Electronic Poster Session - Body
  Pulmonary Applications of Advanced Techniques 3957-3980
  Hyperpolarized Gases: Pulmonary Applications 3981-4004
  Contrast-Enhanced Liver MRI 4005-4028
  Diffuse Liver Disease 4029-4052
  Renal MRI 4053-4076
  Body MRI (Miscellaneous & Diabetes) 4077-4100
  Body DWI 4101-4124
  Female Pelvis & Fetal 4125-4148
     

Pulmonary Applications of Advanced Techniques
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  16:00 - 17:00

  Computer #  
3957.   1 Contrast-Enhanced MDCT vs. Time-Resolved MR Angiography vs. Contrast-Enhanced Perfusion MRI: Assessment of Treatment Response by Patients with Chronic Thromboembolic Pulmonary Hypertension (CTEPH)
Yoshiharu Ohno1,2, Mizuho Nishio1, Hisanobu Koyama1,2, Takeshi Yoshikawa1, Sumiaki Matsumoto1, Daisuke Takenaka1, Katsusuke Kyotani2, Nobukazu Aoyama2, Hideaki Kawamitsu2, Makoto Obara3, Marc van Cauteren4, Kenya Murase5, and Kazuro Sugimura1
1Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, 2Radiology, Kobe University Hospital, Kobe, Hyogo, Japan, 3Philips Electronics Japan, Tokyo, Japan, 4Philips Healthcare Asia Pacific, Tokyo, Japan, 5Department of Medical Engineering, Division of Allied Health Sciences, Osaka University Graduate School of Medicine, Suita, Osaka, Japan

 
In the last several years, dynamic CE-perfusion MRI and time-resolved CE-MR angiography have been put forward as new techniques for quantitative and qualitative assessment of pulmonary vascular diseases. However, there have been no reports on the potential of perfusion MRI and time-resolved MR angiography for assessment of therapeutic effects on CTEPH patients. We hypothesized that dynamic CE-perfusion MRI has equal to or better potential for therapeutic assessment than others in CTEPH patients. The aim of our study was therefore to directly compare the therapeutic effect assessment capability of CE-MDCT, time-resolved CE-MR angiography and dynamic CE-perfusion MRI for CTEPH patients.

 
3958.   2 DCE Pulmonary Perfusion Imaging with High Spatial-Temporal Resolution using DISCO
Kang Wang1, Ma. Daniela Cornejo2, Dan W. Rettmann3, James H. Holmes1, A. Muñoz del Río2,4, Frank R. Korosec2,4, Jean H. Brittain1, and Scott K. Nagle2,4
1Global Applied Science Laboratory, GE Healthcare, Madison, WI, United States, 2Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, 3Global Applied Science Laboratory, GE Healthcare, Rochester, MN, United States, 4Radiology, University of Wisconsin-Madison, Madison, WI, United States

 
3D dynamic contrast enhanced (DCE) pulmonary perfusion imaging for simultaneous evaluation of vascular anatomy and a dynamic assessment of parenchymal microvascular enhancement has been a long sought after application and is finally becoming achievable due to recent advances in rapid imaging. However, it poses challenges for the required resolution in the spatial-temporal domain. In this work, we demonstrate the feasibility of using the DISCO (Differential Subsampling with Cartesian Ordering) technique for DCE pulmonary perfusion to achieve the necessary high spatial-temporal resolution for this application.

 
3959.   3 Comparison of CE perfusion, 3He ventilation and oxygen enhanced 1H MRI for Imaging lung ventilation, perfusion and oxygen uptake
Jim M Wild1, Martin H Deppe1, Juan Parra-Robles1, Smitha Rajaram1, David Kiely1, Charlie Elliot1, and Helen Marshall1
1University of Sheffield, Sheffield, Yorkshire, United Kingdom

 
Contrast enhanced (CE) lung perfusion 1H MRI provides volumetric information on pulmonary perfusion. Hyperpolarised 3He MRI provides regional information on ventilation heterogeneity and is sensitive to alveolar oxygen partial pressure. Oxygen enhanced 1H MRI is also sensitive to ventilation and perfusion if it is assumed that the signal enhancement originates from oxygen dissolved in the pulmonary blood compartment. These three complementary functional lung MRI techniques have yet to be tested side by side in-vivo. In this study the methods are compared in a patient with Chronic Thromboembolic Pulmonary Hypertension (CTEPH) whose pulmonary vascular bed shows significant heterogeneity and V/Q mismatch.

 
3960.   4 Assessment of pulmonary perfusion reserve with adenosine using quantitative MRI lung perfusion
Jie Jane Cao1,2, Yi Wang1,3, Kathy Mcgrath1, Nora Ngai1, Joshua cheng1, and Philip Marcus4
1Research, St Francis Hospital, Roslyn, NY New York, United States, 2Cardiology, State University of New York at Stony Brook, Stony Brook, NY New York, United States, 3Bioengineer, State University of New York at Stony Brook, Stony Brook, NY New York, United States, 4Medicine, St Francis Hospital, Roslyn, NY New York, United States

 
We investigated the lung perfusion response to adenosine challenge using lung perfusion quantitation by MRI in 26 volunteers. The absolute lung perfusion was increased by about 2 folds on average during adenosine infusion. Perfusion augmentation was achieved in all lung fields. Reduced lung perfusion was associated with impaired pulmonary function test at rest and during stress. Our findings suggest that quantitative assessment of pulmonary perfusion reserve is feasible using lung perfusion quantitation by MRI.

 
3961.   5 Correlation of DCE-MRI lung perfusion parameter maps with dual-energy CT derived iodine perfusion maps
Jan Hansmann1, Christian Fink1, Frank G. Zoellner2, Thomas Henzler1, Mathias Meyer1, Miriam Reicher1, Gerald Weisser1, Stefan O. Schoenberg1, and Ulrike I. Attenberger1
1Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Mannheim, BW, Germany, 2Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Mannheim, BW, Germany

 
Dual Energy CT allows the generation of iodine perfusion maps. This is however not perfusion imaging in the classical sense but rather a static display of iodine based contrast agent in the lung parenchyma. Correlation of static dual energy CT (DECT) derived iodine maps with parameter maps derived from time resolved quantitative pulmonary perfusion MRI showed a high visual, although not statistically significant, correlation between the two modalities.

 
3962.   6 Ventilation Quantification Using Volumetric Interpolated Breath-hold Examination (VIBE): Preliminary Findings
Yulin V Chang1, James D Quirk1, Francesca Pennati2, Ramsey Hachem3, Andrea Aliverti2, and Jason C Woods1
1Radiology, Washington University, Saint Louis, MO, United States, 2Biomedical Engineering, Politecnico di Milano, Milan, Italy, 3Internal Medicine, Washington University, St. Louis, MO, United States

 
We present our preliminary results on quantification of pulmonary ventilation using proton magnetic resonance imaging (MRI) of the lung at different volumes. Images were acquired at 1.5 T field using volumetric interpolated breath-hold examination (VIBE). The image-intensity differences were computed after image registration as measures of tissue-density changes, which are compared with hyperpolarized 3He images. Our results indicate proton MRI is promising at detecting significant ventilation defects in the lung.

 
3963.   7 Ventilation imaging using DC-navigated oxygen-enhanced 2D-UTE
Simon Triphan1, Felix Breuer1, and Peter Jakob1,2
1Research Centre Magnetic Resonance Bavaria e.V., Würzburg, Germany, 2Experimental Physics 5, University Würzburg, Würzburg, Germany

 
The behaviour of lung T2* under wash-in and wash-out of pure oxygen was measured using a 2D UTE sequence. A time-curve of T2* was produced using golden angle radial sampling and a sliding window technique. By also calculating T2* by navigation using the DC-signal acquired in each trajectory, T2* effects of breathing and oxygen concentration can be separated, increasing the visibility of wash-in and -out. Producing T2* maps for different breathing states using navigation in a single experiment also allows reconstruction of maps for identical breathing states which can be subtracted to give T2* difference maps depending of oxygen concentration.

 
3964.   8 Self-gated time resolved volume (4D) imaging of the human lung under free breathing
Stefan Weick1, Felix A. Breuer2, Martin Blaimer2, Michael Flentje3, Christian Fink4, Lothar R. Schad5, and Peter M Jakob1,2
1Department of Experimental Physics 5, University of Wuerzburg, Wuerzburg, Bavaria, Germany, 2Research Center Magnetic Resonance Bavaria e.V (MRB), 3Department of Radiation Oncology, University Hospital Wuerzburg, 4Department of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, 5Department of Computer Assisted Clinical Medicine, University Medical Center Mannheim

 
In this work, time resolved three dimensional (4D) human lung imaging in high spatial resolution is performed on volunteers as well as patients under free breathing conditions. To this end, the DC signal was acquired every TR and used for gating thereby allowing for the retrospective reconstruction of different respiratory phases. Additionally, a quasi random sampling strategy was employed leading to an increased stability of parallel imaging reconstruction in the case of missing data points due to gating. 4D lung imaging can be used for the assessment of respiratory mechanics and tumor displacement for an individual motion adapted radiotherapy planning.

 
3965.   9 Truncation Artifacts and their Impact on Morphological and Quantitative Lung Imaging
Daniel Stäb1, André Fischer1, Christian Oliver Ritter1, Dietbert Hahn1, and Herbert Köstler1
1Institute of Radiology, University of Würzburg, Würzburg, Germany

 
Pulmonary MRI is well-known to be susceptible to artifacts resulting from cardiac and respiratory motion or flow. In addition however, truncation artifacts or Gibbs ringing introduced at the boundaries between lung and surrounding body tissue are present, especially when imaging with low spatial resolution. In this work, the effects of these Gibbs artifacts on the reconstructed images as well as on quantitative lung parameters like T1 or pulmonary perfusion are demonstrated.

 
3966.   10 Feasibility of 3D radial ultra-short echo time (UTE) MRI of the lungs in healthy subjects
Jeffrey S Nackos1, Kevin M Johnson1,2, Mark L Schiebler1, Christopher J Francois1, Sean B Fain1,2, Maria D Cornejo2, Shane A Wells1, and Scott K Nagle1,2
1Radiology, University of Wisconsin, Madison, Wisconsin, United States, 2Medical Physics, University of Wisconsin, Madison, Wisconsin, United States

 
Evaluation of the lungs using MRI has traditionally been limited by signal loss due to very short T2* and low proton density. Ultrashort echo time (UTE) SPGR imaging can be used to overcome these limitations and has shown promise in recent animal studies. We demonstrate the feasibility of using a respiratory gated 3D radial UTE method on commercially available hardware to evaluate lung structures in healthy human subjects.

 
3967.   11 T2* Measurements of 3 T MRI with Ultra-Short TE: Capability of Assessments for Pulmonary Functional Loss and Disease Severity in Patients with Connective Tissue Disease (CTD)
Yoshiharu Ohno1,2, Mizuho Nishio1, Hisanobu Koyama1,2, Masaya Takahashi3, Takeshi Yoshikawa1, Sumiaki Matsumoto1, Daisuke Takenaka1, Katsusuke Kyotani2, Nobukazu Aoyama2, Hideaki Kawamitsu2, Makoto Obara4, Marc van Cauteren5, and Kazuro Sugimura1
1Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, 2Radiology, Kobe University Hospital, Kobe, Hyogo, Japan, 3Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States, 4Philips Electronics Japan, Tokyo, Japan, 5Philips Healthcare Asia Pacific, Tokyo, Japan

 
CT is most widely used for radiological assessment of disease severity in CTDs. Recently, we have tried to determine the utility of regional T2* measurement in the lung for assessment of pulmonary diseases. We hypothesized that T2* measurement in the lung at 3 T MR system has a potential role to play as a method for assessment of pulmonary functional loss and disease severity in CTD patients. The purpose of this study was to determine the capability of pulmonary MRI with ultra-short TEs (UTEs) in a 3 T system for pulmonary functional and disease severity assessments in patients with CTD.

 
3968.   12 Measurement of Lung Fluid Density Changes using Passive Leg Raising in Congestive Heart Failure
Rexford D Newbould1, Rishi Gupta2, Anura Malaweera2, Andrew Lewis2, Kishan R Parmar2, and Lea Sarov-Blat3
1Imanova Ltd, London, United Kingdom, 2Imperial College London, London, United Kingdom, 3GlaxoSmithKline, Discovery Medicine-Heart Failure DPU

 
Congestive heart failure (CHF) is characterised by an elevated left ventricular end diastolic pressure leading to an increased pressure in pulmonary vasculature, causing fluid to leak into the interstitial spaces of the lung tissue. Continuous HASTE imaging of the right lung was performed in 12 healthy controls (HCs) and 12 subjects with CHF who underwent passive leg raising (PLR). PLR consisted of raising the subject’s legs to a 45° angle while lying in the scanner bore. HASTE acquisitions could map gravity-dependent lung density as well as the response to PLR, although a non-significant difference in lung density response was found between HCs and early-stage CHFs.

 
3969.   13 MR Elastography of Human Lung Parenchyma: Preliminary validation with an interactive respiratory feedback system
Yogesh K Mariappan1, Bryan L Striemer1, David L Levin1, Robert Vassallo2, Richard L Ehman1, and Kiaran P McGee1
1Radiology, Mayo Clinic, Rochester, MN, United States, 2Pulmonary and critical care medicine, Mayo Clinic, Rochester, MN, United States

 
Our overall goal is to develop magnetic resonance elastography (MRE) for the in vivo assessment of human lung. We have recently demonstrated that lung shear stiffness can be spatially resolved in vivo using a 1H pulmonary MRE pulse sequence. The objective of this work was to validate this technique by measuring lung stiffness changes at four different states of respiration including residual volume (RV), total lung capacity (TLC) and two intermediate states in 5 healthy volunteers. In all volunteers shear stiffness increased from RV to TLC and correlated with volume dependent changes in lung stiffness.

 
3970.   14 MR Elastography of Human Lung Parenchyma: Feasibility of Echo-Planar and Respiratory-Triggered Echo-Planar Imaging
Yogesh K Mariappan1, Kevin J Glaser1, Rolf D Hubmayr2, Richard L Ehman1, and Kiaran P McGee1
1Radiology, Mayo Clinic, Rochester, MN, United States, 2Pulmonary and critical care medicine, Mayo Clinic, Rochester, MN, United States

 
We have recently demonstrated that the shear stiffness of human lung parenchyma can be spatially resolved in vivo using spin echo breath-held MR Elastography (MRE) techniques. A disadvantage of this approach is relatively long breath-hold times limiting clinical translation particularly in patients with compromised respiratory function. To address this limitation a respiratory triggered EPI-based MRE sequence has been developed and tested. In vivo data in normal volunteers has demonstrated that changes in lung stiffness throughout the respiratory cycle can be quantified without the need for breath-held acquisitions while still maintaining phase-contrast signal-to-noise ratio compared to breath-held spin echo acquisitions.

 
3971.   15 Quantification of the effects of alveolar surface tension modulation by magnetic resonance elastography (MRE).
Kiaran P. McGee1, Rolf D. Hubmayr2, Yogesh K Mariappan1, Zhonghao Bao3, David L. Levin1, Rickey E. Carter4, and Richard L Ehman1
1Radiology, Mayo Clinic & Foundation, Rochester, Mn, United States, 2Pulmonary and Critical Care Medicine, Mayo Clinic & Foundation, Rochester, Mn, United States, 3Information Technology, Mayo Clinic, Rochester, Mn, United States, 4Health Sciences Research, Mayo Clinic, Rochester, Mn, United States

 
Pulmonary surfactant is lipoprotein complex responsible for decreasing surface tension at the alveolar air-fluid interface, is a known moderator of lung elastic recoil and a major contributor to lung stiffness. While surfactant can be assayed by bronchiolar lavage its spatial distribution and effects on lung stiffness cannot be directly quantified. We present first data demonstrating that magnetic resonance elastography (MRE) can quantify both global and regional changes in lung elastic recoil caused by loss of surfactant in a flooded lung. Regional increases in MRE-based lung stiffness with inflation pressure suggest that MRE can also predict areas of active recruitment.

 
3972.   16 UTE MRI investigation of a chronic asthma mouse model: quantification of peribronchovascular inflammation and correlation with airways hyperresponsiveness
Andrea Bianchi1, Gerard Raffard2, Olga Ousova1, Annaïg Ozier1, and Yannick Crémillieux1
1Centre de Recherche Cardio-Thoracique de Bordeaux, Université Bordeaux Segalen, Bordeaux, France, 2Centre de Résonance Magnétique des Systèmes Biologiques, Université Bordeaux Segalen, Bordeaux, France

 
In this study we present the MRI investigation of a realistic model of asthma in mice (ovalbumin sensitization without aluminum hydroxide), mimicking the first steps in the development of the disease in humans. The small peribronchovascular inflammation, almost three times less than in the models with alum, was visualized and quantified thanks to the improvements over the typical lung images allowed by the use of an Ultra-Short Echo Time (UTE) sequence; the inflammation was also correlated with the enhanced pause of the mice measured with a plethysmograph, an important means of quantification of airways hyperresponsiveness in mice.

 
3973.   17 Gadolinium Contrast Enhanced Ultra-Short TE Imaging of Lung in Mice
Liya Wang1,2, Xiaodong Zhong3, Xianghong Peng4, Jing Huang1,2, Xiaofeng Yang5, and Hui Mao1,2
1Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia, United States, 2Center for Systems Imaging, Emory University School of Medicine, Atlanta, Georgia, United States, 3MR R&D Collaborations, Siemens Healthcare, Atlanta, GA, United States, 4Emory Winship Cancer Institute, Emory University, Atlanta, Georgia, United States, 5Radiation Oncology, Emory University School of Medicine, Atlanta, Georgia, United States

 
This study investigated the feasibility of gadolinium contrast agent enhanced UTE MRI of lung in mice on a standard 3 Tesla clinical MRI system with the goal to improve the image quality of pulmonary MRI. The results demonstrated that the administering gadolinium contrast agent combining with UTE acquisitions provide the high sensitivity and image contrast in MRI of lung. The gadolinium contrast enhanced UTE MRI of lung is dose-dependent and can be optimized.

 
3974.   18 Similar T1 changes are found in a translational study in the lungs of human smokers and mice exposed to tobacco smoke
Daniel Alamidi1, Penny L Hubbard2,3, Deirdre M McGrath4, Jelena Pesic5, Magdalena Zurek5, Malin J Gustavsson5, Charlott Brunmark6, Josephine Naish2,3, Lars E Olsson1,5, and Geoff J Parker2,3
1Department of Radiation Physics, The University of Gothenburg, Gothenburg, Sweden, 2Imaging Sciences and Biomedical Engineering, The University of Manchester, Manchester, United Kingdom, 3The Biomedical Imaging Institute, The University of Manchester, Manchester, United Kingdom, 4Radiation Medicine Program, Princess Margaret Hospital, Toronto, Canada, 5AstraZeneca R&D, Mölndal, Sweden, 6Truly Translational Sweden, Lund, Sweden

 
In this study MR imaging was used to study the effects of tobacco smoke on lungs. Experiments were performed on both human smokers and mice exposed to tobacco smoke. T1 changes in the lungs were found in both human smokers and tobacco smoke exposed mice. A translational link between humans and animals exposed to tobacco smoke expressed as decreased T1 has been demonstrated. Using MRI tobacco exposed animals may be a translational animal model of COPD.

 
3975.   19 Accurate T1 mapping in rodent lungs using ultrashort echo-time MRI
Magdalena Zurek1, Daniel Alamidi1, Edvin Johansson1, Frank Risse1, and Lars E Olsson1
1Personalised Healthcare and Biomarkers, Imaging, AstraZeneca R&D, Mölndal, Sweden

 
A robust method for accurate assessment of T1 in rodent lungs was implemented. The sequence (segmented 2D-IR with ultrashort echo-time (UTE) and radial k-space sampling) was validated via simulations, and sequence parameters were optimized in a phantom study. The presented technique enables the T1 of pulmonary structures to be mapped with a high spatial resolution. The protocol has the potential to assess lung properties relevant in various animal models of pulmonary disorders.

 
3976.   20 Real-time Lung MRI of the Mouse
Amir Moussavi1,2, Martin Uecker1,3, Tilman Johannes Sumpf1, Roland Tammer1,2, Jens Frahm1, and Susann Boretius1,4
1Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut fuer biophysikalische Chemie, Goettingen, Germany, 2DFG Research Center for Molecular Biology of the Brain (CMPB), Goettingen, Germany, 3Electrical Engineering and Computer Science, University of California, Berkeley, United States, 4Klinik für Diagnostische Radiologie, Universitätsklinikum Schleswig-Holstein, Kiel, Germany

 
To avoid the necessity of cardiorespiratory gating, lung MRI of the mouse requires short acquisition times. The combination of highly under-sampled radial FLASH with a nonlinear inverse image reconstruction algorithm allowed for a temporal resolution of 100 ms per image of the mouse lung at a sufficient spatial resolution. Moreover, the lung parenchymal motion and the up and down movement of the thoracic diaphragm were clearly visible while breathing, offering the possibility to monitor breathing irregularities or fast, single-events such as rapid short-term responses to medications.

 
3977.   21 Monitoring of Cryptococcus lung infection with IntraGate MRI
Greetje Vande Velde1, Tom Dresselaers1, Eric Verbeken2, Katrien Lagrou3, and Uwe Himmelreich1
1Biomedical NMR unit/ MoSAIC, KU Leuven, Leuven, Flanders, Belgium, 2Morphology and Molecular Pathology, UZ Leuven, Leuven, Flanders, Belgium,3Experimental Laboratory Medicine, UZ Leuven, Leuven, Flanders, Belgium

 
Cryptococcus is an encapsulated yeast that causes life-threatening disease. Cryptococcosis mostly affects the lung of a host and may spread to the brain, but this pathogenesis is still largely enigmatic. For the first time we were able to visualize onset and progression of pneumonial cryptococcosis with IntraGate MRI, long before symptomatic disease ocurred. Being able to dynamically follow-up disease progression will greatly enhance cryptococcosis research, as MRI can identify the relevant time frame for molecular and histological analysis of BBB crossing of cryptococs with very good time resolution.

 
3978.   22 Diaphragm Motion Control in fast MRI using Audiovisual Biofeedback
Taeho Kim1, Michael Graf2, Elaine Ryan3, and Paul Keall1
1Radiation Physics Laboratory, Unviersity of Sydney, Camperdown, NSW, Australia, 2GE Healthcare, 3Unviersity of Sydney

 
40% of lung cancer patients receive radiotherapy as part of their treatment. Involuntary respiratory motion can compromise treatment quality by decreasing image quality and lowering tumor control (4-5% dose variation per 5 mm tumor excursion). The aim of this study is to develop a novel respiratory motion control system using audiovisual (AV) biofeedback combined with chest MRI to improve diaphragm motion reproducibility, increasing respiratory gating efficiency and reducing motion artifacts in MRI.

 
3979.   23 Multi-Phase Transmission RF Systems: Utility for improvement of B1 Inhomogeneity and Image Quality on 3T MR System as compared with Single- and Multi-Transmit RF Systems
Katsusuke Kyotani1, Yoshiharu Ohno1,2, Nobukazu Aoyama1, Hideaki Kawamitsu1, Takeshi Yoshikawa2, Satoru Takahashi2, Hisanobu Koyama2, Mizuho Nishio2, Sumiaki Matsumoto2, Saori Satou3, and Kazuro Sugimura2
1Radiology, Kobe University Hospital, Kobe, Hyogo, Japan, 2Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, 3Toshiba Medical Systems, Ohtawara, Tochigi, Japan

 
Multi-transmit (i.e. 2-channel 2-port) and multi-phase transmission (i.e. 2-channel 4-port) techniques may be one of the solutions for improving image quality and capability of 3T MR system not only chest MR imaging, but also other body MR imaging. We hypothesized that multi-phase transmission RF system could improve B1 inhomogeneity and image quality on basic and clinical studies as compared with single-transmit and multi-transmit RF systems. The purpose of this study was to directly and prospectively compare B1 homogeneity and image quality of chest MR imaging among three different RF systems on 3T MR system.

 
3980.   24 Automatic Segmentation of Lung Parenchyma using Fuzzy Clustering
André Fischer1, Christian Oliver Ritter1, Dietbert Hahn1, and Herbert Köstler1
1Institute of Radiology, University of Wuerzburg, Wuerzburg, Germany

 
This work describes the ability of Fuzzy C-Means (FCM) clustering to accurately distinguish between pulmonary parenchyma, pulmonary vessels, the heart, and the surrounding tissue in dynamic contrast enhanced (DCE)-MRI. FCM clustering achieves this by clustering voxels with similar temporal signal courses together. A 3D DCE-MRI dataset was accordingly segmented and is presented in this work. This technique enables user independent automatic segmentation of the lung parenchyma necessary to quantify lung perfusion. Thereby, a subjective bias in data analysis as often present in manual parenchyma segmentation is lowered.
 
Electronic Poster Session - Body

Hyperpolarized Gases: Pulmonary Applications
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  17:00 - 18:00

  Computer #  
3981.   1 Mapping of 129Xe Apparent Diffusion Coefficient Anisotropy in Radiation-Induced Lung Injury
Elaine Hegarty1,2, Alexei V Ouriadov1, Matthew S. Fox1,2, Eugene Wong2,3, Ian D. Welch4, and Giles E. Santyr1,3
1Imaging Research Laboratories, John P. Robarts Research Institute, London, Ontario, Canada, 2Physics and Astronomy, University of Western Ontario, London, Ontario, Canada, 3Medical Biophysics, University of Western Ontario, London, Ontario, Canada, 4Animal Care and Veterinary Services, University of Western Ontario, London, Ontario, Canada

 
Magnetic Resonance (MR) imaging of hyperpolarized noble gases (3He and 129Xe) provides anatomical and functional information about the lungs. Apparent diffusion coefficient (ADC) in the lung is anisotropic and can be described by two components; (i) a longitudinal coefficient (DL) representing diffusion along the terminal bronchiole and (ii) a transverse coefficient (DT) representing diffusion perpendicular to the terminal airway. 129Xe ADC anisotropy was mapped in the lungs of a cohort of rats receiving irradiation and compared to histology. Radiation induced lung injury (RILI) was observed in ADC maps as well as histology.

 
3982.   2 Optimal Conditions for Accelerated Imaging of Fractional Ventilation with Hyperpolarized Gas MRI
Kiarash Emami1, Yinan Xu1, Hooman Hamedani1, Harrilla Profka1, Yi Xin1, Puttisarn Mongkolwisetwara1, Stephen J. Kadlecek1, Masaru Ishii2, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Otolaryngology - Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States

 
Accelerated imaging of fractional ventilation by parallel imaging effectively reduces the total imaging time and the overall RF-induced signal decay. This in turn improves the accuracy of fractional ventilation measurements, while allowing for a more similar respiratory pattern during HP gas MRI to that of normal breathing. Given the multitude of parameters that define an accelerated imaging protocol (e.g. flip angle and acceleration factor), an objective analysis of these effects can assist in selecting an optimal set of parameters to minimize estimation error while maintaining study requirements.

 
3983.   3 Regional Measurement of Respiratory Gas Arrival Time with Hyperpolarized Gas MRI
Kiarash Emami1, Yi Xin1, Puttisarn Mongkolwisetwara1, Harrilla Profka1, Jennia Rajaei1, Stephen J. Kadlecek1, Masaru Ishii2, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Otolaryngology - Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States

 
Introduction of controlled pre-acquisition time delay in the existing fractional ventilation imaging technique provides a tool for determining regional gas arrival time constant, with a fairly similar implication to lung RC time constants on a regional basis. Results can alternatively be utilized to select a proper pre-acquisition time delay to minimize motion-induced errors and well mixing of inspired and residual gases in standard specific ventilation imaging applications with HP gas MRI.

 
3984.   4 Positive End Expiratory Pressure (PEEP) and Surfactant Administration Decrease Airspace Dilatation in Ventilated Rats after Pulmonary Saline Lavage
Maurizio Cereda1, Yi Xin2, Kiarash Emami2, Stephen J. Kadlecek2, Puttisarn Mongkolwisetwara2, Harrilla Profka2, Stephen Pickup2, Clifford S. Deutschman1, and Rahim R. Rizi2
1Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, PA, United States, 2Radiology, University of Pennsylvania, Philadelphia, PA, United States

 
Surfactant depletion causes atelectasis and predisposes subjects to ventilator associated lung injury due to harmful pulmonary airspace dilatation, as detected by increased 3He apparent diffusion coefficient (ADC). Utilizing positive end expiratory pressure and surfactant administration as alveolar recruitment techniques could protect the lungs from injury. The presented result in rats shows that the combination of these two techniques synergistically restores normal airspace size by the effect of reducing ADC value to baseline.

 
3985.   5 Assessment of Pulmonary Inflammation in a Rat Bleomycin Model using Oxygen-weighted Hyperpolarized 3He MRI
Puttisarn Mongkolwisetwara1, Milton Rossman2, Evguenia Arguiri2, Harrilla Profka1, Kiarash Emami1, Yi Xin1, Stephen J. Kadlecek1, Melpo Christofidou-Solomidou2, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Medicine, University of Pennsylvania, Philadelphia, PA, United States

 
Idiopathic Pulmonary Fibrosis (IPF) is a fatal lung disease. It causes scarring of the lungs and limits oxygen transport across membranes into bloodstream. The disease course of IPF is variable. In this work, hyperpolarized (HP) 3He MRI is used to acquire regional information of oxygen tension, oxygen uptake and fractional ventilation in a rat model of interstitial fibrosis secondary to bleomycin. Significant correlation between oxygen uptake and biological markers of inflammation and fibrosis in lung suggests that the oxygen-weighted HP MRI can be used as a tool for early detection of fibrosis development and evaluate disease progress in humans.

 
3986.   6 Imaging Structural Changes in Mice Lungs After Long-term Exposure to Cigarette Smoke
Yi Xin1, Kiarash Emami1, Puttisarn Mongkolwisetwara1, Harrilla Profka1, Garrett Greenan2, Stephen J. Kadlecek1, Stephen Pickup1, Brian J. Bolognese3, Edward R. Long III3, Joseph P. Foley3, Patricia L. Podolin3, Masaru Ishii4, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2University of Pennsylvania, Philadelphia, PA, United States, 3Respiratory Therapeutic Area, GlaxoSmithKline, King of Prussia, PA, United States, 4Otolaryngology - Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States

 
Changes in pulmonary microstructure are examined in mice chronically exposed to cigarette smoke using HP 3He diffusion MRI.The smoked mice show significantly larger 3He ADC values both at high and low pulmonary pressure levels reflecting enlarged size of alveolar and small airways, as well as a higher growth rate of ADC as a function of pressure illustrating larger compliance. These results are supported by histology. We conclude that 3He ADC can serve as a useful biomarker to elucidate underlying remodeling of lung tissue resulting from smoking.

 
3987.   7 The Effect of Lung Inflation on the T2* of 129Xe in the Human Lungs at 1.5 T and 3 T
Xiaojun Xu1, Graham Norquay1, Helen Marshall1, Juan Parra-Robles1, and Jim M. Wild1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom

 
T2* of hyperpolarised 129Xe is largely affected by the magnetic susceptibility at the tissue/air interfaces within the lungs. Initial results at forced residual volume (FRV) + 1 l are reproducible, yet shorter than the only other previously reported values in the conference literature. Repeated measurements with the lungs filled up with room air to total lung capacity (TLC) instead of FRV + 1 l coincide with previous results of T2* values, indicating a significant dependence of the transverse relaxation constant T2* on lung inflation volume.

 
3988.   8 Hyperpolarized 129 Xe Apparent Diffusion Coefficient Anisotropy in Chronic Obstructive Pulmonary Disease
Alexei V Ouriadov1, Adam Farag1, Miranda Kirby1,2, David G McCormack3, Grace Parraga1,4, and Giles E Santyr1,2
1Imaging Research Laboratories, Robarts Research Institute, The University of Western Ontario, London, Ontario, Canada, London, Ontario, Canada,2Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada, London, Ontario, Canada, 3Division of Respirology, Department of Medicine, The University of Western Ontario, London, Ontario, Canada, London, Ontario, Canada, 4Department of Medical Imaging, The University of Western Ontario, London, Ontario, Canada, London, Ontario, Canada

 
The availability of large volumes (up to 2 L) of highly polarized 129Xe gas provides a way to conduct multiple b value measurements of the 129Xe ADC in human subjects for the quantitative evaluation of lung tissue microstructure. In contrast with the single exponential ADC method, xenon diffusion anisotropy may be studied with a multiple b value approach, yielding transverse and longitudinal diffusion coefficients. In this pilot study, we explore the potential of 129Xe MRI for the evaluation of diffusion anisotropy changes in a small group of COPD subjects compared to healthy volunteers.

 
3989.   9 Hyperpolarised 129Xe gas lung MRI – B0 field strength comparisons at 1.5 T and 3 T
Xiaojun Xu1, Graham Norquay1, Steven R. Parnell1, Martin H Deppe1, Salma Ajraoui1, Ralph Hashoian2, Helen Marshall1, Paul Griffiths1, Juan Parra-Robles1, and Jim M. Wild1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom, 2Clinical MR Solutions, United States

 
In this study, the SNR of hyperpolarised 129Xe human lung MRI was compared at 1.5 T and 3 T. Experiments were performed at both B0 fields with quadrature double Helmholtz transmit-receive chest coils of the same geometry. Differences in sensitivity between the two RF receiver systems and body coils that are due to factors not directly related to field strength were assessed and normalised by using a thermally-polarised 129Xe phantom. There were no significant differences observed in image SNR of 129Xe ventilation lung images obtained at the two field strengths.

 
3990.   10 A Metastability Exchange Optical Pumping (MEOP) high field polarizer for helium-3 working in a clinical scanner
Guilhem Collier1, Tadeusz Palasz1, Bartosz Glowacz1, Anna Wojna1, Zbigniew Olejniczak2, Mateusz Suchanek3, and Tomasz Dohnalik1
1Jagiellonian University, Krakow, Malopolska, Poland, 2Polish Academy of Sciences, Krakow, Malopolska, Poland, 3Agricultural University of Cracow, Krakow, Malopolska, Poland

 
Imaging of air spaces in the lungs with magnetic resonance became possible thanks to the use of hyperpolarized noble gases such as helium-3. MEOP process has been studied by our group for several years in non-standard conditions (magnetic field > 0.5T and pressures > 10mbar) in order to increase its efficiency. Following the promising results obtained during these systematic studies (the production rate being improved by an order of magnitude compared to the best results obtained in standard conditions), a prototype of high field polarizer working inside a medical scanner at 1.5T was designed and successfully used for human lung MRI.

 
3991.   11 Optimizing Single-Breath Xenon Transfer Contrast MRI: Experimental Results, Theory, and Stochastic Modeling
Eric Frederick1,2, Iga Muradian3, Natalia Lisitza3, Mike Dabaghyan2, Mirko Hrovat4, and Samuel Patz3
1Brigham and Women's Hospital, Melrose, MA, United States, 2Mirtech Inc., 3Brigham and Women's Hospital, 4Mirtech, United States

 
We determined the optimal parameters for SB-XTC using both Monte Carlo simulations as well as the analytic solution. These results were directly compared with our experimental data and we observed an offset that is comparable to what is expected from physiological variations. Unlike previous reports, we considered the effect of the phase encoding pulses and determined that uncertainty in the measured values can be reduced by 82.3% if the in-plane resolution is halved.

 
3992.   12 Repeatability Study of Regional Measurements of Alveolar Oxygen Tension in Humans by Hyperpolarized 3He MRI
Hooman Hamedani1, Masaru Ishii2, Kiarash Emami1, Stephen J. Kadlecek1, Yi Xin1, Puttisarn Mongkolwisetwara1, Nicholas N. Kuzma1, Biao Han1, Harrison McAdams3, G. Wilson Miller4, Milton Rossman5, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Otolaryngology - Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States, 3Biological Basis of Behavior Program, University of Pennsylvania, Philadelphia, PA, United States, 4Radiology, University of Virginia, Charlottesville, VA, United States, 5Medicine, University of Pennsylvania, Philadelphia, PA, United States

 
Four healthy non-smokers and four asymptomatic smokers underwent three repetitions of hyperpolarized 3He MRI imaging in a two-week period to obtain a measure of intraclass test-retest repeatability for an oxygen-weighted 3He MRI scheme to measure the regional alveolar partial pressure of oxygen. 12 slices were imaged during a 12-second breath-hold with a reasonable spatial resolution. Inter and intraclass repeatability was measured for both global and regional distributions of partial pressure of oxygen in subjects. A mixed-effect model with random effects was regressed to 3x3x3 cm3 voxels of all human subjects to estimate a correlation coefficient for each group.

 
3993.   13 The influence of diffusion time on the measurement of the short-range 3He diffusivity in human lungs
Juan Parra-Robles1, Martin H Deppe1, Xiaojun Xu1, Helen Marshall1, and Jim M Wild1
1Academic Unit of Radiology, University of Sheffield, Sheffield, United Kingdom

 
In this work, the effect of diffusion time on 3He ADC is investigated through experiments with healthy human volunteers. The results of this work show that the short-range ADC of 3He gas in human lungs decreases with increasing diffusion time, while its degree of non-monoexponentiality remained constant in the range 1.4-2.5 ms. The results demonstrate that the cylinder model produces inaccurate estimates of the airway dimensions as a consequence of incompletely accounting for the diffusion-time dependence in the model equations.

 
3994.   14 Comparison of Pulmonary Function Testing with Distribution of Alveolar Oxygen Tension and Apparent Diffusion Coefficient in Asymptomatic Smokers Using Hyperpolarized 3He MRI
Hooman Hamedani1, Kiarash Emami1, Stephen J. Kadlecek1, Yi Xin1, Puttisarn Mongkolwisetwara1, Biao Han1, Harrison McAdams2, Masaru Ishii3, G. Wilson Miller4, Milton Rossman5, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Biological Basis of Behavior Program, University of Pennsylvania, Philadelphia, PA, United States, 3Otolaryngology - Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States, 4Radiology, University of Virginia, Charlottesville, VA, United States, 5Medicine, University of Pennsylvania, Philadelphia, PA, United States

 
Ten healthy non-smokers and twenty asymptomatic smokers participated in a hyperpolarized 3He ADC and pAO2 MRI imaging. 12 slices with thickness of 13mm were acquired for each subject during 12-second breath-hold with a reasonable spatial resolution. Before each MRI session, a pulmonary function test was performed. Imaged ADC and pAO2 distributions of whole-lung were regressed on PFT results and ANNOVA test was performed to study the power of discriminatory of MRI metrics in distinguishing the smokers from nonsmokers.

 
3995.   15 Parallel Accelerated Imaging of Alveolar Partial Pressure of Oxygen
Stephen J. Kadlecek1, Yinan Xu1, Kiarash Emami1, Yi Xin1, Puttisarn Mongkolwisetwara1, Hooman Hamedani1, Harrison McAdams2, Masaru Ishii3, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Biological Basis of Behavior Program, University of Pennsylvania, Philadelphia, PA, United States, 3Otolaryngology - Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States

 
An improved method to image PAO2 maps in human lungs is proposed using parallel accelerated HP 3He MRI. Using computational models and phantoms it is shown that when used effectively, accelerated undersampled imaging can lead to a more accurate measure of oxygen tension in the lungs. Technique feasibility and advantage is demonstrated in a healthy human subject. The improvement in PAO2 accuracy is linked to the more efficient use of the finite polarization of HP gas and by increased weighting of the O2-induced contrast versus RF-induced signal decay. Potential confounding factors, e.g., image artifacts or blurring due to accelerated reconstruction, are not observed in this study.

 
3996.   16 Elevated short-time-scale hyperpolarized helium-3 diffusion in secondhand smokers
Chengbo Wang1, John P Mugler, III1,2, Eduard E de Lange1, and Talissa A Altes1
1Radiology and Medical Imaging, University of Virginia, Charlottesville, Virginia, United States, 2Biomedical Engineering, University of Virginia, Charlottesville, Virginia, United States

 
Short-time-scale(STS) and long-time-scale(LTS) helium-3 diffusion were measured in 21 controls, 28 secondhand-smokers and 19 smokers. The STS and LTS ADC values of smokers were significantly elevated compared to controls and secondhand-smokers (P < 0.001 both). One-Way ANOVA analysis indicated that the mean STS ADC values from secondhand-smokers was significantly elevated compared with that of controls (increase for 10.2%, P=0.007) while not for the LTS ADC (increase 13.2%, P=0.238).

 
3997.   17 Quantitative Multi-Breath Fractional Ventilation Imaging in Voluntarily Breathing Humans
Kiarash Emami1, Hooman Hamedani1, Biao Han1, Yinan Xu1, Stephen J. Kadlecek1, Masaru Ishii2, and Rahim R. Rizi1
1Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Otolaryngology - Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States

 
The feasibility of performing multi-breath fractional ventilation hyperpolarized gas MRI in human subjects are demonstrated. This methodology is the first to report a quantitative measure of respiratory gas distribution and replacement in human lungs. The detailed mechanisms of gas transport in lungs with heterogeneous ventilation defects require further investigation to explain the reflections on fractional ventilation values before proper interpretation can be made. Nevertheless fractional ventilation can now be evaluated as a quantitative regional marker to investigate heterogeneous obstructive lung diseases.

 
3998.   18 Evaluation of the Apparent Diffusion Coefficient for Hyperpolarized Helium-3 in the Lung at 0.4T and 1.5T
Peter Komlosi1, Talissa A. Altes1, Karen E. Mooney2, G. Wilson Miller1, Jaime F. Mata1, Eduard E. de Lange1, William A. Tobias2, Gordon D. Cates Jr.2, and John Mugler III1
1Department of Radiology, University of Virginia, Charlottesville, VA, United States, 2Department of Physics, University of Virginia, Charlottesville, VA, United States

 
The goal of the present study was to evaluate the field-strength dependence of He3 ADC values at 0.4T and 1.5T. We found that for each of three orthogonal diffusion-sensitization directions, ADC values for the healthy human lung based on 2 b-value measurements were typically a few percent smaller at 0.43T than at 1.5T, and that these differences were statistically significant.

 
3999.   19 Imaging of Pulmonary Ventilation and Gas Exchange with Hyperpolarized 129Xe in Mouse Models of Chronic Obstructive Pulmonary Disease Induced by Cigarette Smoke Solution and Lipopolysaccharide
Hirohiko Imai1, Hironobu Matsumoto1, Yurika Miyakoshi1, Daichi Takemori1, Shinya Nakasone1, Susumu Yamamoto1, Hideaki Fujiwara1, and Atsuomi Kimura1
1Department of Medical Physics and Engineering, Division of Health Sciences, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan

 
We investigated the feasibility of quantitative assessment of pulmonary functions with hyperpolarized (HP) 129Xe MRI in spontaneously breathing mice. Pulmonary ventilation and gas exchange were regionally evaluated in a mouse model of chronic obstructive pulmonary disease (COPD) induced by multiple administration of cigarette smoke solution (CSS) combined with lipopolysaccharide (LPS). Significant dysfunctions of ventilation and gas exchange in CSS+LPS-treated mice were observed. Thus, it was shown that this methodology is sensitive to differences in these pulmonary functions between the newly developed COPD models and controls.

 
4000.   20 Dynamic Radial Imaging of Inhaled 129Xe and 3He
Helen Marshall1, Xiaojun Xu1, Graham Norquay1, Steve R Parnell1, Juan Parra-Robles1, and Jim M Wild1
1Academic Radiology, University of Sheffield, Sheffield, South Yorkshire, United Kingdom

 
Dynamic radial 3He imaging allows rapid imaging of gas flow and can give information about lung motion and gas trapping. 129Xe and 3He dynamic radial imaging of an inhalation and exhalation manoeuvre were compared in a healthy volunteer. Comparable lung movement and gas filling was seen, despite the lower signal to noise ratio of the 129Xe images. Region of interest signal time-courses showed a faster rate of signal increase during inhalation for 3He than129Xe, which may be due to the greater density of 129Xe. The rate of signal decay during exhalation was similar for both gases.

 
4001.   21 Assessment of Repeatability of Hyperpolarized Gas MR Ventilation Imaging in Cystic Fibrosis Patients
Marcus John Couch1, Brian O'Sullivan2, John Roche1,3, Ronn Walvick3,4, Shaokuan Zheng3, Dawn Baker2, Mac Johnson5, Martyn Botfield5, and Mitchell Albert1,6
1Thunder Bay Regional Research Institute, Thunder Bay, Ontario, Canada, 2Department of Pediatrics, University of Massachusetts Medical School, MA, United States, 3Department of Radiology, University of Massachusetts Medical School, MA, United States, 4Center for Biomedical Imaging, New York University Langone Medical Center, NY, United States, 5Vertex Pharmaceuticals Incorporated, MA, United States, 6Department of Chemistry, Lakehead University, Thunder Bay, Ontario, Canada

 
Hyperpolarized gas MRI provides high-resolution regional information on lung function, offering promise as a valuable outcome measure for cystic fibrosis (CF) and other pulmonary diseases. Using advanced quantitative analyses, we examined repeatability of 3He MR images of five CF patients over several weeks. A pulmonologist read the images, and ventilation volume was determined using an advanced semiautomatic segmentation algorithm. Total ventilation volume was statistically consistent over time. A pixel-by-pixel analysis, however, did show statistical differences. Our results indicate that investigators will need to evaluate the level of sensitivity to use when applying this technology to disease staging and therapy evaluation.

 
4002.   22 Long-time-scale hyperpolarized Helium-3 diffusion MRI: global versus regional measurements
Chengbo Wang1, John P Mugler, III1, Eduard E de Lange1, and Talissa A Altes1
1Radiology and Medical Imaging, University of Virginia, Charlottesville, Virginia, United States

 
Global ADC values and regional ADC maps of hyperpolarized helium-3 in human lungs were measured at the long-time-scale in 19 healthy subjects and 19 smokers. For smokers, global ADC increased 107% (P<0.01) while mean of regional ADC maps increased 93% (P<0.01) compared with those of the controls. And global ADC strongly correlated with mean of regional ADC maps (r=0.96,P<0.001), suggesting global ADC may be a useful substitute for mean of regional ADC maps to investigate lung disease to save expensive 3He.

 
4003.   23 Quantitative Assessment of Compressed-Sensing Reconstruction Fidelity for 3D He-3 and H-1 Acquisitions in One Breath-hold
Kun Qing1, Talissa A. Altes2, Nicholas J. Tustison2, Jaime F. Mata2, G. Wilson Miller2, Eduard E. de Lange2, William A. Tobias3, Gordon D. Cates3, James R. Brookeman2, and John P. Mugler2
1Biomedical Engineering, University of Virginia, Charlottesville, VA, United States, 2Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, United States, 3Physics, University of Virginia, Charlottesville, VA, United States

 
The purpose of this work was to directly and quantitatively evaluate the reconstruction fidelity of undersampled compressed-sensing (CS) reconstructed 3D image sets by acquiring both the fully-sampled and undersampled acquisitions for a given nucleus (He-3 or H-1) in the same breath hold. Undersampled, CS-reconstructed H-1 3D images showed high similarity to their fully-sampled counterparts. While somewhat lower similarity indices were found for undersampled, CS-reconstructed He-3 3D image sets, this can be attributed to factors unrelated to the actual performance of the undersampled acquisition with CS reconstruction, including diaphragm movement, the non-equilibrium hyperpolarized magnetization, and B1 inhomogeneity.

 
4004.   24 Anatomical Distribution of Hyperpolarized 3He and 129Xe MRI Apparent Diffusion Coefficients in Asthma
Sarah Svenningsen1,2, Andrew Wheatley1, Miranda Kirby1,2, Adam Farag1, Alexei Ouriadov1, Giles Santyr1,2, David G McCormack3, and Grace Parraga1,2
1Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada, 2Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada, 3Department of Medicine, The University of Western Ontario, London, Ontario, Canada

 
The high cost and limited availability of helium-3 (3He) gas has restricted clinical translation of this structure-function pulmonary imaging method, necessitating a transition to xenon-129 (129Xe) gas for pulmonary imaging which provides distinct differences that must be explored. We compared 3He and 129Xe ADC anatomical differences from the anterior-to-posterior slices in five subjects with asthma. For 3He and 129Xe, the relationship between anatomical location and ADC was statistically significant. Although 129Xe atoms are heavier, have slower diffusion coefficients in air with the potential for less homogeneous mixing, anatomical ADC gradients are similar to 3He MRI which bodes well for translation.
 
Electronic Poster Session - Body

Contrast-Enhanced Liver MRI
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  16:00 - 17:00

  Computer #  
4005.   25 Effect of Pre-Contrast T1 on the Reproducibility of Liver Perfusion Parameters
Shimon Aronhime1, Claudia Calcagno1, Hadrien Arezki Dyvorne1, Philip Robson1, Henry Rusinek2, Maria Isabel Fiel3, Douglas Dieterich3, and Bachir Taouli1
1Radiology, Mount Sinai School of Medicine, New York, New York, United States, 2Radiology, New York University, New York, New York, United States,3Department of Medicine/Liver Disease, Mount Sinai School of Medicine, New York, New York, United States

 
Perfusion changes observed in liver fibrosis and cirrhosis can be quantified with perfusion-weighted MRI and a pharmacokinetic model. In this preliminary study, we have assessed the reproducibility of liver perfusion metrics using techniques aimed at optimizing the conversion of signal intensity to gadolinium concentration during 3D T1 perfusion—weighted MRI of the liver. All conversion techniques proved to have acceptable to poor reproducibility with no significant difference in reproducibility between the different conversion techniques. These early results indicate that reproducibility of liver perfusion parameters is not affected by the method of gadolinium concentration calculation.

 
4006.   26 High Frame Rate 3D Dynamic Contrast Enhanced Imaging of the Liver with Continuous Acquisition
Mahdi S Rahimi1, Kang Wang2, James H Holmes2, Jean H Brittain2, Scott B Reeder1,3, and Frank R Korosec3,4
1Biomedical Engineering, University of Wisconsin, Madison, WI, United States, 2Global Applied Science Laboratory, GE Healthcare, Madison, WI, United States, 3Radiology, University of Wisconsin, Madison, WI, United States, 4Medical Physics, University of Wisconsin, Madison, WI, United States

 
Dynamic Contrast Enhanced (DCE) liver perfusion imaging is a powerful tool for detection and assessment of liver lesions, including hepatocellular carcinoma (HCC). In this work, The IVD-HYCR method is improved by using fluoro-triggering and enabling continuous scanning during the passage of the contrast agent with retrospective identification of multiple breath-hold start times and durations, increasing the method’s ability to accurately and consistently acquire high frame-rate images with optimal contrast timing. Continuous scanning during multiple breath-holds and use of data sharing enables acquisition of high spatial and temporal resolution images and numerous time frames, permitting more complete assessment of contrast dynamics.

 
4007.   27 Improved Hepatic Arterial Phase MRI with 3 second Temporal Resolution
MUKTA Dilipkumar AGRAWAL1, Pascal Spincemaille1, Kevin W Mennitt1, Bo Xu2, Yi Wang1,2, and Martin R Prince1,3
1Radiology, Weill Cornell Medical Center, New York, NY, United States, 2Departments of Biomedical Engineering, Cornell University, New York, NY, United States, 3Radiology, Columbia University, New York, NY, United States

 
Purpose: To assess 3 second temporal resolution for arterial phase bolus timing on dynamic liver MRI. Methods: : 100 consecutive patients undergoing fluoro-triggered dynamic gadoxetate enhanced liver MRI with standard LAVA Cartesian k-space acquisition, were compared to 61 consecutive patients imaged using a spiral k-space trajectory LAVA reconstructed at 3second temporal resolution with sliding window reconstruction. Results: Spiral LAVA had superior bolus timing, hepatic artery branch order visualization and overall image quality scoring, compared to standard LAVA (p< 0.001). Conclusion: Dynamic liver MRI bolus timing improves using 3second temporal resolution.

 
4008.   28 Single breath-hold quadruple arterial phase dynamic MRI of the liver using LAVA FLEX sequence and 32 channel coil at 3T
Aaron Burns1, Ersin Bayram2, William Simpson1, and Bachir Taouli1
1Mount Sinai School of Medicine, New York, NY, United States, 2GE Healthcare, Waukesha, WI, United States

 
In this study, we have assessed the image quality and liver lesion conspicuity of a quadruple arterial phase acquisition on the liver obtained in a single breath-hold at 3T using a LAVA FLEX sequence with 32 channel torso coil enabling high parallel imaging capabilities. 42 patients were assessed. Image quality was considered to be good to excellent, and none of the patients had non diagnostic quality study. Artifacts were mostly related to parallel imaging ghosting. Hypervascular lesion conspicuity was best during the 2nd arterial phase.

 
4009.   29 Contrast-enhanced free-breathing perfusion weighted MR imaging of the whole-liver with high spatial and temporal resolution.
Hersh Chandarana1, Li Feng1, Tobias Kai Block1, Joseph P Stepancic1, Daniel K Sodickson1, and Ricardo Otazo1
1Radiology, NYU Langone Medical Center, New York, NY, United States

 
Studies have shown the utility of perfusion weighted MR imaging (PWI) in diagnosis of liver fibrosis, characterization of liver lesions, and for monitoring treatment response. However, for PWI to gain acceptance in clinical practice, acquisition schemes need to be robust to respiratory-motion, and should be able to acquire simultaneous high spatial and temporal resolution data with whole-liver coverage. As one approach for accelerated imaging is use of compressed-sensing (CS) reconstruction techniques, we propose the feasibility of performing free-breathing high spatial and temporal resolution imaging of the whole-liver with radial golden-angle sampling with combined compressed sensing and parallel imaging reconstruction.

 
4010.   30 Dynamic whole-liver imaging using a spiral acquisition technique: feasibility and initial results in assessment of liver fibrosis
Krishna Juluru1, Jonathan P Dyke1, Pascal Spincemaille1, Andrew H Talal2, and Rhonda Yantiss3
1Radiology, Weill Cornell Medical College, New York, NY, United States, 2Medicine, Weill Cornell Medical College, New York, NY, United States, 3Pathology, Weill Cornell Medical College, New York, NY, United States

 
The purpose of this study was to prospectively assess the feasibility of dynamic whole liver imaging using a spiral acquisition technique for the purpose of evaluation of liver fibrosis. The spiral technique allows whole liver imaging with high temporal resolution, while maintaining spatial resolution, and permitting sliding window reconstruction. Enhancement curves demonstrate differences in perfusion between subjects who are normal and who have biopsy-proven liver fibrosis.

 
4011.   31 Improved reconstruction of partial Fourier 3D dual-echo Dixon images
Gregory J Wilson1,2, Anne-Sophie Glantenay3, Holger Eggers4, Gwenael Herigault3, Thomas G Perkins1, John Penatzer1, and Jeffrey H Maki2
1Philips Healthcare, Cleveland, OH, United States, 2Radiology, University of Washington, Seattle, WA, United States, 3Philips Healthcare, Best, Netherlands,4Philips Research, Hamburg, Germany

 
Calculated in-phase and opposed-phase images can be produced from dual-echo Dixon imaging with flexible echo times. Potentially, this sequence could replace the standard in-phase and opposed-phase multi-slice FFE scan in a liver exam, shortening exam times. For adequate resolution, however, the 3D dual-echo Dixon scan must be acquired with partial Fourier during a breathhold. Partial Fourier acquisitions complicate Dixon reconstruction as phase information is compromised. This study evaluates a new partial Fourier reconstruction method that is compatible with analytical Dixon water-fat separation.

 
4012.   32 Arterial Enhancement Fraction in Liver Fibrosis and Cirrhosis
Hsin-You Ou1, Susanne Bonekamp1, David Bonekamp1, Celia P. Corona-Villalobos1, Vivek G. Halappa1, Li Pan2, Bernhard Geiger3, and Ihab Kamel1
1The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland, United States, 2Center for Applied Medical Imaging Siemens Corporate Research, Baltimore, Maryland, United States, 3Siemens Corporate Research, Princeton, NJ, United States

 
Fibrosis and cirrhosis are the consequences of chronic liver disease which are currently assessed by liver biopsy which is limited by its invasiveness, sampling error, and observer variability. Since fibrosis and cirrhosis lead to alterations in blood flow to the liver the evaluation of hemodynamic changes in the liver has been suggested as a noninvasive measure. This study found that the arterial enhancement fraction of the liver on tri-phasic MRI correlated with the degree of liver fibrosis and cirrhosis in 59 patients with chronic liver disease who underwent MRI and liver biopsy within 12 months.

 
4013.   33 Revisiting arterial enhancement of small (1-2 cm) hepatic nodules on dynamic MRI in patients at high risk for hepatocellular carcinoma
Chansik An1, Mi-Suk Park1, Woo-Suk Chung1, Yeo-Eun Kim1, Hyung-Jin Rhee1, and Myeong-Jin Kim1
1Diagnostic radiology, Yonsei University Health System, Seoul, Korea

 
Arterial enhancement of a hepatic nodule on dynamic magnetic resonance imaging is one of the major diagnostic criteria for hepatocellular carcinoma. In general, arterial enhancement has been accepted as showing "hyperintensity compared to the surrounding liver parenchyma on arterial phase¡±. In this study, however, we showed that arterial enhancement should be determined by comparing pre-contrast and arterial phase images rather than assessing arterial phase alone, and that subtraction imaging can play a critical role in determining arterial enhancement because it can more accurately demonstrate arterial enhancement than visual comparison of the two phases.

 
4014.   34 Dynamic Contrast Enhanced MR Liver Imaging using IVD HYCR: Initial Experience
Kang Wang1, Eric M. Bultman2, James H. Holmes1, Jean H. Brittain1, and Scott B. Reeder2,3
1Global Applied Science Laboratory, GE Healthcare, Madison, WI, United States, 2Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, United States, 3Radiology, University of Wisconsin-Madison, Madison, WI, United States

 
Dynamic contrast-enhanced (DCE) liver MRI is a powerful tool for the diagnosis and characterization of hepatocellular carcinoma (HCC). In this work, a previously developed technique called IVD HYCR is applied to DCE liver imaging to achieve volumetric liver coverage with 2.0 mm isotropic spatial resolution and 4.0 sec temporal resolution. Results from both healthy volunteers and patient volunteers with HCC are presented.

 
4015.   35 High spatio-temporal resolution contrast-enhanced MRI with view sharing improves detection of small hepatocellular carcinomas
Sharon Elizabeth Clarke1, Manojkumar Saranathan1, Dan Rettmann2, Brian Hargreaves1, and Shreyas Vasanawala1
1Radiology, Stanford University, Stanford, CA, United States, 2GE Healthcare, Global Applied Science Laboratory, Rochester, MN, United States

 
This study demonstrates that a new method of high temporal-spatial resolution dynamic contrast enhanced liver imaging improves detection of small hepatocellular carcinomas in patients undergoing surveillance for this disease.

 
4016.   36 Reticular T1 hypointensity at hepatocellular phase Gd-EOB-DTPA enhanced MR imaging: a non-invasive sign of oxaliplatin induced hepatic toxicity
Henry Tam1, Toni Wallace1, Erica Scurr1, David J Collins2, Ian Chau3, David Cunningham3, Martin O Leach4, and Dow-Mu Koh1
1Radiology, Royal Marsden Hospital, Sutton, Surrey, United Kingdom, 2CRUK and EPSRC, Sutton, Surrey, United Kingdom, 3Oncology, Royal Marsden Hospital, Sutton, Surrey, United Kingdom, 4Institute of Cancer Research, Sutton, Surrey, United Kingdom

 
We describe the prevalence and associated imaging findings in patients with colorectal hepatic metastases treated with chemotherapy who demonstrated reticular T1 hypointensity on the hepatocellular phase of Gd-EOB-DTPA enhanced MR imaging. This sign is only observed in patients treated with oxaliplatin based chemotherapy, and is associated with sinusoidal congestion or dilatation at histology. Reticular T1 hypointensity on the hepatocellular phase Gd-EOB-DTPA enhanced imaging appears to be a useful non-invasive sign for sinusoidal congestion resulting from oxaliplatin treatment toxicity in the liver.

 
4017.   37 HCC-to-liver contrast on arterial-dominant phase images of EOB-enhanced MRI: comparison with dynamic CT and CTHA
Naoki Kanata1, Takeshi Yoshikawa1, Yoshiharu Ohno1, Tomonori Kanda1, Koji Uchida2, Hisanobu Koyama1, Kazuhiro Kitajima1, Satoru Takahashi1, and Kazuro Sugimura1
1Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, 2Radiology, Shimane University Faculty of Medicine, Izumo, Shimane, Japan

 
Dynamic CT and CTHA are more suitable modalities than EOB-enhanced MRI for evaluation of arterial blood supply in HCC. This should be taken into account for diagnosis and management of HCC.

 
4018.   38 Gd-EOB-DTPA in patients with primary sclerosing cholangitis (PSC) – An analysis of the hepatobiliary excretion kinetic
Kristina Imeen Ringe1, Elmar Merkle2, Jan Hinrichs1, Frank Wacker1, and Bernhard Meyer1
1Department of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Niedersachsen, Germany, 2Department of Radiology, Duke University Medical Center, United States

 
The purpose of this study was to analyze the hepatobiliary excretion of Gd-EOB-DTPA into different segments of the hepatobiliary system in 111 patients with primary sclerosing cholangitis (PSC) and to work out a possible correlation with severity of disease. The results of our study show, that hepatobiliary excretion in patients with PSC is significantly delayed compared to patients with normal liver function, and further dependent on bilirubin level, necessitating eventual adjustments of the MR imaging protocol.

 
4019.   39 Accuracy of Gadoxetic Acid-Enhanced Magnetic Resonance Imaging for the Diagnosis of Sinusoidal Obstruction Syndrome in Patients with Chemotherapy-Treated Colorectal Liver Metastases
Na-Young Shin1, Myeong-Jin Kim1, Joon Seok Lim1, Mi-Suk Park1, Yong-Eun Chung1, Jin-Young Choi1, Ki Whang Kim1, and Young-Nyun Park1
1Yonsei University Severance Hospital, Seoul, Korea

 
To assess whether hepatobiliary phase images of gadoxetic acid-enhanced magnetic resonance imaging (EOB-MRI) is a diagnostic finding of sinusoidal obstruction syndrome (SOS) in patients with hepatic metastases who have undergone chemotherapy, we retrospectively analysed EOB-MRI of 42 patients who had undergone chemotherapy before hepatic resection of colorectal hepatic metastases using a 5-point scale. Reticular hypointensity on hepatobiliary phase images of EOB-MRI is highly specific for the diagnosis of SOS in patients with treated colorectal hepatic metastases with good interobserver agreement.

 
4020.   40 Morphine enhanced 3D T1 Gadoxetate MRCP for pre-transplant living related liver donor evaluation
MUKTA Dilipkumar AGRAWAL1, Kevin W Mennitt1, Honglei Zhang1, Benjamin Samstein2, Jean C Emond2, Tomoaki Kato2, and Martin R Prince1,3
1Radiology, Weill Cornell Medical Center, New York, NY, United States, 2Liver transplantation surgery, Columbia University, New York, NY, United States,3Radiology, Columbia University, New York, NY, United States

 
PURPOSE: To assess low dose morphine for improved visualization of intrahepatic bile ducts on T1 magnetic resonance cholangiography (MRC), in potential liver donors. MATERIALS AND METHODS: 60 consecutive potential liver donors were assessed without (n=30) or with (n=30) intravenous morphine for Intra hepatic biliary branch order visualization, CBD diameter and overall image quality. RESULTS: At 45 and 60 minutes post morphine, mean intra hepatic bile duct branch order visualization, CBD diameter and over all image quality scores were greater compared to without morphine (p< 0.05). CONCLUSION: Intravenous low dose morphine distends and improves visualization of bile ducts on T1 MRC.

 
4021.   41 Differentiation of Hepatic Adenoma versus Focal Nodular Hyperplasia using Gadoxetic Acid
Kiyarash Mohajer1,2, Jessica Robbins1, Agnes Loeffler3, Richard Bruce1, and Scott Reeder1
1Radiology, University of Wisconsin, Madison, WI, United States, 2Radiology, UCLA, Los Angeles, CA, United States, 3Pathology, University of Wisconsin, Madison, WI

 
differentiation of hepatic adenoma (HA) and focal nodular hyperplasia (FNH) is important because HA’s are often resected due to risk of hemorrhage and risk of malignant degeneration, while FNH’s require no intervention. Characterization of HA vs. FNH with extracellular gadolinium-based contrast-agents is challenging because imaging characteristics during dynamic contrast imaging can be similar. The recent FDA approval of a new hepatobiliary agent (gadoxetic acid) offers new opportunities to characterize HA and FNH. However, there are very few reported cases with pathological-imaging correlation. In this work, we report the imaging characteristics of 6 histologically proven HA and 34 FNH lesions.

 
4022.   42 Ultra-high-field imaging of the biliary tract at 7 Tesla: initial results of Gd-EOB-DTPA-enhanced MRCP
Anja Fischer1,2, Oliver Kraff1,2, Stephan Orzada1,2, Lena C. Schäfer1,2, Mark E. Ladd1,2, Lale Umutlu1,2, and Thomas C. Lauenstein1
1Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen, Germany, 2Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, Essen, Germany

 
MR imaging of the liver was investigated at 7 Tesla using Gadoxetic acid for depiction of the intra- and extrahepatic biliary tract. A custom-built eight-channel RF transmit/receive body coil and RF shimming were used. In 10 healthy volunteers, dynamic T1-weighted 3D VIBE and 3D FLASH inversion recovery sequences were acquired in the hepatobiliary phase. For comparison, all volunteers underwent a conventional T2-weighted MRCP at 3T. Initial results demonstrate feasibility, showing both benefits and limitations of this technique.

 
4023.   43 Peripheral Low Intensity Sign in Hepatic Hemangioma: Diagnostic Pitfall in Hepatobiliary Phase of Gd-EOB-DTPA Enhanced MR Imaging of the Liver
Tsutomu Tamada1, Atsushi Higaki1, Tomohiro Sato1, Akihiko Kanki1, Hiroki Higashi1, Akira Yamamoto1, and Katsuyoshi Ito1
1Radiology, Kawasaki Medical School, Kurashiki City, Okayama, Japan

 
The gperipheral washout signh in the late phase of dynamic contrast-enhanced MR imaging (DCE-MRI) using purely extracellular Gd chelates has been considered as a specific sign of malignant hepatic tumors such as hepatic metastases. We compared the frequency of the presence of gperipheral low intensity signh between the hepatic hemangiomas and the hepatic metastases on the hepatobiliary phase of DCE-MRI obtained with Gd-EOB-DTPA. As the results, radiologists should recognize that peripheral low intensity sign is not specific for malignant tumors such as liver metastases, and can be seen even in hepatic hemangiomas on hepatobiliary phase of Gd-EOB-DTPA enhanced MR imaging.

 
4024.   44 EOB-Enhanced Liver MRI: Parameter Optimizations of Post-Contrast T2- and Diffusion-Weighted Imaging.
Takeshi Yoshikawa1, Nobukazu Aoyama2, Yoshiharu Ohno1, Akira Suwa3, Katsusuke Kyotani2, Tomonori Kanda1, Naoki Kanata1, Hisanobu Koyama1, Kazuhiro Kitajima1, Satoru Takahashi1, Hideaki Kawamitsu2, and Kazuro Sugimura1
1Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, 2Division of Radiology, Kobe University Hospital, Kobe, Hyogo, Japan, 3Philips Electronics Japan, Tokyo, Japan

 
We optimized imaging parameters of Gd-EOB-DTPA-enhanced T2WI and DWI sequences in phantom and clinical studies for time-saving liver MRI.On post-contrast T2WI and DWI images, signal intensities and ADC values are severely affected by EOB concentration unless imaging parameters are carefully chosen. Post-contrast T2WI and DWI should be carefully applied especially to rare conditions.

 
4025.   45 Quantification of the hepatobiliary uptake of Gd-EOB-DTPA can separate advanced from mild fibrosis
Bengt Norén1,2, Mikael Fredrik Forsgren2,3, Olof Dahlqvist Leinhard2,3, Nils Dahlström1,2, Johan Kihlberg1,2, Thobias Romu2,4, Stergios Kechagias5,6, Sven Almer6,7, Örjan Smedby1,2, and Peter Lundberg2,3
1Depts of Medical and Health Sciences (IMH), Division of Radiological Sciences, Linköping University, Linköping, Sweden, 2Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden, 3Depts of Radiation Physics, Linköping University and Radiation Physics, UHL County Council of Ostergotland, Linköping, Sweden, 4Depts of Biomedical Engineering (IMT), Linköping University, Linköping, Sweden, 5Depts of Medical and Health Sciences (IMH), Division of Cardiovascular Medicine, Linköping University, Linköping, Sweden, 6Depts of Endocrinology and Gastroenterology, UHL County Council of Ostergotland, Linköping, Sweden, 7Depts of Clinical and Experimental Medicine (IKE), Divison of Gastroenterology and Hepatology, Linköping University, Linköping, Sweden

 
The purpose of this prospective study was to quantitatively measure the hepatocyte-specific uptake of Gd-EOB-DTPA using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and compare it with histopathological grading of fibrosis. The biopsy scores were grouped into no/mild fibrosis (F0-2, n=27) and advanced fibrosis (F3-4, n=11). Applying a new quantification procedure for calculation of the hepatocyte specific contrast uptake, this study can confirm that impaired hepatobiliary function severely influences the hepatocyte-specific uptake of Gd-EOB-DTPA and shows promising results for a non-invasive approach to separate mild liver fibrosis from advanced, something pure SI-based contrast ratios may fail to distinguish.

 
4026.   46 Clinicopathological significance of the peritumoral decreased uptake area of Gd-EOB-DTPA in hypervascular hepatocellular carcinoma: Novel application of Gd-EOB-DTPA-enhanced MRI
Akihiro Nishie1, Yoshiki Asayama1, Kousei Ishigami1, Daisuke Kakihara1, Tomohiro Nakayama1, Yasuhiro Ushijima1, Yukihisa Takayama1, Ken Shirabe1, Nobuhiro Fujita1, masakazu Hirakawa1, and Hiroshi Honda1
1Kyushu University, Fukuoka, Fukuoka, Japan

 
For the first time we focused on the peritumoral decreased uptake area of Gd-EOB-DTPA (PDUAE) in HCC and investigated the significance of this “pseudolesion” by comparing variable clinical and pathological factors. As a result, PDUAE was associated with vascular invasion. When the presence of PDUAE was used as an indicator of vascular invasion, relatively high diagnostic performance was obtained. In addition, the vascular invasion of our enrolled cases was “microscopic”. In general, it remains difficult to detect “microscopic” vascular invasion on dynamic CT or MRI. Our results suggested that “microscopic” vascular invasion could be predicted with Gd-EOB-DTPA-enhanced MRI with ease.

 
4027.   47 Post-EOB-enhanced T2WI, DWI, and Balanced FFE: Comparison of 1.5T and 3T Scanners using Diluted EOB Phantoms
Takeshi Yoshikawa1, Nobukazu Aoyama2, Yoshiharu Ohno1, Akira Suwa3, Katsusuke Kyotani2, Tomonori Kanda1, Naoki Kanata1, Hisanobu Koyama1, Kazuhiro Kitajima1, Satoru Takahashi1, Hideaki Kawamitsu2, and Kazuro Sugimura1
1Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, 2Division of Radiology, Kobe University Hospital, Kobe, Hyogo, Japan, 3Philips Electronics Japan, Tokyo, Japan

 
The effects of EOB on T2WI, DWI, and balanced FFE were assessed at both 1.5 T and 3T scanners to optimize imaging parameters in EOB-enhanced liver MRI. SNR in the images and ADC values were severely affected by EOB concentration. The filed-strength of scanner affected patterns of neither SNR nor ADC changes. Imaging parameters should be carefully chosen for EOB-enhanced T2WI, DWI, and balanced FFE.

 
4028.   48 MR imaging characterization and staging of malignant central bile duct stenosis: added value of the hepatocyte specific contrast agent gadoxetate disodium
Kristina Imeen Ringe1, Hueseyin Bektas2, Bastian Ringe2, Patrick Opherk1, Angela Reichelt1, Joachim Lotz3, Frank Wacker1, and Bernhard Meyer1
1Department of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Niedersachsen, Germany, 2Department of General-, Visceral- and Transplantation Surgery, Hannover Medical School, Hannover, 3Department of Diagnostic Radiology, University Hospital Göttingen, Göttingen

 
The purpose of this prospective study was to assess the added value of the hepatocyte specific contrast agent gadoxetate disodium for characterization and staging of tumors in patients with malignant central bile duct stenosis. Intraoperative findings were used as gold standard. The results of our study show, that the application of gadoxetate disodium improves assessment of tumor extension, which is necessary to define tumor resectability. In this context images acquired in the late hepatocyte phase proved most useful for exact tumor delineation.
 
Electronic Poster Session - Body

Diffuse Liver Disease
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  17:00 - 18:00

  Computer #  
4029.   
25 Feeding with large amounts of fructose or glucose increases hepatic lipid content only when positive energy balance is achieved
Mary Charlotte Stephenson1, Richard D Johnston2, Eleanor F Cox1, Elisa Placidi1, Guruprasad P Aithal2, Ian A MacDonald3, and Peter G Morris1
1SPMMRC, School of Physics and Astronomy, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, 2Nottingham Digestive Diseases Centre, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, 3School of Biomedical Sciences, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom

 
Fructose has been linked to rises in obesity and liver disease. This study observes the effects of an isoenergetic diet containing excess fructose or glucose on hepatic and muscle lipid stores, and 31P metabolite levels, and compares these with a hyperenergetic diet with equivalent excess fructose or glucose. We show that 2 weeks of a high fructose isoenergetic diet does not increase lipid deposition. Increasing energy intake leads to increased levels of hepatic lipid and inorganic phosphate. However, these changes occur following hyperenergetic fructose and glucose diets, indicating that the effects are more likely the result of energy overfeeding.

 
4030.   
26 Molecular Imaging of Non-Alcoholic Fatty Liver Disease using an Endogenous Hyperpolarized Redox Sensor
Kayvan R. Keshari1, Andrew Taylor1, Zhen Jane Wang1, John Kurhanewicz1, Daniel B. Vigneron1, and David M. Wilson1
1Radiology and Biomedical Imaging, University of California, San Francisco (UCSF), San Francisco, CA, United States

 
Non-alcoholic fatty liver disease (NAFLD) is recognized as the most prevalent liver abnormality in the United States. Although changes in redox have been implicated in the onset and progression of NAFLD, methods to image this disease are limited. In recent work, hyperpolarized [1-13C] dehydroascorbate (DHA), which is rapidly converted to Vitamin C in vivo, has been identified as an endogenous redox sensor for non-invasive MR imaging. In this study, we demonstrate the use of HP [1-13C] DHA to image redox changes in a standard model of NAFLD and correlate these findings with standard 1H imaging and histopathology.

 
4031.   
27 A Comparison of MRI and Dual-Energy CT (DECT) for Quantification of Hepatic Steatosis in the ob/ob Mouse
Nathan S Artz1, Catherine DG Hines2, Jens-Peter Kuhn1, Alejandro Roldan-Alzate1, Rashmi Agni3, Steven Brunner4, Guang-Hong Chen4, and Scott B Reeder1,4
1Department of Radiology, University of Wisconsin, Madison, WI, United States, 2Pharmaceuticals, Merck & Co., Inc, Philadelphia, PA, United States,3Department of Surgical Pathology, University of Wisconsin, Madison, WI, United States, 4Department of Medical Physics, University of Wisconsin, Madison, WI, United States

 
Quantitative MRI methods have shown great promise as non-invasive biomarkers of hepatic steatosis, with validation studies performed in phantoms, animal models, and patients. However, CT and increasingly Dual-Energy CT (DECT), is used for most advanced imaging studies of the abdomen. The purpose of this study was to compare MRI and DECT for fat quantification using tissue triglyceride (TG) concentration as the reference, in an ob/ob mouse model. Excellent correlation (r >= 0.93,p<0.001) was observed for both CT attenuation (HU) and MRI fat-fraction compared with tissue TG and each other. Other DECT measurements demonstrated good, but inferior, correlation with TG and MRI.

 
4032.   28 Fast 3D Quantification of Fat Liver Tissue Using Sequentially Shifted echo times and a singular value decomposition matrix pencil method
Xeni Deligianni1, Klaus Scheffler2,3, and Oliver Bieri1
1Division of Radiological Physics - Department of Radiology and Nuclear Medicine, University of Basel Hospital, Basel, Switzerland, 2MTC Department, MPI for Biological Cybernetics, Tübingen, Germany, 3Dept. Neuroimaging and MR-Physics, University of Tübingen, Tübingen, Germany

 
Assessing the fat liver properties is of increased clinical interest, such as for quantifying non-alcoholic fatty liver disease. MR imaging of liver fat has been proven to be a valuable non-invasive alternative to biopsy. A 3D multi-echo gradient echo sequence with sequentially shifted echo times is proposed for whole liver fat tissue characterization within a single breath-hold. The signal time course is analyzed using a voxel-wise singular value decomposition to yield water-fat fractions and corresponding T2* relaxation times. This approach provides a robust way for fast and reliable analysis of water and fat signals.

 
4033.   29 Fat Quantification in Liver with 3D Multi-Echo GRE Dixon in a Single Breath-Hold: Comparison with HISTO and 2D Multi-Echo GRE Dixon
Xiaodong Zhong1, Puneet Sharma2, Wesley D Gilson3, Vladimir Jellus4, Stephan Kannengiesser4, Brian M Dale5, Berthold Kiefer4, and Diego R Martin2
1MR R&D Collaborations, Siemens Healthcare, Atlanta, GA, United States, 2Radiology Department, University of Arizona, Tucson, AZ, United States,3Corporate Research, Siemens Corporation, Baltimore, MD, United States, 4Siemens AG Healthcare Sector, Erlangen, Germany, 5MR R&D Collaborations, Siemens Healthcare, Cary, NC, United States

 
In this study, a single breath-hold multi-echo 3D GRE Dixon method with whole liver coverage and high slice resolution was developed and preliminary evaluation was performed in clinical patients. This 3D GRE Dixon method produced similar liver fat quantification results to those measured with 2D multi-echo GRE Dixon, and high-speed T2-corrected multiple-echo 1H-MRS (HISTO) as a reference standard, for the protocols and patients tested in this study. This single breath-hold 3D GRE Dixon method may be adopted in the routine clinical scan and have great potential for evaluating the hepatic steatosis for obesity related liver diseases.

 
4034.   30 Effect of Hepatocyte-Specific Gadolinium-Based Contrast Agents on Hepatic Fat-Fraction and R2*
Shane A Wells1, Diego Hernando1, Karl K Vigen1, and Scott B Reeder1,2
1Department of Radiology, University of Wisconsin-Madison, Madison, WI, United States, 2Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, United States

 
Chemical-shift based water-fat separation methods with R2*-correction can accurately quantify fat-fraction and R2*, as surrogate biomarkers of hepatic steatosis and iron overload. New hepatobiliary contrast agents dramatically alter the T1 and R2* of liver and may impact quantification of fat and iron. In this work, we investigate the impact of a hepatocyte-specific contrast agent (gadoxetic acid) on fat-fraction and R2*. We demonstrate that fat-fraction is unaffected by gadoxetic acid, so long as low flip angles are used. However, gadoxetic acid increases the apparent R2* demonstrating that quantification of iron overload should always be performed prior to contrast administration.

 
4035.   31 T1, T2 and T2* relaxation time measurements in the liver: Reproducibility, inter- and intra-observer variability
Caroline L Hoad1, Naaventhan Palaniyappan2, Carolyn Costigan1, Eleanor F Cox1, Luca Marciani2, Philip Kaye3, Neil Guha2, Robin C Spiller2, Penelope A Gowland1, Guruprasad P Aithal2, and Susan T Francis1
1Physics and Astronomy, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, 2Nottingham Digestive Diseases Centre, NIHR Biomedical Research Unit, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom, 3Department of Cellular Pathology, Nottingham University Hospitals NHS Trust, Derby Royal Hospital, Derby, United Kingdom

 
Reproducibility of whole liver relaxation time measurements using respiratory triggered echo-planar imaging was carried out on 8 healthy volunteers, scanned on 2 separate occasions. Modal T1, T2 and T2* parameters were obtained from fitting a Gaussian curve to the histograms of the fitted data. The coefficient of variance (CV) was 1.5 %, 3.1 % and 4.3 % for T1, T2 and T2* respectively. Inter- and Intra-observer variability was assessed using relaxation time data sets from 20 chronic liver disease patients. Inter- and intra-observer CVs were below 1% suggesting that biological variability and scanner related noise dominated the CVs of the reproducibility data.

 
4036.   32 MR-liver fat volume fraction quantification using a magnitude-based technique with independent fat and water T2* estimations, T1-related bias correction and accounting for fat multiple resonances
Benjamin Leporq1, Helene Ratiney1, Herve Saint-Jalmes2,3, Frank Pilleul1,4, and Olivier Beuf1
1CREATIS; CNRS UMR 5220; INSERM U1044; INSA-Lyon; UCBL Lyon 1, Villeurbanne, Rhône-Alpes, France, 2LTSI; Inserm U642; Université Rennes 1, Rennes, Bretagne, 3CRLCC; Centre Eugène Marquis, Rennes, Bretagne, France, 4Hospices civils de Lyon; CHU Edouard Herriot, Lyon, Rhône-Alpes, France
 
In Western countries, Non-Alcoholic Fatty Liver Disease (NAFLD) is the most common cause of chronic liver diseases. Because NAFLD can evolve into Non-Alcoholic Steato-Hepatitis and may lead to liver fibrosis up to cirrhosis, a clinical follow-up of NAFLD would be valuable. This work presents a MR magnitude-based technique for liver fat volume fraction quantification with independent fat and water T2* estimations, T1-related bias and spectral complexity of fat corrections using a two-angles multiple gradient-echo acquisition. The method described was applied in-vivo at 1.5T in a prospective study and at 3.0T on healthy subjects. It was additionally compared with 1H MRS on fat-water phantoms.

 
4037.   
33 Liver Fat Quantification with MRI: Comparison of 2 point-Dixon and 3 point-Dixon methods to T2 corrected multiecho single-voxel spectroscopy
Janakan Satkunasingham1, Ami Shah2, Stephan Kannengiesser3, Andre De Oliveira3, Marcello Facciuto2, and Bachir Taouli2
1Queen’s University, Kingston, Ontario, Canada, 2Mount Sinai School of Medicine, New York, NY, United States, 3Siemens Healthcare, Erlangen, Germany

 
In this study involving a large number of patients (n=211), we have compared the diagnostic accuracy of 2 point Dixon and 3 point Dixon sequences to T2-corrected multiecho MR spectroscopy used as the reference standard. Hepatic iron deposition was determined using a breath-hold multi-echo T2* sequence. Results demonstrated the superiority of the 3 point Dixon over the 2 point Dixon method for quantifying hepatic fat, mainly related to the presence of concomitant iron deposition.

 
4038.   34 Liver Iron Content Quantification via Single Breath-Hold MR Imaging at 3.0 Tesla
Michel Louis Lauzon1,2, Farzana Sayani3, Karen Valentine3, Richard Frayne1,2, and Houman Mahallati1,2
1Radiology, University of Calgary, Calgary, AB, Canada, 2Seaman Family MR Research Centre, Calgary, AB, Canada, 3Medicine, University of Calgary, Calgary, AB, Canada

 
The current gold standard for quantification of liver iron content (LIC) in iron-overloaded states is liver biopsy, an invasive and potentially risky procedure. Safe non-invasive MR-based methods of measuring LIC are promising alternatives. Here, we quantify LIC using a multi-echo single breath-hold T2*-weighted spoiled gradient-recalled echo sequence at 3.0 T, and compare the results to biopsy. The mean MR-derived LIC estimates were similar to biopsy (to within 2.5 mg of iron per gram of dry liver weight), and MR covered a much larger liver extent than biopsy, had a stringent confidence interval, and was well tolerated by patients.

 
4039.   35 A Systematic Technique for Echo Truncation in MRI-Based R2* Calculations for Liver Iron Quantification Which Reduces Systematic and Random Error
Mustafa Rifaat Bashir1, Brian M Dale2, and Elmar Max Merkle1
1Radiology, Duke University Medical Center, Durham, NC, United States, 2Siemens Medical Solutions, Cary, NC, United States

 
Multi-echo gradient echo based MRI techniques have emerged as a useful clinical tool for estimating hepatic iron concentration by measuring liver R2*. Systematic and random errors can occur in the R2* solution based on the number of echoes used for the calculation. We explore the propagation of these errors, and propose and analyze a technique for reducing error by selecting an optimized number of echoes for the calculation. We compare this with standard techniques using Monte Carlo simulations and patient data.

 
4040.   36 Fat- and susceptibility-corrected R2* mapping for liver iron quantification: preliminary evaluation in a healthy cohort
Diego Hernando1, Jens-Peter Kühn1,2, and Scott B Reeder1,3
1Department of Radiology, University of Wisconsin-Madison, Madison, WI, United States, 2Department of Diagnostic Radiology, University Greifswald, Greifswald, MV, Germany, 3Department of Medical Physics, University of Wisconsin-Madison, Madison, WI, United States

 
R2*-MRI can be used to assess body iron deposition for diagnosis, staging and treatment monitoring of iron overload. However, the apparent R2* is often confounded by the presence of fat, noise floor and susceptibility effects (e.g., near tissue/air interfaces). Recently, a method was introduced to perform fat-corrected, complex-fitting, and susceptibility-corrected R2* mapping. In this work, we quantitatively evaluate the susceptibility correction in a cohort of 35 healthy subjects without iron overload. Uncorrected measurements showed significant deviations in R2*. These deviations were largely corrected by susceptibility-corrected R2*. This technique may be important for the assessment of iron deposition in the liver.

 
4041.   37 Noninvasive Assessment of Hepatic Stiffness in Nonalcoholic Fatty Liver Disease Using Magnetic Resonance Elastography at Multiple Frequencies
An Tang1,2, Lucas Shanholtzer2, Nikolaus Szeverenyi2, Rohit Loomba3, Michael Peterson4, Tanya Wolfson5, Anthony C. Gamst5, Richard L. Ehman6, and Claude B Sirlin2
1Radiology, University of Montreal, Montreal, Qc, Canada, 2Radiology, University of California, San Diego, San Diego, California, United States, 3Division of Gastroenterology, Hepatology, and Medicine, University of California, San Diego, San Diego, California, United States, 4Department of Pathology, University of California, San Diego, San Diego, California, United States, 5Biostatistics, University of California, San Diego, San Diego, California, United States, 6Radiology, Mayo Clinic, Rochester, Minnesota, United States

 
Liver stiffness was measured by magnetic resonance elastography (MRE) and compared with histology. MRE performed at 3.0 T with 1 axis and 3 axes motion sensitization at multiple frequencies showed strong correlations with fibrosis stage and a trend toward higher stiffness with increasing lobular inflammation grades in adults with NAFLD. These results confirm that MRE is useful for noninvasive assessment of fibrosis not only in a variety of chronic liver disease but also in a population of NAFLD patients.

 
4042.   
38 MRI-based detection of extracellular changes in the hepatic sinusoid in a rat model of non-alcoholic steatohepatitis
Scott Charles Beeman1, Joseph F Georges2, Lawrence Mandarino3,4, Jorge Rakela5, and Kevin M Bennett1
1Bioengineering, Arizona State University, Tempe, Arizona, United States, 2School of Life Sciences, Arizona State University, Tempe, Arizona, United States, 3School of Life Sciences, Arizona State University, Tempe, AZ, United States, 4Department of Medicine, Mayo Clinic in Arizona, Scottsdale, AZ, United States, 5Department of Gastroenterology and Hepatology, Mayo Clinic in Arizona, Scottsdale, AZ, United States

 
The goal of this work was to develop an MRI-based technique for detection of changes to the ECM of the hepatic sinusoid during chronic liver disease. Using cationic ferritin (CF), an ECM-targeted nanoparticle contrast agent, we show that T2* measurements in healthy animals decrease 50% after injection of CF while rats with chronic liver disease show no change in T2* after CF injection. This is likely due to the structural changes to the ECM that occur during chronic liver disease. These results suggest that MRI and CF may be used to detect ECM-specific changes in chronic liver diseases.

 
4043.   
39 Clinical Comparison of Single-R2* and Dual-R2* Correction for Accurate Fat Quantification in the Liver
Debra E. Horng1,2, Diego Hernando1, Catherine D.G. Hines3, and Scott B. Reeder1,2
1Radiology, University of Wisconsin-Madison, Madison, WI, United States, 2Medical Physics, University of Wisconsin-Madison, Madison, WI, United States, 3Merck Research Laboratories, West Point, PA, United States

 
We compared the performance of fat-fraction quantification using chemical shift encoded MRI using single-R2* and dual-R2* correction methods, using MR spectroscopy (MRS) as the reference standard. From a group of 97 patients, 20 patients with fat fraction > 10% were identified, and chemical shift encoded fat-water imaging was performed. Fat-fraction was measured from the imaging data using both single-R2* and dual-R2* correction. Fat-fraction estimates were compared to co-registered spectroscopy measurements: single-R2* correction demonstrated higher agreement. Single-R2* modeling is more accurate than dual-R2* modeling for hepatic fat quantification in patients, even in those with high hepatic fat concentrations.

 
4044.   40 MR Imaging the Hepatic Manifestations and Complications of Hereditary Hemorrhagic Telangiectasia: A Pictorial Review
Christina Marie Chingkoe1, Errol Colak1, Vikram Prabhudesai1, Marie Faughnan2, and Anish Kirpalani1
1Department of Medical Imaging, St. Michael's Hospital, Toronto, Ontario, Canada, 2Division of Respirology and Director of HHT Program, St. Michael's Hospital, Toronto, Ontario, Canada

 
Hereditary hemorrhagic telangiectasia (HHT), an autosomal dominant disorder of variable penetrance, is characterized by the presence of mucocutaneous and visceral vascular malformations (VMs). Hepatic involvement occurs in 40% of patients with HHT. We perform liver MRI routinely in HHT patients to document hepatic VMs and to evaluate for hepatic complications of HHT. In this presentation, the MRI features of the hepatic manifestations of HHT are reviewed. These include intrahepatic shunting (arterioportal, arteriosystemic and portosystemic), discrete VMs (capillary telangiectasia, confluent vascular masses, arteriovenous malformations), focal nodular hyperplasia, sclerosing cholangitis from ischemic biliopathy, and potential complications (including hemosiderosis, cholangitis, intrahepatic abscess).

 
4045.   41 Vessel-penetrating sign in the liver: MR imaging manifestations of various liver pathologies
Kenji Matsuzaki1, Mayumi Takeuchi1, and Masafumi Harada1
1Department of Radiology, University of Tokushima, Tokushima, Tokushima, Japan

 
Preserved intrahepatic vessels may be observed within various benign and malignant pathologies in the liver as "vessel-penetrating sign" (VPS) on imaging. MRI has an advantage to demonstrate vessels without the administration of contrast medium as flow voids on spin echo sequences with long TR; echo planar diffusion-weighted imaging, or as high signal intensity structures on gradient echo sequences with steady state free precession. The presence of VPS suggests infiltrative tumor growth, highly non-destructive tumors, mass formed by the aggregated malignant tumors, or benign tumor-like conditions. We present diagnostic imaging features of various liver lesions, which show VPS, with pathologic correlation.

 
4046.   42 Voxel-wise reproducibility of Magnetic Resonance Rheology of the liver at 3T MRI
Anneloes E. Bohte1, Aart J. Nederveen1, Paul F.C. Groot1, Annikki de Niet2, Peter L.M. Jansen2, Ralph Sinkus3, and Jaap Stoker1
1Radiology, Academic Medical Center, Amsterdam, Netherlands, 2Gastroenterology, Academic Medical Center, Amsterdam, Netherlands, 3Radiology, Hôpital Beaujon, Paris, France

 
Liver fibrosis can be detected by means of Magnetic Resonance Rheology (MRR, also known as MR elastography). It has the potential to replace liver biopsy in patients with chronic liver disease. If this measurement becomes part of the clinical routine, one needs to know which changes in liver elasticity and viscosity over time can be accurately measured. In this study we define a threshold for detecting a significant change in both liver elasticity and viscosity in repeated MRR measurements in a group of 27 subjects containing both healthy volunteers and patients with viral hepatitis B/C.

 
4047.   43 Magnetic Resonance Elastography of Liver for Evaluation of Liver Fibrosis in Chronic Viral Hepatitis B and C in Asians: Experience From Two Tertiary Care Centres.
Sudhakar Kundapur Venkatesh1, Utaroh Motosugi2, Gang Wang1, Tamoaki Ichikawa2, Tsutomo Araki2, Seng Gee Lim3, and Aileen Wee4
1Diagnostic Imaging, National University Health System, Singapore, Singapore, Singapore, 2Radiology, University of Yamanashi, Yamanashi, Japan,3Gastroenterology and Hepatology, National University Health System, Singapore, Singapore, 4Pathology, National University Health System, Singapore, Singapore, Singapore

 
Chronic liver diseases lead to fibrosis and cirrhosis. The degrees of fibrosis and distribution pattern are different in chronic liver diseases from varied etiologies. MR Elastography is an accurate technique for quantification of liver stiffness which correlates with stages of fibrosis. We evaluated liver stiffness in histology proven cases of chronic hepatitis B and chronic hepatitis C from two leading centres in Asia. Our preliminary results show no significant differences in stiffness values in the livers of different stages of fibrosis from the two etiologies. The cut-off values for diagnosing significant fibrosis also did not show any significant difference.

 
4048.   44 Feasibility Study of Assessing Progression of Chronic Liver Disease with MR Elastography in an In Vivo Animal Model
Meng Yin1, Kevin J Glaser1, Jason L Bakeberg2, Christopher J Ward2, Peter C Harris2, and Richard L Ehman1
1Radiology, Mayo Clinic, Rochester, MN, United States, 2Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States

 
A feasibility study was performed for measuring hepatic shear stiffness in small animals to identify whether a selected animal model merits further study to see if hepatic stiffness correlates with hepatic inflammation and fibrosis progression. The results of this preliminary study demonstrated that increased liver stiffness is an early marker of disease progress in a Pkhd1 mouse model. If these results can be further confirmed with more sophisticated mechanical models to separate fluid-related inflammation and matrix-related fibrosis effects, MRE may provide means to distinguish hepatic inflammation before the onset of hepatic fibrosis.

 
4049.   45 Use of MRE Elastography in a Community Practice: Correlation of MRE Measurements of Liver Stiffness and Results of Liver Biopsy
Russell N. Low1,2, and Tarek Hassanein3
1Sharp and Children's MRI Center, San Diego, California, United States, 2San Diego Imaging, San Diego, CA, United States, 3Liver Centers of Southern California, Coronado, CA, United States

 
MR Elastography (MRE) noninvasively assesses liver stiffness and can rapidly provide information about the stage of liver fibrosis. Our comparisons of the results of MRE with liver biopsy show excellent correlation that validates its routine use for liver imaging in our practice.

 
4050.   46 Portal Perfusion Assessment in the Liver with Portal Spin Labeling at 3 Tesla MRI
Takeshi Yoshikawa1, Nobukazu Aoyama2, Yoshiharu Ohno1, Akira Suwa3, Katsusuke Kyotani2, Tomonori Kanda1, Naoki Kanata1, Hisanobu Koyama1, Kazuhiro Kitajima1, Satoru Takahashi1, Hideaki Kawamitsu2, and Kazuro Sugimura1
1Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan, 2Division of Radiology, Kobe University Hospital, Kobe, Hyogo, Japan,3Philips Electronics Japan, Tokyo, Japan

 
We developed portal spin labeling technique for evaluation of portal perfusion in the liver and liver tumors and report the initial results in clinical cases.

 
4051.   47 Quantification of altered hepatic blood flow with 4D velocity mapping during a meal challenge provocation
Alejandro Roldán-Alzate1, Eric Niespodzany1, Alex P Frydrychowicz1, Benjamin R Landgraf1, Oliver Wieben1,2, and Scott B Reeder1,2
1Radiology, University of Wisconsin, Madison, Wisconsin, United States, 2Medical Physics, University of Wisconsin

 
In addition to co-registered vascular anatomy, functional information, and analysis of flow patterns, 4D velocity mapping can be used to quantify blood flow. Using time resolved PC-MRI with 3D radial undersampling (PC-VIPR), a large data volume can be assessed. Here, the ability of PC-VIPR to quantify changes in portal and splanchnic blood flow after a meal challenge was investigated. Results revealed significant increases in portal blood flow in response to the meal challenge, demonstrating the potential of PC-VIPR for monitoring of treatment such as beta-blockers and TIPS in patients with portal hypertension.

 
4052.   48 Assessment of tumour oxygenation in hepatocellular carcinoma with BOLD MRI at 3T: preliminary results
David Bowden1, Richard Black2, Lorenzo Mannelli3, Andrew Patterson1, Andrew N Priest2, Andrew B Gill2, Ilse Joubert1, Peter Beddy4, Owen Thomas1, and David J Lomas1
1Department of Radiology, Addenbrooke’s Hospital & University of Cambridge, Cambridge, Cambridgeshire, United Kingdom, 2Department of Medical Physics, Addenbrooke’s Hospital & University of Cambridge, Cambridge, Cambridgeshire, United Kingdom, 3Department of Radiology, University of Washington, Seattle, WA, United States, 4Department of Radiology, St.Jame's Hospital, Dublin, Ireland

 
Blood Oxygen Level Dependent (BOLD) MRI is a non-invasive technique that detects signal changes in tissues that occur in response to changes in blood flow. Technical challenges have presented significant barriers to its use outside the brain. Via the study of nine patients with hepatocellular carcinoma on a background of diffuse liver disease, we have demonstrated significant differences in BOLD effect between normal liver, diseased liver and primary liver tumours (HCC) at 3 Tesla using the simple challenge strategy of increased inspired oxygen. Normal, control subjects with healthy livers demonstrated no significant BOLD effect.
 
Electronic Poster Session - Body

Renal MRI
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  16:00 - 17:00

  Computer #  
4053.   49 Non-invasively Quantitative Measurements of Intrarenal R2' in Human Using an Asymmetric Spin Echo EPI Sequence
Xiaodong Zhang1, Yudong Zhang2, Xuedong Yang2, Xiaoying Wang1,2, Hongyu An3, Jue Zhang1,4, and Jing Fang1,4
1Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, 2Dept. of Radiology, Peking University First Hospital, Beijing, China,3Department of Radiology and Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 4College of Engineering, Peking University, Beijing, China

 
Renal R2 provides critically important information to assess the renal oxygen metabolism in both normal and disease states. An asymmetric spin echo (ASE) single shot echo planar imaging (EPI) sequence can provide rapid measurements of R2 in human kidney. In addition, the proposed ASE R2measurement is highly reproducible and is sensitive to renal oxygenation changes under pharmacological conditions

 
4054.   50 Mapping of Intra-Renal Oxygenation by Quantitative BOLD
Xiang He1, Ayaz Aghayev1, Serter Gumus1, Dmitriy A Yablonskiy2, and Kyongtae Ty Bae1
1Department of Radiology, University of Pittsburgh, Pittsburgh, PA, United States, 2Mallinckrodt Institute of Radiology, Washington University in St Louis, St Louis, Missouri, United States

 
While a semi-qualitative MR BOLD effect (R2*) has been widely adopted to assess intra-renal oxygenation, the underlying biophysical mechanism associating between hemodynamic parameters and renal BOLD effect (R2*) has not been established. In this study, a theoretical and experimental framework for MR-based quantitative BOLD (qBOLD) technique was investigated to measure absolute intra-renal blood oxygenation. A 2D GEPCI (Gradient Echo Plural Contrast Imaging) pulse sequence was used to measure T2* decay of renal MR signal. Our proposed renal-qBOLD method allows us to quantitatively assess regional renal blood oxygenation in the baseline state and under a renal physiological challenge.

 
4055.   51 Assessment of AKI severity in an ischemia/reperfusion mouse model using T2 mapping: Comparison with Neutrophil Gelatinase Associated Lipocalin (NGAL) and Kidney Injury Molecule-1 (KIM1)
Jan Hentschel1, Lajos Marko2, Erdmann Seeliger3, Dominik N. Müller2,4, Andreas Pohlmann1, and Thoralf Niendorf1,2
1Berlin Ultrahigh Field Facility (B.U.F.F.), Max-Delbrück-Center for Molecular Medicine (MDC), Berlin, Germany, 2Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max-Delbrück-Center, Berlin, Germany, 3Institute for Vegetative Physiology, Charité Medical Faculty, Berlin, Germany, 4Department of Experimental Medicine I, Nikolaus-Fiebiger-Center for Molecular Medicine, Friedrich-Alexander-University, Erlangen-Nürnberg, Germany

 
Renal medullary hypoperfusion and hypoxia play a pivotal role in acute kidney injury (AKI). This study examines the correlation between MRI and NGAL/KIM1 in mouse AKI including ischemia/reperfusion injuries of different severity to elucidate the link between changes in T2 and kidney physiology. The T2 values derived from the medulla and cortex of clipped kidneys showed a strong correlation with NGAL. A similarly strong correlation was observed between KIM1 and T2 deduced from the medulla. This indicates that T2 -mapping may be useful as a non-invasive marker for the characterization of pathophysiological changes in mouse models of AKI.

 
4056.   52 A reinvestigation of the feasibility and reproducibility of perfusion MRI in the kidneys
Wen-Chau Wu1,2, Mao-Yuan Su3, Chin-Cheng Chang3, and Kao-Lang Liu3
1Graduate Institute of Oncology, National Taiwan University, Taipei, Taiwan, 2Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan, 3Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan

 
Arterial spin labeling (ASL) and dynamic contrast enhanced (DCE) imaging are two established MRI techniques for quantitative perfusion measurement although their feasibility in the kidneys is still under investigation. One major challenge is glomerular filtration of the tracers used. Extended biophysical models have been proposed to account for dual outputs and/or inputs of tracers, which usually require additional scans and higher contrast-to-noise ratio (CNR). In this study, we assessed the feasibility and reproducibility of ASL and DCE in renal blood flow measurement using the original models and examined their CNR both in time and in space. Technical limitations were discussed.

 
4057.   
53 Quantifying the effects of hyperoxia on abdominal tissue T1
Eleanor F Cox1, Emma L Hall1, Paula L Croal1, Ian D Driver1, and Susan T Francis1
1SPMMRC, School of Physics & Astronomy, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom

 
The longitudinal relaxation time (T1) of tissues has been suggested to be a potential biomarker for tissue oxygenation and previous studies have seen a reduction in T1 on breathing 100% oxygen. We induced hyperoxia in 5 subjects at 3T, and using a modified respiratory triggered IR-TrueFISP sequence and formed maps of the change in R1 in the renal cortex, spleen and liver during normoxia and hyperoxia. There was a reduction in R1 in the spleen and renal cortex, but no change in R1 in the liver on hyperoxia.

 
4058.   
54 Breath Holding Has No Effect on BOLD Signal in the Kidney
Marla Shaver1, and Michael Noseworthy2,3
1School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada, 2School of Biomedical Engineering, Electrical and Computer Engineering, McMaster University, Hamilton, Ontario, Canada, 3Imaging Research Centre, St. Joseph's Healthcare, Hamilton, Ontario, Canada

 
In this study we used real-time BOLD imaging to investigate whether breath holding can play a significant role in modulating kidney microvasculature. Images were acquired using a T2* weighted GRE EPI sequence. Subjects were instructed to hold their breath, breath when necessary and repeat for the duration of the scan. Data from regions of interest for the renal cortex and medulla were analyzed to identify any trends in the data. No consistent trends were found and it was concluded that breath holding during the acquisition of renal BOLD MRI does not have an effect on the data.

 
4059.   55 Renal Oxygen Bioavailability in Healthy Volunteers and Patients with Well-functioning and Diseased Renal Transplants
Andrew L Wentland1,2, Arjang Djamali3, Shannon R Reese3, Sean B Fain1, Thomas M Grist2, Chris J Francois2, Amanda J Kolterman2, and Elizabeth A Sadowski2
1Medical Physics, University of Wisconsin School of Medicine & Public Health, Madison, WI, United States, 2Radiology, University of Wisconsin School of Medicine & Public Health, Madison, WI, United States, 3Nephrology, University of Wisconsin School of Medicine & Public Health, Madison, WI, United States

 
While individual studies have used BOLD imaging to evaluate renal oxygen bioavailability in transplant patients with various forms of allograft dysfunction, no study has compared measurements between these groups. We compared measurements of oxygen bioavailability in healthy subjects with native kidneys, subjects with well-functioning renal allografts, and transplant patients undergoing chronic allograft nephropathy, acute tubular necrosis, and acute rejection. Medullary oxygen bioavailability was significantly higher in subjects with acute rejection than in the other four groups. No other significant differences were found. The inclusion of an MR perfusion technique in future studies may elucidate the mechanisms behind these abnormal measurements.

 
4060.   56 Feasibility of regional renal blood flow and vascular volume fraction measurement with cardiac-output corrected MR renography
Jeff L. Zhang1,2, Henry Rusinek3, Christopher Conlin1,2, and Vivian S. Lee1
1Department of Radiology, University of Utah, Salt Lake City, UT, United States, 2Department of Bioengineering, University of Utah, Salt Lake City, UT, United States, 3Department of Radiology, New York University

 
In this study we performed a voxel-by-voxel analysis for the vascular phase of low-dose Gd-enhanced MR renography data and assessed the impact of cardiac output-corrected AIF on the precision of renal perfusion measurements. The estimated perfusion and vascular volume fraction agreed with literature value. The variability of perfusion was remarkably reduced with the use of CO-based AIF correction.

 
4061.   57 Time course study on the effects of iodinated contrast medium on intrarenal water transport function using diffusion-weighted MRI
Jing Wang1, Yudong Zhang2, Xuedong Yang2, Xiaoying Wang1,2, Jue Zhang1,3, Jing Fang1,3, and Xuexiang Jiang2
1Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China, 2Department of Radiology, Peking University First Hospital, Beijing, China, 3College of Engineering, Peking University, Beijing, China

 
This study is aim to assess the effects of intravenous-injected iodinated contrast medium on intrarenal water diffusion using noninvasive DW-MRI. A sequential DW-MRI was performed on rabbit model to estimate the intrarenal apparent diffusion coefficient at 24 hours before and 1h, 24h, 48h and 72h after administration. As demonstrated by DW-MRI, intravenous iopamidol injection resulted in a successive reduction of intrarenal water diffusion, particularly in IS of kidney. This MR technique may be used as a noninvasive tool to perform a time course study of the pathogenesis associated with contrast-induced nephropathy.

 
4062.   58 MR Elastography of Renal Transplants: Correlating Stiffness with Interstitial Fibrosis and Tubular Atrophy
Sudhakar Kundapur Venkatesh1, Gang Wang1, Thomas Paulraj Thamboo2, Eugene Liu1, Edwin PY Siew1, and Vathsala Anantaram3
1Diagnostic Imaging, National University Health System, Singapore, Singapore, Singapore, 2Pathology, National University Health System, Singapore, Singapore, Singapore, 3Nephrology, National University Health System, Singapore, Singapore, Singapore

 
Chronic allograft nephropathy is a common cause of renal transplant failure and characterized by interstitial fibrosis and tubular atrophy-IFTA. We investigated transplant stiffness and correlated with histological grade of IFTA. Our study did not show any significant correlation with stiffness and grade of IFTA suggesting that other changes including tubular atrophy, glomerulosclerosis and arteriolar hyalinosis and altered perfusion may contribute significantly to stiffness. Our study did show significant differences between normal group and those with IFTA. More work is needed for determining the utility of renal transplant stiffness measurement with MRE and its relation to the histological changes.

 
4063.   59 Intra-renal oxygenation by BOLD MRI in Rat Model of Contrast Induced Nephropathy: Evaluation by R2* and R2'
Lu-Ping Li1, Hongyu An2, Tammy Franklin1, Ujala Bokhary1, Anindya Sen1, and Pottumarthi V Prasad1
1Radiology Dept., Northshore University Healthsystem, Evanston, IL, United States, 2Radiology, University of North Carolina, Chapel Hill, NC, United States

 
R2* is widely used as a renal BOLD MRI parameter, but is inherently dependent on R2 in addition to the susceptibility induced relaxation, R2’. R2’ can be estimated using asymmetric spin echo (ASE) sequence. Preliminary data from 26 rats were acquired with this sequence before and after administration of iodinated contrast agents in a model of CIN. Our preliminary experience supports the feasibility of acquiring R2’ maps using ASE-EPI sequence in kidneys and that the similar trends observed with R2* and R2’ suggests that measured changes in R2* are primarily due to changes in susceptibility.

 
4064.   60 Regional BOLD parameters are correlated with renal filtration and perfusion in healthy human kidneys
Jeff L. Zhang1,2, Henry Rusinek3, Christopher Conlin1,2, and Vivian S. Lee1
1Department of Radiology, University of Utah, Salt Lake City, UT, United States, 2Department of Bioengineering, University of Utah, Salt Lake City, UT, United States, 3Department of Radiology, New York University

 
As microprobe pO2 technique is not applicable for human kidneys, direct correlation between R2* and tissue pO2 has never been studied in human subjects. In order to validate BOLD as a marker of renal oxygenation we have measured the correlation (CC) between BOLD signal and renal functional parameters such as glomerular filtration rate (GFR) and tissue perfusion (F) in normal human kidneys. The strongest associations (CC > 0.60) were found for GFR/FMed vs R2*Med (0.68), GFR/FCx vs R2¡¯Cx (0.65), and GFR/FMed vs R2¡¯Med (0.62).

 
4065.   61 In vivo Quantification of Renal Lipid in Diabetic Mice by Magnetic Resonance Imaging
Xingui Peng1, Shenghong Ju1, Fang Fang1, and Gao-Jun Teng1
1Medical School, Southeast University, Nanjing, Jiangsu province, China

 
Diabetic nephropathy has been associated with the presence of lipid deposits. This study aimed to determine whether in vivo MR imaging can evaluate the lipid changes noninvasively. Chemical shift imaging and T1WI were performed to measure lipid content and estimate adipose tissue distribution, respectively. Visceral adipose tissue and kidney lipid content in db/db mice was significantly higher than that of control group. The lipid accumulation in the renal cortex of db/db mice was significantly higher than that of renal medulla. Out results indicate that MRI will be used to study animal models and patients with renal diseases resulting from lipotoxicity.

 
4066.   62 Histogram Analysis to Evaluate Changes on Parametric Maps: Preliminary Application to Renal BOLD MRI
Anindya Sen1, Lu-Ping Li1, Ujala Bokhary1, Ioannis Koktzoglou1, and Pottumarthi V. Prasad1
1Department of Radiology, Northshore University Healthsystem, Evanston, IL, United States

 
Parametric maps, e.g. T1, T2, ADC (apparent diffusion coefficient) etc. are routinely used to evaluate functional changes in tissue. Regions of interest (ROI) measurements are commonly employed to evaluate the observed changes which may not fully characterize the spatial variations in the measurements inherently present in images. In this preliminary study, we have evaluated a histogram based analysis of R2* maps for renal BOLD MRI. Using centroid to represent the histogram distribution, we show that the displacement in the geometric centroids obtained pre- and post-furosemide could be used as a parametric measure for change.

 
4067.   63 Quantitative Multi-parametric MRI Evaluation of Kidneys in Subjects with CKD
Pottumarthi V. Prasad1, Lu-Ping Li1, Muhammad Haque1, Anindya Sen1, Ujala Bokhary1, Heather Koenigs1, Rajiv Agarwal2, and Stuart Sprague3
1Radiology, NorthShore University HealthSystem, Evanston, IL, United States, 2Medicine, Indiana University, Indianapolis, IN, United States, 3Medicine, NorthShore University HealthSystem, Evanston, IL, United States

 
Chronic kidney disease (CKD) involves progressive reduction in renal function and is associated with increasing levels of fibrosis and reduction in renal volume. Additionally, it is becoming clear that hypoxia plays a key role both in the initiation and progression of CKD. Here, preliminary data of renal volume, ADC and BOLD MRI measurements obtained in patients with CKD and healthy controls are presented. It is evident that enhanced hypoxia is present even at mild to moderate levels of CKD and there was correlation between R2* and ADC values, consistent with the hypothesis that hypoxia stimulates fibrogenesis.

 
4068.   64 P904-USPIO enhanced MR-imaging of ischemic acute renal failure and Cyclosporin A toxicity in a rat model on a clinical 3T scanner
Henrik J Michaely1, Urs Benck2, Stefan Haneder3, Uwe Göttmann4, Tobias Runge4, Bernhard K Krämer4, and Stefan O Schoenberg3
1IKRN, University Medical Center Mannheim, Mannheim, Ba-Wu, Germany, 2V. Medical Clinic, University Medical Center Mannheim, Mannheim, 3IKRN, University Medical Center Mannheim, 4V. Medical Clinic, University Medical Center Mannheim

 
3T MR-imaging of rats with acute ischemic renal failure, Cyclosporin A toxicity and control was performed 36h after injection of ultra small particles of iron oxide (P904). Only in the acute renal failure signal decay in the medulla was seen which correlated with positive iron findings and Ed1 positive macrophages in immunohistology.

 
4069.   65 Imaging the pH changes in a glycerol-induced acute kidney injury mouse model with a MRI-CEST pH-responsive contrast agent
Dario Livio Longo1, Alice Busato1, Stefania Lanzardo2, Federica Antico3, and Silvio Aime1
1Molecular Imaging Center, University of Torino, Torino, Italy, 2Department of Clinical and Biological Sciences, University of Torino, Torino, Italy,3Department of Internal Medicine, University of Torino, Torino, Italy

 
pH is an important microenvironment parameter, in fact a number of disease states are associated with alterations in pH, such as ischemia, inflammation, infection and cancer, and many kidney injuries are associated with a perturbation of renal pH, therefore imaging techniques able to report in vivo on pH modifications would have a great relevance. The aim of the work was to investigate the use of Iopamidol as a MRI-CEST pH reporter of the disease evolution in glycerol-induced AKI model, exploiting the capability to image pH values in different regions for single kidneys.

 
4070.   66 Quantitation of renal perfusion in an animal model at 3T: A comparison between ASL and DCE-MRI
Fabian Zimmer1, Frank G. Zoellner1, Simone Hoeger2, Sarah Klotz2, Charalambos Tsagogiorgas3, and Lothar R. Schad1
1Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Germany, 2Department of Medicine V, University Medical Centre Mannheim, Heidelberg University, Mannheim, Germany, 3Clinic for Anaesthesiology and Intensive Care, Heidelberg University, Mannheim, Germany

 
The assessment of kidney function by measuring renal microvascular perfusion is crucial to diagnose and treat renal diseases at an early stage of progression. MRI provides two techniques to assess renal perfusion: Dynamic contrast-enhanced (DCE)-MRI and arterial spin labelling (ASL). In this study, ASL has been established to quantitatively measure renal cortical perfusion in rats with unilateral ischaemic acute renal failure. The ASL estimates were compared against those obtained by DCE-MRI. Both methods are in good agreement and show no statistical differences. Furthermore, both methods depict significant blood flow differences between healthy and diseased kidneys.

 
4071.   67 Serial Assessment of Renal Anatomy and Function in Mice with Unilateral Ureteral Obstruction Using Multi-modal Imaging
C. Chad Quarles1, Feng Weng1, Mohammed Tantawy1, Rosie Jiang2, Keiko Takahashi2, Chuan-Ming Hao2, Todd Peterson1, Raymond Harris2, and Takamune Takahashi2
1Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 2O'Brien Mouse Kidney Physiology and Disease Center, Vanderbilt University, Nashville, TN, United States

 
MRI and 99m Tc-MAG3 scintigraphy were used to serially assess the mouse kidney following unilateral ureteral obstruction (UUO). In UUO mice the renal pelvic space gradually expanded in obstructed kidneys as early as 1 day post ureteral ligation and the components of renal medulla, especially inner medulla and papilla, was remarkably decreased as the disease progressed. The 99m Tc-MAG3 data revealed that renal perfusion is remarkably and rapidly reduced in UUO kidneys, whereas it is gradually increased in contra-lateral kidneys. In pre-clinical models of renal disease, these imaging techniques could be effective tools for elucidating pathological mechanisms of obstructive kidney disease.

 
4072.   68 3D BOLD of Kindey: Impact of high PAT Factors
Tanja Gaa1, Frank Zoellner1, Florian Lietzmann1, and Lothar Schad1
1Medical Faculty Mannheim, Heidelberg University, Computer Assisted Clinical Medicine, Mannheim, Germany

 
High PAT (Parallel Acquisition Technique) factors were used to reduce the acquisition time and also to receive a good image and fit quality for 3D BOLD imaging of the human kidney. The measurement delivers constant R2* values (medulla: 42.7 to 44.7 1/s, cortex: 22.7 to 24.6 1/s). The fit quality of the R2 fit does not change with higher PAT factors as well (medulla: 0.95 to 0.98, cortex: 0.93 to 0.95). The acquisition time and therefore, the breathhold time for the patient could be reduced from 40 seconds for PAT 1 to 15 seconds for PAT 6.

 
4073.   69 Intra-Renal Oxygenation in Contrast Induced Nephropathy Model by BOLD MRI: Comparison of Four Radio-Contrast Agents
Lu-Ping Li1, Hongyan Du2, Tammy Franklin1, Ujala Bokhary1, Maria Papadopoulou-Rosenzweig3, Richard Solomon4, and Pottumarthi V Prasad1
1Radiology Dept., Northshore University Healthsystem, Evanston, IL, United States, 2Center for Clinical & Research Informatics, Northshore University Healthsystem, Evanston, IL, United States, 3Radiation Oncology, Northshore University Healthsystem, Evanston, IL, United States, 4Medicine, Fletcher Allen Health Care, Burlington, VT, United States

 
Radio-contrast induced nephropathy (CIN) is the 3rd common cause of in-hospital mortality in patients with pre-existing kidney insufficiency. Physico-chemical properties of the contrast media are known to influence their risk profile. Renal hypoxia is known to play a role in the pathophysiology of CIN and BOLD MRI has been shown to be useful in monitoring the changes in intra-renal oxygenation following administration several pharmacological agents including radio-contrast media. Here, we report for the first time, a direct comparison among four radio-contrast agents with different physic-chemical properties (monomer/dimer, iconicity, osmolality, viscosity) using BOLD MRI.

 
4074.   70 Modelling for MR renography: accurate and precise GFR using a two-compartment model
Benjamin Dickie1, Constantina Chrysochou2, Su Wei Lim1, Philip A Kalra2, David L Buckley1, and Steven Sourbron1
1Division of Medical Physics, University of Leeds, Leeds, Yorkshire, United Kingdom, 2Department of Renal Medicine, Salford Royal Hospital, Manchester, United Kingdom

 
The aim of this study was to identify the reason for the bias in single-kidney glomerular filtration rate (SK-GFR) derived from a two-compartment filtration model. Three hypotheses were investigated: (I) water reabsorption is modelled incorrectly; (II) the model is not suitable for whole-kidney curves; (III) the tubuli are not well-mixed. 64 kidneys with known Isotope SK-GFR served as a basis for comparison. The results show that hypothesis (III) explains the bias. Assuming instead a plug-flow model for the tubulus eliminates the bias and increases the precision, without compromising the quality of the fit or increasing the number of free parameters.

 
4075.   71 Functional MR Imaging of Kidneys
Eito Kozawa1, Tsutomu Inoue2, Waka Mizukoshi3, Naoko Nishi4, Hiromichi Suzuki2, and Fumiko Kimura3
1Imaging Diagnosis, Saitama Medical University, International Medical Center, Hidaka-shi, Saitama, Japan, 2Nephrology, Saitama Medical University, Japan, 3Imaging Diagnosis, Saitama Medical University, International Medical Center, Japan, 4Saitama Medical University, International Medical Center, Japan

 
Functional renal MRI techniques together over morphological criteria can improve MRI specificity.

 
4076.   72 MR imaging of male urethral injury
Masahiro Horikawa1, Hiroshi Shinmoto1, Akio Horiguchi2, Shigeyoshi Soga1, Eisuke Shiomi1, Shigeru Kosuda1, and Tatsumi Kaji1
1Radiology, National Defense Medical College, Tokorozawa, Saitama, Japan, 2Urology, National Defense Medical College, Tokorozawa, Saitama, Japan

 
Urethral injury occurs as a result of trauma or iatrogenic cause. Retrograde urethrography is a gold standard to evaluate disruption of involved urethra, however, MR imaging has been reported to be useful to assess the extent of injury and presence of hematoma or fibrosis. The purpose of this exhibit is to demonstrate various patterns of urethral injury and to show the advantage of MR imaging in perioperative management thorough case presentations, ranged from common blunt trauma to rare condition such as urethrocutaneous fistula after sex transformation surgery.
 
Electronic Poster Session - Body

Body MRI (Miscellaneous & Diabetes)
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  17:00 - 18:00

  Computer #  
4077.   
49 Evaluation of Imatinib Mesylate as a Possible Treatment for Nephrogenic Systemic Fibrosis in a Rat Model
Thomas A. Hope1, Philip LeBoit2, Whitney A. High3, Yanjun Fu4, and Robert C. Brasch4
1Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States, 2Dermatology, UCSF, San Francisco, CA, 3Dermatology, University of Colorado, Denver, CO, 4Radiology, UCSF, San Francisco, CA

 
We have evaluated the efficacy of imatinib mesylate for the treatment of nephrogenic systemic fibrosis in a high dose GBCA animal model and have demonstrated that the administration of imatinib results in decreased lesion severity suggesting that imatinib may be effective in the treatment of NSF in humans.

 
4078.   50 Relaxivities of Conventional and Protein-Binding Gd-Based Contrast Agents in Human Blood and their Implications for Dosing in CE-MRA
Jeffrey Harold Maki1,2, Gregory J Wilson3, Miles A Kirchin4, Sarah Bastawrous2, and Puneet Bhargava2
1Radiology, University of Washington, Seattle, WA, United States, 2Radiology, Puget Sound VAHCS, Seattle, WA, United States, 3MR Clinical Science, Philips Medical, Cleveland, OH, United States, 4Medical Affairs, Bracco Diagnostics, Milan, Italy

 
High-relaxivity protein-binding contrast agents are believed to improve contrast-enhanced MRA. To effectively use these agents, knowing their true r1 and r2 relaxivities in human blood at MRA concentrations is vital. In vitro relaxivity measurements (gadoteridol, gadobenate, gadofosveset) were performed in human blood at concentrations to 20 mmol (1.5, 3T). R1 and R2* were non-linear vs. [Gd] such that relaxivities r1 and r2* depended highly on [Gd]. At low concentrations r1 relaxivity behaved approximately per labeling data, but >3mmol the r1 of all agents decreased and became similar. This and r2* effects suggest higher Gd doses may be detrimental for CE-MRA.

 
4079.   51 Single-Phase Ultrasmall GdEuO3 Nanoparticles as Dual Imaging Agent: T1 MRI-Fluoresceince Imaging Agent
Wenlong Xu1, Krishna Kattel1, Ja Young Park1, Badrul Alam Bony1, Woo Choul Heo1, Tirusew Tegafaw Mengesha1, and Gang Ho Lee1
1Department of chemistry, Kyungpook National University, Daegu, Korea

 
The single-phase mixed ultrasmall GdEuO3 nanoparticles are potential candidates for dual imaging experiment.It emerges as a new and advanced imaging technique in clinical applications. It is expected that it will play a key role to diagnose diseases by replacing conventional single-imaging techniques. We developed a simple one-step synthesis of lactobionic acid surface-modified ultra small GdEuO3 nanoparticles. It was well characterized by using MP-XRD, TEM, FT-IR spectrophotometer, TGA, confocal microscope, SQUID magnetometer and Magnetic Resonance Imaging (MRI) instrument.

 
4080.   52 High-resolution MR lymphangiography in mice using double contrast agents at 11.7 T
Yuki Mori1, Punniyakoti Thanikachalam Veeraveedu2, Yutaka Komai2, and Yoshichika Yoshioka1
1Biofunctional Imaging, WPI IFReC, Osaka University, Suita, Osaka, Japan, 2Single Molecule Imaging, WPI IFReC, Osaka University

 
This study investigated to visualize the lymphatic structures of healthy mice on high-resolution three-dimensional manganese–enhanced MRI (3D-MEMRI) at 11.7 T. Furthermore, we try to discriminate lymphatic vessels from blood streams with double contrast agents administration of interstitial manganese chloride solution (MnCl2) as a positive contrast agent for lymphatic vessels and intravenous micron-sized particles of iron oxide (MPIOs) as negative contrast for vein, respectively. Interstitial administration of MnCl2 resulted in a fast and high accumulation in lymph nodes and depicted lymphatic vessels clearly. In addition, simultaneous administration of interstitial MnCl2 and intravenous MPIOs discriminated lymphatic vessels from blood vessels.

 
4081.   53 Manganese Oxide Doped Gadolinium Oxide Nanoparticles for both T1 and T2 MRI Contrast Agent
BADRUL ALAM BONY1, Ja Young Park2, Krishna Kattel3, Wenlong Xu3, Woo Choul Heo3, Tirusew Tegafaw Mengesha3, and Gang Ho Lee3
1Chemistry, Kyungpook National University, Daegu, Korea, 2Kyungpook National University, Kazakhstan, 3Kyungpook National University

 
We have developed ultra-small gadolinium oxide nanoparticles, which are surface-doped with manganese oxide abbreviated as Gd2O3@MnO. In this work, the surface doped gadolinium oxide nanoparticles with an average d of 1 to 2 nm, which can be dispersed homogeneously. They were further coated with hydrophilic biocompatible lactobionic acid. It shows high relaxivity than normal ultrasmall gadolinium oxide nanoparticle. In-vitro tests of the sample solution indicated clear dose-dependent contrast enhancements in both T1 and T2 map images, showing that the nanoparticles may be used as both T1 and T2 MRI contrast agents.

 
4082.   54 Effects of in vivo Flip Angle Variations on the Accuracy of DCE-MRI Perfusion Parameters at 1.5T and 3.0T
Jiangsheng Yu1, Xia Zhao1, Yiqun Xue1, Mark A Rosen1, Christina S Chu2, and Hee Kwon Song1
1Departments of Radiology, University of Pennsylvania, Philadelphia, PA, United States, 2Obstetrics and Gynecology, University of Pennsylvania, Philadelphia, PA, United States

 
The goal of this work is to determine to what extent flip angle deviations affect DCE-MRI perfusion parameter accuracy on three different MRI systems, including whether higher fields and short bore systems can potentially exacerbate these measurement inaccuracies. The results show that over a large region of the body, the ranges of flip angle deviations are similar for the three systems. These variations can potentially mask true changes in tumor treatment response, and flip angle mapping may be a crucial in DCE-MRI protocols.

 
4083.   55 Synthesis and characterization of ultrasmall gadolinium oxide nanoparticles for advance T1 MRIcontrast agent
Woo Choul Heo1, Ja Young Park1, Kattel Krishna1, Wenlolg Xu1, Tirusew Tegafaw Mengesha1, Badrul Alam Bony1, and Gang Ho Lee1
1Department of Chemistry, Kyungpook National University, Daegu, Korea

 
We reported the synthesis and characterization of ultrasmall gadolinium oxide nanoparticles. In this work, the ultrasmall gadolinium oxide nanoparticles with an average d of 1 nm having r1 of 9.9 s-1 mM-1, which is much larger than those of Gd(III)-chelates. It seems that surface Gd(III) ions in gadolinium oxide nanoparticles cooperatively induce the longitudinal relaxation of the water proton. As a result, this cooperative induction effect accelerates the longitudinal relaxation of the water proton, providing a larger r1 than Gd(III)-chelates. We address this by carefully examining the d dependence of r1. We finally took in vivo T1 MR images of a rat with a brain tumor by using D-glucuronic acid coated ultrasmall gadolinium oxide nanoparticles and observed a clear contrast enhancement in T1 MR images of the tumor after injection.

 
4084.   56 Fully Automated Measurements of Longitudinal and transverse Relaxation Times of MRI Contrast Agent
Lijia Wang1, Thanh D. Nguyen2, Mengchao Pei2,3, Jianqi Li3, and Yi Wang2,3
1Shanghai Key Laboratory of Magnetic Resonance, East China Normal University, Shanghai, Shanghai, China, 2Weill Cornell Medical College, New York, NY, United States, 3Shanghai Key Laboratory of Magnetic Resonance,East China Normal University, Shanghai, Shanghai, China

 
A fully automated software-based T1 and T2 measurement method is proposed for phantom studies to shorten processing time and improve reproducibility. This method was validated on phantom data acquired from 77 doped water samples by comparing with manual measurements. Excellent T1 and T2 agreement was found between the two methods, while the processing time was reduced by thousands of times by the automated method

 
4085.   57 Optimisation of the Bolus and Infusion Protocol for Equilibrium Magnetic Resonance Imaging
Catherine Mallik1, Steve Bandula2, Scott Rice2, David Atkinson2, Stuart Taylor2, James Moon3, and Shonit Punwani2
1Centre for Medical Image Computing, University College London, London, United Kingdom, 2UCL Centre for Medical Imaging, University College London Hospital, United Kingdom, 3Imaging Centre, The Heart Hospital, University College London Hospital, London

 
Changes in the fractional volume of the extravascular, extracellular space (VEES) can be indicative of pathology. Equilibrium MRI (EQ-MRI) is a recently proposed technique to measure VEES, provided a constant concentration is reached between the contrast agent in the blood pool and tissue of interest. A pharmacokinetic model of a bolus and infusion protocol was devised to predict an optimal infusion rate and the time when equilibrium would be reached over a range of Ktrans values incorporating both diseased and healthy tissue. Pilot data collected in a control is indicative that equilibrium was reached in normal liver and muscle tissue.

 
4086.   58 Synthesis and Properties of Gadolinium Iodate Nanoparticles as a MRI/CT Contrast Agnet
Ja Young Park1, Krishna Kattel1, Wenlong Xu1, Badrul Alam Bony1, Woo Choul Heo1, Tirusew Tegafaw Mengesha1, and Gang Ho Lee1
1Department of Chemistry, Kyungpook National University, Daegu, Korea

 
The present work deals with bimodal imaging agent which emerges as new and efficient imaging techniques in clinical applications. D-glucuronic acid surface-coated ultra-small gadolinium iodate nanoparticles have been synthesized and well characterized. It may be used for both MRI contrast agent and CT contrast agent. Finally, we took in vivo T1 MR images and CT images of a rat with a brain tumor by using D-glucuronic acid coated ultrasmall gadolinium iodate nanoparticles. We observed a clear contrast enhancement in MR images and CT images of the tumor after injection of nanocolloid.

 
4087.   59 A 10-minute Comprehensive Liver MRI Protocol at 3.0T: Application of Novel Breath-hold Sequences and a Simultaneous Scanning and Reconstruction Algorithm
Shahid M Hussain1, Jeremy Van Tilburg2, Mariah Smith-Miloff1, and Thomas G. Perkins3
1Department of Radiology, University of Nebraska Medical Center, Omaha, NE, United States, 2The Nebraska Medical Center, United States, 3Philips Healthcare, Cleveland, OH, United States

 
Compared to abdominal CT, current liver MRI exams are relatively long (often approx. 30 minutes vs. <5 min for CT). The introduction of 3.0T with higher SNR, phased array coils, parallel imaging techniques, and novel sequences allow us to perform real-time scanning and reconstruction. Decreasing imaging time should affect patient compliance and result in a more economic use of MRI machines, while providing a time-competitive alternative to CT examinations. Our results show that a 10-minutes comprehensive liver MRI protocol at 3.0T is feasible by the application of novel breath-hold sequences and a simultaneous scanning and reconstruction algorithm.

 
4088.   60 Characterization of Diffuse Liver Disease Using the T2 of the Water Component and Fat Fraction
Tomoe Barr1, Phillip Kuo2, Judith Pugh3, Charmi Patel3, Horacio Rilo4, Scott Squire2, Thomas Boyer5, and Maria I Altbach2
1Biomedical Engineering, University of Arizona, Tucson, AZ, United States, 2Radiology, University of Arizona, United States, 3Pathology, University of Arizona, United States, 4Surgery, University of Arizona, United States, 5Medicine, University of Arizona, United States

 
Chronic liver disease due to Hepatitis B/C infection or non-alcoholic steatohepatitis (NASH) is a major health problem in the USA and worldwide. The diagnosis of these pathologies requires a liver biopsy which is an invasive procedure with associated morbidity and cost and subject to sampling errors. Thus non-invasive imaging methods are actively being sought. In this work we use a novel radial gradient and spin-echo (RADGRASE) method which provides T2 of the water component and fat fraction maps from data acquired in a breath hold. These parameters are used to characterize changes in the liver due to inflammation, fibrosis, and steatosis in subjects with suspected of chronic liver disease.

 
4089.   61 Body composition analysis using MRI, Dual Energy X-ray Absorptiometry and Bio-impedance
Rama Jayasundar1, Ankur Poddar2, Ariachery Ammini3, and Ashok Kumar Mukhopadhyay4
1Department of NMR, All India Institute of Medical Sciences, New Delhi, Delhi, India, 2Department of Biotechnology, All India Institute of Medical Sciences, New Delhi, Delhi, India, 3Department of Endocrinology, All India Institute of Medical Sciences, New Delhi, Delhi, India, 4Department of Laboratory Medicine, All India Institute of Medical Sciences, New Delhi, Delhi, India

 
In this study on 30 volunteers, fat (considered a risk factor for some diseases) assessed using MRI, Dual Energy X-ray Absorptiometry (DEXA) and Bio-impedance analysis (BIA) are compared and correlated. The results indicate the following : MRI evaluated abdominal fat correlated well with trunk fat (DEXA) and body fat (BIA); good correlation between measurements in thigh region (MRI) and legs (DEXA); while abdominal fat is an indicator of body fat, that from the thigh region is not. The three techniques can be used interchangeably for estimating abdominal fat but MRI has the additional advantage of giving information on fat distribution.

 
4090.   62 Chemical-Shift MRI Measurements of Variations in Murine Brown Adipose Tissue Fat Content Due to Housing Temperature
Houchun Harry Hu1,2, Daniel Larry Smith, Jr.3, Yongbin Yang3, Guihua Zhai4, and Tim R. Nagy3
1Radiology, Children's Hospital of Los Angeles, Los Angeles, California, United States, 2Electrical Engineering, University of Southern California, Los Angeles, California, United States, 3Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama, United States, 4Radiology, University of Alabama at Birmingham, Birmingham, Alabama, United States

 
Brown adipose tissue (BAT) is involved in non-shivering thermogenesis. When stimulated, it metabolizes its fat stores to produce heat and maintain body temperature. We utilize chemical-shift MRI at 9.4T to measure BAT fat content in 3 groups of mice (n=16/group) that were singly housed at 16-cold, 23-room, and 30-warm degrees Celsius over four weeks. We demonstrate that BAT fat-signal fraction measured at week 4 is positively correlated with housing temperature (cold-50.4±8.0%, room-60.8±11.9%, hot-79.4±12.1%) and significantly different between groups (p<0.01). Results demonstrate the differential thermal demand of animals in each group and prove that chemical-shift MRI can reflect BAT activity in vivo.

 
4091.   63 Quantification of Renal Lipid and Oxygenation in Diabetic Mice by Magnetic Resonance Imaging
Shenghong Ju1, Xin-gui Peng1, and Gao-jun Teng1
1Department of Radiology, Zhongda Hospital, Southeast University, Nanjing, Jiangsu, China

 
To study the feasibility of in vivo MR measurement of lipid accumulation and oxygenation in kidney using the diabete (db/db) mouse model

 
4092.   
64 In vivo substrate oxidation in skeletal muscle of mice
Patricia Maria Nunes1, Alan James Wright1, Cees Tack2, and Arend Heerschap1
1Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands, 2Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, Gelderland, Netherlands

 
A mouse-scale 13C MRS method was developed, to enable the evaluation of knockout mice in vivo for skeletal-muscle substrate oxidation at the level of TCA cycle. [2-13C]acetate or [2,4,6,8-13C]octanoate was infused and yielded sufficient 13C labelling in glutamate C4/C2. Half-maximal 13C enrichments during acetate and octanoate infusion were respectively, 7.2±1.8min and 30.7±4.2min for glutamate C4, and for glutamate C2 19.9±3.9min and 38.3±11.8min. Relative anaplerotic contribution for TCA-cycle flux were similar in both acetate and octanoate infusions with 0.40±0.10 and 0.42±0.20. This study shows the feasibility of 13C MRS to compare in vivo fatty-acid oxidation and TCA-cycle kinetics in mouse’ skeletal-muscle.

 
4093.   65 Oxygen Bioavailability and Pulse Wave Velocity in Patients with Metabolic Syndrome
Andrew Louis Wentland1,2, Nancy K Sweitzer3, Oliver Wieben1, Elizabeth A Sadowski2, Thomas M Grist2, and Chris J Francois2
1Medical Physics, University of Wisconsin School of Medicine & Public Health, Madison, WI, United States, 2Radiology, University of Wisconsin School of Medicine & Public Health, Madison, WI, United States, 3Medicine, University of Wisconsin School of Medicine & Public Health, Madison, WI, United States

 
It is hypothesized that arterial stiffening in patients with metabolic syndrome (MS) will lead to elevated aortic pulsatility and subsequent renal barotrauma. The purpose of this study was to assess aortic stiffness and renal oxygen bioavailability in MS patients using MR-based pulse wave velocity (PWV) and BOLD techniques. PWV and medullary oxygen bioavailability were significantly greater in MS patients than in healthy volunteers. The association of increased PWV and altered renal tissue oxygenation, as well as the known increase in renal dysfunction with advanced MS, suggests that arterial stiffening may play a causal role in renal dysfunction and future risk.

 
4094.   66 Pulse Wave Velocity in Adolescent Girls with Risk Factors for Metabolic Syndrome
Christopher J François1, Valentina Taviani2, Jennifer L Rehm3, Christopher J Hardy4, Ellen L Connor3, and Scott B Reeder1,2
1Radiology, University of Wisconsin, Madison, WI, United States, 2Medical Physics, University of Wisconsin, Madison, WI, United States, 3Pediatrics, University of Wisconsin, Madison, WI, United States, 4GE Global Research, General Electric, Niskayuna, NY, United States

 
Vascular stiffness is one of the earliest predictors of future cardiovascular disease (CVD). However, it is incompletely understood how various risk factors for CVD lead to vascular stiffening. Emerging evidence suggests that hepatic steatosis may play an important role in the development of CVD in adults. In this study we demonstrate the feasibility of assessing pulse wave velocity (PWV), a well established bio marker of vascular stiffness, hepatic fat fraction (HFF), visceral adipose tissue (VAT) and subcutaneous adipose tissue (SCAT) in adolescent girls with risk factors for metabolic syndrome.

 
4095.   67 Quantitative in vivo 19F MRI of transplanted pancreatic islets using clinically applicable, non-emulsion nanoparticles
Mangala Srinivas1, Karolina Andralojc2, Andor Veltien3, Maarten Brom2, Leike Joosten2, Arend Heerschap3, Jolanda de Vries1, Carl Figdor1, Otto Boerman2, and Martin Gotthardt2
1Tumor Immunology, RUNMC, Nijmegen, Gelderland, Netherlands, 2Nuclear Medicine, RUNMC, Nijmegen, Gelderland, Netherlands, 3Radiology, RUNMC, Nijmegen, Gelderland, Netherlands

 
Pancreatic islet transplant is a promising treatment for type I diabetes. However, islet survival and function is poor post-transplant. Here, we describe a non-emulsion based multimodal agent that is able to penetrate the membrane capsule around islets, and allows for quantitative in vivo 19F MRI, and fluorescence imaging. Labeling had minimal effects on viability and insulin secretion. We present preliminary imaging data in mice that received transplanted, labeled islets. Furthermore, islets remain detectable for at least two weeks post-transplant. Histology confirmed that the label is confined to the transplanted islets. The technique is potentially applicable to longterm, quantitative islet tracking.

 
4096.   68 Concentrations of Glycogen and Choline Compounds in Human Liver Measured with 1H-MRS at 3T
Ronald Ouwerkerk1, Ahmed Medhat Gharib1, Monica Skarulis2, and Roderic I Pettigrew1,3
1Metabolic Imaging Branch, NIDDK/NIH, Bethesda, MD, United States, 2CLINICAL ENDOCRINE SECT, NIH/NIDDK, Bethesda, MD, United States,3NIH/NIBIB, Bethesda, MD, United States

 
Navigator gated single volume 1H-MRS was used after B0 field mapping and manual shimming to obtain high quality liver spectra that allowed quantification of choline and glycogen, important metabolic markers in humans. Narrow line widths allowed more selective water suppression, avoiding saturation of glycogen. The T2’s of glycogen, choline water and lipid were measured and used to estimate the absolute concentrations of metabolites. Average concentration of MRS visible choline compounds in eleven healthy volunteers was 16.9±4.5 mmol/kg ww; the concentration of glycogen glycosyl units was 78±36 mmol/kg ww. In-vivo measurement of liver choline and glycogen with 1H-MRS can be an important tool for the study of metabolic disorders.

 
4097.   69 Visceral adipose tissue volume measurement using MRI, and its relation with liver elastography and anthropometry, in type 2 diabetic patients.
Cristóbal Martín Serrano García1,2, Francisco Barrera3, Hugo Vidal4, Carlos Riquelme4, Pilar Labbé3, Jessica Liberona5, Marco Arrese3, Francisco Cruz4, Claudia Prieto2,6, Pablo Irarrázaval2,6, Cristián Tejos2,6, and Sergio Uribe2,4
1Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Región Metropolitana, Chile, 2Biomedical Imaging Center, Pontificia Universidad Católica de Chile, Santiago, Región Metropolitana, Chile, 3Gastroenterology, Pontificia Universidad Católica de Chile, Santiago, Región Metropolitana, Chile, 4Radiology, Pontificia Universidad Católica de Chile, Santiago, Región Metropolitana, Chile, 5Nutrition & Diabetes, Pontificia Universidad Católica de Chile, Santiago, Región Metropolitana, Chile, 6Electrical Engineering, Pontificia Universidad Católica de Chile, Santiago, Región Metropolitana, Chile

 
Intra abdominal fat depots has previously been associated with liver fibrosis on non alcoholic fatty liver disease (NAFLD) patients. In this study we evaluated different imaging biomarkers associated with liver fibrosis/cirrhosis in type 2 diabetes mellitus (DM2) patients. For this, we evaluated volumetric quantification of visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT) using MR; volumetric quantification of abdominal fat depots with anthropometric indexes, like Body Mass Index (BMI) and Waist Circumference (WC); Transient Elastography (TrE) using Acoustic Radiation Force Impulse (ARFI), and clinical diagnosis based on different MR images. Results suggest that DM2 patients with increasing ARFI and largest amount of VAT might be associated with progression of liver fibrosis.

 
4098.   70 Evaluation of hepatic lipid in high fat diet induced obese rats by in-vivo MRS and LC-MS techniques
Jadegoud Yaligar1, Venkatesh Gopalan1, Shui Guanghou2, Lam B D Jenny2, Tai E Shyong3, Markus R Wenk2, and S. Sendhil Velan1
1Laboratory of Molecular Imaging, Singapore Bioimaging Consortium, Singapore, Singapore, 2Department of Biological Sciences, National University of Singapore, Singapore, Singapore, 3Department of Medicine, School of Medicine, National University of Singapore, Singapore, Singapore

 
Accumulation of Fatty acids and triglycerides in hepatocytes leads to metabolic syndrome. In the current study we have investigated the hepatic fat including saturated and unsaturation in high fat induced obese and control animals. In addition we have developed advanced LC/MS techniques for validating the MRS results. Both MRS and LC/MS results were comparable and increases the prior knowledge for MRS quantification. Total hepatic fat content estimated by MRS and LC/MS in high fat animals was significantly higher and unsaturation index was significantly lower compared to its control group. The combined approach of MRS and LC/MS techniques permits the comprehensive analysis of hepatic lipid components.

 
4099.   71 Obesity-Related Variations in T2* and Fat Content of Murine Brown and White Adipose Tissues by Chemical-Shift MRI
Houchun Harry Hu1,2, Catherine D. G. Hines3, and Scott B. Reeder4
1Radiology, Children's Hospital of Los Angeles, University of Southern California, Los Angeles, California, United States, 2Electrical Engineering, University of Southern California, Los Angeles, California, United States, 3Merck Research Laboratories, West Point, Pennsylvania, United States,4Radiology, Medical Physics, Biomedical Engineering, and Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States

 
We utilized a chemical-shift water-fat MRI technique to characterize T2* and proton density fat-fraction (PDFF) differences between interscapular brown (BAT) and gonadal white (WAT) adipose tissues in lean and genetically obese mice. Lean mice (n=6) and two groups of obese ob/ob mice placed on four-week (n=6) and eight-week (n=8) diets were studied. Comparing within each group, BAT T2* and PDFFs were consistently lower than WAT (p<0.001). Comparing across groups, longer BAT T2* and greater BAT PDFFs were measured in older and more obese ob/ob mice than lean mice (p<0.001). Collectively, these observations reflect the lean group’s greater BAT thermogenic activity.

 
4100.   72 Correlation of fat signal from Dixon imaging with 18F-FDG accumulation using an integrated PET/MR system
Steffen Renisch1, Susanne Heinzer2, Holger Eggers1, Osman Ratib3, and Peter Börnert1
1Philips Research Europe, Hamburg, Germany, 2Philips AG Healthcare, Zurich, Switzerland, 3Nuclear Medicine, University Hospital of Geneva, Geneva, Switzerland

 
The combination of PET and MR can increase the diagnostic value of both modalities due to the additional information becoming available. PET measures the spatial distribution of an appropriate tracer while MR offers a huge variety of soft tissue contrasts, like T1, T2 , diffusion and water and fat. For the latter Dixon imaging has been developed yielding excellent fat suppression and also clinically useful information about the fat distribution and its content in specific tissues [1]. Current literature shows [2] that there generally is limited 18F- Deoxyglucose (FDG) and 18F-Choline (FCH) [4] uptake in tissue with a high fat content. Therefore, the information about the fat content might be very useful in PET image interpretation. Integrated PET/MR platforms, now becoming available, enable the combination of anatomical information and information about the fat content from the Dixon images with the functional information stemming from the 18F-FDG- and 18FCH PET due to the intrinsic registration of PET and MR data. In this patient study, we demonstrate a correlation between fat void regions and FDG/FCH uptake. This information may serve for partial volume correction in PET reconstruction and permits further characterization of disease.
 
Electronic Poster Session - Body

Body DWI
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  16:00 - 17:00

  Computer #  
4101.   73 Investigation on the correlation between the DWI apparent diffusion coefficient and the FDG-PET/CT standardized uptake value in patients with lymphoma
Thomas Kwee1, Henriëtte Quarles van Ufford1, Malou Vermoolen1, Frederik Beek1, Rob Fijnheer2, Willem Mali1, John de Klerk3, and Rutger-Jan Nievelstein1
1Radiology, UMC Utrecht, Utrecht, Netherlands, 2Hematology, Meander MC, Amersfoort, Netherlands, 3Nuclear Medicine, Meander MC, Amersfoort, Netherlands

 
This study aimed to assess the correlation between the ADC and the FDG-PET/CT SUV in lymphoma. Although no correlation was found between the ADCmean and the SUVmax, there was a trend towards a mild negative correlation between the ADCmin and the SUVmax. This can be explained by the fact that the ADCmin better represents the area of lowest cellular density than the ADCmean; thus, lymphomas with higher cellularity tend to have higher glucose metabolism. Further studies are required to investigate the complementary roles of these DWI and FDG-PET/CT metrics with respect to tumor grading and assessment of response to therapy.

 
4102.   74 Segmented total disease volume and associated apparent diffusion coefficient on whole body diffusion-weighted MRI show good interobserver agreement
Matthew D Blackledge1, Nina Tunariu1, David J Collins1, Martin O Leach1, and Dow-Mu Koh1
1CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden Hospital, Sutton, United Kingdom

 
Whole body DWI (WBDWI) allows the duo quantification of the total diseased diffusion volume and associated global mean/ median apparent diffusion coefficient (ADC), which are promising response biomarkers. However, the interobserver agreement of this approach has not been previously established. We found excellent interobserver agreement for segmenting total diseased diffusion volume on WBDWI and very good interobserver agreement for global median ADC values. These quantitative indices are robust and could be investigated more widely in future clinical trials, especially for the assessment of metastatic bone disease.

 
4103.   75 Preoperative T staging of urinary bladder: Diagnostic performance of diffusion-weighted MR imaging at 3.0 T
Yoshimitsu Ohgiya1, Jumpei Suyama1, Syouei Sai1, Makoto Saiki1, Takashi Hashizume1, Noritaka Seino1, Masanori Hirose1, and Takehiko Gokan1
1Showa University School of Medicine, Tokyo, Japan

 
The purpose of this study was to evaluate the ability of DW MR imaging at 3.0T for diagnosing T stage in bladder cancer. Sensitivity and accuracy for differentiating T1 tumors from T2 to T4 tumors and Overall accuracy for diagnosing tumor stage obtained by using T2-weighted plus DW images were significantly better than those obtained by using T2-weighted images alone (P = 0.02). DW images at 3T can provide useful information for evaluating the T stage of bladder cancer, particularly in differentiating T1 or lower tumors from T2 or higher tumors.

 
4104.   76 Can diffusion-weighted MRI predict pathological complete response after neoadjuvant chemoradiation therapy in rectal cancer patients?
Giuseppe Petralia1, Josep Garcia-Bennett2, Luke Bonello3, Stefano Viotti3, Paul Summers1, Maria Giulia Zampino1, Maria Cristina Leonardi1, and Massimo Bellomi1,3
1European Institute of Oncology, Milan, Italy, 2Hospital St Joan de Reus, Reus, Spain, 3University of Milan School of Radiology, Milan, Italy

 
Better long-term outcome is reported for rectal cancer patients with pathological complete response (pCR) after neoadjuvant chemoradiation therapy (NACRT). Minimalist approaches are a reasonable alternative to radical surgery in such patients, with equivalent outcomes. T2-weighted MRI is not predictive of pCR. Diffusion-weighted MRI (DW-MRI) detects abnormalities in tissues and there is preliminary evidence that the apparent diffusion coefficient (ADC) may predict response to therapy. Fifty-nine patients underwent DW-MRI before and after NACRT, and ADC was calculated for tumour. ADC values before and after NACRT and their changes following treatment did not predict the pCR after NACRT in rectal cancer patients.

 
4105.   77 Histologically-validated Bladder Cancer Staging with Magnetic Resonance Imaging at 3T
Huyen Thanh Nguyen1,2, Guang Jia1, Zarine K Shah1, Kamal S Pohar3, Amir Mortazavi4, Debra Zynger5, and Michael V Knopp1
1Wright Center of Innovation in Biomedical Imaging, Department of Radiology, The Ohio State University, Columbus, OH, United States, 2Biophysics Program, The Ohio State University, Columbus, OH, United States, 3Department of Urology, The Ohio State University, Columbus, OH, United States,4Department of Internal Medicine, The Ohio State University, Columbus, OH, United States, 5Department of Pathology, The Ohio State University, Columbus, OH, United States

 
Purpose: to investigate the capability of 3T MRI in accurately staging bladder cancer. Methods: all scans were performed with T2w before DCE MRI. With defined staging criteria, a radiologist staged bladder tumors by using T2w images, and then DCE data. Results: staging of T2/lower by using T2w images and DCE data had high sensitivities (80% and 90%), specificities (82% and 73%), and accuracies (81% and 81%). The overall accuracy of staging with T2w and DCE MRI were 71% and 81%, respectively. Conclusion: 3T MRI with the potential to accurately stage bladder cancer can make a major impact on the patient outcome of cystectomy.

 
4106.   78 Post-hoc spatial registration of multiple b-value diffusion weighted images improves test-retest reliability of ADC measurements in solid tumors in the body
Alexandre Coimbra1, Jill Fredrickson1, Roel Funke1, Daniel Chen1, and Alex de Crespigny1
1Oncology Early Clinical Development, Genentech, Inc., South San Francisco, CA, United States

 
Accurate assessment of tissue apparent diffusion coefficient (ADC) requires acquisition and analysis of multiple b-value diffusion weighted images (DWI). One important source of variability in this ADC assessment is spatial misregistration across the multiple DWIs, particularly those at high b-values. The current work describes a simple post-hoc automated approach for spatial registration of multiple b-value DWIs. Applied to test-retest data set from a cohort of cancer patients, this approach enhanced repeatability of ADC measurements.

 
4107.   79 Whole-body MRI with diffusion-weighted sequences for the follow-up of stage III melanoma patients
Giuseppe Petralia1, Sarah Alessi1, Josep Garcia-Bennett2, Paul Summers1, Sara Raimondi1, Roberto Di Filippi1, Luke Bonello3, and Massimo Bellomi1,3
1European Institute of Oncology, Milan, Italy, 2Hospital St Joan de Reus, Reus, Spain, 3School of Radiology University of Milan, Milan, Italy

 
Surgery is the best option for patients with advanced melanoma, who would benefit from early detection of metastases. Whole-body magnetic resonance imaging (WB-MRI) with diffusion weighted sequences was feasible on advanced melanoma patients. It was performed with low dose computed tomography (CT) of the lung every three months, allowing for a 30 fold reduction of radiation exposure, when compared to the radiation dose that the same patients would receive if followed-up with whole-body CT. The following overall sensitivity (93%), specificity (89%), negative predictive value (99%), positive predictive value (52%) and diagnostic accuracy (90%) were observed for the detection of metastases.

 
4108.   80 Impact of the noise model on intra-voxel incoherent motion (IVIM) parameter estimates in abdominal DW-MRI
Moti Freiman1, Jeannette M Perez-Rossello1, Michael J Callahan1, Mark Bittman1, Stephan D Voss1, Robert V Mulkern1, and Simon K Warfield1
1Radiology, Children's Hospital Boston/Harvard Medical School, Boston, MA, United States

 
Numerical schemes commonly used to estimate the Intra-voxel incoherent motion (IVIM) model parameters from DW-MRI approximate Rician noise of the signal intensities with a Gaussian noise model which may induce bias in IVIM model parameters estimation. We developed a maximum likelihood estimator (MLR) that accounts for the Rician distributed noise; and assessed the impact of the noise model and numerical algorithm used to estimate IVIM model parameters. In vivo measurements of the abdominal organs’ IVIM model parameters values of 15 pediatric subjects show significant discrepancies of up to ~30% between MLR and segmented least squares estimator, and smaller, but yet significant discrepancies of ~2%-3% between the non-linear least squares and MLR estimators.

 
4109.   81 Distinguishing restricted diffusion and flow using pulsed and oscillating diffusion gradients at 1.5 T
D J McHugh1,2, P L Hubbard1,2, S Zhao1,2, G J Parker1,2, and J H Naish1,2
1Imaging Sciences and Biomedical Engineering, University of Manchester, Manchester, United Kingdom, 2The University of Manchester Biomedical Imaging Institute, United Kingdom

 
We present preliminary results of using pulsed and oscillating diffusion gradients at 1.5 T to measure the apparent diffusion coefficient (ADC) and perfusion-sensitive diffusivity as a function of effective diffusion time in the human liver. Results show an increase in ADC as shorter diffusion times are probed, providing evidence of restricted diffusion, as well as a decrease in the perfusion-sensitive diffusivity at shorter diffusion times. This indicates the feasibility of using the time-dependent diffusivity to distinguish between restricted diffusion and flow in humans, and the potential for using oscillating diffusion gradients at low field strength to reach shorter diffusion times.

 
4110.   82 Repeatability of Abdominal Diffusion Weighted MRI: A Phantom & Volunteer Study
Marc Eric Miquel1,2, Andrew David Scott1, Redha Boubertakh1, Niall Dominic MacDougall1, Nishat Bharwani3, and Andrea G Rockall4
1Clinical Physics, Barts and the London NHS Trust, London, United Kingdom, 2Barts and the London Cardiovascular Biomedical Research Unit, Queen Mary University of London, London, England, United Kingdom, 3Radiology Department, Imperial College Healthcare NHS Trust, London, United Kingdom,4Department of Imaging, Barts and the London NHS Trust, London, United Kingdom

 
DW-MRI is potentially a useful cancer biomarker and apparent diffusion coefficient (ADC) could be used to monitor treatment. However, repeatability studies are still limited. We investigated the in-vitro and in-vivo repeatability of a free-breathing abdominal DWI-sequence. The in-vitro coefficient of variation was less than 1.5%. In-vivo, the coefficients of reproducibility were kidney 20%, gallbladder 21%, liver 24.7% and spleen 28.0% when taking into account small regions of interest.. For large volumes of interest, values fall to 7.7, 6.4, 8.6 and 9.6% respectively. If all organs are considered indiscriminately the values are 23.1% for small regions and 7.9% for large volumes.

 
4111.   83 A fast and simple post-processing procedure for the correction of mis-registration between sequentially acquired stations in whole-body diffusion weighted MRI
Matthew D Blackledge1, Dow-Mu Koh1, Matthew R Orton1, David J Collins1, and Martin O Leach1
1CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden Hospital, Sutton, United Kingdom

 
A simple post-processing algorithm is described to correct for station mis-alignment and intra-station discontinuities in signal intensity in whole-body diffusion weighted imaging. The technique is demonstrated on a volunteer study and on a patient data set. A significant improvement in image quality compared to currently available correction methods is observed in both cases.

 
4112.   84 The influence of model used to fit DW-MRI data on Apparent Diffusion Coefficient estimates and their reproducibility in normal tissues
Nina Tunariu1, David J Collins1, Matthew Orton1, James A d'Arcy1, Veronica A Morgan1, Sharon L Giles1, and Nandita M deSouza1
1CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden Hospital, Sutton, London, United Kingdom

 
Diffusion Weighted MRI is considered a potential biomarker for anticancer therapy response. The literature suggests that assumption of a simple exponential relationship between signal attenuation and b value for ADC calculation may be too simplistic and that using more complicated mathematical models which account for the non-monoexponential behaviour of the diffusion signal attenuation in tissues results in a better data fitting and potentially less variable ADC estimates. The purpose of this study was to evaluate the influence of the mathematical model used to fit the DW-MRI data on the ADC values and their reproducibility.

 
4113.   85 Combining Slice Dependent Center Frequency Adjustment and High Order Eddy Current Correction for Improved Multistation Diffusion Weighted Imaging
Dan Xu1, Gaohong Wu2, Jun Xie2, and Kenichi Kanda2
1Applied Science Lab, GE Healthcare, Waukesha, WI, United States, 2MR Engineering, GE Healthcare, Waukesha, WI, United States

 
B0 field offset and eddy current induced image distortions often seen in diffusion weighted echo planar imaging can be worsened in multistation settings (e.g., whole body imaging), where the unmatched distortions at station boundaries can create sharp discontinuities, largely degrading image quality. We propose to use a combined high order eddy current and slice dependent center frequency correction to reduce image distortion and bulk shift. A 2-station phantom study shows that the proposed method is capable of minimizing station boundary discontinuities and slice shift trend.

 
4114.   86 Fat suppression for continuously moving table whole-body diffusion-weighted imaging using the gradient reversal technique
Yeji Han1, Yoojin Lee1, ChangHyun Oh1, and HyunWook Park1
1Department of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea

 
Although whole-body DWI (wbDWI) is generally performed using the multistation approach, a recent work has demonstrated that the continuously moving table (CMT) approach produces images with more homogeneity in terms of temporal and spatial discontinuities. In the CMT-wbDWI, short tau inversion recovery (STIR) was used to suppress fat but remains of the fat signal could still be observed in the images. In this abstract, we propose to use the gradient reversal (GR) algorithm for CMT-wbDWI and analyze how the GR algorithm can improve the fat suppression results of the CMT sequences.

 
4115.   87 Optimistaion of b-value distribution in biexponential modelling
Peter Gibbs1, Martin D Pickles1, and Lindsay W Turnbull1
1University of Hull, Hull, East Yorkshire, United Kingdom

 
Bi-exponential fitting of DWI data to account for microperfusion effects is becoming increasingly prevalent both in the brain and other organs. Increased sampling of low b-values to adequately define the bi-exponential curve appears necessary. However, little work has attempted to assess the optimum b-value sampling strategy. Using synthetic data this study demonstrates that a highly non-linear sampling scheme is necessary for tissues with a rapid and large perfusive component and that high SNR data is required to appropriately define tissues with a small perfusive fraction.

 
4116.   88 Whole-body DWI: reduction of scan time using direct coronal acquisition
Hayato Takano1, Tomohiko Horie1, Isao Muro1, Nao Kajihara1, Yutaka Imai1, Makoto Obara2, Tetsuo Ogino2, Akira Suwa2, Marc van Cauteren2, Gwenael Herigault2, Thomas Kwee3, and Taro Takahara4
1Radiology, Tokai University School of Medicine, Isehara, Kanagawa, Japan, 2Philips Healthcare, 3University Medical Center Utrecht, 4Tokai University School of Engineering, Hiratsuka, Kanagawa, Japan

 

4117.   89 Smart Combination: A Technique for Reducing Cardiac Motion Induced Signal Loss in Diffusion-Weighted Liver Imaging
ZHIQIANG LI1, Zhenghui Zhang1, Gaohong Wu1, and Xiaoli Zhao1
1MR Engineering, GE Healthcare, Waukesha, WI, United States

 
One issue with single-shot diffusion-weighted EPI image of the liver is the signal loss in regions proximal to the heart due to cardiac motion. Various techniques in both data acquisition and post-processing have been proposed to mitigate this issue. In this work we present a new post-processing strategy to reduce the signal loss by combining the individual diffusion-weighted images with appropriate weights. In-vivo results demonstrated the feasibility.

 
4118.   90 Motion correction of diffusion-weighted imaging of the liver: use of velocity-compensated diffusion gradients combined with tetrahedral gradients
Masanori Ozaki1,2, Yusuke Inoue3, Tosiaki Miyati2, Hirofumi Hata4, Shinya Mizukami5, Shotaro Komi4, Keiji Matsunaga3, Reiko Woodhams3, and Shinichi Kan3
1School of Allied Health Sciences, Kitasato University, Sagamihara, Kanagawa, Japan, 2Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa, Japan, 3Department of Diagnostic Radiology, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan, 4Department of Radiology, Kitasato University Hospital, Kanagawa, Japan, 5Department of Radiology, Kitasato University Hospital, Sagamihara, Kanagawa, Japan

 
In diffusion-weighted imaging (DWI), the artificial elevation of the apparent diffusion coefficient (ADC) of the liver parenchyma occurs due to signal loss caused by cardiac motion. This effect can be reduced by using a velocity-compensated (VC) -DWI sequence. However, a limitation of the VC-DWI sequence is that it provides a lower SNR than a conventional DWI sequence. Tetrahedral gradients can be used to obtain higher SNRs than conventional orthogonal gradients. The purpose of our study was to evaluate the efficacy of a VC-DWI sequence combined with tetrahedral gradients (t-VC-DWI) in liver parenchyma.

 
4119.   91 Investigation of Liver Diffusion Kurtosis Imaging and Perfusion Effect
Yuriko Suzuki1, and Marc Van Cauteren1
1MR Clinical Science, Philips Electronics Japan, Minato-ku, Tokyo, Japan

 
Diffusion Kurtosis Imaging (DKI) is a method to study the deviation of water diffusion from Gaussian distribution, which has been applied mostly to study neural tissue characterization and brain diseases. The aim of study was to investigate how the selection of maximum and minimum b-value affected the liver DKI analysis, and to assess the feasibility of liver DKI in reasonable scan time. Our study has shown relatively good results even with maximum b-value of 1,500 s/mm2, which is smaller than one used in the brain, and would make easier to apply clinical cases.

 
4120.   92 A Preliminary Study Evaluating the Functional Diffusion Map for Early Detection of TACE Treatment Response in Patients with Liver Carcinoma
Hongyan Chen1, Yufang Chen1, He Wang2, Yongbo Yang1, Guang Cao2, and Xu Yan3
1Eastern Hepatobiliary Surgery Hospital, Shanghai, Shanghai, China, 2Applied Science Lab, GE Healthcare, Shanghai, Shanghai, China, 3East China Normal University, Shanghai, Shanghai, China

 
This study is a preliminary trial of evaluating treatment response of liver carcinoma based on FDM. 20 patients with liver carcinoma were enrolled in our research. Our results shows the percentage of the increased ADC region and changed ADC region can be robust imaging biomarkers for detection of treatment response in patients with liver carcinoma.

 
4121.   93 Optimization of Diffusion-Weighted Imaging for the Liver MRI at 3T: Usefulness for the Detection of Hepatocellular Carcinoma
Yukihisa Takayama1, Akihiro Nishie1, Yoshiki Asayama1, Kousei Ishigami1, Daisuke Kakihara2, Yasuhiro Ushijima1, Nobuhiro Fujita1, Atsushi Takemura3, Makoto Obara3, and Hiroshi Honda1
1Department of Clinical Radiology, Kyushu University, Graduate School of Medical Sciences, Fukuoka, Fukuoka, Japan, 2Department of Molecular Imaging & Diagnosis, Kyushu University, Graduate School of Medical Sciences, Fukuoka, Fukuoka, Japan, 3Philips Electronics Japan, Tokyo, Tokyo, Japan

 
Our proposed optimized diffusion-weighted imaging (DWI) can not only improve the image quality and spacial resolution, but also reduce chemical shift and susceptibility artifacts. In this study, we evaluated the utility of our proposed optimized DWI of liver magnetic resonance imaging. It can offer better diagnostic performance without reducing the signal-to-noise ratio of the normal liver parenchyma and lesion-to-non-lesion contrast-to-noise ratio with the conventional DWI which is widely used in the clinical practice. We suggest that our proposed optimized DWI should be advantageous for liver MRI to detect hepatocellular carcinoma.

 
4122.   94 Change of apparent diffusion coefficient in hepatocellular carcinoma treated by concurrent chemotherapy and radiation therapy: Correlation with change in size, 2-dimentional measurement vs 3-dimentional measurement
kyung Ah Kim1, Mi-Suk Park1, In-Seong Kim2, Peter Gall3, Myeong-Jin Kim1, and Ki Whang Kim1
1Radiology, Yonsei University College of Medicine, Seoul, Seoul, Korea, 2MR Clinical Science, Siemens Healthcare, Korea, 3Oncology & Interventions, Siemens AG

 

4123.   95 Evaluation oEvaluation of hepatic fibrosis at Diffusion weighted liver MRI with intravoxel incoherent motion model
Jeong-Hee Yoon1, Jeong Min Lee2, Olivier de Andre3, Mun young Paek3, MiHye Yu2, Joon Ku Han2, and Byung Ihn Choi2
1Seoul National University Hospital, Seoul, Seoul, Korea, 2Seoul National University Hospital, 3Siemens Healthcare

 
Liver diffusion MR with intravoxel incoherent motion (IVIM) was performed using multiple b-values (b=0, 25, 50, 75, 100, 200, 500, 800) in 119 patients from June 2010 to May 2011. During the period, 29 patients underwent liver MR twice, and 9 out of 119 patients underwent liver diffusion MR in free breathing (FB) and respiratory triggering (RT). After obtaining IVIM derived parameters, we assess the difference between parameters in FB and those in RT. Also we assessed the reproducibility of IVIM derived parameters. Finally IVIM derived parameters were compared in liver cirrhosis group and non-cirrhotic group.

 
4124.   96 Incorporating Diffusion Techniques into Whole body MRI
Raj Attariwala1, and Wayne Picker1
1AIM Medical Imaging, Vancouver, BC, Canada

 
An overview of the theory of diffusion weighted imaging, and adding this powerful sequence routinely into whole body MRI imaging for improved lesion localization and characterization will be reviewed. Incorporation of diffusion images and critical parameters for ADC calculation as well as interpretation pearls and pitfalls will be presented from a facility that has performed over 1000 diffusion studies.
 
Electronic Poster Session - Body

Female Pelvis & Fetal
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  17:00 - 18:00

  Computer #  
4125.   73 Diffusion-weighted Echo-planar 3 T MRI and Minimum ADC Mapping in the Differential Diagnosis of Ovarian Masses with Solid Components: Comparison with Mean ADC mapping
Tomohiro Namimoto1, Toshinori Hirai1, Kosuke Morita1, Daisuke Utsunomiya1, Seitaro Oda1, Fumi Sakaguchi1, and Yasuyuki Yamashita1
1Diagnostic Radiology, Kumamoto University, Kumamoto, Kumamoto, Japan

 
The purpose of our study is to determine the accuracy of DW imaging in the characterization of ovarian masses with solid components and to clarify the relationship between ADCmean and ADCmin with solid components of the ovarian tumors in patients undergoing pelvic 3T MR imaging. In conclusion, the ADCmean and ADCmin of malignant ovarian masses with solid components were significantly lower than those of other benign- and border line masses. ADCmin was better than ADCmean for characterization of ovarian masses with solid components. However, it may be occasionally difficult to differentiate benign and malignant masses only on the basis of DW imaging.

 
4126.   74 Multiparametric Approach to Diagnose Ovarian Lesions Preoperatively: Combination of ADC and MRS
Peter Stanwell1, Jonathan Carter2, Peter Russell3, and Carolyn Mountford4
1Faculty of Health, University of Newcastle, Callaghan, NSW, Australia, 2Royal Prince Alfred Hospital, Sydney Gynaecological Oncology Group, Camperdown, NSW, Australia, 3Sydney Gynaecological Oncology Group, Royal Prince Alfred Hospital, Camperdown, NSW, Australia, 4Centre for MR in Health, University of Newcastle, Callaghan, NSW, Australia

 
Single voxel spectroscopy (SVS) and apparent diffusion coefficients (ADC) were measured in 10 patients with clinical suspicion of ovarian cancer. Results from SVS and ADC were compared with histopathology obtained following surgery. Both techniques produced statistically significant differences for distinguishing between benign and malignant ovarian neoplasms. Further studies with larger patient numbers are now needed to validate this approach.

 
4127.   75 Recurrent Ovarian Cancer: Comparison of Diffusion-Weighted Imaging and T2-Weighted Imaging in Accurately Localizing Tumor Recurrence
Chunmei Li1, Min Chen2, Luxian Zhang2, Chen Zhang2, and Cheng Zhou2
1Beijing Hospital, Beijing, Beijing, China, 2Beijing Hospital

 
Purpose: To compare accuracy in the detection of recurrent ovarian cancer with DWI and T2WI on 1.5 T MR and determine whether imaging information can predict survival. Methods: Axial T2WI and DWI of 21 women were independently analyzed by two radiologists. Tumor presence, number of lesions, size and minimal ADC were recorded for patient and region. Receiver operator characteristic curves were generated. Results: Readers¡¯ AUCs in detection of recurrence were higher for DWI than for T2WI. Size, number ADC value were significantly associated with poor survival. Conclusion: DWI may improve accuracy in the detection and localization of recurrent ovarian cancer on 1.5 T MR. Some imaging findings can be used to predict survival.

 
4128.   76 Proton MR spectroscopy of Ovarian Tumors at 3T: Differentiation of Benign and Malignant Solid Components of Ovarian Tumors
Mayumi Takeuchi1, Kenji Matsuzaki1, and Masafumi Harada1
1Department of Radiology, University of Tokushima, Tokushima, Tokushima, Japan

 
We evaluated ovarian solid, or complex solid and cystic masses by MRS at 3T. The choline concentration in 21 malignant tumors with predominantly solid nature (9.47 +/- 4.66 mM) was significantly higher than that in 11 benign lesions (5.48+/-4.77 mM) (p<0.05). Using a cut off value of 6 mM for malignant lesions had a sensitivity of 81%, specificity of 73%, PPV of 85%, and NPV of 67%. MRS can provide helpful information in distinguishing benign and malignant ovarian tumors, however, malignant tumors showing solid and cystic nature or containing necrotic areas tended to show lower choline concentration.

 
4129.   77 1H Magnetic Resonance Spectroscopy(MRS) of Endometrial Carcinoma and Normal Endometrium of Childbearing Women in Different Menstrual Cycle
Xiaoduo Yu1, Yan Chen1, Meng Lin1, Han Ouyang1, and Chunwu Zhou1
1Department of Diagnostic Radiology, Cancer Hospital & Institute, Chinese Academy of Medical Sciences & Peking Union Medical College, beijing, beijing, China

 
MRS could provide insights into the metabolism of uterus tumor at molecular level, and has the utility to evaluate the state of endometrium in physiology and pathology quantitatively. Difference among choline peak value of endometrial carcinoma and normal endometrium of childbearing women in different menstrual cycle would be helpful to diagnose the endometrial carcinoma and optimization of exam time.

 
4130.   78 Clinical significance of lipid peak in in-vivo 1H-MR spectroscopy of uterine sarcomas at 3T
Mayumi Takeuchi1, Kenji Matsuzaki1, and Masafumi Harada1
1Department of Radiology, University of Tokushima, Tokushima, Tokushima, Japan

 
We evaluated 14 uterine sarcomas and 24 benign myometrial lesions by 1H-MR spectroscopy at 3T. High lipid peaks were observed in 12 of 14 sarcomas, whereas in none of benign lesions except for one lipoleiomyoma. The choline peaks were observed in 12 of 14 sarcomas, whereas in all 24 benign lesions. However massive necrosis in sarcomas may decrease the choline peak, the presence of high lipid peak may suggest their malignant nature. We conclude that high lipid peak in uterine mass without fatty component is suggestive for sarcoma, whether the choline peak is present or not.

 
4131.   79 Combined diffusion-weighted magnetic resonance imaging and MR lymphography reliably detect and evaluate sentinel lymph node in cervical cancer
Zhengyang Zhou1, Haiping Yu1, Bin Zhu1, Ying Hong2, and Jiang Fang2
1Radiology, Affiliated Drum Tower Hospital,School of Medicine,Nanjing University, Nanjing, Jiangsu, China, 2Gynaecology, Affiliated Drum Tower Hospital,School of Medicine,Nanjing University, Nanjing, Jiangsu, China

 
To evaluate whether combined DWI and MR lymphography (MRLG) reliably detect and evaluate sentinel lymph nodes (SLNS) metastasis in cervical cancer, 38 patients were preoperatively underwent interstitial MRLG with Omniscan after completed the conventional MRI and DWI examinations at a b-value of 1000 s/mm2. Blue dye SLN biopsy was performed on all patients. We found that compared with only MRLG without DWI versus histopathology, the combined MRLG and DWI approach revealed a higher diagnostic accuracy. Obviously, the combination of DWI and MRLG was useful in detecting the SLNs and in improving the diagnostic accuracy of SLN metastases in cervical cancer.

 
4132.   80 Pretreatment diffusion-weighted imaging at 3T for overall survival prediction in chemoradiotherapy treated advanced cervical cancer patients.
Martine I Dujardin1, Martin D Pickles1, Abdullah Aldosary2, Peter Gibbs1, and Lindsay W Turnbull1
1Centre for MR Investigations, University of Hull in association with Hull York Medical School, Hull, United Kingdom, 2King Fahad Medical City, Riyadh, Saudi Arabia

 
This study investigates the ability of pretreatment ADCs acquired at 3T to predict overall survival (OS) in chemoradiotherapy in advanced cervical cancer patients (N=26). The use of group median (p=0.16 ) or 75th percentile of group ADC values (p=0.86) as a dichotomizing value did not result in a significant difference for survival between a high and low ADC group. Kaplan-Meier analysis showed that the survival rate in the low-ADC group was significantly worse than that in the high-ADC value group (p=0.042) when groups were dichotomized on the basis of the 25th percentile (0.85×10-3 mm2/s) of group pretreatment ADC values.

 
4133.   81 B0-correction and k-means clustering for accurate and automatic identification of regions with reduced apparent diffusion coefficient (ADC) in advanced cervical cancer at the time of brachytherapy
Søren Haack1, Erik Morre Pedersen2, Mads Sloth Vinding3, Jesper Folsted Kallehauge4, Jacob Christian Lindegaard5, Kari Tanderup5, and Sune Nørhøj Jespersen6
1Dept. of Clinical Engineering, Aarhus University Hospital, Aarhus, Denmark, 2Dept. of Radiology, Aarhus University Hospital, Aarhus, Denmark, 3inSpin, iNANO, Aarhus University, Aarhus, Denmark, 4Dept. of Medical Physics, Aarhus University Hospital, Aarhus, Denmark, 5Dept. of Oncology, Aarhus University Hospital, Aarhus, Denmark, 6CFIN/Mindlab, Aarhus University, Aarhus, Denmark

 
Diffusion weighted MRI has shown great potential in diagnostic cancer imaging and may also have value for monitoring tumor response during radiotherapy. Uncertainties due to geometric distortions caused by B0-inhomogeneity and tumor delineation are major obstacles for implementing DWI for use in dose planning of radiotherapy. This study evaluates the use of k-means clustering for automatic user independent delineation of regions with reduced apparent diffusion coefficient (ADC) and the value of B0-correction of DW-MRI for reduction of geometrical distortions during dose planning of brachytherapy of advanced cervical cancer.

 
4134.   82 Susceptibility-weighted imaging for the evaluation of extra-ovarian endometriosis
Mayumi Takeuchi1, Kenji Matsuzaki1, and Masafumi Harada1
1Department of Radiology, University of Tokushima, Tokushima, Tokushima, Japan

 
We evaluated 14 extra-ovarian endometriosis by susceptibility-weighted imaging (SWI). In 12 solid tumor-like masses punctate or curved linear signal voids on SWI were observed in all lesions, whereas high intensity hemorrhagic foci on fat-saturated T1WI were observed in 7 of 12 lesions. In 2 cystic lesions curved linear signal voids along the cyst wall on SWI were observed, whereas high intensity hemorrhagic foci were not revealed on fat-saturated T1WI. We conclude that SWI is more sensitive for endometriosis-associated hemorrhagic change than fat-saturated T1WI, and may contribute to the diagnosis of extra-ovarian endometriosis.

 
4135.   83 Comprehensive Review: Various Clinical and Radiologic Manifestations of Endometriosis
Sung Bin Park1
1Radiology, Cheil General Hospital & Women¡¯s Healthcare Center, Kwandong University College of Medicine, Seoul, Korea

 
The imaging characteristics of endometriosis vary widely, with masses ranging from cystic to solid and complex, which depend in the hormonal response of the ectopic tissue during the menstrual cycle. MRI is important for identification and characterization of endometriosis.

 
4136.   84 Imaging Features Pregnancy Associated Maternal Disorder
Sung Bin Park1
1Radiology, Cheil General Hospital & Women¡¯s Healthcare Center, Kwandong University College of Medicine, Seoul, Korea

 
Pregnancy associated maternal disorders are broad spectrum. It is important to know this pregnancy associated maternal disorders because they may influence the fetus as well as the pregnant woman.

 
4137.   85 Clinical evaluation of a novel method, linear radial k-trajectory THRIVE (Liner-THRIVE) for pelvis image: compared among THRIVE, e-THRIVE and Liner-THRIVE
Takashige Yoshida1, Yasutomo Katsumata2, Yuki Furukawa1, Naoki Watanbe1, Yukio Kato1, Nobuo Kawauchi1, and Tetsuro Shirai3
1Radioligy, Tokyo Metropolitan Police Hospital, Tokyo, Japan, 2Technical&Clinical Support, Philips Electronics Japan, Ltd., Tokyo, Japan, 3Tokyo Metropolitan Police Hospital, Tokyo, Japan

 
Three-Dimensional gradient echo sequence named THRIVE and e-THRIVE needs better contrast and lower artifact for pelvis image with Contrast enhacement. Adopted centric-radial k-space tarajectory as THRIVE result in good contrast,but blurring is outstanding. And adopted linear k-space trajectory combined partial Fourier transformation as e-THRIVE improved blurring of THRIVE, but truncation influences image using e-THIRVE.Furthermore,adopted linear radial k-space trajectory as Liner-THRIVE was able to improve disadvantage of THRIVE and e-THRIVE.

 
4138.   86 Clinical utility of 3D T2 SPACE pulse sequence in MR imaging of female pelvis
RAJ MOHAN PASPULATI1, Kianoush.Ansari Gilani1, and GURUPREET SANDHU2
1RADIOLOGY, UNIVERSITY HOSPITALS, CASE WESTERN RESERVE UNIVERSITY, CLEVELAND, OHIO, United States, 2Radiology, University Hospitals, Case Western Reserve university, Cleveland, Ohio, United States

 
MR imaging of the female pelvis is performed routinely for diagnosis of various benign uterine or adnexal pathology as well as for staging of gynecologic malignancies. Acquiring high resolution T2 weighted images in 3 orthogonal planes is the gold standard for evaluation of the complex pelvic anatomy and pathology. Traditional T2 weighted imaging includes acquiring high resolution 2D T2 Turbo spin echo (TSE) in 3 planes which is time consuming and image plane has to be prescribed according to the orientation of the uterus. Improper orientation of the imaging plane by the technologist results in loss of crucial anatomical information. Acquiring high resolution 3DT2 weighted images in a single plane significantly reduces scan time and is also less technologist dependent for selecting a proper imaging plane. Imaging technique, clinical utility, advantages and disadvantages of this T2 weighted imaging technique will be illustrated in this exhibit using several examples of benign and malignant pelvic pathology of the female pelvis.

 
4139.   87 Fetal Growth in Diabetic Pregnancies
Devasuda Anblagan1, Ruta Deshpande2, Nia W Jones2, Alain Pitiot3, Carolyn Costigan1, Kirsty Allcock4, Nick Raine Fenning5, Lopa Leach6, George Bugg2, Peter Mansell2, and Penny A Gowland1
1Sir Peter Mansfield Magnetic Resonance Centre, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, 2Nottingham University Hospitals NHS Trust, United Kingdom, 3School of Psychology, University of Nottingham, United Kingdom, 4Medical Schools and Nursing Centres, University of Nottingham, United Kingdom, 5School of Clinical Sciences, University of Nottingham, United Kingdom, 6School of Biomedical Sciences, University of Nottingham, United Kingdom

 
Pregnancy complicated by diabetes often results in macrosomic infants (birth weight > 4000g). They are at increased risk of shoulder dystocia, brachial plexus injury, prolonged labor and caesarean section. The fetuses are at higher risk of becoming obese and developing Type 2 diabetes. We show significant increase in fetal fat volume, percentage fetal fat and fetal length but not total fetal volume at 33–37 weeks in diabetics compared to controls. In utero assessment of fetal size and fat distribution would allow clinicians to identify fetuses at risk of complicated delivery and study the metabolic changes in the infant.

 
4140.   88 Antenatal liver and spleen iron quantification in a sheep model
Jin Yamamura1, Björn Schoennagel2, Chressen Much3, Roland Fischer4,5, Gerhard Adam2, and Ulrike Wedegaertner2
1Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Hamburg, Hamburg, Germany, 2Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Germany, 3Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, 4Pediatric Haematooncology, University Medical Center Hamburg-Eppendorf, Germany, 5Children's Hospital and Research Center Oakland, Oakland, California, United States

 
Antenatal liver and spleen iron quantification in a sheep model

 
4141.   89 Using Dynamic Contrast Enhanced MRI to Quantitatively Characterize Maternal Vascular Organization in the Primate Placenta
Christopher D. Kroenke1, Antonio E. Frias1, Matthias C. Schabel1, Peta L. Grigsby1, Victoria H.J. Roberts1, Kevin L. Grove1, Karen Y. Oh1, and Alina Tudorica1
1Oregon Health & Science University, Portland, United States, United States

 
A method is described for quantifying maternal perfusion in the primate placenta using dynamic contrast enhanced MRI. In contrast to rodents, the primate placenta is organized into several 2-5 mL vascular structures termed cotyledons. We have characterized perfusion within the placental intervillous spaces of the macaque placenta at several stages of pregnancy by analyzing contrast reagent arrival time as a function of distance from spiral artery inputs. As a result, intervillous blood flow is quantified for each cotyledon. Substantial heterogeneity in blood flow is observed between cotyledons and between individual subjects, indicating the potential of this analysis for assessing placental function.

 
4142.   90 Estimation of placenta function using T2* measurements during hyper- and normoxia
David Alberg Peters1, Anne Sørensen2, Ernst-Torben Wilhelm Fründ3, Ole Bjarne Christiansen2, and Niels Uldbjerg4
1Department of Clinical Engineering, Central Denmark Region, Aarhus N, Denmark, 2Department of Gynecology and Obstetrics, Aarhus University, Aalborg Hospital, Aalborg, Denmark, 3Department of Radiology, Aarhus University, Aalborg Hospital, Aalborg, Denmark, 4Department of Gynecology and Obstetrics, Aarhus University Hospital, Skejby, Aarhus N, Denmark

 
MR is becoming more widely used for prenatal diagnosis, with the main focus being to detect structural changes in the fetus. Recently some groups have explored the use of functional MR in fetuses. These studies have mainly studied the effects in fetal organs in sheep. In this study we present a method for detecting the effects of oxygen breathing in placenta and the initial results from six healthy pregnant women. With further development this method could be used to evaluate placental function and determine the optimum time to deliver growth restricted fetuses.

 
4143.   91 IVIM Assessment of the Placenta, Basal Plate and Chorionic Plate in Diabetic Pregnancies
Devasuda Anblagan1, Ruta Deshpande2, Nia W Jones2, Carolyn Costigan1, Caroline Wright3, David M Morris4,5, Nick Raine Fenning6, Lopa Leach7, George Bugg2, Peter Mansell2, and Penny Gowland1
1Sir Peter Mansfield Magnetic Resonance Centre, University of Nottingham, Nottingham, Nottinghamshire, United Kingdom, 2Nottingham University Hospitals NHS Trust, United Kingdom, 3Maternal and Fetal Health Research Group, University of Manchester, Manchester, United Kingdom, 4Imaging Sciences, University of Manchester, Manchester, United Kingdom, 5Biomedical Imaging Institute, University of Manchester, Manchester, United Kingdom,6School of Clinical Sciences, University of Nottingham, United Kingdom, 7School of Biomedical Sciences, University of Nottingham, United Kingdom

 
High volume, low resistance placental blood flow (f) is essential for optimal nutrient exchange. Aberrant placental blood flow is associated with conditions such as maternal diabetes, often resulting in areas with abnormal vascular development. This study is the first report of measurements of IVIM in the chorionic plate. The results show no change in f with gestational age, (consistent with previous results in basal plate and placenta). No significant changes were found in diabetes.

 
4144.   92 Placental infarction in fetal MRI: value of flow voids between the uterus and the placenta
Yoshimitsu Ohgiya1, Hiroshi Nobusawa2, Jumpei Suyama1, Syouei Sai1, Makoto Saiki1, Takashi Hashizume1, Noritaka Seino1, Masanori Hirose1, and Takehiko Gokan1
1Showa University School of Medicine, Tokyo, Japan, 2Kawasakisaiwai hospital, Kawasaki, Japan

 
The purpose of this study was to evaluate diminished flow voids on T2-weight RARE MR imaging of the placenta in fetuses with and fetuses without IUGR who were suspected of having placental infarction. The use of diminished flow voids in addition to morphologic signs increased sensitivity for the detection of placental infarction from 66.7% to 83.3%, increased accuracy from 81.5% to 86.8%, and preserved specificity at 90.0%. Evaluating flow voids on T2-weighted RARE images can be useful for detecting placental infarctions, particularly in placentas without morphologic signs on MR imaging.

 
4145.   93 In amnio MRI imaging for the identification of abdominal pathologies
Tom Roberts*1,2, Francesca Norris*1,2, Helen Carnaghan3, Jack Wells1, Bernard Siow1,4, Peter J Scambler1, Agostino Pierro3, Simon Eaton3, and Mark Lythgoe1
1UCL Centre for Advanced Biomedical Imaging, Division of Medicine and Institute of Child Health, University College London, London, United Kingdom,2Centre for Mathematics and Physics in Life Sciences & Experimental Biology (*Joint First Authors), University College London, London, United Kingdom,3Paediatric Surgery Unit, UCL Institute of Child Health, University College London, London, United Kingdom, 4Centre for Medical Image Computing, University College London, London, United Kingdom

 
Ex vivo MRI is a successful, non-invasive technique for studying disease development and gene function in mutant mouse models. However, there is currently no established method for assessing ex vivo embryos retained in the amniotic sac using MRI. Such a method would be valuable for determining the phenotypes of mutant embryos with abdominal wall defects such as gastroschisis and omphalocele, which are difficult to distinguish between using light microscopy. In this study, we developed a novel methodology to visualise "in amnio" embryos and successfully applied the technique to image a fetus with an omphalocoele defect.

 
4146.   94 MR Compatible Fetal Electrocardiogram Gating
Martyn NJ Paley1, Michael Reeves1, and Paul D Griffiths1
1Academic Radiology, University of Sheffield, Sheffield, Yorkshire, United Kingdom

 
An MR compatible fetal electrocardiogram gating (fECG) system has been tested on pregnant female volunteers. Single shot Fast spin Echo images have been acquired gated to the fetal ECG although gradient pickup was detected during imaging sequences.

 
4147.   95 Whole body fetal MRI at 3D-true-FISP imaging
Tetsu Niwa1, Koki Kusagiri1, Yasuhiko Tachibana1, Hiroshi Ishikawa2, Tomoaki Nagaoka3, Kumiko Nozawa1, and Noriko Aida1
1Radiology, Kanagawa Childnren's Medical Center, Yokohama, Kanagawa, Japan, 2Obstetrics and Gynecology, Kanagawa Children's Medical Center, Yokohama, Kanagawa, Japan, 3National Institute of Information and Communications Technology, Koganei, Japan

 
Whole body fetal MRI at 3D-true-FISP

 
4148.   96 Lung-to-liver signal intensity ratio of fetal magnetic resonance imaging: Comparison between HASTE and true-FISP imaging.
Tetsu Niwa1, Noriko Aida1, Yasuhiko Tachibana1, Kumiko Nozawa1, Tomoaki Nagaoka2, and Hiroshi Ishikawa3
1Radiology, Kanagawa Children's Medical Center, Yokohama, Kanagawa, Japan, 2EMC Group, National Institute of Information and Communications Technology, Koganei, Tokyo, Japan, 3Obstetrics and Gynecology, Kanagawa Children's Medical Center, Yokohama, Kanagawa, Japan

 
fetal lung to liver signal at true-FISP