Weighted MRI and MR Cholangiopancreatography as the Optimal Non-Invasive Modality for Diagnosis of Pancreatic Adenocarcinoma [Not Available]

Computer 65

Hiroki Haradome1, Akihisa Nakamura1, Shinju Suzuki1, Nobuaki Matumoto2, Toshiaki Nitatori1, You Atomi2

1Kyorin University School of Medicine., Mitaka, Tokyo, Japan; 2Kyorin University School of Medicine, Mitaka, Tokyo, Japan

Although contrast-enhanced dynamic multi-detector-CT have evolved as the mainstay for pancreatic cancer detection and staging, non-invasive modalities are desired for screening in risk groups of the pancreatic cancer, in particular. Both high-b-value diffusion-weighted MRI (DWI) and MR cholangiopancreatography (MRCP) is non-invasive modalities for detecting pancreatic cancer with a high sensitivity and specificity. We evaluated the utility of combination of DWI and MRCP for diagnosis of pancreatic adenocarcinoma. Combination of DWI and MRCP was the optimal non-invasive modality for diagnosis of pancreatic adenocarcinoma without radiation exposure and contrast agent.

 

15:00         3697.     Prospective Comparison Multi Contrast with Diffusion Weighted Imaging Whole Body MRI, Whole Body PET-CT and Whole Body CT for Staging Advanced Melanoma

Computer 65

valerie laurent1,2, isabelle dufour claude3, pierre olivier1, pierre andre vuissoz, olivier bruot1, denis regent1, jacques felblinger2

1brabois hospital, vandoeuvre les nancy, France; 2H.Poincare university, vandoeuvre les nancy, France; 3general electric health care, BUC, France

Prospective study to compare multicontrast with DWI whole body MRI, whole body PET CT, whole body CT for staging advanced melanoma and to evaluate benefits of DWI sequence in addition oncologic MRI protocol. 38 patients were examined using multicontrast whole body MRI (STIR,T1w after contrast and DWI).The same day, whole body PET-CT et whole body CT were performed. Mc wb MRI with DWI was the most sensitive to detect lesions compared to PET CT and CT. The DWI permits to detect 20% supplementary lesions.  The wb DWI is required in addition to T2w and T1w for oncologic whole body MRI

 

15:30         3698.     High Resolution Whole-Body MRI Applications at 1.5 Tesla and 3 Tesla: A Comparative Study

Computer 65

Gerwin P. Schmidt1, Bernd J. Wintersperger, Anno Graser, Andrea Baur-Melnyk1, Maximilian F. Reiser, Stefan O. Schoenberg

1University Hospitals Munich, Munich, Germany

WB-MRI is feasible at 3 Tesla and has comparably good image quality to 1.5 Tesla. Yet, 3 Tesla whole-body MRI shows significantly more artifacts, but with only mild to moderate impact on image assessment. Overall scan time is further reduced at 3 T with the use of PAT at constant image resolution. 

 

 

 

Iron Effects in Hepatic Imaging

Hall D                                   Monday 14:00-16:00                                                                                                                                             

14:00         3699.     High Speed Multiple Echo Acquisition (HISTO): A Rapid and Simultaneous Assessment of Fat and Iron Content in Liver by 1H-MRS

Computer 66

Nashiely Pineda-Alonso1, Qin Xu1, Puneet Sharma2, Diego Martin3, Xiaoping Hu1

1Emory University, Atlanta, USA; 2Emory Clinic, Atlanta, USA; 3Emory University. School of Medicine, Atlanta, USA

Proton MR Spectroscopy (1H MRS) offers a means for noninvasively determining hepatic lipids (HL) and provides acceptable spectral resolution and high sensitivity even with low amounts of HL. 1H-MRS is also used to accurately quantify the iron overload in the liver. In this work, we introduce a technique that allows the rapid, accurate and simultaneous assessment of fat and iron content which could be applied for single breath hold liver MRS. The feasibility and accuracy of this technique has been demonstrated experimentally in phantoms and applied to patients with fatty liver disease.

 

14:30         3700.     Effect of Superparamagnetic Iron Oxides on Hepatic Apparent Diffusion Coefficient at 3T in Human Subjects with Chronic Liver Disease

Computer 66

Masoud Shiehmorteza1, Chad Andrew Kohl1, Sameer M. Mazhar1, Takeshi Yokoo1, Nicholas Pinto1, Richard Znamirowski Znamirowski1, Lillian O. Pacheco1, Michael S. Middleton1, Claude B. Sirlin1

1Liver Imaging Group, San Diego, California , USA

Iron accumulation may occur in chronic liver disease and by shortening T2* may alter tissue ADC values. To assess the potential effect of intrahepatic iron on ADC measurements, we compared the ADC values at 3T in 15 human subjects with chronic liver disease before and after superparamagnetic iron oxide (SPIO) administration. We found that administration of exogenous iron causes a mild but statistically significant elevation in hepatic ADC. We speculate that endogenous iron may have a similar effect and may modify the relation between ADC and fibrosis stage in chronic liver disease.

 

15:00         3701.     Safety Assessment of Double-Contrast MR Imaging of Liver Disease

Computer 66

Chad Andrew Kohl1, Sameer M. Mazhar1, Takeshi Yokoo1, Alyssa D. Chavez1, Nicholas Pinto1, Lillian O. Pacheco1, Jennifer Berry1, Zana Parman2, Tarek Hassanien2, Joel Lavine2, Jeffrey Schwimmer2, Claude B. Sirlin1, Michael Simca Middleton1

1Liver Imaging Group, San Diego, California , USA; 2UCSD, San Diego, California , USA

Double-contrast (SPIO/Gd) enhanced MR imaging has been used to assess hepatocellular carcinoma and liver fibrosis and may be more accurate for characterization of liver nodules than single-contrast MR imaging. Although each of these types of contrast agents are individually FDA-approved for MR imaging, their sequential use is not FDA-approved. Our aim is to assess the safety of sequential double-contrast MR imaging in patients with liver disease. Based on prospective data from 56 subjects there is no greater risk with sequential use of Feridex® and Magnevist® than with individual use of either agent alone.

 

15:30         3702.     Spleen R2 and R2* in Iron Overloaded Patients with Sickle Cell Disease and Thalassemia Major

Computer 66

Casey John Brewer1, Thomas D. Coates1, John C. Wood1

1Childrens Hospital Los Angeles, Los Angeles, California , USA

Many sickle cell disease (SCD) and thalassemia major (TM) patients require chronic blood transfusions that result in massive iron overload of their organ tissues.  MRI has been used to quantify organ iron but little study has been done on the spleen.  We quantified splenic iron in SCD and TM patients by retrospectively analyzing their hepatic MR scans.  Splenic R2 was attenuated relative to R2* and SCD patients loaded more iron into their spleens than TM patients.  It is concluded that splenic R2 and R2* have a different relationship than do liver R2 and R2* and that the spleen is a major site of iron loading in SCD but not TM patients.

 

Hepatobiliary

Hall D                                   Tuesday 13:30-15:30                                                                                                                                             

13:30         3703.     Perfusion MRI of the Whole Liver Using 4D Thrive: Feasibility of Focal Liver Lesion Characterization Using Parametric Maps

Computer 59

Kenneth Coenegrachts1, Johan Ghekiere1, Vincent Denolin2, Gabriele Beck3, Gwen Hérigault3, Marc Haspeslagh1, Peter Daled1, Shandra Bipat4, Jaap Stoker4, Hans Rigauts1

1AZ St.-Jan AV, Brugge, Belgium; 2Philips Medical Systems, Benelux, Belgium; 3Philips Medical Systems, Best, Netherlands; 4Academic Medical Center, Amsterdam, Netherlands

In this preliminary study, the presented 4D THRIVE sequence seems feasible for perfusion-based T1w CE-MRI and allows calculation of parametric maps. The 4D THRIVE sequence seems promising for the qualitative differentiation of malignant and benign focal liver lesions using parametric maps. Although T1w CE-MRI has been used for perfusion imaging of the liver this technique remains developmental and the best measurement method is still to be determined. Once the methodology is established, rigorous multi-observer studies will be required to validate perfusion MRI and determine its impact on the ability to differentiate malignant from benign liver lesions.

 

14:00         3704.     SPIO-Enhanced FLAIR Echo-Planar Imaging in the Depiction of Hepatic Malignant Tumors: Comparison with T2-Weighted Fast Spin-Echo and T2*-Weighted Fast Field-Echo Imaging

Computer 59

Yoshihiko Fukukura1, Takuro Kamiyama, Ryutaro Higashi, Koji Takumi, Toshikazu Shindo, Masayuki Nakajo

1Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan

SPIO-enhanced echo-planar FLAIR images showed higher accuracy in the detection of hepatic malignant tumors.

 

14:30         3705.     Usefulness of Superparamagnetic Iron Oxide-Enhanced T1-Weighted Echo-Planar MR Imaging for Assessment of Positive Enhancement in Hepatic Hemangioma [Not Available]

Computer 59

Nagaaki Marugami1, Satoru Kitano1, Shinji Hirohashi2, Junko Takahama1, Kimihiko Kichikawa1

1Nara Medical University, Kashihara, Japan; 2Gyoumeikan Hospital, Osaka, Japan

SPIO-enhanced T1-weighted Echo-plannar MR imaging is useful in diagnosis of hepatic hemangioma with the finding of positive enhancement.

 

15:00         3706.     Variable Performance of Chemical Shift-Based Multipoint Water-Fat Separation MRI and Its Impact on the Diagnosis of Fatty Liver

Computer 59

Hyeonjin Kim1, Sara E. Taksali, Sylvie Dufour, Douglas Befroy, T Robin Goodman1, Kitt Falk Petersen, Gerald I. Shulman, Sonia Caprio, R Todd Constable1

1Yale University School of Medicine, New Haven, Connecticut, USA

In this report we address the variable performance of chemical shift-based multipoint water-fat separation MRI and its influence on the diagnosis of fatty liver in 28 humans by using 1H-MRS as a reference, 2-point Dixon and 3-point IDEAL. Our results demonstrate that the performance of multipoint water-fat separation MRI significantly depends on the choice of sampling strategy, post-data processing algorithm and pulse sequence. Therefore, to minimize errors in the diagnosis of fatty liver using multipoint water-fat separation MRI, it may be necessary to establish a cutoff fat content for normal liver specific to each imaging protocol¡¯s sequences and sequence parameters.

 

13:30         3707.     Dynamic Gadolinium-Enhanced Liver Imaging Using LAVA Dual Echo with Water Reconstruction

Computer 60

Russell Norman Low1,2, Scott Boles2, Neeraj Panchal2

1Sharp and Children's MRI Center, San Diego, California , USA; 2San Diego Imaging, San Diego, California , USA

LAVA-IDEAL generates water images from a dual echo 3D FSPGR acquisition using a 2-point Dixon reconstruction algorithm. Dynamic liver imaging with LAVA-IDEAL during the arterial and portal venous phases is characterized by nearly perfect separation of fat and water signal, images with high contrast, minimal artifacts and excellent depiction of liver lesions.

 

14:00         3708.     Hepatic Steatosis Results in a Reduction in the Apparent Diffusion Coefficient (ADC) of Liver Parenchyma

Computer 60

Oliver Wignall1, Erica Scurr1, David Collins2, Choon-Hua Thng3, Dow-Mu Koh2

1Royal Marsden Hospital, Sutton, UK; 2Institute of Cancer  Research, Sutton, UK; 3National Cancer Centre, Singapore, Singapore

This study compares the ADC values of liver parenchyma in areas with and without fatty infiltration as determined by in-phase and opposed-phase T1-weighted MR imaging. The mean ADC of areas of fatty infiltration is significantly lower than that of normal liver. A linear relationship was established between ADC and the percentage of fat infiltration as estimated by the ratio of in-phase and opposed-phase signal intensities in steatotic liver. This has implications for DWI assessment of diffuse liver disease.

 

14:30         3709.     Noninvasive Evaluation of Nonalcoholic Fatty Liver Disease (NAFLD) Using 1H and 23Na Magnetic Resonance Imaging and Spectroscopy in a Rat Model

Computer 60

Paige Nicole Hopewell1,2, Navin Bansal1

1Indiana University School of Medicine, Indianapolis, Indiana, USA; 2Purdue University, West Lafayette, Indiana, USA

With increasing prevalence of the metabolic syndrome, non-alcoholic fatty liver disease (NAFLD) is now the most common chronic liver disease in humans. This study employed extensive lipid profiling via 1H MRS to demonstrate temporal changes in lipid content, resolving 8 lipid resonance peaks plus water in vivo, with water- and fat-suppressed 1H MRI. Single-quantum- (SQ) and multiple-quantum-(MQF) filtered 23Na MRI were employed to evaluate cellular energy status as NAFLD progressed in a MCDD rat model.

 

15:00         3710.     Overestimation of Liver Fat Content in Fast Dixon-Based MRI Method Compared with Multi-Voxel MR Spectroscopy Quantification

Computer 60

Paul E. Sijens1, Mireille A. Edens1, Roy Irwan1

1UMCG, Groningen, Netherlands

A recently published Dixon-based MRI method for quantifying liver fat content using dual-echo breath-hold gradient echo imaging was validated by phantom experiments and compared with results of biopsy in two patients [Radiology 2005;237:1048-1055]. We applied this method in ten healthy volunteers and compared the outcomes with the results of MR spectroscopy (MRS), the gold standard in quantifying liver fat content. Novel was the use of spectroscopic imaging yielding the variations in fat content across the liver rather than a single value obtained by single voxel MRS. Compared with results of MRS, liver fat content according to MRI was too high in nine subjects (range 3.3-10.7% vs. 0.9-7.7%) and correct in one (21.1 vs. 21.3%). Furthermore, in one of the ten subjects the MRI fat content according to the Dixon-based MRI method was incorrect due to a (100-x) versus x percent lipid content mix-up. Despite systematic overestimation of liver fat contents by MRI, Spearman's correlation between the (in 1 case adjusted) MRI liver fat contents with MRS was high (r = 0.927, P < 0.001). The problem with the Dixon-based MRI method for the assessment of liver fat content, is that, at the lower end range, liver fat content is systematically overestimated by approximately 3%.

 

13:30         3711.     Rapid Evaluation of Liver Fat Content Using In-Out-Phase Imaging in Nonalcoholic Fatty Liver Disease

Computer 61

Ronald Borra1,2, Sakari Salo1, Kirsti Dean1, Riikka Lautamäki2, Pirjo Nuutila2, Markku Komu1, Riitta Parkkola1,2

1Turku University Hospital, Turku, Finland; 2University of Turku and Turku University Hospital, Turku, Finland

This study shows the possibilities for liver fat content (LFC) quantification with in-out-phase imaging in patients with type 2 diabetes, at high risk for nonalcoholic fatty liver disease (NAFLD). Signal intensity differences between in-phase and out-phase images were correlated linearly with 1H MRS measurements of LFC (P<0.001, r=0.94) and provided a cut-off point at 5.1%, the normal upper limit for LFC. Our findings suggest that in-out-phase imaging can be used for rapid and reliable discrimination between normal or increased LFC in patients with NAFLD.

 

14:00         3712.     Human Liver Transplant Graft Steatosis: Evaluation with MRI

Computer 61

David John Lomas1, Kieren G. Hollingsworth1, Richard T. Black1, Jane C. Smith1, Toby Prevost2, Chris J. Watson1, Neville V. Jamieson1, Graeme J. Alexander1, Alexander E. Gimson1

1University of Cambridge & Addenbrooke's Hospital, Cambridge, UK; 2University of Cambridge, Cambridge, UK

Steatosis in donor liver grafts adversely affects outcome in human transplantation. This study investigates whether rapid MRI steatosis quantification in ex-vivo grafts, immediately prior to transplantation, correlates firstly with the currently used surgical “eyeball” and subsequent pathology “time zero” biopsy assessment; and secondly with the biochemical parameters measured in the first week post transplant that reflect early graft performance. Thirty nine grafts were examined and MRI quantification correlated significantly with the other two assessments but was the only one of the three to correlate significantly with any of the serum markers of early graft performance.

 

14:30         3713.     Quantification of Hepatic Steatosis with MRI: Correction for Bias from Noise and T1

Computer 61

Chia-Ying Liu1,2, Charles A. McKenzie2, Huanzhou Yu3, Jean H. Brittain4, Scott Brian Reeder1

1University of Wisconsin-Madison, Madison, Wisconsin, USA; 2University of Western Ontario, London, Canada; 3GE Healthcare, Menlo Park, California , USA; 4GE Healthcare, Madison, Wisconsin, USA

Quantification of hepatic steatosis is a significant unmet need for the diagnosis and treatment monitoring of patients with non-alcoholic fatty liver disease. MRI is capable of separating water and fat signals to quantify steatosis. Unfortunately, the non-zero mean noise in magnitude images and confounding T1 effects can lead to incorrect estimation of the true fat fraction. We demonstrate two approaches to reduce noise bias: magnitude discrimination and phase-constrained reconstruction, and two methods to reduce T1 bias: small flip angle and dual flip angle method. Bias on fat-fraction estimates was minimized using these methods.

 

 15:00         3714.     Liver Steatosis Quantification Using MRI: A Prospective Comparative Study with Liver Biopsy

Computer 61

nicolas mennesson1, Jérôme Dumortier1, Sophie Cavassila2, Olivier Beuf2, Jean-Yves Scoazec3, Frank Pilleul,12

1Hospices Civils de Lyon, Lyon, France; 2INSA-Lyon, Université Lyon 1, Villeurbanne, France; 3Faculté de médecine RTH Laennec, Lyon, France

The diagnosis of steatosis does have important therapeutic implications, because active management of obesity and a reduction in steatosis may improve liver injury and decrease the progression of fibrosis. Double-echo imaging (DEI) such as simple method have been used in order to substitute liver biopsy which is the gold standard. For this study, forty patients with suspected chronic liver diseases were prospectively investigated by MR imaging and liver biopsy. The fat/water ratio had a positive correlation with steatosis grade on liver biopsy (p < 0.0001), the coefficient of linear regression corresponding to r = 0.798. So, Fat/Water ratio (cutoff value ¡Ý at .93) revealed liver steatosis defined by the presence of equal or more 20 % of intracellular lipids with a sensitivity of 93 % and a specificity of 86 %.

 

 13:30         3715.     Characterization of Liver Fibrosis Using Fat-Suppressed Ultrashort TE (FUTE) Imaging and Multipoint Water-Fat Separation MRI in Patients with Hepatitis C Virus (HCV)-Induced Liver Fibrosis

Computer 62

Hyeonjin Kim1, Matthew D. Robson2, Maolin Qiu1, Jinghua Wang1, Joseph K. Lim, Philip S. Murphy3, R Todd Constable1

1Yale University School of Medicine, New Haven, Connecticut, USA; 2John Radcliffe Hospital, Oxford, UK; 3Pfizer, Sandwich, UK

The feasibility of ultrashort echo time (UTE) imaging in assessing liver fibrosis was explored in patients with different stages of hepatitis C virus (HCV)-induced liver fibrosis.  As hepatic steatosis and concomitant iron overload are common features in many chronic liver diseases, the quantification of hepatic fat content and T2* mapping are also performed and their effect on the quantification of short T2 components is addressed.  Our results suggest that fat-suppressed UTE (FUTE) imaging may potentially provide a means of non-invasively discriminating the end stage of liver fibrosis from its milder forms in the presence of steatosis and/or iron overload.

 

14:00         3716.     Correlation Between Different Stages of Hepatic Fibrosis and in Vivo Metabolic Profile by 1H Magentic Resonante Spectroscopy

Computer 62

Beatriz Martínez-Granados1, M. Carmen Carmen Martínez-Bisbal1,2, Daniel Monleón3, Luís Martí-Bonmatí4, José Manuel Manuel Rodrigo3, Juan del Olmo3, Antonio Ferrández3, Bernardo Celda1,2

1Universitat de Valencia, Burjassot, Spain; 2ISC III, Burjassot, Spain; 3Hospital Clínico Universitario, Valencia, Spain; 4Hospital Universitario Dr. Peset, Valencia, Spain

The aim of this study is to verify the potential clinical applications of in vivo liver 1H-MRS metabolic alterations for improving the diagnosis of different liver fibrosis stage. MRS 1.5T (SV at TE=136 ms) studies were performed in 50 patients with clinical fibrosis. Different resonances (lipids, choline, TMAO and glucose) were assigned and identified using ex vivo HR-MAS (11T) and literature data. Statistical significant differences between (-CH3 lipid)/H2O and (glucose+-CH=CHCH2- lipid+glycogen)/H2O ratios and the four fibrosis stages were found. The in vivo liver 1H-MRS profiles and their correlation with fibrosis adds non-invasively quantitative metabolic information to liver pathology diagnosis.

 

14:30         3717.     Effect of Autologous Bone Marrow Cell Infusion Therapy in Patient with Liver Cirrhosis on Ferucarbotran-Enhanced MR Imaging: A Preliminary Report

Computer 62

Mi-Suk Park1, Ja Kyung Kim

1Yonsei University, Severance Hospital, Seoul, Republic of Korea

Our study is an initial, preliminary report about the effect of ABMI therapy in the patients with liver cirrhosis on ferucarbotran-enhanced MR Imaging. There was a gradual reduction of SPIO uptake after ABMI with increase of liver volume and serum albumin level, which might reflect the progenitor cell proliferation and reduction in Kupffer cell. However, further investigation with contrast agents tagging with bone marrow cells may be needed to evaluate the precise effect of ABMI therapy in the patients with liver cirrhosis.

 

15:00         3718.     Non-Invasive Diagnosis of Liver Fibrosis - Comparison Between MR Elastography and Supersonic Imaging in an Animal Study

Computer 62

Najat Salameh1, Jean-Luc Gennisson2, Benoit Larrat2, Thomas Deffieux2, Michael Tanter2, Ralph Sinkus2, Bernard Edgard Van Beers1, Mathias Fink2

1Université Catholique de Louvain, Brussels, Belgium; 2Laboratoire Ondes et Acoustiques, Paris, France

In this study, we validate the Supersonic Shear Imaging method, by comparing the elasticity measurements obtained with SSI to those obtained with MRE in a model of dietary steatohepatitis in the rat. The elastography measurements were correlated to the percentage of fibrosis obtained at morphometry.

 

13:30         3719.     Quantification of SPIO Enhancement Measured by T2 and T2* Mapping in Chronic Liver Disease: A Preliminary Report
[Not Available]

Computer 63

Yong Eun Chung1, Mi-Suk Park1, Eun Ju Kim, Myoung Soo Kim1, Hua-Sun Kim1, Myeong-Jin Kim1, Jin-Young Choi1, Ki Whang Kim1

1Yonsei University Health System, Seoul, Republic of Korea

This study evaluate feasibility of T2 and T2 mapping on pre- and post-contrast multi echo fast field echo sequence in chronic liver disease patient.

 

14:00         3720.     MR Imaging Findings in Patients with Hereditary Hemorrhagic Telangiectasia and Liver Involvement

Computer 63

Guenther K. Schneider1, Alexander Massmann2, Miles A. Kirchin3, Roland Seidel1, Peter Fries1, Urban W. Geisthoff4, Arno Buecker1

1Saarland University Hospital, Homburg/Saar, Germany; 2Saarland University Hospital,, Homburg/Saar, Germany; 3Bracco Imaging S.p.A., Milan, Italy; 4Hospitals of the City of Cologne, Cologne, Germany

Hereditary hemorrhagic telangiectasia (HHT) also known as Rendu-Osler-Weber disease is an autosomal-dominant inherited vascular disorder associated with mucocutaneous, pulmonary, cerebral and visceral arteriovenous malformations. Hepatic affection of HHT results in a wide spectrum from discrete changes of the liver parenchyma and hepatic vessels to high morbidity and mortality due to right heart insufficiency. The study shows the variety of different HHT-related findings in the liver on magnetic resonance imaging and magnetic resonance angiography: hepatomegalia, nodular hyperplastic changes of the liver parenchyma, dilated tortuous intrahepatic vessels, increased hepatic artery and portal vein diameter as well as right heart insufficiency.

 

14:30         3721.     T1-Weighted DCE MRI with Gd-EOB-DTPA as a Liver Function Test: A Comparison of Two Methods for Deconvolutional Analysis

Computer 63

Henrik Nilsson1, Anders Nordell2, Lena Douglas2, Roberto Vargas3, Eduard Jonas1, Lennart Blomqvist3

1Karolinska Instiutet, Stockholm, Sweden; 2Karolinska University Hospital, Stockholm, Sweden; 3Institution for Molecular Medicine and Surgery Karolinska Institutet, Stockholm, Sweden

The aim of this study was to assess the feasibility to use dynamic T1-weighted Gd-EOB-DTPA-enhanced MRI for the evaluation of segmental liver function in 20 healthy human volunteers. Hepatic Extraction Fraction (HEF), earlier described and used in hepatobiliary scintigraphy, was chosen as marker of hepatocyte function. For deconvolutional analysis (DA), Fourier transforms with an appended tail and Singular Value Decomposition (SVD) were used. The results obtained with the two methods for DA were compared. We found that it is possible to calculate HEF on a segmental level, and that the two methods yields similar results without significant differences.

 

15:00         3722.     Evaluation of Superparamagnetic Iron Oxide (SPIO) Particles for MR Imaging of Nonalcoholic Steatohepatitis (NASH)
[Not Available]

Computer 63

Akihiro Tanimoto1, Kengo Tomita1, Rie Irie1, Koichi Oshio1, Sachio Kuribay1

1Keio University School of Medicine, Tokyo, Japan

To determine whether SPIO-enhanced MRI can help to detect NASH, we evaluated 19 patients with nonalcoholic fatty liver disease (NAFLD). Liver biopsy proved ten of 19 patients were definitive NASH.  MRI consisting of T2-FSE, T2*-GRE, and EPI was performed prior to biopsy.  Relative signal decrease [%T2 and %T2*] caused by SPIO were smaller in NASH group than in not NASH group.  The time constant &[tau] from exponential approximation of signal decay on EPI was larger in NASH group than in not NASH group.  SPIO-enhanced MRI would be a reliable tool to identify NASH patients among the patients having NAFLD.

 

13:30         3723.     Depiction of Non-Dilated Intrahepatic Bile Duct by High Spatial Resolution 3D MR Cholangiography Using SPACE at 3 T; Comparison with 1.5 T in Healthy Volunteers [Not Available]

Computer 64

Shigeki Arizono1, Hiroyoshi Isoda1, Yoji Maetani1, Yuusuke Hirokawa1, Kotaro Shimada1, Yuji Nakamoto1, Kaori Togashi1

1Kyoto University Graduate School of Medicine, Kyoto, Japan

SPACE is a new technique that could overcome SAR problem on 3D TSE sequence at 3T by using variable refocusing FA, while maintaining better SNR. Applying the SPACE technique at 3T, high spatial resolution 3D MRC can be obtained without running into SAR problem. In this presentation, we described the superiority of 3D MRC with SPACE at 3 T over MRC with conventional constant FA at 3T or MRC at 1.5T. In addition, we showed that high resolution 3D MRC with SPACE at 3T allows high-quality images of biliary tract, and has the ability to depict non-dilated intrahepatic bile ducts.

 

14:00         3724.     Navigator-Triggered Prospective Acquisition Correction (PACE) Technique vs. Conventional Respiratory-Triggered Technique for Free-Breathing 3D MRCP: Prospective Comparative Study Using Healthy Volunteers

Computer 64

Satoru Morita1, Eiko Ueno1, Kazufumi Suzuki1, Haruhiko Machida1, Mikihiko Fujimura1, Shinya Kojima1, Masami Hirata1, Takahiro Ohnishi2, Chiaki Imura2

1Tokyo Women's Medical University Medical Center East, Tokyo, Japan; 2Siemens-Asahi Medical Technologies, Tokyo, Japan

This study sought to confirm the superiority of navigator-triggered prospective acquisition correction (PACE) technique over the conventional respiratory-triggered (RESP) technique. This has been perceived experimentally, but  without definite evidence, for free-breathing 3D MRCP. Images from free-breathing 3D turbo spin-echo MRCP using both PACE and RESP techniques were prospectively performed on 25 healthy volunteers. Qualitative and quantitative analyses of contour sharpness index both revealed the image quality of PACE technique to be significantly better than RESP. The superiority of PACE to conventional RESP for free-breathing 3D MRCP with regard to the image quality was confirmed.

 

14:30         3725.     Respiratory Triggered High-Spatial Resolution T1-Weighted MR Imaging of Liver and Biliary Tree in the Hepatobiliary Phase

Computer 64

Patrick Asbach1, Carsten Warmuth2, Matthias Rief1, Matthias Taupitz1, Bernd Hamm1, Christian Klessen1

1Charité - Universitaetsmedizin Berlin, Berlin, Germany; 2Siemens Medical Solutions, Erlangen, Germany

Hepatobiliary contrast media have the potential to increase the diagnostic performance of magnetic resonance imaging of the liver. The hypothesis for this study was that respiratory triggered high-spatial resolution images acquired in the hepatobiliary phase provide significantly increased image quality compared to breath-hold images. A quantitative and qualitative analysis was performed in 20 patients comparing a respiratory triggered T1w inversion prepared spoiled gradient echo sequence to a breath-hold T1w spoiled gradient echo sequence. The respiratory triggered high-spatial resolution images provide a significantly increased image quality in comparison to breath-hold images on the expense of extended acquisition time.

 

15:00         3726.     Biliary Anatomy on 3D MRCP Using Free-Breathing Navigator-Triggered Prospective Acquisition Correction: Comparison of Volume-Rendering and Maximum-Intensity-Projection Algorithm

Computer 64

Satoru Morita1,2, Naoko Saito3, Kazufumi Suzuki1, Haruhiko Machida1, Mikihiko Fujimura1, Eiko Ueno1, Norio Mitsuhashi4, Takahiro Ohnishi5, Chiaki Imura5

1Tokyo Women's Medical University Medical Center East, Tokyo, Japan; 2Saiseikai Kurihashi Hospital, Saitama, Japan; 3Boston Medical Center, Boston University School of Medicine, MA, USA; 4Tokyo Women's Medical U

This study sought to compare VR and MIP as postprocessing techniques of 3D MRCP to define biliary anatomies. VR and MIP images of 3D MRCP using a prospective acquisition correction technique for 102 patients were retrospectively evaluated by two radiologists in a blinded fashion independently. Interpretation confidence and the accuracies of each reformation with the reference standard were compared. VR findings agreed with the reference standard findings more often than MIP with regard to cystic duct variation. Mean confidence score was significantly higher with VR than MIP with regard to both cystic duct variation and biliary branching patterns. VR reformation of 3D MRCP defines biliary anatomies more accurately than MIP.

 

13:30         3727.     k-TE GRAPPA for Rapid Abdominal R2* Mapping

Computer 65

Xiaoming Yin1,2, Andrew C. Larson1,2

1Northwestern University, Chicago, Illinois, USA; 2Evanston, Illinois, USA

R2* measurements have proven useful for abdominal imaging applications. The commonly used multiple-GRE (MGRE) sequence collects a train of echoes thereby permitting the reconstruction of images at each TE and subsequent derivation of R2* maps. However, spatial resolution remains to be a challenge to breath-hold requirements. Based upon an extension of k-t GRAPPA parallel imaging methods we recently developed a k-TE GRAPPA approach to reduce MGRE scan times. It has been found that k-TE GRAPPA is an effective parallel imaging method to accelerate MGRE R2*-mapping. It reduced artifact levels and provided more accurate R2* measurements compared to VS and GRAPPA approaches. k-TE GRAPPA offers the potential to reduce breath-hold times and/or increase spatial resolution or coverage.

 

14:00         3728.     Safety of MR Imaging of the Liver with Ferucarbotran: Multicenter Investigation Using Questionnaire Before and After an Examination

Computer 65

Hiromitsu Onishi1, Takamichi Murakami2, Tonsok Kim1, Masatoshi Hori1, Mitsuru Matsuki, Shinji Hirohashi, Yasuharu Imai, Kousuke Sakurai, Yoshifumi Narumi, Hironobu Nakamura1

1Osaka University Graduate School of Medicine, Suita, Japan; 2Kinki University, Osakasayama, Japan

We prospectively investigated the incidence of adverse reactions of ferucarbotran, a superparamagnetic iron oxide contrast agent, using a questionnaire style. Three hundred fifteen patients who underwent ferucarbotran-enhanced magnetic resonance imaging were given a questionnaire asking about the symptoms over a period of 7 days before and after injection of ferucarbotran in order to estimate the false positive adverse reactions. The adverse events to ferucarbotran which were classified as possibly or definitely ferucarbotran related occurred in 14.3%. All of adverse reactions were mild of intensity. Ferucarbotran was considered to be safe in the clinical use at MR imaging of the liver.

 

14:30         3729.     Discrimination of Pancreaticohepatobiliary Cancer and Benign Patients in Presence and Absence of Jaundice and Cholangitis: 1H and 31P NMR Studies of Bile

Computer 65

Lakshmi Bala1, Pratima Tripathi1, Raja Roy1, Gourdas Choudhuri2, Chunni Lal Khetrapal1

1Sanjay Gandhi Post-Graduate Institute of Medical Sciences Campus, LUCKNOW, India; 2Sanjay Gandhi Post-Graduate Institute of Medical Sciences, LUCKNOW, India

1H and 31P NMR quantitative analysis of bile specimens from pancreaticohepatobiliary cancer (n=28) and benign patients (n=20) (with/without jaundice and cholangitis) were carried out for chief biliary constituents viz. total bile acids (TBA), cholesterol (Chol.), phosphatidylcholine (PtC) and inorganic phosphate (Pi). Presence of jaundice and cholangitis significantly lowered biliary constituents (p<0.05 for all) in both benign and malignant patients, possibly due to the down regulation of function of tranporters located at the canalicular side of hepatocytes. Hence, presence of jaundice and cholangitis reduces biliary constituents in bile in benign resulting them indiscriminant with malignant without jaundice and cholangitis.

 

15:00         3730.     Respiratory Self-Gated Phase-Contrast MRI for Free-Breathing Flow Measurements in the Portal Venous System

Computer 65

Ning Jin1, Andrew C. Larson1,2

1Northwestern University, Chicago, Illinois, USA; 2Robert H. Lurie Comprehensive Cancer Center, Chicago, Illinois, USA

Breath hold is commomly needed for abdominal phase contrast (PC) flow measurement to remove the respiratory motion. However, the scan times may be prohibitive for cardiac-gated high-resolution imaging. Also for some ill patients, they may be unable to comply with breath hold commands. Some alternative free-breathing methods may be beneficial. Self-gating approaches with additional central k-space lines sampled to track respiratory motion have been applied in cardiovascular and abdominal imaging with free breathing. In this abstract we developed a respiratory self-gated imaging strategy for free breathing abdominal PC flow measurements and compared this technique to conventional breath-hold PC flow measurement in the portal venous system.

 

Advances in GI & Hepatobiliary Imaging

Hall D                                   Tuesday 13:30-15:30                                                                                                                                             

13:30         3731.     Diffusion Weighted MR Imaging of Gastric Cancer: Comparison with Conventional MRI Sequences

Computer 66

Lei Tang1, Xiao Peng Zhang1, Ying Shi Sun1, Kun Cao1, Jie Li1, Ning Wang1, Fei Sun2

1Beijing Cancer Hospital & Peking University School of Oncology, Beijing, People's Republic of China; 2GE healthcare China, Beijing, People's Republic of China

MRI examinations were performed on 31 patients with gastric cancer. Three diffusion-weighted sequences were designed with different b values. Free water grade was used to evaluate the suppression of content signal in gastric lumen. SNR and SIR of high b-value DWI and conventional MRI sequences were calculated and compared. High b-value DWI could demonstrate signal differences better. The ADCs of gastric cancer were decreased following the increase of b-value. The CNR and SIR of high b-value DWI were higher than that of T1WI and T2WI. DWI can be a supplementary method for conventional MRI examinations to demonstrate gastric cancer better.

 

14:00         3732.     Utility of Ferucarbotran-Enhanced T1-Weighted Spoiled Gradient Recalled Echo MR Images for Hepatic Metastases: A Prospective Comparison with 3.0 T and 1.5T

Computer 66

Masakatsu Tsurusaki1, Keitaro Sofue1, Mototaka Miyake1, Aine Sakurada1, Ukihide Tateishi1, Yasuaki Arai1, Kazuro Sugimura2

1National cancer center, Tokyo, Japan; 2Kobe University, Graduate school of medicine, Kobe, Japan

To prospectively compare the frequency and qualitative efficacy of gring enhancementh on ferucarbotran-enhanced T1-weighted GRE images using 3.0 T to 1.5T for the detection of hepatic metastases. A total of 25 patients with 70 hepatic metastases underwent ferucarbotran-enhanced MR imaging using both 3.0T and 1.5T scanner. The frequency of gring enhancementh in hepatic metastases at 3.0T (74.2%) was significantly (p<0.05) higher than at 1.5T (55.7%) on ferucarbotran-enhanced T1-weighted GRE images. On T1-weighted GRE images, gring enhancementh is shown more frequent at 3.0T than 1.5T. Therefore, it is also helpful sign for characterizing hepatic metastases in ferucarbotran-enhanced MR images.

 

14:30         3733.     Ferucarbotran-Enhanced Magnetic Resonance Imaging in Patients with Hepatic Metastases: Prospective Quantitative and Qualitative Comparison of 3.0 T and 1.5T [Not Available]

Computer 66

Keitaro Sofue1, Masakatsu Tsurusaki1, Mototaka Miyake1, Aine Sakurada1, Ukihide Tateishi1, Yasuaki Arai1, Kazuro Sugimura2

1National Cancer Center Hospital, Tokyo, Japan; 2Kobe University, Graduate School of Medicine, Kobe, Japan

To prospectively compare quantitative and qualitative efficacy of ferucarbotran-enhanced MR imaging using 3.0 T to 1.5T for the detection of hepatic metastases. Using 3.0T, ferucarbotran-enhanced MRI showed higher sensitivity than the images using 1.5T for the detection of hepatic metastases. On ferucarbotran-enhanced MRI using 3.0T, higher SNR and lesion-to-liver CNR were achieved than 1.5T, moreover, the decreasing of motion artifact and the improvement of overall image quality on T2*-weighted GRE images using 3.0T might contribute the higher sensitivity.

 

15:00         3734.     Evaluation of Quantitative Dynamic Contrast Enhanced Pharmacokinetic Parameters with and Without Postprocessing Alignment

Computer 66

Keiko Miyazaki1, David J. Collins1, Dow-Mu Koh1, David Atkinson2, David J. Hawkes2, Martin O. Leach1

1Institute of Cancer Research, Sutton, UK; 2University College London, London, UK

Dynamic imaging in the liver is a major challenge particularly in accounting for mis-alignments and deformation of the liver. In this paper, the effects of mis-alignment effects in a clinical DCE-MRI liver protocol which involved successive full-exhale breath-holds was evaluated by analyzing the pharmacokinetic (PK) parameters with and without post-processing alignment. DCE-MR protocols which are robust to mis-alignments in the organs would assist accurate derivation of quantitative PK parameters which are increasingly used in several clinical setting to monitor disease progression and regression.

 

13:30         3735.     Diagnosis of Liver Metastatic Lesions: Performance of Diffusion-Weighted Imaging Compared to Contrast-Enhanced T1-Weighted Imaging

Computer 67

Andrew D. Hardie1, Mohit Naik1, Elizabeth M. Hecht1, Hersh Chandarana1, Vivian S. Lee1, Bachir Taouli1

1NYU Medical Center, New York, New York, USA

With the recently described risks of gadolinium exposure in patients with poor renal function, optimization of non-gadolinium enhanced sequences is essential. This study compares the accuracy of diffusion-weighted imaging (DWI) compared to Gadolinium-enhanced T1 sequence for diagnosis of liver metastases in patients with primary cancer. Sensitivity of the DWI and Gd-enhanced datasets were both 81% while the specificity was 78% for DWI and 89% for Gd-enhanced T1. This preliminary study demonstrates the potential role of DWI as an alternate method for the assessment of focal liver lesions in oncology patients in whom gadolinium is contraindicated.

  

14:00         3736.     1H MRS of Human Bile in the Differential Diagnosis of Cholangiocarcinoma and Pancreatic Cancer

Computer 67

Tedros Bezabeh1, Omkar B. Ijare1, Nils Albiin2, Urban Arnelo2, Bo Lindberg2, Ian C.P. Smith1

1National Research Council Institute for Biodiagnostics, Winnipeg, Canada; 2Karolinska Institutet, Stockholm, Sweden

Bile is a biofluid of choice for the study of pancreaticobiliary malignancies such as cholangiocarcinoma, gallbladder cancer and pancreatic cancer. In the course of these malignancies, the biochemical composition of bile alters as a result of increased cell turnover. In the present study, the biochemical composition of bile was compared in two pancreaticobiliary malignancies – cholangiocarcinoma and pancreatic cancer, making use of 1H MRS. The study revealed that cholangiocarcinoma patients showed a decrease in biliary biochemicals such as bile salts, phosphatidylcholine and cholesterol compared to the normal reference patients. Furthermore, most of the bile samples showed the absence of some conjugated bile salts and phosphatidylcholine. On the contrary, in pancreatic cancer, biliary lipid components were intact, but a carbohydrate moiety, D-glucuronate, was predominantly observed in the bile.

 

14:30         3737.     Effect of Intravenous Superparamagnetic Iron Oxide on Diffusion-Weighted Imaging

Computer 67

Nagaaki Marugami1, Satoru Kitano1, Shinji Hirohashi2, Megumi Takewa1, Junko Takahama1, Aki Takahashi1, Kimihiko Kichikawa1

1Nara Medical University, Kashihara, Japan; 2Osaka Gyoumeikan Hospital, Osaka, Japan

Superparamagnetic iron oxide injection had significant effects on ADC values. Therefore, only pre-contrast diffusion-weighted images should be used on quantitative ADC studies.

 

15:00         3738.     ROC Comparison Between Diffusion-Weighted MR and PET/CT Imaging to Detect Lymph Node Metastasis from Gastrointestinal Cancer

Computer 67

Hitoshi Kubo1, Masafumi Harada1, Tatsuro Goto1, Masaaki Ikeguchi1, Mayumi Takeuchi1, Hiromu Nishitani1

1University of Tokushima, Tokushima, Japan

The usefulness of diffusion-weighted MR imaging (DWI) to detect lymph node metastasis from the gastrointestinal cancer was evaluated by ROC analysis in comparison with 18F-FDG imaging (PET). We analyzed 21 patients examined both DWI and PET in our Hospital. The sensitivity of DWI was higher but the specificity was lower than those of PET. The ROC analysis showed higher accuracy on DWI than PET, though the variation of individual evaluation on DWI was larger than that on PET depending on the experience of imaging diagnosis by observers.

 

13:30         3739.     Comparison in Functional and Metabolic MR Imaging Findings Between Targeted and Non-Targeted Unresectable Hepatic Tumors Treated with TACE

Computer 68

Ihab R. Kamel1, Josephina A. Vossen, Manon Buijs, Nouha Salibi, David A. Bluemke, Jean-Francois H. Geschwind

1Johns Hopkins Hospital, Baltimore, Maryland, USA

The objective of this study was to compare functional (tumor enhancement and ADC value) and metabolic (Choline concentration) findings in patients with unresectable hepatic tumors treated with TACE. MR Imaging studies were obtained before and after a single TACE treatment in 19 patients with primary or metastatic liver lesions. All targeted tumors had complete loss of the Choline peak, a significant increase in tumor ADC value, and a significant decrease in tumor arterial and venous enhancement, without change in tumor size.  These functional findings precede tumor regression in size, and may be utilized to detect early therapeutic response.

 

14:00         3740.     Characterization of Gastric Cancer with Diffusion-Weighted MR Imaging: Prospective Study in 101 Patients

Computer 68

Xiao Peng Zhang1, Lei Tang1, Ying Shi Sun1, Kun Cao1, Jie Li1, Ning Wang1

1Beijing Cancer Hospital & Peking University School of Oncology, Beijing, People's Republic of China

MRI examinations were performed on 101 patients with gastric cancer. Diffusion-weighted single-shot echo-planar sequences were performed combined with sensitivity encoding technique. Forty-four gastric cancers displayed uniformly high signal; and 46 displayed nonuniform signal on DWI. Ten Borrmann-4 gastric cancers displayed ¡°sandwich¡± sign on DWI, which appeared high signal on mucosa and serosa layers, with a low signal band mediately which indicate muscularis propria. The ADCs of diffuse-type gastric cancers were lower than that of confining-type with statistical significances.

 

14:30         3741.     Hepatocellular Carcinoma: Assessment of Tumor Oxygenation with BOLD MRI

Computer 68

Mohit Naik1, Lorenzo Mannelli1, Hersh Chandarana1, Vivian Lee1, Bachir Taouli1

1NYU Medical Center, New York, New York, USA

In this study we prospectively evaluated the ability of BOLD MRI to assess tumor hypoxia for treated and untreated hepatocellular carcinoma (HCC). Untreated HCC demonstrates significantly higher oxygen uptake (ÄR2*) compared to HCCs post transarterial chemoembolization (TACE) and liver parenchyma. These preliminary results demonstrate the potential utility of BOLD in quantifying tumor hypoxia and evaluating patients prior to and following therapy with TACE.

 

15:00         3742.     Detection of Focal Malignant Liver Lesions: Comparison of T2-Weighted and Diffusion-Weighted Imaging at 1.5T or 3.0T

Computer 68

Hua Wang1, Xiaoying Wang, Xuexiang Jiang

1Tianjin Medical University Cancer Institute and Hospital, Tianjin, People's Republic of China

Thirty-three consecutive patients with focal malignant liver lesions on MR images were included in the study. Among them, nineteen patients were examined at 1.5T and 14 patients at 3.0T. Both T2W and DW imaging were performed on each patient. Two observers interpreted images independently and separately. The signal intensity (SI) of tumors and liver were measured at workstation. The ratio of SI of tumor/liver was calculated on tumors more than 1 cm in diameter and without interference of artifacts. There were no significant differences between the performance of 1.5T and 3T. T2W and DW imaging was similar in detection of focal malignant liver lesions. Combined with T2WI, the detection rate on DWI can be improved.

 

Perfusion of the Liver & Pancreas

Hall D                                   Wednesday 13:30-15:30                                                                                                                                       

13:30         3743.     Geometry and Flow in the Portal Vein of Normal Subjects and Patients Using Magnetic Resonance Imaging

Computer 61

Stephanie M. George1, Puneet Sharma2, Diego R. Martin2, Don P. Giddens1

1Georgia Institute of Technology and Emory University, Atlanta, USA; 2Emory University School of Medicine, Atlanta, USA

Cirrhosis is a leading cause of death in the United States.  Previous studies, using ultrasound, have shown varying differences in portal flow in cirrhosis as compared to normal subjects.  However, the flow was significantly affected by the degree of cirrhosis.  This study evaluates the use of PC-MRI to characterize normal and patient portal hemodynamics as a first step towards non-invasive classification and monitoring of cirrhosis in patients with chronic liver disease.  Image post- processing was performed using MATLAB programs to segment the vessel and acquire the velocity values.  Preliminary results show the feasibility of PC-MRI determination of detailed normal portal vein hemodynamics with future work to include more subjects and subject-specific modeling.

 

14:00         3744.     MR Evaluation of Portal Hypertensive Collateral Shunting Vessels for Prediction of Outcomes After Transjugular Intrahepatic Portosystemic Shunt

Computer 61

Takeshi Yoshikawa1,2, Donald G. Mitchell2, David Eschelman2

1Kobe University Graduate School of Medicine, Kobe, Japan; 2Thomas Jefferson University, Philadelphia, Pennsylvania, USA

TIPS is an interventional radiologic minimal invasive procedures and leads to portal decompression. However, selection of patients is still a controversial issue. In addition, various complications after TIPS, such as shunt dysfunction, onset or worsening of hepatic encephalopathy can worsen patientsf QOL. Also, technical difficulty in TIPS procedure differs from patient to patient. We found that patients with pre-existing large portosystemic shunt showed the trends toward higher initial technical failure and tract stenosis rates, and toward lower onset or worsening rates of hepatic encephalopathy. Our results suggest gadolinium-enhanced MRI has the potential to predict therapeutic effectiveness and complications after TIPS.

 

14:30         3745.     Contrast-Enhanced MR Angiography at 3 Tesla for the Assessment of Vascular Complications of Pancreas Transplantation

Computer 61

Ahmed Mohamed Housseini1,2, Ugur Bozlar1,3, Patrick T. Norton1, Timothy M. Schmitt1, Kenneth L. Brayman1, Hugo Bonatti1, Jaime F. Mata1, Thomas Huerta4, Timothy L. Pruett1, Klaus D. Hagspiel1

1University of Virginia Health System, Charlottesville, USA; 2Suez Canal University, Ismailia, Egypt; 3Gulhane Military Medical Academy, Ankara, Turkey; 4University of Virginia Health System, Charlottesville, Vi

The role of ceMRA at 3Tesla in the assessment of the pancreas allograft vascular system is currently unknown. 10 ceMRA studies in 8 patients with recent transplant dysfunction were analyzed. All exams were diagnostic and signs suggestive of rejection, infarction or major vascular complications were detected in all cases. MRA findings were concurrent with the final clinical diagnosis in all cases. All 22 arterial segments with angiographic correlation showed complete concordance between MRA and DSA. 3T ceMRA of pancreas allografts is accurate in the depiction of the vascular anatomy and can be used to reliably identify clinically relevant vascular complications.

 

15:00         3746.     Role of MR(A) in Assessment of Pancreas Transplant Complications

Computer 61

Taiyo Shimizu1, Lien Tran1, Daniel Margolis1, Steven Raman1, Nagesh Ragavendra1, David Lu1

1David Geffen School of Medicine at UCLA, Los Angeles, California , USA

Pancreas transplant offers life-changing treatment to patients with diabetes mellitus.  Despite the improvements in surgical techniques and medical management, complications are not infrequently encountered.  The role of MR imaging in assessment of these patients have not been clearly established.  Here, we retrospectively reviewed 191 patients who underwent pancreas transplantation.  We found that, while US and CT served as the primary imaging modalities, MR(A) often yielded important information which led to clinical interventions in those that underwent them.  Thus, the present study suggests MR(A) to be a relatively safe and useful mode of study in assessing post-operative complications of pancreas transplantation.

 

Female Pelvis & Fetal Imaging

Hall D                                   Wednesday 13:30-15:30                                                                                                                                       

13:30         3747.     Effect of the Anticholinergic Agent in the Uterus: Size and Signal Change in the Uterine Zonal Anatomy in Fast Spin-Echo T2-Weighted Images [Not Available]

Computer 62

Koji Fujimoto1, Asako Nakai1, Tomohisa Okada1, Takashi Koyama2, Kaori Togashi1

1Graduate School of Medicine, Kyoto University, Kyoto, Japan; 2Kyoto University Hospital, Kyoto, Japan

The purpose of this study was to evaluate the effect of the anticholinergic agent on T2-weighted images of the uterus by comparing images before and after the administration of the drug. The area and signal intensity of the inner, outer layer of the uterine corporeal myometrium and the endometrium were measured and evaluated. In addition to suppression of artifacts by intestinal motion, the anticholinergic agent suppressed uterine myometrial contractility and resulted in significant increase in area and signal intensity of the outer layer of the myometrium. CNR between the inner and outer layer of the myometrium was also increased significantly.

 

14:00         3748.     MRI of Perturbed Decidual Angiogenesis - A Characteristic of an Embryo Implantation Failure Associated with the Conditional Depletion of Uterine Dendritic Cells

Computer 62

Vicki Plaks1, Tal Birnberg1, Tamara Berkutzki1, Vyacheslav Kalchenko1, Gil Mor2, Nava Dekel1, Steffen Jung1, Michal Neeman1

1Weizmann Institute of Science, Rehovot, Israel; 2Yale University School of Medicine, New Haven, USA

The fate of mammalian embryos is frequently decided at implantation, which is a major limiting step in spontaneous and assisted pregnancies. Angiogenesis is a prerequisite for uterine receptivity, as the endometrium transforms into the decidua. MRI was used to evaluate implantation failure caused by depletion of uterine dendritic cells (uDC) in transgenic mice. 3D-MRI using biotin-BSA-GdDTPA revealed that uDC- depleted uteri exhibited impaired decidual angiogenesis characterized by decreased blood volume and increased vascular permeability, opposing the trends of these parameters in normal implantation. Along with other data, this study suggests a novel non-immune role for uDC in tissue remodeling.

 

14:30         3749.     Diffusion-Weighted MRI (DWI) in Ovarian Masses: Value of DWI Compared to T2 and T1-Weighted MRI and Histopathological Findings

Computer 62

Nathalie Hottat1, Thierry Metens1, Martin Kavec1, Celso Matos1

1Erasme Hospital, Brussels, Belgium

The aim of this study is to determine the accuracy of diffusion weighted (DW) imaging in the characterization of ovarian lesions in patients undergoing pelvic MRI. 26 women underwent conventional MR T2-weighted, T1-weighted and DW imaging. All patients underwent surgical excision and MR results were compared to histopathological diagnosis. Combining DW and conventional MR images increased the specificity for the characterization of ovarian masses from 81 to 85%. Colored-ADC map of the lesions and dedicated histogram could be a useful tool in the evaluation of heterogeneous ovarian epithelial tumors.

 

15:00         3750.     Whole Body Post-Mortem Fetal Magnetic Imaging at 9.4T: A Rapid and Less Invasive Autopsy for Small Foetuses

Computer 62

Sudhin Thayyil1, Jon Cleary2, Anthony N. Price2, Rod Jones1, Neil Sebire3, Nikki Robertson4, Mark F. Lythgoe2, Andrew Taylor1

1UCL Institute of Child Health, London, UK; 2UCL Institute of Child Health and Department of Medicine, London, UK; 3Great Ormond Street Hospital NHS Trust, London, UK; 4UCL Institute of Womens Health, London, UK

We describe the first experience of whole body human fetal imaging at 9.4T MRI. 9.4T imaging provided excellent tissue contrast, compared to 1.5T imaging in these fetuses

 

Breast MRI

Hall D                                   Wednesday 13:30-15:30                                                                                                                                       

13:30         3751.     Dynamic Contrast Enhanced MRI of the Breast:  Kinetic Curve Analysis to Determine the Optimal Temporal Resolution

Computer 63

Riham Hossam El-Din El-Khouli1, Michael Jacobs2, Juan Wei2, Peter B. Barker2, Katarzyna J. Macura2, David A. Bluemke2

1Johns Hopkins University, School of Medicine, Baltimore, USA; 2Johns Hopkins University.School of Medicine, Baltimore, USA

Our study aimed to determine the optimal temporal resolution to be used in Dynamuic Contrast EnhancedMRI of the breast. We used a data set of dynamic contrast enhanced MRI with temporal resolution 15 sec per acquisition and then we changed temporal resolution.

 

14:00         3752.     Association of Computer-Based Quantitative Diagnostic Features for CAD with Tumor Phenotype Evaluated by BI-RADS Descriptors

Computer 63

Ke Nie1, Jeon-Hor Chen1, Shadfar Bahri1, Orhan Nalcioglu1, Min-Ying Su1

1University of California, Irvine, Irvine, California , USA

Computer-based quantitative features are needed for development of CAD (computer-aided diagnosis) systems. For these features to be accepted, the link with the well-established BI-RADS descriptors needs to be established. In this study we analyzed the quantitative features selected from a database of 43 malignant and 28 benign lesions. The association of 3 features, Compactness, Gray Level Entropy, and Gray Level Sum Average, with lesion phenotypes was investigated. Shape and margin can both contribute to the compactness index. GLCM entropy is associated with homogeneous/heterogeneous enhancements. The gray level sum average is associated with the degree of enhancements.

 

14:30         3753.     Age- And Race- Dependence of the Percent Fibroglandular Breast Density Evaluated by MRI

Computer 63

Ke Nie1, Ivy Chau2, Siwa Chan2, Tiffany Tseng1, Jeon-Hor Chen1, H-M Baek1, Orhan Nalcioglu1, Min-Ying Su1

1University of California, Irvine, Irvine, California , USA; 2China Medical University Hospital, Taichung 404, Taiwan

A method was developed to measure the percent fibroglandular breast density, and applied to analyze the age- and race-dependence in 168 women. The percent fibroglandular density was 15.5¡À7.0% for women <45 yo; 13.7¡À6.1% for 45-55 yo; and decreased to 8¡À3.7% for women >55 yo (p < 0.0001). For race-dependence, the Asian have the highest density 14.9¡À8.1%, and the lowest 10.1%¡À6% in White (p = 0.05). For women younger than 45, there was no apparent race-dependence. This method may be applied to measure subtle changes in density, for a woman to evaluate her benefits or risks when considering chemoprevention or hormonal replacement therapy.

 

15:00         3754.     Using Two-Dimensional Magnetic Resonance Spectroscopy in Breast Cancer Detection:Comparing 3.0T Versus 1.5T

Computer 63

Xiaoyu Liu1, Scott Lipnick1, Nanette Debruhl1, Roslynn Mcgill1, M A. Thomas1

1UCLA Medical School, Los Angeles, California , USA

Magnetic Resonance Spectroscopy (MRS) allows noninvasive measurements of the concentrations of metabolites in human organs such as breast. Two-dimensional (2D) MRS has better resolution than one-dimensional (1D) MRS by adding a second dimension to each spectrum and has previously been used in breast cancer detection. Recent studies using MRS for human breast cancer detection are limited to 1.5T magnetic fields. The purpose of this study is to compare the spectral resolution and accuracy for breast cancer detection of volume-localized 2D correlated spectroscopy (L-COSY) MRS technique at 1.5T versus 3.0T for detecting breast metabolites.

 

13:30         3755.     Comparison of Choline Concentration and Water-To-Fat Ratio as Biomarkers for Discrimination of Mass/Non-Mass Malignant and Benign Breast Lesions

Computer 64

Sunitha B. Thakur1, Lia Bartella, Nicole Ishill, Laura Liberman, Elizabath A. Morris, David D. Dershaw, Jason A. Koutcher1, Wei Huang1

1Memorial Sloan Kettering Cancer Center, New York, New York, USA

This study was undertaken to compare capabilities of absolute Cho concentration [Cho] and W/F ratio in differentiating mass and non-mass malignant breast lesions from benign lesions. Though both [Cho] and W/F ratio are useful diagnostic biomarkers, this study suggest that [Cho] is significantly better than W/F ratio in differentiating malignant lesions, mass and non-mass, from benign lesions, with higher sensitivity and specificity. There is no significant difference in either [Cho] or W/F ratio between mass and non-mass malignant lesions. Incorporation of [Cho] measurement into clinical breast MRI protocol may reduce the number of possibly unnecessary (benign) biopsies in the future.

 

14:00         3756.     Can We Distinguish Breast Cancer from Mimicking Lesions Using Combined Evaluation with Proton MR Spectroscopy and Dynamic-Contrast -Enhanced MRI? [Not Available]

Computer 64

Motoyuki Katayama1, Takayuki Masui1, Kimihiko Sato1, Hiroki Ikuma1, Hidekazu Seo1, Akihiko Kutsuna1, Haruyuki Fukuchi2, Kenji Asano2

1Seirei Hamamatsu General Hospital, Hamamatsu, Japan; 2GE Yokogawa Medical Systems. Ltd, Hino, Japan

We evaluate breast tumor with combined evaluation of time signal intensity curves from dynamic MRI and existence or absence of a choline peak on 1H-MRS in our routine clinical settings. Although time signal intensity curves with dynamic contrast enhanced MR imaging and existence of a choline peak on 1H-MRS was aids for diagnosis of breast malignancies, there were some cases of overlaps and technical failure.

 

14:30         3757.     Fluctuation of Contralateral Normal Breast Enhancement in DCE-MRI of Breast Cancer Patients Undergoing Chemotherapy

Computer 64

Hon Yu1, Jack Hsu1, Ke Nie1, Muqing Lin1, Siwa Chan2, Jeon-Hor Chen2, Rita S. Mehta1, Orhan Nalcioglu1, Min-Ying Su1

1University of California, Irvine, California , USA; 2China Medical University Hospital, Taichung, Taiwan

The fluctuation of contrast enhancements in the fibroglandular tissue of the contralateral normal breast of 34 patients undergoing neoadjuvant chemotherapy was investigated. Each patient had at least 3 MRIs, and the variation was calculated. To avoid ROI selection bias, a computer-based segmentation method was applied to segment the entire fibroglandular tissue in the normal breast, and a volume-averaged enhancement time course was measured. The results indicated that post-menopausal women had a lower fibroglandular enhancement in the normal breast, also a lower variation over time, possibly indicating less fluctuation coming from the influence of menstrual cycle.

 

15:00         3758.     Changes of Lesion Morphology and Texture During Neoadjuvant Chemotherapy in Breast Cancer

Computer 64

Ke Nie1, Jeon-Hor Chen1, Hon J. Yu1, Shadfar Bahri1, Rita S. Mehta2, Orhan Nalcioglu1, Min-Ying Su1

1University of California, Irvine, Irvine, California , USA; 2Unversity of California, Irvine, California , USA

The change of morphology and texture features of 38 breast cancers receiving AC+taxane neoadjuvant chemotherapy was investigated. Depending on the response to the first line AC and the final pathological finding, the cancers were separated into 4 groups: AC_R (with final CR and PR), and AC_NR (with final CR and PR). Homogeneity index showed a consistent decrease with treatment in the AC_R group, and no significant change in the NR group. The computer extracted information representing lesion morphology and texture changes may have potential to be built into a response prediction model to achieve a high accuracy.

 

13:30         3759.     Assessment of Early Therapeutic Response in Locally Advanced Breast Cancer Using ADC, Volume and Diameter

Computer 65

N R. Jagannathan1, Uma Sharma1, K A. Danishad1, V Seenu1

1All India Institute of Medical Sciences, New Delhi, India

Comparison of changes in apparent diffusion coefficient (ADC), volume and diameter in patients with locally advanced breast cancer after I, II and III NACT revealed statistically significant increase in ADC after I NACT compared to pre-therapy value in clinical responders (R) compared to non-responders (NR). The changes in diameter and volume were evident only after II NACT. This suggests the ability of ADC in differentiating NR from R at an early stage of therapy. The sensitivity to detect responder is high for volume and diameter but specificity was 100%, 50% and 70% for ADC, volume and diameter, respectively.

 

14:00         3760.     Efficacy of Lesion Detection Using Diffusion-Weighted Breast Imaging: Comparison of a STIR DWI (DWIBS) and a Convetional DWI Sequence

Computer 65

Andreas Stadlbauer1, Reinhard Bernt2, Wilma van der Riet3, Stephan Gruber4, Jürgen Haller2, Erich Salomonowitz1

1Landesklinikum St.Poelten, St. Poelten, Austria; 2Hanusch Krankenhaus, Vienna, Austria; 3European MRI Consultancy (EMRIC), Strasbourg, France; 4Medical University Vienna, Vienna, Austria

To evaluate the efficacy of a diffusion-weighted STIR (DWBIS) and a conventional fat-suppressed diffusion-weighted imaging (cDWI) sequence for detection of breast lesions. 33 patients with a suspected breast lesion underwent both sequences. ADC and eADC values of the lesions between all b-value combinations were calculated. Qualitative evaluation of lesion detectability and conspicuity with DWBIS and cDWI was performed. Conspicuity of tumors and fibroadenmas was better for DWIBS compared to cDWI. We found significant differences between tumors and fibroadenomas for ADC[b0,b1], ADC[b0,b2], eADC[b0,b1], eADC[b0,b2] of DWIBS and cDWI. DWIBS is superior to cDWI in visualization of malign and benign lesions.

 

14:30         3761.     Qualitative and Quantitative Diffusion-Weighted Imaging of Breast Lesions at 3T

Computer 65

Gladys Lo1, Victor Ai1, John Chan1, Philip Ng1, Polly Cheung1, KW Li1, Ting Ting Wong1, M Ma1, Raymond Lee1, Daisy Chien2

1Hong Kong Sanatorium, Hong Kong, People's Republic of China; 2UCLA, Los Angeles, California , USA

This is the first clinical study evaluating the value of qualitative versus quantitative diffusion imaging of breast lesions in patients at 3T. Using histologic validations, we determined the sensitivity, specificity, and diagnostic accuracy of qualitative diffusion weighted imaging, quantitative ADC measurement and dynamic contrast-enhanced MRI. We found qualitative diffusion weighted imaging to be highly sensitive in detecting breast lesions while quantitative ADC measurement further increases the specificity to over 90%.

 

15:00         3762.     MRI-Guided Breast Biopsy at 3T Using a Dedicated Large Core Biopsy Set; Feasibility and Initial Results

Computer 65

Ritse M. Mann1, Jeroen Veltman1, Axel Winkel2, Carla Boetes1

1Radboud University Nijmegen Medical Center, Nijmegen, Netherlands; 2INVIVO Germany GMBH, Schwerin, Germany

This study evaluated the use of a dedicated MR-guided breast biopsy set for intervention at 3T. Due to the use of plastic coaxial needles, needle placement can be accurately assessed. The procedure is technically as easy as biopsy at 1.5T and the diagnostic yield is at least equal to biopsy at 1.5T. Therefore, this set allows biopsy of 3T only visible lesions or the performance of biopsy in conjunction with other techniques that benefit from higher field strength.

 

13:30         3763.     Quantitative Morphology and Texture Analysis of Breast Parenchymal Pattern

Computer 66

Ke Nie1, Jeon-Hor Chen1, Siwa Chan2, Orhan Nalcioglu1, Min-Ying Su1

1University of California, Irvine, Irvine, California , USA; 2China Medical University Hospital, Taichung 404, Taiwan

Quantitative texture and morphology analysis was applied to evaluate different breast parenchymal patterns. 43 cases with distinctly different patterns (I: mostly fatty, II: intermingled fat and fibroglandular tissue, III: fibroglandular tissue inside surrounded by fat outside) were identified. The GLCM and LAWS¡¯ texture features could differentiate between Type-I from Type-II and III, but not between Type-II and III. The morphology features of the segmented fibroglandular tissue, particularly the compactness ¡°the ratio of perimeter to area¡± could differentiate between them despite of their similar percent density. The method may be applied to evaluate the association of parenchymal pattern with cancer risk.

 

14:00         3764.     Efficacy of MRI Morphology and Kinetic Parameters in Distinguishing Benign and Malignant Breast Lesion

Computer 66

Tie qiao Du1, bao zhi Ding1, chun yu Sang1, chao zhang1

1Fuxing Hospital Affiliated to Capital University of Medicine Sciences, Beijing, People's Republic of China

Objective: To discuss a effect of combined morphology and kinetic data of MRI in distinguishing malignant tumors from benign lesions of breast. Methods: A CE-MRI study was performed on 17 patients with benign lesion and 16 cases with malignant tumors. Results and conclusion: Marginal feature, shape, spreading signs,time-signal intensity curve, and  signal enhanced rate between the benign and malignant group represented significant difference, respectively. Sensitivity, specificity,and accuracy  combined with  former 5 indicators were 93.8%,88.2%and 90.9%, respectively. The scoring method of breast could help to differentiate malignant from benign lesions.

 

14:30         3765.     Heart Saturation for Bilateral Breast MRI: Reduction of Cardiac Motion Artifacts

Computer 66

Rebecca Rakow-Penner1, Brian Hargraeves1, Laura Pisani1, Bruce Daniel1, Gary H. Glover1

1Stanford University, Stanford, California , USA

Cardiac motion causes significant artifact in breast MRI.  By applying a cylindrical saturation encompassing the heart, heart motion artifact is reduced. The heart saturation pulse is a 2D spiral excitation in both x and y, followed by crushers.  This pulse precedes a spectral spatial bilateral breast acquisition sequence.  The sequence was tested on healthy volunteers and a patient with contrast.  Significant artifact reduction is noted.

 

15:00         3766.     Fat Saturation and Motion Compensation Using Gating and Reordering

Computer 66

Peter Siegler1, Claire Holloway1, Petrina Causer1, Donald Bruce Plewes1

1Sunnybrook Health Sciences Centre, Toronto, Canada

Dynamic contrast enhanced breast MRI is a sensitive technique for the detection of breast cancer. Therefore, to aid breast conserving surgeries, MR breast imaging with supine positioning of the patient was implemented to match the breast configuration in the operating room. Since respiratory motion is not negligible in supine breast MRI, time consuming motion compensation is essential. Conventional fat-suppression would further prolong acquisition, resulting in unacceptably long scan times. Here, a method of partially reordered fat saturation combined with k-space reordering and gating for motion-compensation is presented which allows fast motion-compensated, fat-suppressed, supine breast MRI with minimal increases in scan-time.

 

13:30         3767.     Rapid Acquisition of High Resolution 3D T8-Weighted Water-Silicone Separated Breast Images

Computer 67

Ananth J. Madhuranthakam1, Martin P. Smith2,3, Reed F. Busse4, Huanzhou Yu5, Ann Shimakawa5, Anja C. Brau5, Philip J. Beatty5, Scott B. Reeder6, Neil M. Rofsky2,3, Jean H. Brittain4, Charles A. McKenzie7

1GE Healthcare, Boston, Massachusetts, USA; 2Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; 3Harvard Medical School, Boston, Massachusetts, USA; 4GE Healthcare, Madison, Wisconsin, USA

We demonstrate the rapid acquisition of high-resolution 3D T8-weighted water and silicone separated images of the breast to visualize possible silicone ruptures.  The technique combines the IDEAL (Iterative Decomposition of water and fat with Echo Asymmetry and Least squares estimation) chemical-shift imaging method modified to separate water and silicone with 3D-FSE-Cube that uses an eXtended Echo Train Acquisition (XETA) and 2D partially parallel imaging.  An adiabatic chemically selective inversion pulse is used to suppress the fat.  Uniform separation of water and silicone with high near-isotropic resolution in all three dimensions is achieved in 11.5 minutes of scan time.

 

14:00         3768.     Modified ZMART for Supine Breast MRI

Computer 67

Peter Siegler1, Claire Holloway1, Petrina Causer1, Donald Bruce Plewes1

1Sunnybrook Health Sciences Centre, Toronto, Canada

Dynamic contrast enhanced MRI shows a high sensitivity for breast cancer. Therefore, to allow aid of breast conserving surgeries, MR breast imaging with supine positioning of the patient was  implemented to match the later situation in the operating room. The zonal motion-adapted acquisition and reordering technique (ZMART) was used to compensate for respiratory motion. However, if the respiration pattern during the scan changes, the reordering is modified in order to minimize scan-time, resulting in slightly corrupted reordering results. Here a modified ZMART is proposed, which keeps the reordering scheme constant by allowing a small increase in scan-time.

 

14:30         3769.     Morphologic and Dynamic Differences Between Invasive Ductal and Invasive Lobular Carcinomas of the Breast

Computer 67

Ritse M. Mann1, Henkjan Huisman1, Jeroen Veltman1, Mark Stoutjesdijk1,2, Carla Boetes1

1Radboud University Nijmegen Medical Center, Nijmegen, Netherlands; 2Ikazia Hospital, Rotterdam, Netherlands

This study evaluated differences between invasive lobular carcinomas (ILC)and invasive ductal carcinomas (IDC)of the breast with respect to morphology and enhancement patterns. Apperently, there are no significant differences in morphology, nor in thye most malignant looking voxels, however distribution of kinetic enhancement profiles is significantly different between ILC and IDC.

 

15:00         3770.     Improvement of Fat Suppression in Breast Imaging [Not Available]

Computer 67

Shinichi Kitane1, Mitsue Miyazaki2,3, Erin Kelly1,1, Aida Doubrava,14

1; 2Toshiba Medical Research Institute USA, Vernon Hills, USA; 3Toshiba Medical Systems Corp., Otawara, Japan; 4Rad. LTD, Tucson, Arizona , USA

Breast imaging suffers from B0 and B1 problems due to strong susceptibility effects caused by shapes of breasts and inhomogeneity of coils. Dynamic study using segmented 3D FFE type sequences requires high resolution and good temporal resolution and also demands good fat suppression for diagnostics. Therefore, a short inversion SPIR technique is normally used in dynamic sequences to minimize the inversion time (TI) to reduce the scan time. In this study, we have applied a double fat suppression technique, comprising a spectral-selective SPIR and a CHESS pulses, in 3D dynamic sequence and compared with the regular SPIR 3D dynamic technique.

 

13:30         3771.     Artifact Size Caused by Breast Tissue Marking Clips at 1.5T and 3T MRI: A Phantom Study

Computer 68

Qi Peng1, Carol Dornbluth1, Kenneth A. Kist1, Anqi Zhou1, Pamela M. Otto1

1UT Health Science Center at San Antonio, San Antonio, Texas, USA

3T MRI introduces larger signal void size artifact surrounding metallic breast marking clips than at 1.5T. In this study we compare the signal void artifact size at both 1.5T and 3T and to test the impact of field strength, different readout bandwidth, and TE. At the tested spatial resolution (1×1×2mm3) using a 3D GRE sequence, the artifact sizes at 3T are only 10-20% larger than those of 1.5T. Increasing readout bandwidth didn’t reduce the artifact size, and reducing TE slightly reduced the artifact size. Therefore, 3T scanners can be used to detect and follow-up breast cancer adjacent to metallic tissue marking clips if short TE and high spatial resolution are used.

 

14:00         3772.     Quantitative Measures of Breast Density and Tissue Patterns Using MRI

Computer 68

Catherine Klifa1, Julio Carballido-Gamio2, Jessica Gibbs2, Nola Hylton2

1University of California , San Francisco, California , USA; 2University of California, San Francisco, California , USA

In this study, we investigated quantitative measures of breast tissue patterns using Magnetic Resonance Imaging (MRI). High breast density is a strong marker for breast cancer risk and mammography is currently the approved modality to obtain quantitative breast density assessment. However mammography performs poorly for high-density populations. MRI provides very good soft-tissue contrast and tridimensional information on breast tissue content. We showed that women with similar mammographic breast densities may present very different breast tissue patterns on MRI. We defined new quantitative measures using breast MRI data of 50 normal volunteers and showed that the new MR breast tissue pattern index may provide complementary information to MR breast density. We believe that our new MRI quantitative measures could have applicability to help improve breast cancer risk assessment techniques.

  

14:30         3773.     Segmentation of DCE Breast MRI Masses: Pilot Observer Study

Computer 68

Lina Arbash Meinel1, Thomas Buelow2, Martin Bergtholdt, Ursula Kose3, Akiko Shimauchi4, Gillian Newstead4

1Philips Research of North America, Chicago, Illinois, USA; 2Philips Research Hamburg, Hamburg, Germany; 3Philips Medical Systems, Netherlands; 4University of Chicago, Chicago, Illinois, USA

PURPOSE: A pilot study was performed in preparation for a future clinical study.

METHOD: Two observers traced the borders of 11 masses and placed a seed pixel in three sessions to measure inter-and intra-observer variation. The segmentations were compared pair-wise to evaluate similarity.

RESULTS: The observed inter- and intra-observer variation was similar. The robust seed-point placement was significantly more reproducible than either manual contouring or directly placed seed-points. The percent overlap between computer and manual is not significantly different from the two manual readings.

CONCLUSION: The computerized segmentation with robust seed-point selection is more reproducible and reliable than manual methods.

 

15:00         3774.     The Clinical Value of Three-Dimensional (3D) Dynamic MR Imaging for the Bilateral Breasts: is It Worth Performing for Patients with Microcalcifications on Mammography?

Computer 68

Ayano Akita1, Akihiro Tanimoto1, Shigeo Okuda1, Hiromitsu Jinno2, Michiko Nemoto2, Sachio Kuribayashi1

1Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Japan; 2Keio University School of Medicine, Japan

Three-dimensional dynamic MRI for the bilateral breasts was performed prior to stereotactic vacuum-assisted breast biopsy (SVAB) to evaluate whether the MRI findings can help to predict the presence of malignancy. We devised five categories for MRI findings according to BI-RADS. Assuming that the category 4 and 5 were malignant, mammography had a sensitivity of 50%, a specificity of 86%, and an overall accuracy of 78%, whereas MRI had a sensitivity of 88%, a specificity of 100%, and an overall accuracy of 97%. This method may alter the application of SVAB, with better diagnostic value than mammography alone.

 

Lung MRI

Hall D                                   Thursday 13:30-15:30                                                                                                                                           

13:30         3775.     Dynamic Accelerated 3He MRI of Human Lungs with a 128-Element Receive Coil Array at 3T

Computer 61

Davide Santoro1, Vinay Pai1, Abram Voorhees2, Ray Lee1, Bernd Stoeckel3, Niels Oesingmann3, Jean Reid1, Glyn Johnson1, Daniel Sodickson1

1New York University School of Medicine, New York, USA; 2Siemens Medical Solutions, Inc., Malvern, USA; 3Siemens Medical Solutions, Inc., New York, USA

A set of dynamic 3He images have been acquired with a new 128 channel receiver system and custom-designed 128-element coil array. This technology will ultimately allow high degrees of acceleration that will lead to dramatic improvements in temporal resolution for 3He MRI with possible applications to flow imaging under fast expiration

 

14:00         3776.     Lung Volume and Motion Measured by Dynamic 3D MRI Using a 128-Channel Receiver Coil

Computer 61

Junichi Tokuda1,2, Melanie Schmitt,23, Yanping Sun1,2, Yi Tang1,2, Samuel Patz1,2, Carolyn E. Mountford1,2, Nobuhiko Hata1,2, Lawrence L. Wald,23, Hiroto Hatabu1,2

1Brigham and Women's Hospital, Boston, Massachusetts, USA; 2Harvard Medical School, Boston, Massachusetts, USA; 3Massachusetts General Hospital, Boston, Massachusetts, USA

The feasibility to use a state-of-the-art 3T MRI scanner equipped with a 128-channel coil for the imaging of the free-breathing lung was evaluated. Recent developments in dynamic 3D MRI have enabled physiological study of the lung in a dynamic state, but image quality has limited the accomplishment of automated segmentation. In this study, 3D lung images were acquired from two healthy volunteers every 1.3-1.6 s during free breathing. The images provide sufficient contrast for the observation of chest wall and diaphragm motion as well as the measurement of lung volume and motion based on the automated segmentation.

 

14:30         3777.     Quantitative Analysis of Asynchronous Motions in Human Pulmonary Parenchyma Via Non-Rigid Registration

Computer 61

Masaya Takahashi1, Shigeto Kubo1, Tessa A. Sundaram2, Shigeru Kiryu1, James C. Gee2, Hiroto Hatabu3

1Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; 2University of Pennsylvania, Philadelphia, Pennsylvania, USA; 3Brigham and Women's Hospital, Boston, Massachusetts, USA

The paradoxical motions in thoracoabnominal motions and/or right and left hemidiaphragmatic motions are observed in patients with pulmonary disorders such as emphysema. The quantification of these asynchronous respiratory motions could be a diagnostic method to evaluate the progression of emphysema. In this study, we applied the method to quantify the asynchrony in the right and left parenchymal motion and compared with those in the hemidiaphragmatic motions.

 

15:00         3778.     Influence of Distribution of Emphysema on Diaphragmatic Motion in COPD Patients

Computer 61

Tae Iwasawa1, Hiroshi Takahashi, Takashi Ogura, Toshiyuki Gotoh, Seiichiro Kagei, Junichi Nishimura1, Tomio Inoue

1Kanagawa Cardiovascular & Respiratory Center, Yokohama, Japan

We compared CT and MR of 34 chronic obstructive lung disease (COPD) patients to evaluate the influence of the distribution of the emphysema on the paradoxical diaphragmatic movement (Mp(%)). Average of Mp(%) on MR was 11.9}3.9 (%). It showed significant correlation with forced expiratory volume in 1 second (p=0.04). RA-950 (relative lung volume under -950HU) of lower lung part on CT showed significant correlation with Mp(%) (p<0.001). RA-950 of upper lung fields showed no significant correlation with Mp(%). Our results suggest that emphysema of the lower lung would have greater influence on the diaphragmatic motion than the upper lung emphysema.

 

13:30         3779.     Detection of Reperfused Pulmonary Arteriovenous Malformations with Contrast-Enhanced Magnetic Resonance Angiography

Computer 62

Alexander Massmann1, Armin Opitz1, Marcus Katoh1, Urban W. Geisthoff2, Arno Buecker1, Guenther K. Schneider1

1Saarland University Hospital, Homburg/Saar, Germany; 2Clinics of City Cologne (Holweide), Cologne, Germany

Hereditary hemorrhagic telangiectasia (HHT) also known as Rendu-Osler-Weber disease is an autosomal-dominant inherited vascular disorder associated with mucocutaneous, pulmonary, cerebral and visceral arteriovenous malformations (AVM). Pulmonary arteriovenous shunts (PAVMs) are associated with high morbidity and mortality. The primary choice of treatment of PAVMs is catheter embolization with compact packing of platinum coils, which is technically safe and effective. In contrast to an initial successful occlusion, there may be a reperfusion of embolized feeding vessels or opening of collateral vessels. The study shows that contrast-enhanced magnetic resonance angiography (CE-MRA) is a useful tool for regular follow-up examinations of treated PAVMs.

 

14:00         3780.     Dynamic 3D Contrast-Enhanced Perfusion Imaging of Lung Cancer with One-Second Temporal Resolution

Computer 62

Pippa Storey1, Jane P. Ko1, Daisuke Nonaka1, Harvey Pass1, Andrew D. Hardie1, Daniel Moses1, Kellyanne Mcgorty1, Jean Reid1, Jeff L. Zhang1, Ke Zhang1, Qun Chen1

1New York University School of Medicine, New York, New York, USA

Quantitative perfusion imaging of lung cancer has to date been precluded by the low temporal resolution of conventional dynamic contrast-enhanced techniques. By combining a variety of fast imaging methods, such as parallel imaging, partial Fourier sampling and TWIST, we have achieved one-second temporal resolution with 3D coverage of the tumor and high spatial resolution. This allows images to be acquired continuously during free breathing with minimal motion artifacts throughout the baseline, uptake and washout phases of the contrast agent. Application of tracer kinetic models may provide useful information regarding measures of angiogenesis such as tumor vascularity and vessel permeability.

 

14:30         3781.     3D Quantitative Contrast-Enhanced Perfusion Measurements of the Human Lung Using the Prebolus Approach and Signal Corrections
[Not Available]

Computer 62

Markus Oechsner1,2, Christian Oliver Ritter1, Marc Hagemeister1, Peter M. Jakob1, Tobias Wichmann1, Dietbert Hahn1, Meinrad Beer1, Herbert Köstler1

1University of Wuerzburg, Wuerzburg, Germany

Whole lung contrast-enhanced quantification of pulmonary perfusion was performed with different doses using the prebolus approach and with single bolus. The signal curves from all slices were corrected for the sensitivity profile of the array-coil. Corrected perfusion values increased from ventral to dorsal. Without signal correction, higher PBF was found in ventral and dorsal slices. The application of high doses resulted signal saturation in lung parenchyma as well as in the AIF. With the prebolus technique, higher doses can be used to improve the SNR in lung parenchyma.

 

15:00         3782.     Lung Cancer Perfusion: Hybrid Acquisition Technique for 3D MRI to Overcome Breath Hold Limitations and Minimize Motion-Related Displacement

Computer 62

Christian Hintze1, Alto Stemmer2, Michael Bock1, Tristan Kuder1, Frank Risse1, Julien Dinkel1, Michael Puderbach1, Christian Fink3, Hans Ulrich Kauczor1, Jürgen Biederer1,4

1German Cancer Research Center, Heidelberg, Germany; 2Siemens AG, Erlangen, Germany; 3University Hospital Mannheim, Mannheim, Germany; 4University Hospital Schleswig-Holstein Campus Kiel , Kiel, Germany

To record perfusion of lung cancer by imaging requires examination times exceeding breath hold capabilities of patients. The assessment is further disturbed by overall motion of the thorax. The aim of this MR study was to evaluate a hybrid breath hold and navigator triggered technique in combination with a FLASH 3D in imaging lung tumor perfusion to overcome the motion-related challenges. Contrast-enhanced dynamic 3D MRI perfusion studies with initial high temporal resolution of wash-in and subsequent expiratory triggered coverage of wash-out for a typical combined acquisition time of 4 minutes were successfully performed in lung cancer examinations.

 

13:30         3783.     Oxygen-Enhanced T1- And T2*-Mapping of the Human Lung at 0.2 Tesla [Not Available]

Computer 63

Markus Oechsner1,2, Daniel Stäb1, Eberhard Daniel Pracht1, Johannes F.T. Arnold1, Herbert Köstler1, Dietbert Hahn1, Meinrad Beer1, Peter M. Jakob1

1University of Wuerzburg, Wuerzburg, Germany

The object of this work was the implementation and measurement of oxygen-enhanced T1 and T2* maps for functional lung imaging at 0.2 Tesla. T1 maps were acquired with an IR-Snapshot FLASH sequence. T2* was measured with a multi gradient-echo sequence. Furthermore,  a navigator-echo technique was used, to acquire T2* maps during free respiration. A distinct reduction of both relaxation times (T1 ~ 8%; T2* ~ 9%) was found when changing the respiratory gas to 100% oxygen. All measurements were successfully performed during breath-hold or free respiration and are thus applicable for examinations of lung patients.

  

14:00         3784.     Influence to Oxygen-Enhanced MR Imaging: Comparison Between Non-Slice and Slice Selective Types on HASTE Sequence with Adiabatic Inversion Pulse

Computer 63

Daisuke Takenaka1, Michael Puderbach2, Yoshiharu Ohno1, Michael Bock2, Frank Risse2, Sebastian Ley2, Hans Ulrich Kauczor, Kazuro Sugimura1

1Kobe University Graduate School of Medicine, Kobe, Japan; 2German Cancer Research Center, Germany

Oxygen-enhanced MR imaging has been reported as one of the pulmonary functional MR imaging, and potential for assessment of ventilation and/ or oxygen-transfer.  In the past literature, a few investigators suggested that slice selection type might have influence to oxygen-enhancement within the lung.   However no one has clearly described the influence of IR pulse type between slice-selective and non-slice-selective on oxygen-enhanced MR imaging of lung. The purpose of the present study is to demonstrate the influence of slice selection type of oxygen-enhanced MR imaging to oxygen-enhancement within the lung.

 

14:30         3785.     Quantitative MRI Measurement of Lung Density Must Account for the Change in T2* with Lung Inflation

Computer 63

Rebecca J. Theilmann1, Tatsuya J. Arai1, Ahsan Samiee1, Susan R. Hopkins1, Richard B. Buxton1, David J. Dubowitz1, Gordon K. Prisk1

1UCSD, La Jolla, California , USA

Because of high magnetic susceptibility effects in the lung, T2* is extremely short and as a result standard GRE imaging of the lung suffers from significant signal loss. For an accurate determination of lung water content one must back-extrapolate the signal from lung to an echo time of 0. To obtain T2* and lung density measurements, a GRE sequence was developed that rapidly acquires multiple single echo acquisitions within a single breath-hold. Results show that T2* increases with decreasing lung volume and increasing lung density.

 

15:00         3786.     Correction of Errors Due to RF Field Inhomogeneities in Hyperpolarized 3He Measurement of Alveolar Oxygen Partial Pressure in Human  Lung

Computer 63

Alexei V. Ouriadov1, Roya Etemad-Rezai2, Grace Parraga1, Giles Santyr1,3

1Robarts Research Institute, London, Canada; 2London Health Science Centre, London, Canada; 3University of Western Ontario, London, Canada

Helium MR imaging was used to obtain alveolar oxygen partial pressure map of five healthy volunteers and B1 filed map. Measurements were performed at 3T (GEHC, Excite12.0). It was shown that inhomogeneous RF coils leads to variations in flip angle across the lung which can propagate into pA02 inaccuracy. Results of B1 field corrections for the five human subjects suggest that once found, the B1 field map for the RF coil in the magnet can be used to correct pAO2 maps from any subject in any position, provided that the coil is re-positioned identically in the magnet for each subject.

 

13:30         3787.     Assessing Local Lung Function: Measurement of Regional FEV1/FVC Using Tissue Tracking MRI

Computer 64

Ke Zhang1, Abram Voorhees2, Elan Grossman1, Kenneth I. Berger1, Roberta M. Goldring1, Joan Reibman1, Chun Xu3, Larry Dougherty3, Qun Chen1

1New York University, New York, New York, USA; 2Siemens Medical USA, Malvern, Pennsylvania, USA; 3University of Pennsylvania, Philadelphia, Pennsylvania, USA

We have shown the capability of using a real time tissue tracking MRI technique for the quantitative measurement of regional mechanics of the lung. Particularly, we have demonstrated that local FEV1/FVC can be measured on a regional basis, showing marked difference in local lung function between healthy subjects and patients with asthma. Such an assessment of airflow dynamics at the local level may provide a potentially very powerful tool for evaluating the contribution of peripheral airways to obstructive airway disease.

 

14:00         3788.     Fluorine-19 MRI of the Lung During High Frequency Oscillatory Ventilation (HFOV): Visualization of the Wash-Out of C4F8

Computer 64

Ursula Wolf1, Alexander Scholz1, Matthias David1, Rainer Koebrich2, Maxim Terekhov1, Wolfgang Guenter Schreiber1

1Johannes Gutenberg University, Mainz, Germany; 2Maquet, Germany

In clinical research, diagnostic imaging is the main application field of MRI. With the advent of MRI of contrast gases, not only gas filled spaces within the body can be visualized, but also flow mechanics of these gases within the bronchial tree. During high frequency oscillatory ventilation (HFOV), very small tidal volumes are applied at high frequencies. As HFOV is considered as lung protective, it is used in ARDS patients. To contribute to a better understanding of HFOV, we visualized the wash-out of C4F8 gas during HFOV at two different frequencies in healthy pigs.

 

14:30         3789.     In-Vivo Hyperpolarized 3He Lung Imaging in Mice Using X-Centric FGRE Sequence and Custom-Designed FlexiVent Ventilator

Computer 64

Alexei V. Ouriadov1, Richard Kennan2, Deborah Slipetz3, Giles Santyr1,4, Donald Williams3, Brian K. Rutt1,4, Richard Hargreaves3, Ben T. Chen2,3

1Robarts Research Institute, London, Canada; 2Merck Co., Rahway, New Jersey, USA; 3Merck Frosst Ltd., Kirkland, Canada; 4University of Western Ontario, London, Canada

Due to the size of the mouse, the requirements for high image resolution and animal preparations to establish a stable physiological condition and HP 3He gas delivery are very challenging to meet. FGRE sequence has not been widely used for high resolution HP 3He lung imaging in mice as the frequency encoding gradient could cause 3He signal loss in the larger airways due to diffusion. We successfully acquired high-resolution HP 3He lung images in mice using the modified x-centric fGRE sequence to minimize diffusion attenuation. The custom-built flexiVent ventilator provides critical lung function data for image analysis and interpretation.

 

15:00         3790.     An MR-Compatible Active Breathing Control (MR-ABC)

Computer 64

Johannes FT Arnold1,2, Philipp Mörchel1, Eckard Glaser3, Peter M. Jakob1

1University of Würzburg, Würzburg, Germany; 2Research Center for Magnetic Resonance Bavaria (MRB), Würzburg, Germany; 3Viasys Healthcare, Höchberg, Germany

Motion is a major obstacle for cardiac, chest, and abdominal imaging. Several approaches have been proposed to allow for segmented k-space acquisition while avoiding motion artifacts. Most of these methods focus solely on the detection of motion, e.g. navigator techniques or a respiratory belt. Nevertheless, respiratory movement during data acquisition is not prevented with these techniques. To avoid respiratory movement during the data sampling period, an MR-compatible active breathing control (MR-ABC) was developed. The MR-ABC allows for cardiorespiratoy-synchronized MRI while “freezing” the breathing motion. The potential of an MR-ABC device is demonstrated in lung imaging.

 

Metabolism - Clinical Studies

Hall D                                   Thursday 13:30-15:30                                                                                                                                           

13:30         3791.     Validation of Fully Automated Segmentation of Visceral Adipose Tissue from Whole-Body Continuously Moving Bed MRI

Computer 65

Joel Kullberg1, Lars Johansson1,2, Håkan Ahlström1, Frederic Courivaud3, Peter Koken4, Holger Eggers4, Peter Börnert4

1Uppsala University, Uppsala, Sweden; 2AstraZeneca R&D, Mölndal, Sweden; 3Philips Medical Systems, Oslo, Norway; 4Philips Research Europe, Hamburg, Germany

A fully automated technique for segmentation of visceral adipose tissue from whole-body reconstructed fat and water image data is presented. Data is acquired using continuously moving table imaging. The segmentation technique is based on commonly used image processing methods. The validation was performed using ten volunteers and manually segmented results were used as reference. The segmentation results are promising. Results can likely be improved further by automated exclusion of bone marrow.

 

14:00         3792.     Reproducibility of Fast Whole-Body Assessment of Adipose Tissue Depots from Continuously Moving Bed MRI

Computer 65

Joel Kullberg1, Lars Johansson1,2, Håkan Ahlström1, Frederic Courivaud3, Peter Koken4, Holger Eggers4, Peter Börnert4

1Uppsala University, Uppsala, Sweden; 2AstraZeneca R&D, Mölndal, Sweden; 3Philips Medical Systems, Oslo, Norway; 4Philips Research Europe, Hamburg, Germany

Method reproducibility studies give information about method precision and variability, which is essential for study group size determinations. Continuously moving bed imaging can be used to rapidly acquire whole-body MRI data allowing assessment of adipose tissue distribution. A recently developed image processing algorithm can be used to extract and separate abdominal visceral and subcutaneous adipose tissue from these whole-body datasets. The reproducibility of this acquisition and post processing has been studied using repeated acquisitions of nine volunteer subjects. Results suggest a substantial value in this type of acquisition and analysis technique allowing obesity related studies of large patient cohorts.

 

14:30         3793.     Lipid Fraction Measurement Incorporating T1 and RF Inhomogeneity Correction

Computer 65

Jinghua Wang1, Hyeonjin Kim2, Maolin Qiu2, Robert Todd Constable2

1Yale University , New Haven, Connecticut, USA; 2Yale University, New Haven, Connecticut, USA

The content and distribution of fat in humans has received increased attention in recent years because of its relationship to many diseases including cancer, coronary heart disease, diabetes, and obesity. Quantification of lipid, therefore, is very significant for diagnoses, treatment, and understanding disease processes [1, 2].  At short TR, lipid content measured strongly depends on relaxation times, RF inhomogeneity, and pulse sequences [3, 4].  Here, the lipid fraction in skeletal muscle is accurately estimated by incorporating T1 and RF inhomogeneity corrections.

 

15:00         3794.     Absolute Quantification of Adipose Tissue Fat Mass by MRI Using a Signal Intensity Based Model

Computer 65

Houchun Harry Hu1, Krishna S. Nayak1

1University of Southern California, Los Angeles, California , USA

A quantification scheme is presented to compute adipose tissue fat mass on a voxel-by-voxel basis using MRI.  The method utilizes chemical-shift techniques to separate fat and water components.  In this work, we demonstrate the quantification using low-flip-angle spoiled-gradient-echo data, such that resultant image signal intensity is approximately a linear function of proton density.  Fat mass in several ex vivo swine samples are calculated, where values from MRI are within 5-8% of results obtained from reference lipid chemical assay.  We hypothesize that the method potentially represents a non-invasive and accurate approach to measure fat mass in body composition and obesity research.

 

13:30         3795.     Quantification of Pancreatic and Hepatic Fat Using Gradient Echo MRI – Comparison of a Spatial-Spectral Excitation Technique with In/Opposed-Phase Imaging

Computer 66

Nina Franziska Schwenzer1,2, Jürgen Machann1, Petros Martirosian1, Christina Schraml1, Claus D. Claussen1, Fritz Schick1

1University Hospital of Tuebingen, Tuebingen, Germany

Fatty infiltration of pancreas and liver occurs in several metabolic disorders. The most common MRI technique to quantify fat uses in-phase and opposed-phase (IN/OP) images. Unfortunately, this technique is hampered by relaxation effects (T1/T2*).

Therefore, goal of the present study was the quantification of pancreatic and hepatic fat using fat-selective spectral-spatial gradient-echo imaging and the comparison of the gained results with an IN/OP method.

The results suggest that both methods are valid for pancreatic and hepatic fat quantification. However, spectral-spatial imaging seems to be a more promising approach in clinical routine offering solid values without major T1/T2* corrections.

 

 14:00         3796.     Improved Detection of Pancreatic Islets in Vivo Using Double Contrast

Computer 66

Vít Herynek1, Zuzana Berková1, Peter Girman1, Frantisek Saudek1, Milan Hájek1

1Institute for Clinical and Experimental Medicine, Prague, Czech Republic

Transplantation of pancreatic islets is an alternative approach to the treatment of type 1 diabetes. Visualization of transplanted islets using MRI requires labeling of islets by a suitable contrast agent. Detection of islets labeled by iron oxide based contrast agents can be significantly improved using intravenous administration of a suitable gadolinium contrast agent prior to MRI.

 

14:30         3797.     Following of the Fate of Transplanted Pancreatic Islets in the Early Post-Transplant Period by MRI. Their Automatic Detection and Quantification

Computer 66

Daniel Jirak1, Jan Kriz1, Michal Strzelecki2, David White1, Paula Foster1

1Robarts Research Institute, London, Canada; 2Technical University of Lodz, Lodz, Poland

We present a novel transplantation model and a simple and robust segmentation method, which allow an easy quantification of iron-labeled cells and minimizes subjective evaluation. Our approach was applied to the task of monitoring the fate of transplanted pancreatic islets in diabetic mice during the early post transplant period. MRI analysis shows erratic response to transplanted tissue in the first few days. The effect of acute rejection in the second week caused differences between isograft and allograft Tx to be observed.

 

15:00         3798.     Regional Quantitative DCE-MRI in the Pancreas

Computer 66

Josephine Helen Naish1, Charles E. Hutchinson1, Zahra Esmail2, Yvon Watson1, Sue Cheung1, Deirdre M. McGrath1, John C. Waterton1,3, Paul D. Hockings4, Chris J. Taylor1, Geoff J. Parker1

1University of Manchester, Manchester, UK; 2University of Salford, Salford, UK; 3AstraZeneca, Macclesfield, UK; 4AstraZeneca, Mölndal, Sweden

Functional MRI methods may provide valuable probes of pancreatic islet microvasculature, important in the study and treatment of diabetes mellitus. In this study we demonstrate the feasibility of regional tracer kinetic model based DCE-MRI in healthy volunteers. Sensitivity of the technique is investigated by comparing regions of interest in the head and tail sections of the pancreas. Parameters relating to the blood volume and capillary permeability differ significantly between the head and tail, possibility reflecting structural differences between these regions.

 

Prostate Cancer

Hall D                                   Monday 14:00-16:00                                                                                                                                             

14:00         3799.     Prostate Cancer Detection in Patients with Intermediate Prostate Specific Antigen Level Using Combined Trace Apparent Diffusion Coefficient and Nodular Size: Comparison with Transrectal Core Biopsy

Computer 69

Yu-Jen Chen1, Yuan-Shiaw Pu, Chia-Ton Shun, Wei-Cyne Chu2, Wen-Yi Isaac Tseng,3

1Institute of Biomedical Engineering, National Yang-Ming University, Taipei, Taiwan; 2Institution of Biomedical Engineering, National Yang-Ming University, Taipei, Taiwan; 3Center for Optoelectronic Biomedicine, National T

This is a prospective study using diffusion tensor imaging for detecting prostate cancer in the intermediate risk patients, who have the PSA level of 4~20ng/ml. Comparing with TRUS-biopsy results, the judgments only using tADC showed a high NPV of 99%. It indicates the method can effectively exclude the unnecessary biopsies from this patient group. Combining the criterion of nodular size, the comparison with pathologies showed high corresponding results with accuracy of 97%. This validates the method using combined tADC and nodular size can be an effectual tool in pre-biopsy screening.

 

14:30         3800.     High Resolution Diffusion Tensor Imaging in Prostate Cancer

Computer 69

Yu-Jen Chen1, Woei-Cyne Chu2, Wen-Yi Isaac Tseng,3

1Institute of Biomedical Engineering, National Yang-Ming University, Taipei, Taiwan; 2Institution of Biomedical Engineering, National Yang-Ming University, Taipei, Taiwan; 3Center for Optoelectronic Biomedicine, National T

In this study, we used endorectal coils to acquire high resolution, high signal-to-noise (SNR) DTI images on patients who had biopsy proven prostate cancer. The aim of the study was to examine the correlations between tADC and FA values amongst benign and tumor tissues and to assess the feasibility of using high resolution DTI technique in identifying prostate cancer. Our results showed both tADC and FA values were significantly different between tumor and benign tissues. In addition, tADC and FA values exhibit a high negative correlation in cancerous tissues.

 

15:00         3801.     Apparent Diffusion Coefficient as a Prognostic Biomarker in Early Stage Prostate Cancer

Computer 69

Nandita M. deSouza1, Veronica A. Morgan, Sophie F. Riches2, Chris Parker1, Nicholas J. vanAs1

1Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, UK; 2Institute of Cancer Research, Sutton, UK

The challenge of managing localised prostate cancer is to distinguish patients who benefit from radical treatment from those who do not. This study investigates apparent diffusion coefficient (ADC) obtained on diffusion-weighted imaging as a prognostic biomarker in prostate cancer patients managed by active surveillance. On univariate analysis tumor ADC was a significant predictor of adverse repeat biopsy findings (p<0.0001) and time to radical treatment (p<0.0001). Area under ROC curves for ADC was 0.70 for adverse repeat biopsy findings; 0.83 for prediction of radical treatment. ADC is potentially useful for identifying patients with localized prostate cancer at risk of disease progression.

 

15:30         3802.     Monitoring Prostate Cancer Progression with Diffusion Weighted Imaging: Variability of Apparent Diffusion Coefficient Measurements with ROI Placement Technique and Time

Computer 69

Veronica Anna Morgan1, Sophie F. Riches2, Nicholas Van As3, Nandita M. deSouza2

1Royal Mardsen Hospital NHS Trust, Sutton, UK; 2Institute of Cancer Research, Sutton, UK; 3Royal Marsden NHS Trust, Sutton, UK

This study investigates use of diffusion-weighted MRI for monitoring prostate cancer progression in patients on active surveillance. Initially, variability in apparent diffusion coefficient (ADC) over whole prostate with time and in tumor with ROI placement techniques was investigated. 19 patients studied at baseline and 2-years showed significant reduction (p=0.03) in fast component of ADC, suggesting reduction in perfusion over this time. Tumor ADCs were significantly lower (p=0.001) using ADC-derived compared with T2-derived ROIs. There was no significant difference in ADC in patients that progressed to radical treatment compared to those that did not indicating that ADC may not reliably be used to monitor disease progression.

 

 14:00         3803.     Quantification of Metabolites in HR-MAS Spectra of Human Prostate Biopsy Tissues Using ERETIC and the QUEST Algorithm

Computer 70

Vickie Yi Zhang1, Helena Gurascier1, Mark Albers1,2, Helene Ratiney3, Laura Tabatabai, Jeff Simko, Ying Lu1, Daniel Vigneron1, Mark Swanson1, John Kurhanewicz1,2

1University of California, San Francisco, San Francisco, California , USA; 2UC Berkeley / UC San Francisco, San Francisco, California , USA; 3 Université de Lyon, Villeurbanne, France

> An automated time domain based fitting algorithm (QUEST) was used with the Electronic Reference To access In vivo Concentrations (ERETIC) quantification standard to determine the absolute concentrations of 19 metabolites in 106 1H high resolution magic angle spinning (HR-MAS) spectra of human prostate biopsy tissues.   The combination of QUEST and ERETIC provided robust metabolite quantification with minimal user input and potential for human bias. Nine metabolites (PC, GPC, choline, PE, lactate, alanine, citrate, polyamines, glutamine and glutamate) were found to be significantly different between healthy glandular, stromal, and prostate cancer tissues.

 

14:30         3804.     Comparison of 2D JPRESS and 2D L-COSY on Detecting Polyamines and Citrate Metabolites for Prostate Study

Computer 70

Hui Liu1, Ming-Ying Su, Mark Hamamura2, Hyeon Man Baek, Seung-Hong Ha, Tugan Muftler, Orhan Nalcioglu

1University of California,Irvine, Irvine, California , USA; 2University of California, Irvine, USA

Polyamines are new promising biomarkers for prostate cancer study. It was claimed by other researchers that combining polyamine levels and traditional (Choline+Creatine)/Citrate ratio will improve the specifity and sensivity. Traditional 1D MRS and 2D JPRESS suffered from over-crowded and complex spectrum because of limited spectral resolution and strong coupling effects. 2D L-COSY method has better spectral dispersion of J cross-peaks and

is able to detect short TE metabolites compared to 2D JPRESS. Thus, Combined 2D L-COSY and MRSI is a new promising strategy for better detection and monitoring prostate cancer if using polyamine as target biomarker.

 

15:00         3805.     The Clinical Value of MR Elastography in Diagnosis of Prostate Cancer at 3.0T [Not Available]

Computer 70

Saying Li1, Min Chen1, Xuna Zhao2, Shuguang Hu2, Cheng Zhou1

1Beijing Hospital, Beijing, People's Republic of China; 2Philips Medical System, Beijing, People's Republic of China

MR elastography is a new imaging tool capable of assessing the viscoelastic properties of tissue. The purpose of our study was to investigate the clinical value of MRE in diagnosis of prostate cancer at 3.0T, and to assess the viscoelastic properties of prostate cancer and prostatitis. Eight patients with prostate cancer and 10 patients with prostatitis were evaluated by MRE. We found the viscosity and elasticity were significantly higher in the lesions with prostate cancer than with prostatitis. In conclusion, MRE can visualize the different viscoelasticity between prostate cancer and prostatitis, and has great potential in diagnosis of prostate cancer.

  

15:30         3806.     Integration of MRS and DWI in the Diagnosis of Prostate Cancer

Computer 70

Dong Jiao Lu1,2, Xue Mei Guo,12, Fei Yu Li,12, Jue Zhang1, Xiao Ying Wang,12, Jing Fang1

1Peking University, Beijing, People's Republic of China; 2Peking University First Hospital, Beijing, People's Republic of China

Magnetic Resonance Spectroscopy (MRS) and Diffusion Weighted Imaging (DWI) play different roles in the detection of prostate cancer (Pca). Their importance in diagnosis may be reflected by their weights. In this study, we make an effort to investigate the performances of MRS and DWI in the detection of Pca by Fisher linear discriminant analysis.

 

14:00         3807.     Characterization of Prostate Cancer with Perfusion MR Imaging

Computer 71

Louisa Bokacheva1, Kiran Sheikh1, Henry Rusinek1, Artem Mikheev1, Danny Kim1, Xiangtian Kong1, Jonathan Melamed1, Bachir Taouli1

1New York University School of Medicine, New York, USA

Thirty patients with confirmed prostate cancer were assessed with conventional static T2-weighted imaging and perfusion MRI. Ten patients underwent radical prostatectomy, and excised prostates were evaluated by histological analysis. Maps of blood-tissue transfer constant Ktrans and volume fraction of extracellular extravascular space (EES) were created using Tofts model. For ROIs placed in muscle, normal peripheral zone, normal central gland, and tumor, highly significant differences were found in values of Ktrans and EES fraction. Discrimination of tumor from normal tissue resulted in areas under the ROC curves of 0.88 for Ktrans and 0.78 for EES volume fraction.

 

14:30         3808.     High Spatio-Temporal Resolution Dynamic Contrast Enhanced MRI of the Prostate

Computer 71

Akira Kawashima1, Manojkumar Saranathan2, Sandeep Gupta3, Dan Rettmann2

1Mayo Clinic, Rochester, Minnesota, USA; 2Global Applied Science Lab, GE Healthcare, Rochester, Minnesota, USA; 3Global Research Center, GE Healthcare, Niskayuna, New York, USA

Dynamic gadolinium contrast enhanced MR imaging (DCEMRI) of the prostate has been shown to improve the detection, localization and tumor staging of prostate carcinoma and to supplement the limitations of morphologic T2-weighted imaging. Recently, fat suppressed 3D SPGR sequences have been utilized for DCEMRI of the prostate with the usual trade-off between spatial and temporal resolution. There has been a renewed interest in pharmacokinetic modeling of tumors, specifically in generating quantitative parametric maps (Ktrans and Vep), due to their role in assessment of response to medical therapy. However, the generation of reliable parametric maps demands a high spatio-temporal resolution acquisition methodology, seldom achieved or at the cost of spatial coverage. In this study, we investigated the use of a highly accelerated fat saturated elliptic centric TRICKS acquisition for dynamic high spatial and temporal resolution imaging of the prostate and its potential utility in pharmacokinetic modeling on a 3T system.

 

15:00         3809.     3 Tesla High Spatial Resolution Dynamic Contrast Enhanced and T2-W Prostate Magnetic Resonance Imaging (MRI): Detection of Extracapsular Extension and Staging of Prostate Cancer in Routine Clinical Practice

Computer 71

Boris Nicolas Bloch1, Tania Velez1, Robert E. Lenkinski1, Herbert Y. Kressel1, Daniel DaCosta1, Martin P. Smith1, Ivan Pedrosa1, Mary G. Hochman1, Long Ngo1, Elizabeth Genega1, Neil M. Rofsky1

1Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA

We evaluated the sensitivity and specificity of high spatial resolution dynamic contrast enhanced (DCE) MRI combined with T2-W endorectal coil MRI at 3 Tesla for assessment of extracapsular extension and staging of prostate cancer in a routine clinical setting, using histopathology as the reference standard. The sensitivity, specificity, PPV and NPV for ECE for all readers was 76%, 90%, 78% and 89%, respectively; for the most experienced reader 83%, 93%, 83% and 93%, respectively. The staging accuracy (AUC) for all readers was 87% (range: 78-93%). This study demonstrates the utility of combined high spatial resolution DCE and T2-W MRI at 3T, yielding improved assessment of ECE and high staging accuracy of prostate cancer in routine clinical practice.

 

 15:30         3810.     simultaneous Diffusion and Perfusion Imaging Provides Complementary Functional Data That Can Be Used in the Pre- And Post Therapeutic Disease Management in Prostate Cancer Patients

Computer 71

Greetje Groenendaal1, Cornelis A.T. van den Berg1, Ellen M.A. Roeloffzen1, Jan G. Korporaal1, Peter R. Luijten1, Marco van Vulpen1, Uulke A. van der Heide1

1University Medical Center Utrecht, Utrecht, Netherlands

Dynamic contrast-enhanced (DCE) and diffusion-weighted imaging (DWI) have both shown to be able to discriminate benign from malignant regions in the prostate. As contrast generated by these techniques stems from different physiology, we have studied the correlation between changes in perfusion and diffusion of suspicious regions found with both imaging techniques. We found that simultaneous diffusion and perfusion imaging provides complementary functional data that can be used in the pre- and post therapeutic disease management in prostate cancer patients.

 

Advances in Tumor MRS

Hall D                                   Monday 14:00-16:00                                                                                                                                             

14:00         3811.     Histone Deacetylase Inhibition by MRS: Comparison of in Vitro and in vivo Studies

Computer 72

Madhuri Sankaranarayanapillai1, James A. Bankson1, Qing Yuan1, Hagit Dafni2, Douglas D. Webb1, Ashutosh Pal1, Edward F. Jackson1, Juri G. Gelovani1, William P. Tong1, Sabrina M. Ronen2

1U.T. M.D. Anderson Cancer Center, Houston, USA; 2University of California at San Francisco, San Francisco, USA

Histone deacetylase (HDAC) inhibitors (HDACI) are emerging as promising antineoplastic agents. We previously showed that intracellular levels of 19F MRS-detectable Boc-Lys-TFA-OH (BLT) are correlated with HDAC activity and that this method can be used in both cells and tumors to monitor HDAC inhibition. Here we show that in contrast to our in vitro observations, phosphomonoester  levels determined by 31P MRS did not change in PC3 tumor xenografts following SAHA treatment. Our results suggest that 19F MRS of BLT is a potential noninvasive method of monitoring HDAC activity in vivo whereas PC is not a reliable marker of HDAC inhibition.

 

14:30         3812.     Improving in Vivo Brain Tumor Phenotyping with MRS Pattern Perturbation and Pattern Recognition Analysis

Computer 72

Rui Vasco Simões1,2, Margarida Julià-Sapé1,3, Sebastián Cerdán4, Carles Arús1,3

1Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain; 2Universidade de Coimbra, Coimbra, Portugal; 3Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Cerdanyol

MRS pattern recognition analysis is becoming an invaluable tool for the non-invasive classification of human brain tumors but still fails to fully discriminate between certain types and grades. Based on the reproducible effects of hyperglycemia in a mouse model of brain glioma, as monitored by 1H MRS, we have recently suggested MRS pattern perturbation as a potential tool for increasing the dynamic range for brain tumor classification in vivo. Here we show preliminary results that point towards pattern recognition analysis as a fast and accurate method for discriminating MRS patterns upon such metabolic challenge.

 

15:00         3813.     Choline Production and Her-2/neu Expression in Breast Cancer Measured by MRI/MRSI [Not Available]

Computer 72

Wenlian Zhu1, Baasil Okollie1, Zaver Bhujwalla1, Dmitri Artemov1

1Johns Hopkins University, Baltimore, Maryland, USA

The ability to image the Her2neu receptor with MRI allows us to investigate ‘molecular-functional’ relationships between receptor expression and metabolism.  We typically observe a heterogenous distribution of the Her2neu receptor in tumors.  Since we previously observed increased phosphocholine in breast epithelial cells transfected with the erbB2 (Her2neu) oncogene, here we have examined the relationship between Her2neu expression and the distribution of total choline.

 

15:30         3814.     Choline Kinase Over Expression Increases Drug Resistance and Invasion in MCF7 Breast Cancer Cells

Computer 72

Tariq Shah1, Flonne Wildes1, Marie-France Penet1, Paul T. Winnard Jr.1, Kristine Glunde1, Dmitri Artemov1, Venu Raman1, Ellen Ackerstaff1, Zaver M. Bhujwalla1

1Johns Hopkins School of Medicine, Baltimore, USA

Increased expression of choline kinase (Chk) is one of the major factors contributing to the elevated phosphocholine and total choline signals observed in MRS studies of tumors.  We previously observed that si-RNA-mediated down-regulation of Chk in breast cancer induced differentiation and increased the effect of treatment with 5-fluorouracil (5-FU).  Here we have shown that overexpression of Chk in poorly invasive MCF-7 breast cancer cells increased phosphocholine and resulted in a significant increase of resistance to 5-FU as well as exclusion of rhodamine-123.  A small but significant increase in invasion was also observed although cell proliferation rates were not significantly altered.

 

Advances in Tumor MRI

Hall D                                   Tuesday 13:30-15:30                                                                                                                                             

13:30         3815.     Optimization of Acquisition and Post Processing Strategies for Deconvolution-Based Perfusion Quantification of Breast Tumors Using T1-Weighted DCE MRI

Computer 69

Smitha Makkat1, Robert Luypaert1, Steven Sourbron2, Tadeusz Stadnik1, Peter Van Schuerbeek1, Martine Dujardin1, Johan De Mey1

1Vrije Universiteit Brussel, Brussels, Belgium; 2University Munich - Grosshadern Hospital, Munich, Germany

Tumor Blood Flow (TBF) assessment can become crucial in anti-angiogenic therapies. The TBF derived using deconvolution analysis of high bolus DCE-MRI were higher than the PET values. Here we explore three key aspects of acquisition/ post processing strategies to improve the accuracy of TBF assessment : contrast dose, FA and tracer concentration estimation. We demonstrate that with the existing high bolus method, simultaneous accomplishment of an unsaturated AIF curve and a tissue curve with adequate SNR can not be met. Instead, use can be made of a prebolus technique in a low FA sequence with RE as the concentration estimate.

 

14:00         3816.     N-Nitrosodiethylamine-Induced Pig Liver Hepatocellular Carcinoma Model: MRI with Gd-BOPTA Enhancement

Computer 69

Yi Xiang Wang1, Xiao Li2, Xiao Ping Zhou2, Cheng Wei Tang2

1The Chinese University of Hong Kong, Shatin, People's Republic of China; 2Sichuan University, West China Hospital, Chengdu, People's Republic of China

Liver HCC with a cirrhosis background was induced in three China Taihu pigs by N-nitrosodiethylamine. Histology and MRI findings of pre- and post- Gd-BOPTA-enhancement showed that all highly, moderately, and poorly differentiated HCC tumors were identified in the pig livers. Gd-BOPTA significantly increased the sensitivity of MRI detection of HCC nodules. That HCC nodules of various differentiations with a variety of MRI signals and enhancement patterns co-exist in the same liver with comparable size to human anatomy provides a versatile animal model both for therapeutic investigation and diagnostic technology development, the latter includes MRI sequence optimization and contrast agent research.

 

14:30         3817.     Monitoring of the Hepatocellular Carcinoma Growth by 1H and 23Na MRI

Computer 69

Andriy Babsky1, Stephen Topper1, Shenghong Ju1, Stacy Bennett1, Gordon McLennan1, Navin Bansal1

1Indiana University, Indianapolis, USA

Water apparent diffusion coefficient (ADC), total tissue Na+ and intracellular Na+ were monitored in hepatocellular carcinoma (HCC) in rats and in the surrounding liver tissue using diffusion weighted 1H, single-quantum (SQ) 23Na and triple-quantum-filtered (TQF) 23Na MRI. The tumor water ADC was ~60% higher compared to the nearby healthy liver tissue but did not change considerably during 28 days of tumor growth (double time ~2.2 days). The HCC growth was associated with an increase in both SQ and TQF 23Na SI especially after 21 days post-cell inoculation reflecting possible changes in intracellular ionic metabolism and in extracellular space.

 

15:00         3818.     Quantification of Tumor Necrosis Using Functional MR Imaging with Pathologic Correlation

Computer 69

Ihab R. Kamel1, Manon Buijs, Josephina A. Vossen, Eleni Liapi, Kwang H. Lee, Michael Torbenson, David A. Bluemke, Jean-Francois H. Geschwind

1Johns Hopkins Hospital, Baltimore, Maryland, USA

This study compares ADC values of Vx-2 tumors implanted in the rabbit liver to the degree of cellular necrosis at careful pathologic correlation. Mean tumor size was 2 cm (SD 0.8 cm), and mean tumor ADC value was 1.98 E -3 mm2/sec.  Mean tumor necrosis at pathology was 49% (CD 24%) as measured by ImageJ software.  The correlation between liver ADC and tumor necrosis at pathology had r value of 0.67 indicating that functional MR imaging using diffusion-weighted acquisitions and ADC values may be used as biomarker of tumor necrosis.

 

13:30         3819.     Dual Blood Supply Model and Analysis for Liver DCE-MRI Studies

Computer 70

James d'Arcy1, Matthew Orton1, Dow-Mu Koh2, Anwar Padhani3, Martin Leach1, David Collins1

1Institute of Cancer Research, Sutton, UK; 2Royal Marsden NHS Foundation Trust, Sutton, UK; 3Mount Vernon Hospital, Northwood, UK

Existing pharmaco-kinetic models used in evaluation of DCE-MRI data rely on a single input function to describe the plasma concentration of contrast agent. The liver, a common site for metastatic disease, is supplied with blood from the hepatic artery and portal vein. Using a dual blood supply, we demonstrate successful model based estimations of the Hepatic Perfusion Index, in addition to conventional pharmaco-kinetic parameters such as Ktrans, ve and kep in both lesions and normal liver. Data analysis and visualization were performed using our software platform (MRIW) designed for the evaluation of DCE-MRI clinical trial data.

 

14:00         3820.     Semi-Automatic Segmentation of Lung Tumors in MRI Images of a Mouse Tumor Model

Computer 70

Johannes T. Heverhagen1,2, Volker Dicken3, Peter Wassenaar1, Georgeta Mihai1, Michael V. Knopp1, Michael A. Pereira1, Petra Schmalbrock1

1The Ohio State University, Columbus, USA; 2Philipps University, Marburg, Germany; 3MeVis, Bremen, Germany

The purpose of this study is to evaluate a semi-automatic tool that measures tumor volume as well as RECIST and WHO assessment criteria after initial seed point placement by an operator. Lung tumor bearing mice were imaged in a 4.7T small animal MRI scanner. The images were analysed using semiautomatic analysis tool. The results show a good correlation with histological tumor volumes. Even tumors located on the diaphragm in close proximity or with contact to the liver were segmented and their volumes were measured correctly. The study demonstrated the feasibility of semi-automatic tumor volumetry in MRI data sets of mouse lung tumors with minima user interaction.

 

14:30         3821.     Comparison of Biodegradable Macromolecular MRI Contrast Agents with Gd-(DTPA-BMA) and Albumin-(Gd-DTPA) in Tumor Characterization with DCE MRI

Computer 70

Yi Feng1, Eun-Kee Jeong, Dennis Parker, Zheng-Rong Lu1

1University of Utah, Salt Lake City, Utah, USA

The effectiveness of the biodegradable macromolecular MRI contrast agents, GDCC and GDCP, in tumor characterization with DCE MRI was evaluated in tumor bearing mice and compared to a low molecular weight contrast agent, Gd(DTPA-BMA), and a non-degradable macromolecular agent, albumin-(Gd-DTPA).  The tumor vascular permeability determined by biodegradable macromolecular contrast agents were similar to that determined by albumin-(Gd-DTPA).

 

15:00         3822.     Multiexponential T2 Analysis of Astrocytoma Cells in Agar

Computer 70

Pamela R. Jackson1, Roland G. Henry2, Tracy R. McKnight2

1University of California, Berkeley and San Francisco, San Francisco, California , USA; 2University of California, San Francisco, San Francisco, California , USA

A well-known characteristic of malignant glioma is an increase in cell density with increasing malignancy of the tumor. We created a simple model for tissue using astrocytoma cells suspended in agar at different densities to better understand the effects of cell density on the T2 signal. Monoexponential, biexponential, and non negative least squares algorithms were used to fit the data, and the Spearman Rank test was used to test correlation . We identified two components associated with agar, the shortest of which dominated the negative correlation of T2 with cell density.

 

Tumor Perfusion & Permeability Measurements

Hall D                                   Wednesday 13:30-15:30                                                                                                                                       

13:30         3823.     Physiologically Based Multiple Reference Tissue Method (PB-MRTM) for Arterial Input Function (AIF) Estimation

Computer 69

Cheng Yang1, Gregory S. Karczmar1, Masoom A. Haider2, Walter M. Stadler1

1University of Chicago, Chicago, Illinois, USA; 2University of Toronto, Canada

We present a method which simultaneously estimates the AIF and physiologic parameters of the patients including the cardiac output (CO) using the contrast agent dynamic data in 2 or more reference tissues obtained from normal tissues and/or tumor sub-regions.  Clinical applications of the PB-MRTM showed that it can provide realistic and consistent estimate of the AIF and CO in both MRI and CT studies, suggesting that it can provide an accurate estimate of the AIF.  On contrast, the AIFs directly measured from arteries in DCE-MRI studies were inaccurate, indicated by that the inferred CO was unrealistically large.

 

14:00         3824.     Systematic Modeling of Perturbations Effects in the Arterial Input Function with Implication for DCE-MRI Evaluation

Computer 69

Dee H. Wu1,2, Rajibul Alam3

1University of Oklahoma Health Science Center, Oklahoma City, USA; 2University of Oklahoma , Norman, USA; 3University of Oklahoma  , Norman, USA

Recently there has been considerable interest surrounding how the arterial input function (AIF) is applied to DCE-MRI analysis which has led to some controversy in the choice of implementation.  We model and evaluate the impact of variation due to injection process (delay and dispersion), and its measurement, and analysis. To model these processes we take independent AIF functions (by modeling its change and predict DCE-MRI variation of pharmacokinetic parameters k12 and k21 and amplitude.  We consider population, individualized curve fits in this analysis.  It appears that with most dramatic changes in pharmacokinetic parameters were illustrated at impulsive positions for time shifts and produce dramatic increases with even moderate changes in dispersion.  This illustrates the potential for large pharmacokinetic changes may occur   even with moderate shifts in time and dispersion of the AIF.

 

14:30         3825.     Feasibility of Using Limited-Population-Based Average R10 for Pharmacokinetic Modeling of Osteosarcoma Dynamic Contrast-Enhanced MRI Data

Computer 69

Wei Huang1,2, Ya Wang1, Jason A. Koutcher1

1Memorial Sloan Kettering Cancer Center, New York, New York, USA

In this DCE MRI study of 18 patients with osteosarcoma, we show that it is feasible, as well as practical, to use a uniform, limited-population-based average  R10 for pharmacokinetic modeling of osteosarcoma DCE MRI data from a larger population when it is not possible to acquire proton density images for individual R1 measurement.

 

15:00         3826.     Sensitivity to Tumor Micro-Vasculature Without Contrast Agents in High Spectral and Spatial Resolution MR Images

Computer 69

Sean Foxley1, Xiaobing Fan1, Devkumar Mustafi1, Chad Haney1, Marta Zamora1, Erica Markiewicz1, Gregory S. Karczmar1

1University of Chicago, Chicago, Illinois, USA

High spectral and spatial resolution (HiSS) datasets of a rodent tumor model were acquired using echo-planar spectroscopic imaging.  Details of the water line for each voxel imaged were analyzed and images were produced.  Pre-contrast HiSS images were compared with a “gold standard for micro-vasculature detection - gradient echo contrast difference images [using a blood pool contrast agent (iron-oxide particles)].  HiSS images were found to have a sensitivity and specificity of 75 ± 13% and 74 ± 10% to tumor micro-vasculature in the tumor rim, respectively.  Results indicate HiSS imaging is sensitive to tumor micro-vasculature without the need of exogenous contrast.

 

13:30         3827.     DCE-MRI Rat Cerebral Glioma Blood Volume Determination with Extravasating CR

Computer 70

Xin Li1, William D. Rooney1, Csanad Varallyay1, James A. Goodman1, Audrey Selzer1, Ian Tagge1, Martin M. Pike1, Edward A. Neuwelt1, Charles S. Springer, Jr.1

1Oregon Health & Science University, Portland, USA

Dynamic-Contrast-Enhanced (DCE) MRI data were obtained from rat brain gliomas that exhibited rapid contrast reagent extravasation.  Despite this, analysis with a three-site-exchange pharmacokinetic model, which admits finite equilibrium water exchange kinetics, allows tumor blood volume determination.  Parameter sensitivity was tested with grid searches of 2D parametric error surfaces.

 

14:00         3828.     Leakage Corrected RCBV Measurements Using Prebolus Dosing:  Applications in Differentiating Glioma Recurrence from Post-Treatment Effect at 3T Field Strength

Computer 70

Leland S. Hu1, Leslie C. Baxter1, Thomas Paine1, John p. Karis1, Burt G. Feuerstein1, Scott Beeman1, Josef Debbins1, James Pipe1, Michael Purcell1, Joseph E. Heiserman

1Barrow Neurological Institute, Phoenix, USA

We set out to determine the necessary preload Gd-DTPA dosage to produce T1W leakage-corrected relative cerebral blood volume (rCBV) values which distinguish glioma recurrence from post-treatment radiation effect (PTRE) using Dynamic Susceptibility Contrast (DSC) MRI at 3T field strength.  rCBV was measured following sequentially increasing preload dosage and correlated directly with surgical tissue specimen histopathology.  We found no significant change in rCBV values over increasing preload dosage.  Possible explanations include decreased T1-weighting at 3T, and effects from steroid therapy, although further work is needed to resolve other possible explanations.

 

14:30         3829.     Dynamic Contrast Enhanced Derived Cerebral Blood Volume Correlates Better with Leak Correction Than with No Correction for Vascular Endothelial Growth Factor, Micro Vascular Density and Grading of Astrocytoma

Computer 70

Mazhar Husain1, Mohammad Haris2, Nuzhat Husain1, Anup Singh3, Savita Srivastava1, Chhitiz Srivastava1, Sanjay Behari2, Ram Kishore Singh Rathore3, Sona Saksena2, Rakesh Kumar Gupta2

1CSMM University, Lucknow, India; 2Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India; 3Indian Institute of Technology, Kanpur, India

Perfusion magnetic resonance imaging has made it possible to assess the microvasculature in-vivo. In this study, quantification of both hemodynamic and physiological indices in 64 cases of astrocytoma was done using dynamic contrast enhanced MRI and correlated with immunohistochemically obtained microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression. The corrected relative cerebral blood volume (rCBV) for leakage of contrast in to interstitium space correlated strongly with MVD, VEGF and grades of astrocytomas compared to the uncorrected rCBV; and was able to classify 100% low grade astrocytoma from high grade astrocytoma precisely

 

15:00         3830.     Molecular Aspects of NMR Shutter-Speed Discrimination of Malignant and Benign Breast Tumors

Computer 70

Charles S. Springer, Jr.1,2, Wei Huang2, Xin Li1, Elizabeth A. Morris2, Luminita A. Tudorica3, William D. Rooney1

1Oregon Health & Science University, Portland, Oregon, USA; 2Memorial Sloan Kettering Cancer Center, New York, New York, USA; 3State University of New York, Stony Brook, New York, USA

In a (Dynamic-Contrast-Enhanced) DCE-MRI study of 22 patients with suspicious breast lesions, Shutter-Speed pharmacokinetic model analysis significantly improved diagnostic specificity compared to the institutional clinical breast MRI protocol.  Specifically, there is an NMR shutter-speed effect on the Ktrans parameter for only the malignant tumors.  Molecular aspects of this are discussed.

 

13:30         3831.     Simultaneous Estimation of T1 and T8* with a 2D Radial Multi Gradient Echo Sequence: Proof of Concept in a Phantom and in Tumor Bearing Mice in the Presence of Respiratory Motion

Computer 71

Julien Vautier1,2, Melanie Heilmann1,2, Christine Walczak1,2, José Manuel Pérez-Sánchez3, Andreas Volk1,2

1Institut Curie, Orsay, France; 2INSERM U759, Orsay, France; 3Universidad Complutense de Madrid, Madrid, Spain

We developed a 2D-radial RF-spoiled multi gradient echo technique on a 4.7T small animal MR system for simultaneous dynamic T1 and T8* estimation at high temporal resolution in experimental tumors. Images (6 echoes, MTX=64) were acquired in 1.3s. T8* was estimated by a monoexponential fit. T1 was estimated from a T8* corrected steady state image combined with prior variable flip angle calibration. Motion artifact free images were obtained without respiratory triggering and reproducible T1 and T8* were obtained in mice and a compartmented phantom. T1 and T8* were validated on the phantom using inversion-recovery and multi gradient echo techniques.

 

14:00         3832.     An Exploration of the Relation Between Angiogenic Status and Susceptibility Contrast in Brain Tumors

Computer 71

Arvind P. Pathak1, Doug Ward2, Kathleen M. Schmainda2

1The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA; 2Medical College of Wisconsin, Milwaukee, Wisconsin, USA

In this study, we employed a novel simulation methodology called the finite perturber model (FPM) that enables us to study susceptibility-induced contrast arising from arbitrary microvascular geometries in 3D, such as those typically observed during tumor angiogenesis. Here, the FPM in conjunction with computer-generated “in silico” 3D tumor microvasculature that conforms to the different stages of brain tumor angiogenesis, was used to explore the relation between angiogenic status and susceptibility-based MR contrast.

 

14:30         3833.     Differential Sensitivity to Vascular Permeability Using Low-MW and High-MW Contrast Agents for DCE-MRI

Computer 71

Hagit Dafni1,2, Sabrina M. Ronen1,2

1The University of Texas M. D. Anderson Cancer center, Houston, USA; 2University of California, San Francisco, USA

The purpose of this study was to compare the sensitivity of low-MW (GdDTPA) and high-MW (albumin-GdDTPA) contrast materials to anti-vascular therapy in a prostate cancer bone metastases model. DCE-MRI performed before and after short-term interventional therapy combining imatinib and paclitaxel, detected significant reduction in permeability to albumin-GdDTPA but not to GdDTPA, reflecting differences in mechanism of vascular permeability and pharmacokinetics of the two agents. This differential sensitivity suggests that development of macromolecular contrast agents for clinical use and their incorporation in clinical DCE-MRI will provide more sensitive and selective detection of early response to some anti-vascular therapies.

 

 

15:00         3834.     Differentiation of Benign Fibroadenomas from Breast Cancer with Dynamic MRI: Comparison of a Novel Macromolecular Contrast Agent and Gadoteridol [Not Available]

Computer 71

Hans Juergen Raatschen1,2, Yanjun Fu2, David M. Shames2, Robert C. Brasch2

1Charite Campus Benjamin Franklin, Berlin, Germany; 2University of California San Francisco Medical Center, San Francisco, California , USA

This animal study was performed to evaluate the suitability of two gadolinium-based contrast agents, the FDA-approved gadoteridol, and a new macromolecular polyethylene glycol (PEG)-based dendrimer, intended for clinical development, for differentiation of benign from malignant breast tumors in an animal model.

The Gd-DO3A-conjugated PEG-core dendrimeric contrast medium PEG12000-Gd-DO3A26 was proven to be superior to the FDA-approved gadoteridol for differentiating benign fibroadenomas from breast cancer based on estimates of tumor fractional plasma volume, fPV, and vascular endothelial leakiness, KPS. The potential for differentiating normal tissues from mammary tumors was similar for both contrast agents.

 

13:30         3835.     Investigating the Influence of Phased Arrays and Parallel Imaging for Input Function Definition in DCE-MRI

Computer 72

Ross A. Little1, Caleb Roberts1, Yvon Watson1, Marietta Scott2, Geoff J. Parker1

1University of Manchester, Manchester, UK; 2AstraZeneca, Macclesfield, Cheshire, UK

Physiologically-meaningful DCE-MRI measurements of microvascular characteristics are not possible without the accurate acquisition of an arterial input function (AIF). This study uses a flow phantom with independent optical measurement to investigate the accuracy of contrast agent concentration measurements taken with dynamic contrast-enhanced MRI using a quadrature body coil and a phased array coil with and without SENSE parallel imaging. Although SENSE factors lead to a reduction in SNR, reduced scan times allow improved measurement of the rapid changes in concentration associated with input function measurement, as confirmed by comparison with our optical measurements.

 

14:00         3836.     The Role of Temporal Resolution in Determining Pharmacokinetic Parameters from DCE-MR Data

Computer 72

Marieke Heisen1, Xiaobing Fan2, Thorsten Twellmann1, Johannes Buurman3, Natal A.W van Riel1, Gregory S. Karczmar2, Bart M. ter Haar-Romeny1

1Technische Universiteit Eindhoven, Eindhoven, Netherlands; 2University of Chicago, Chicago, Illinois, USA; 3Philips Medical Systems, Best, Netherlands

In DCE-MRI of the breast, a wide variety in parameter settings is possible. This especially holds for the temporal resolution of the dynamic series. Given the high expectations of pharmacokinetic modeling, it is crucial to analyze the effect of temporal resolution in determining pharmacokinetic parameters. We investigated this issue by deriving low-temporal-resolution image-series from a high-temporal-resolution original via a reorganization of the k-space data. The initial experiment, as presented here, was performed on data from model tumors in rats. Fitting of the Kety two-compartment pharmacokinetic model demonstrated that with decreasing temporal resolution, Ktrans and ve get progressively under- and overestimated.

 

14:30         3837.     A Method for Updating the Aterial Input Function Each Cardiac Cycle with Flow Compensation

Computer 72

Dustin K. Ragan1, Emilio Esparza-Coss1, James Andrew Bankson1

1M. D. Anderson Cancer Center, Houston, Texas, USA

DCE-MRI is sensitive to the local tissue vascular properties, and has shown promise in monitoring the treatment of disease.  A common approach to quantification is to relate the time course of concentration of a contrast agent in blood and tissue by a model.  Measurement of the blood concentration, or arterial input function (AIF), can be confounded by the cardiac cycle and flow effects.  We measured high temporal resolution AIFs in a mouse by acquiring a projection through the short axis of the heart and compensated for flow effects by combining the excitation pulse with a spatial suppression pulse.

 

15:00         3838.     Novel Procedures to Derive the Impulse Response Function and Its Mathematical Model for DCEMRI

Computer 72

Xiaobing Fan1, Gregory S. Karczmar1

1University of Chicago, Chicago, Illinois, USA

Accuracy of cancer diagnosis with dynamic contrast enhanced MRI (DCEMRI) could be improved by eliminating the arterial input function (AIF) effects and calculating the ‘impulse response function’ (IRF) of the tissue.  Here, we describe a simple and effective deconvolution algorithm and use numerical simulations to study the performance of this algorithm with a variety of contrast concentration vs. time curves.  A general mathematical model of the IRF with physiological parameters relating to blood flow/capillary permeability, and contrast media distribution volume was derived.  The results suggest that the deconvolution procedure developed in this research can be employed to analyze clinical DCEMRI data.

 

Gynecological Cancer

Hall D                                   Thursday 13:30-15:30                                                                                                                                           

13:30         3839.     Apparent Diffusion Coefficient Value for Differentiating Pathology in Cervical Cancer at 3 Tesla

Computer 69

Gigin Lin1, Koon Kwan Ng1, Yau Yau Wai1, Jiun Jie Wang1, Chyong Huey Lai1, Yu Ting Huang1, Kung Chu Ho1, Tzu Chen Yen1

1Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taipei, Taiwan

To investigate the feasibility of using ADC value from 3T MRI for differentiating pathology categories of cervical cancer, 126 patients were enrolled. Mean ADC value of adenocarcinoma (0.96 ± 0.21 x 10-3 mm2/s) was higher than that of squamous cell carcinoma (0.84 ± 0.11 x 10-3 mm2/s), adenosquamous carcinoma (0.79 ± 0.10 x 10-3 mm2/s), or small cell carcinoma (0.53 ± 0.10 x 10-3 mm2/s). Significant difference (p<0.001) was noted between groups. Therefore, ADC value from 3.0T MRI-DWI is promising in differentiating pathology types of cervical cancer.

 

14:00         3840.     High B-Value Diffusion-Weighted MR Images of Uterine Pathologies

Computer 69

Mayumi Takeuchi1, Kenji Matsuzaki1, Hiromu Nishitani1

1University of Tokushima, Tokushima, Japan

We evaluated benign and malignant uterine pathologies by high b-value diffusion-weighted images (DWI) and corresponding isotropic ADC maps. All malignant lesions (44 endometrial cancers/sarcomas: 0.86 +/- 0.20, 5 myometrial sarcomas: 0.78 +/- 0.30 and 34 cervical cancers: 0.91 +/- 0.21) showed very high intensity on DWI. Benign endometrial polyps/hyperplasia (1.58 +/- 0.36) showed iso to intermediate intensity on DWI. However cellular leiomyomas and some degenerated leiomyomas showed high intensity on DWI, benign leiomyomas including these lesions (1.30 +/- 0.28) could be distinguishable from myometrial sarcomas by measuring ADC (p<0.01).

 

14:30         3841.     Diffusion Weighted Imaging of the Uterus : Regional ADC Variation with Oral Contraceptive Usage and Comparison with Cervical Cancer [Not Available]

Computer 69

Christina Messiou1, Veronica A. Morgan1, Sonali S. De Silva1, Nandita M. deSouza1

1The Institute of Cancer Research and The Royal Marsden NHS Trust, Sutton, UK

This study aims to determine ADC values for the normal regions of cervix and uterus and compare them to the ADC value of cervical cancer. The effect of the oral contraceptive pill (OCP) was also investigated.ADCs of cervical tumour are significantly lower than for cervical stroma and epithelium and may be useful in detecting stromal invasion in small lesions. Endometrial ADCs did not change with OCP usage. ADCs of the JZ however did increase with OCP usage. The small patient numbers in this ongoing study meant that these values did not reach significance.

 

15:00         3842.     Changes in TCho/water Ratio in the Transition from Pre-Invasive to Invasive Cervical Cancer Using in Vivo MR Spectroscopic Imaging

Computer 69

Sonali S. De Silva1, Geoffrey S. Payne1, Veronica A. Morgan1, Paul G. Carter2, Thomas E . Ind2, Nandita M. deSouza1

1Institute of Cancer Research and Royal Marsden Hospital NHS Trust, Sutton, UK; 2St Georges Hospital NHS Trust, Tooting Broadway, UK

The development of invasive cervical cancer is preceded by a well-defined pre-invasive stage called cervical intraepithelial neoplasia (CIN). Elevated levels of choline have previously been identified in a number of tumours including cervical cancer but whether these metabolites are elevated in CIN tissue is still unclear. This study investigates changes in the tCho/water ratios in the transition from pre-invasive and invasive cervical cancer. Twenty women (10 women with cervical cancer and 10 women with CIN disease) underwent MR imaging and spectroscopy (TR 888, TE 135 and 4 signal averages). tCho/water was calculated in tumour and non-tumour voxels in cancer patients and voxels close to the endocervix (CIN voxels) and away from the endocervix (non-CIN voxels) in CIN patients. The difference in tCho/water ratio between tumour and CIN voxels was significant (p= 0.004).

 

13:30         3843.     Diffusion MRI Predicts Response in Advance of Tumour Size Changes in Women Receiving Chemoradiation for Cervical Cancer

Computer 70

Vanessa N. Harry1, Scott I. Semple2, David E. Parkin1, Fiona J. Gilbert2

1Aberdeen Royal Infirmary, Aberdeen, UK; 2University of Aberdeen, Aberdeen, UK

Diffusion weighted MRI performed before and after 2 weeks of chemoradiation in women with advanced cervical cancer was found to predict their eventual response. The changes in Apparent Diffusion Coefficient also occurred significantly well before changes in tumour size as determined by conventional radiological assessment. This emphasises the potential of DWI as a biomarker capable of rapid response prediction and its promising use for offering individualised or tailored therapy

 

14:00         3844.     Proton Spectrscopy of Gynaecology Lesions at 3.0T in a Routine Clinical Setting

Computer 70

Martin D. Pickles1, Susanne Booth1, David J. Manton1, Martin lowry1, Julie Pounder1, Dan Siddons1, Lindsay W. Turnbull1

1University of Hull, Hull, UK

A number of groups have revealed an elevated choline peak to be an indicator of malignancy while decreasing choline levels are believed to represent a successful treatment response. In this study single voxel proton spectroscopy of gynaecology lesions were obtained by standard users utilising a 3.0T scanner. Spectra were successfully obtained from a variety of differing gynaecology lesion and the choline signal quantified. This study has demonstrated the feasibility of collecting spectroscopy from gynaecological lesions at 3.0T and the ability to quantity the choline signal by using product spectroscopy sequences by standard users.

 

14:30         3845.     The Utility of Diffusion-Weighted MRI in Cervical Cancer [Not Available]

Computer 70

Patrick Z. McVeigh1, Aejaz M. Syed2, Michael Milosevic1, Anthony Fyles1, Masoom A. Haider1

1Univeristy Health Network, Toronto, Canada; 2The Queen Elizabeth Hospital, King's Lynn, UK

Diffusion-Weighted MRI was performed in 47 patients with cervical cancer (37 squamous carcinoma) undergoing chemoradiation therapy and 26 normal controls on a 1.5T system with a b-value of 600 s/mm2.  Clinical FIGO stage, tumor volume, nodal status, interstitial fluid pressure (IFP) and oxygen measurements were recorded. Response was defined as no visible tumor 3-6 months following completion of therapy.Median ADC in cervix carcinoma is significantly lower compared to normal cervix and may be useful in the delineation of tumor boundaries for therapy planning.  ADC may have predictive value in squamous tumors but further long term study will determine the ultimate clinical utility.

 

15:00         3846.     ADC and Perfusion Signal Fraction Measurements: Feasibility in Ovarian Cancer at 3 Tesla

Computer 70

Andrew Nicholas Priest1, Evis Sala1, Martin John Graves1, Ilse Joubert1, Mary A. McLean2, Nyree Griffin1, John R. Griffiths2, David John Lomas1

1Addenbrooke's Hospital and University of Cambridge, Cambridge, UK; 2Cancer Research UK, Cambridge, UK

Ovarian cancer response to chemotherapy is difficult to predict by standard prognostic factors. We aim to evaluate 3T DWI parameters as surrogate markers of treatment response in ovarian cancer and omental/peritoneal implants; this preliminary study demonstrates the feasibility of the method using multislice DWI data from four patients. Maps of the apparent diffusion coefficient (ADC) and the fractional signal due to perfusion were calculated. All tumours appeared bright on DWI due to their low ADC compared to surrounding tissues. Further work will assess possible correlations between DWI parameters and treatment outcome, and compare the fractional perfusion signal with DCE-MRI.

 

Tumor Assessment & Response

Hall D                                   Thursday 13:30-15:30                                                                                                                                           

13:30         3847.     Relative Changes in Tumor Perfusion (Ktrans, Ve) is Independent of Absolute Baseline T1 Values

Computer 71

Junyu Guo1, Mark A. Rosen1, Hee Kwon Song1

1University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA

In DCE-MRI for tumor assessment, baseline T1 value is required to measure lesion perfusion. However, it can often be difficult to accurately measure T1 due to errors in the flip angle and imperfect slice profile. It is shown in this work that if the relative change in perfusion is of primary interest, e.g. as a result of treatment, the knowledge of the true baseline T1 is not required to accurately quantify these changes.

 

14:00         3848.     Combined Use of DCE-MRI and VSI to Monitor an Antiangiogenic Therapy Against VEGF in Tumor Xenografts

Computer 71

Stefan Zwick1,2, Eva Christina Woenne, Ralph Strecker2, Arne Hengerer2, Matthias Taupitz3, Jörg Schnorr3,4, Magareta Maria Mueller1, Wolfhard Semmler1, Fabian Kiessling1

1German Cancer Research Center, Heidelberg, Germany; 2Siemens Medical Solutions, Erlangen, Germany; 3Charité, Berlin, Germany; 4Ferropharm, Teltow, Germany

VSI in combination with DCE-MRI enables monitoring of early antiangiogenic tumor therapy response. Thus, tumor bearing nude mice were treated with an antiangiogenic VEGF-blocking antibody and investigated by DCE MRI and VSI before and after treatment. The decrease of Amplitude and increase of kep in treated compared to untreated tumors clearly showed therapy response. In contrast, VSI indicated no changes under treatment. Histological analysis showed lower mean vessel area fractions in treated than in untreated tumors but no significant changes in the mean vessel size which again confirms the potential and robustness of VSI and DCE-MRI.

 

14:30         3849.     Evaluation of the Stereotaxis Radiosurgery Effects Using MRI

Computer 71

Marcelo Andia1,2, Cristian Tejos1,2, Claudia Prieto1,2, Leonardo Ramirez1,2, Luis Meneses1,2, Daniel Venencia1, Pablo Irarrazaval1,2

1Pontificia Universidad Catolica de Chile, Santiago, Chile; 2Biomedical Imaging Center, Santiago, Chile

Stereotactic radiosurgery is a form of radiation therapy used to treat tumours in the brain. It consists of a few x-ray beams applied to the patient. To maximise the radiation dose in the tumour, and to minimise the damage in collateral areas, the positions and strength of the beams are given by planning softwares. However, they are not rigorously calibrated because in-vivo tests are not available. We present a method based on T2w-MRI that can be used to identify the radiotherapy effects on the irradiated tissues. This can be used to provide feedback to the planning to improve its accuracy.

 

15:00         3850.     Decreased Choline Levels Detect Response to Rituximab Therapy in WSU-DLCL2 Human Diffuse Large B-Cell Lymphoma Xenografts

Computer 71

Seung Cheol Lee1, David S. Nelson1, Harish Poptani1, Edward James Delikatny1, Jerry D. Glickson1

1University of Pennsylvania, Philadelphia, Pennsylvania, USA

We've performed a longitudinal MRS study on the WSU-DLCL2 human diffuse large B-cell lymphoma xenografts to see the effect of rituximab, a chimeric CD20 antibody, on the MR metabolites of the WSU-DLCL2 tumor. Both the rituximab-only therapy and rituximab plus CHOP (R-CHOP) therapy have been tested and compared with the sham-treated group and the CHOP-alone treated group respectively. tCho has decreased in the groups which have rituximab, while it did not change in the sham-treated or CHOP-alone treated groups. Rituximab induced either tumor growth delay or tumor regression depending on whether it is used alone or used with CHOP. tCho change was observed before effects on the tumor volume.

 

13:30         3851.     Contrast Enhanced MR-Perfusion of Renal Tumors for Monitoring of Neoadjuvant Antiangiogenic Therapy

Computer 72

Mike Notohamiprodjo1, Steven Sourbron, Ulrike Attenberger, Christian Glaser, Gita Schoppler, Maximilian Reiser, Michael Staehler, Karin Herrmann

1University Hospitals Munich, Munich, Germany

The purpose of this study was to analyze renal tumor perfusion with MR-perfusion techniques and to evaluate the potential effects of neoadjuvant therapy on tumor perfusion. Ten patients with normal renal function, 9 patients with RCC before and 4 patients after neoadjuvant antiangiogenic therapy underwent contrast enhanced MR-perfusion. Morphologic and semiquantitative analysis was performed. Distinct morphological changes and perfusion patterns for RCC before and after neoadjuvant antiangiogenic treatment could be described and distinguished. Therefore our preliminary results suggest that contrast enhanced MR-perfusion may become a valuable diagnostic tool to monitor tumor perfusion under antiangiogenic treatment.

 

14:00         3852.     Using Dynamic Contrast Enhanced MRI and Immunohistochemistry to Monitor Tumour Response to Tirapazamine, a Hypoxia-Targeting Chemotherapeutic Agent

Computer 72

Lauren Jean Bains1, Jennifer H. Baker2, Andrew I. Minchinton2, Stefan Alexander Reinsberg1

1University of British Columbia, Vancouver, Canada; 2British Columbia Cancer Research Centre, Vancouver, Canada

The present study is first use of MRI to monitor tumour response to the hypoxia-activated prodrug tirapazamine.  A dramatic decrease in tumour perfusion was seen in the 24 hours after tirapazamine treatment using both dynamic contrast enhanced MRI and carbocyanine staining.  Implanted fiducial markers were used to spatially coregister MRI and immunohistochemistry, resulting in good correlations between the two techniques.  In addition, area under the contrast-time curve (IAUC) was shown to be a potential predictor of tumour response to tirapazamine: tumours with low pre-treatment IAUC showed an improved response to treatment.

 

14:30         3853.     Pre-Clinical Assessment of Anti-Vascular Effects of Novel Combretastatin A-4 Analogues by Dynamic Contrast Enhanced MRI

Computer 72

Inna V. Linnik1, Steve R. Williams1, Karen E. Davies1, Alan T. McGown2, John A. Hadfield2, David L. Buckley1

1University of Manchester, Manchester, UK; 2University of Salford, Manchester, UK

The aim of the study was, firstly, to develop a robust quantitative DCE-MRI protocol for studying tumour vasculature, secondly, to deploy it for evaluation of the effects of novel anti-vascular agents. Five newly synthesized combretastatin analogues, combretastain A-4 (CA-4) and oil as a control were tested for their effects on RIF-1 tumours grown in mice 24 hours after administration.

Three agents, as well as the positive control CA-4, have a significant effect on tumour vascular parameters. The results suggest that the applied DCE-MRI method may be a valuable screening tool to monitor, non-invasively, the effects of anti-vascular drugs in vivo.

 

 15:00         3854.     Diffusion-Weighted MRI as an Early Predictor of Response to Sunitinib

Computer 72

Renu M. Stephen1, Dezheng Zhao, Robert J. Gillies

1University of Arizona, Tucson, Arizona , USA

The early identification of effective cancer treatment combinations minimizes toxicities of ineffective drugs but also provides patients with better overall survival.  Therefore, biomarkers that identify early response to treatment are proving to be more important in the treatment of cancer.  In this study, we evaluated the role of diffusion-weighted (DW) magnetic resonance imaging (MRI) in quantitatively predicting the early response of orthotopic breast xenografts to an antiangiogenic inhibitor, sunitinib. Our results indicate the DW-MRI was able to identify early changes in tumor cellularity following treatment prior to changes in tumor volume.