MRA & Flow of Neurovascular Diseases

Hall D                                   Tuesday 13:30-15:30                                                                                                                                             

13:30         3416.     A Novel Technique of Cranial MR Angiography: Hybrid MRA

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Takao Kodama1, Takanori Yano1, Shozo Tamura1, Yoshio Machida2, Tokunori Kimura2

1Faculty of Medicine, University of Miyazaki, Miyazaki, Japan; 2Toshiba Medical Systems, Otawara, Japan

We developed a new MRA sequence, hybrid MRA (HMRA), combining the contrast of time-of-flight (TOF) and flow-sensitive black blood (FSBB) by using the dual-echo data acquisition. The gradient moment nulling (GMN) and dephasing gradient was applied to obtain the first echo and the second echo, respectively. Original images of the HMRA were made by subtracting the second-echo images from the first-echo images. This sequence was more sensitive to slow flow than 3D TOF MRA and seemed to be a feasible technique or evaluating steno-occlusive vascular disease.

 

14:00         3417.     GRAPPA with a TWIST: Dynamic 4D CE MRA of the Cerebral Vasculature at Near Isotropic Resolution

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Jens Olaf Heidenreich1, Martin Blaimer1, Randall Kroeker, Gerhard Laub, Jeffrey L. Duerk1, Jeffrey Sunshine1, Mark Griswold1

1Case Western Reserve University, Cleveland, USA

GRAPPA and TWIST were combined to a novel 4D dynamic high resolution contrast enhanced magnetic resonance angiography allowing for the first time to image the entire cerebral vasculature during a contrast bolus passage at near isotropic resolution. In 25 neurological patients this technique showed improved small vessel depiction over the current clinical standard TOF-MRA. It also delivered superior results in patients prone to motion and those with metal artifacts. The simplicity of data acquisition makes bolus timing unnecessary, readily shows all phases of anatomy from arteries through veins, and can strongly impact imaging of patient cerebral vasculature in daily practice.

 

14:30         3418.     Phase Contrast Flow Quantification of Carotico-Vertebral Blood Flow at 3.0T in Patients with Angiographically Normal Vessels

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Fatemeh Barkhordarian1, Derek G. Lohan1, Aparna Singhal1, reza habibi1, Abbas Nasiraei-Moghaddam1, Roya Saleh1, Pablo Villablanca1, Paul J. Finn1

1UCLA, Los Angeles, USA

Precise quantification of cerebral blood volume flow with combined morphological and hemodynamic data has many potential applications in neurovascular imaging.We sought to evaluate the normal ranges of caroticovertebral blood flow in a large number of patients with normal MR Angiography using a high temporal resolution protocol at 3.0 Tesla,thus providing reference values for future access and suggest that there is considerable variability in ‘normal’ cerebral blood flow in the absence of strong relationship with patient age or gender.   

 

15:00         3419.     Using Vessel Encoded Arterial Spin Labeling Technique to Evaluate Cerebral Blood Flow Territories in Volunteers and Carotid Occlusion Patients

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WU Bing1,2, GUO Jia3, Wong Eric C.4, WANG Xiaoying1,3, ZHANG Jue3, JIANG Xue-xiang1, FANG Jing3

1Peking University 1st Hospital, Beijing, People's Republic of China; 2Peking University , Beijing, People's Republic of China; 3Peking University, Beijing, People's Republic of China; 4University of California,

We present a new method, vessel encoded imaging(VEI), for evaluating the individual brain-feeding arteries of healthy volunteers and carotid occlusion patients quantitatively and qualitatively. VEI can measure elective cerebral blood flow (sCBF) mapping of the flow territories of the left and right internal carotid arteries and vertebrobasilar arteries, which could aid in the planning and staging of interventions such as carotid endarterectomy, stenting, or bypass.

 

13:30         3420.     Non-Contrast MR Angiography with Multiple Inversion Pulses: Separation of Arteries from Veins with Flexible Inversion Time

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Naoyuki Takei1, Mitsuharu Miyoshi1, Tetsuji Tsukamoto1

1GE Yokogawa Medical Systems.Ltd, Hino, Japan

Selective inversion recovery pulse (SIR) has been used for non-contrast agent MR angiography. However in-flow time is restricted to the inversion time (TI). Aim of our study is to enhance depiction of arteries with longer in-flow time over TI for background suppression. At first SlR is applied. After a waiting time, non-selective inversion pulse follows. The multiple inversion pulses offer a longer in-flow time. Separation of arteries from veins was successfully performed with TI=1300 to 2000 ms in volunteer scans. This method provides a longer in-flow time of arteries than the T1 value of vein and improved depiction of arteries.

 

14:00         3421.     Carotid Plaque Imaging with BLADE

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Masahiro Ida1, Kennichi Motoyoshi1, Hiroyuki Fukuyama1, Hisashi Yoshizawa1, Naoya Yorozu1, Keiko Hino1

1Tokyo Metroplolitan Ebara Hospital, Oota-ku, Japan

BLADE-T2WI and T1WI are feasible for detecting not only atherosclerotic carotid plaque but also the neighboring

turbulent flow, which is a risk factor of the intimal injury. Multi-slice BLADE sequences are useful methods and the initial sequences of choice for screening of carotid plaque and its risk factor.BLADE dark blood (DB) sequences with cardiac gating are the best-preferred methods for precise evaluation of anatomical details and plaque contents. When multi-slice BLADE T2WI and T1WI show positive findings, single-slice BLADE-DB sequences with cardiac gating should be added to access carotid plaque precisely.

 

14:30         3422.     Assessment of Intracranial Aneurysm Thrombosis with Patient-Specific Computational Models Based on MRI Data

Vitaliy L. Rayz1, Loic Boussel1,2, Joseph R. Leach1, Gabriel Acevedo-Bolton1, Randall T. Higashida3, Michael T. Lawton3, Alastair J. Martin3, William L. Young3, David Saloner,13

1VA Medical Center, San Francisco, USA; 2Créatis-LRMN (LB, PCD),  UMR CNRS 5515, INSERM U630, Lyon, France; 3University of California San Francisco, USA

MR imaging and velocimetry were used to predict the flow in patients who had thrombus-free vessels, and then proceeded to develop intra-aneurysmal thrombus. High resolution, contrast-enhanced MRA images were used to obtain patient-specific lumenal geometries. Images obtained at baseline and at follow up studies were co-registered to determine regions of thrombus formation. Computational Fluid Dynamics (CFD) models were constructed using the baseline geometries and inlet conditions. Results indicate a strong similarity between the slow flow regions predicted in CFD simulations and the regions filled with thrombus in vivo. This study indicates computational models may offer guidance for cerebral aneurysms treatment.

 

15:00         3423.     Evaluation of Unruptured Intracranial Aneurysms with 3 Tesla 3D Time-Of-Flight MR Angiography : Comparison of 64-Channel Multidetector Row CT Angiography

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Yoshiyasu Hiratsuka1, Hitoshi Miki1, Keiichi Kikuchi1, Ikuko Kiriyama1, Teruhito Mochizuki1, Shizue Takahashi2, Ichiro Matsubara3, Kazuhiko Sadamoto3

1Ehime University School of Medicine, Toon, Japan; 2Ehime National Hospital, Toon, Japan; 3Washo-kai Sadamoto Hospital, Matsuyama, Japan

The purpose of this study was to compare 3D time-of-flight magnetic resonance angiography (3D TOF MRA) at 3 tesla (T) and 64-channnel multidetector row computed tomographic angiography (64-MDCTA) in the detection of angiographically proved unruptured intracranial aneurysms with a blind reader study.3 T 3D TOF MRA and 64-MDCTA are excellent examinations with high diagnostic accuracy for detection of unruptured intracranial aneurysms. These two modalities have the almost same ability for evaluation of intracranial aneurysms, and there is no significant difference. 3D TOF MRA is free from the risks concerning the use of contrast media or the exposure of x-ray, and widely applied for the screening examination of evaluation of intracranial aneurysms. From this results, with regard to the evaluation of intracranial aneurysms, improvement of diagnosis on 3 T TOF MRA will reduce the necessity for the additional CTA examination after MRA.

 

13:30         3424.     Can the Hemodynamic Geographical Factors Be the Cause of Concurrent Cavernous Malformation in the Cerebral Developmental Venous Anomaly? [Not Available]

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Yoo Jin Hong1, Tae-Sub Chung2, Kwon Duk Seo1, Sang Hyun Suh2, Kyung Yul Lee2

1Yongdong Severance Hospital,Yonsei University College of Medicine, Seoul, Republic of Korea; 2Yongdong Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea

Hemodynamic disturbance within the territory DVA by geographical factors may be a key factor in leading to cascade of events and subsequent development of a CM and 3.0 T high resolution MR units would be helpful to depict the find morphological detail of small vascular structures of DVA and CM and find such hemodynamic geographical factors.

 

14:00         3425.     Flow-Sensitive Black Blood Imaging for Evaluating Vascular Malformations

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Takao Kodama1, Takanori Yano2, Shozo Tamura1, Yoshio Machida3, Tokunori Kimura3

1Faculty of Medicine, University of Miyazaki, Miyazaki, Japan; 2Faculty of Medicine, University of Miyazaki,, Miyazaki, Japan; 3Toshiba Medical Systems, Otawara, Japan

The Purpose of this study was to estimate the utility of the newly developed flow-sensitive black blood (FS-BB) sequence in the evaluation of the vascular malformations. On the FS-BB imaging, the vascular structures can be enhanced by applying the dephaging gradient to susceptibility-weighted imaging. All venous malformations were more clearly visualized on FS-BB than flow-insensitive black blood (FI-BB) images. On FS-BB images, all of arteries, niduses, veins, and hemorrhagic lesions appeared as gblackh structures in patients with arteriovenous malformation or dural arteriovenous fistula. FS-BB can be a feasible tool for evaluating vascular malformations.

 

14:30         3426.     Imaging the Cerebral Venous Sinuses’ Puls Curve by Ultrafast Dynamic BOLD MRI

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Jan-Hendrik Buhk1,2, Gunther Schütze1, Kai Kallenberg1, Gunther Helms1, Jürgen Baudewig1, Andreas Wellmer1, Michael Knauth1, Peter Dechent1

1University Göttingen, Göttingen, Germany

Fast and dynamic imaging of the cerebral venous sinuses’ puls curve could be a useful additional tool in clinical diagnostic imaging of diseases like cerebral sinus thrombosis. We present a pilot study to evaluate the possibilities of fast dynamic single-slice blood oxygen level dependent (BOLD) imaging in displaying rhythmic signal changes in the cerebral venous sinuses. These findings highly correlate with reference techniques like phase contrast angiography (PCA) and duplex sonography, therefore the demonstration of an intracranial venous pulse curve is feasible.

 

15:00         3427.     Quantification of Cerebrovascular Reactivity by BOLD MRI and Correlation with Conventional Angiography in Patients with Moyamoya Disease

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Chris Heyn1, Julien Poublanc1, Jay S. Han2, Danny M. Mandell1, Jeff A. Stainsby3, Adrian P. Crawley1, Karel G. terBrugge1, Joseph A. Fisher2, David J. Mikulis1

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

Moyamoya disease (MMD) is a vasculopathy characterized by progressive narrowing of proximal circle of Willis vessels and the formation of secondary collaterals.  As the disease advances, adequate perfusion distal to vessel stenoses is lost when compensatory vasodilatation reaches a maximum.  Further increases in vascular resistance ultimately leads to tissue oligemia and possible ischemia.  Recently, we have developed a methodology for rapidly and accurately controlling end tidal PCO2 utilizing a CO2 rebreathing device.  Using this technique with blood oxygen level dependent (BOLD) MRI, a quantitative map of cerebrovascular reactivity (CVR), defined as the change in MR signal per mmHg change in end tidal PCO2, can be generated for patients with MMD.  In the present work, we apply BOLD CVR to patients with MMD and correlate the quantitative high resolution maps with angiographic features found on conventional vessel angiography.  Reduction in mean CVR correlates well with the degree of MMD disease measured by modified Suzuki score or the presence of moya vessels and pial collaterals as visualized by conventional angiography.

 

Multiple Sclerosis: Disease Severity, Progression

Hall D                                   Tuesday 13:30-15:30                                                                                                                                             

13:30         3428.     The Relationship Between Brain NAWM and GM Damage is Localised to Specific Clinically Relevant Regions in Early PPMS

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Benedetta Bodini1,2, Zhaleh Khaleeli1, Mara Cercignani1,3, David H. Miller1, Alan J. Thompson1, Olga Ciccarelli1

1University College of London, London, UK; 2Sapienza, Università di Roma, Roma, Italy; 3Fondazione Santa Lucia, Roma, Italy

We used tract based spatial statistics and voxel based morphometry to assess separately white and grey matter abnormalities in patients with early primary progressive MS to clarify in vivo the relationship between the pathological processes occurring in the two compartments. We found 11 areas of anatomical correspondence between white and grey matter damage; however, when investigating the presence of a quantitative correlation, this was only found in 4 clinically eloquent regions. In such regions, we found that grey and white matter damage contribute to disability independently from each other.

 

14:00         3429.     MRI Correlates of Hippocampal Demyelination in Multiple Sclerosis Brains

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Elizabeth Fisher1, Ansi Chang1, Kunio Nakamura1, Richard A. Rudick1, Bruce D. Trapp1

1Cleveland Clinic, Cleveland, Ohio, USA

Histopathologic studies have demonstrated extensive demyelination in hippocampus in MS brains, but MRI correlates have not been defined. To investigate whether hippocampal pathology can be detected using common MRI sequences, we compared imaging characteristics in normally myelinated (n=4) and severely demyelinated (n=5) hippocampi obtained from MS patients post-mortem. MRIs were acquired in situ, prior to tissue fixation. Mean T2, T1, and MTR contrast ratios were not different, but MTR histograms from demyelinated hippocampi were shifted downward. These data suggest that MTR histogram peak position may a marker of hippocampal pathology in MS patients.

 

14:30         3430.     Cognitive Dysfunction in Benign MS is Associated with Increased Severity of Corpus Callosum Damage

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Elisabetta Pagani1, Sarlota Mesaros1, Marco Rovaris1, Domenico Caputo2, Angelo Ghezzi3, Ruggero Capra4, Antonio Bertolotto5, Gianna Riccitelli1, Vittorio Martinelli1, Giancarlo Comi1, Massimo Filippi1

1Scientific Institute and University Ospedale San Raffaele, Milan, Italy; 2Scientific Institute Don Gnocchi, Milan, Italy; 3Ospedale di Gallarate, Gallarate, Italy; 4Spedali Civili, Brescia, Italy; 5O

In this study we wished to investigate the relationship between the cognitive profile of benign multiple sclerosis (BMS) patients and the extent of tissue damage in the corpus callosum (CC). A method, which enables us to track and investigate atrophy and tissue damage of the CC was used in 54 BMS patients and correlations with neuropsychological tests (NPT) exploring memory, attention and frontal lobe cognitive domains were investigated. We found that cognitive dysfunction is associated with an increased severity of CC damage, in terms of both discrete lesions and fiber bundle disruption.

 

15:00         3431.     Changes in Blood-Brain Barrier Permeability and Blood Volume During MS Lesion Development and Evolution

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Jeffrey Moses Njus1, Xin Li1,2, Charles S. Springer1,2, Maria Taylor3, Tiana Greisel1, Frank W. Telang2, Patricia K. Coyle3, William D. Rooney1,2

1Oregon Health and Science University, Portland, Oregon, USA; 2Brookhaven National Laboratory, Upton, USA; 3Stony Brook University, Stony Brook, USA

Brain 1H8O R1 [&[ident] T1-1] data were collected from 12 healthy controls and 16 MS subjects at 4 T before and after gadolinium contrast reagent administration.  Normal appearing white and gray matter ROIs were selected and Ktrans and mole fraction blood water (pb) values were compared between control and MS groups.  These were monitored during the development and evolution of MS lesions.

 

13:30         3432.     Correlation of Regional Brain Tissue Loss and Disease Severity in Relapsing-Remitting Multiple Sclerosis: A VBM Study in a Large Patient Population

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Anna Prinster1, Mario Quarantelli1,2, Roberta Lanzillo3, Carmine Mollica2, Petronilla Salvatore2, Giuseppe Orefice2, Bruno Alfano1, Vincenzo Brescia Morra2, Arturo Brunetti,12, Marco Salvatore2

1National Research Council, Naples, Italy; 2University "Federico II", Naples, Italy; 3Hermitage Hospital IDC, Naples, Italy

Possible correlations between brain tissue loss and clinical severity were investigated using optimized VBM in 128 RR MS patients, showing a preferential correlation with EDSS of GM volume reduction in the primary motor cortex bilaterally, with an associated preferential right-sided tWM loss in subcortical regions stemming from the rolandic areas and following the pyramidal tract down to the brainsteam.

 

14:00         3433.     Susceptibility-Weighted MR Imaging of Vascular Distribution in White-Matter MS Lesions

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Jennifer Elizabeth Dixon1, Emma C. Tallantyre1, Paul S. Morgan1, Matthew J. Brookes1, Nikos Evangelou1, Peter G. Morris1

1The University of Nottingham, Nottingham, UK

The relationship between white-matter MS lesions and parenchymal blood vessels has been found to be predictive of treatment response, and is therefore of considerable clinical interest. Previous in vivo studies have been limited by the inability to view both the lesion and blood vessel on one MR image, resulting in the failure to determine their exact spatial relationship. In this study, we present susceptibility-weighted MR imaging at 7 Tesla as a technique for the identification of both lesions and blood vessels, aiding the study of the perivascular distribution of MS lesions.

 

14:30         3434.     DCE-MRI Ktrans Mapping of MS Lesion Evolution in Individuals

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Jeffrey Moses Njus1, Xin Li1,2, Charles S. Springer, Jr.1,2, Maria Taylor3, Frank W. Telang2, Patricia K. Coyle3, William D. Rooney1,2

1Oregon Health and Science University, Portland, Oregon, USA; 2Brookhaven National Laboratory, Upton, USA; 3Stony Brook University, Stony Brook, USA

Transient focal disruption of the blood-brain barrier (BBB) is the most pronounced cerebrovascular abnormality in multiple sclerosis (MS) brain tissue.  Though serial MRI studies involving gadolinium (Gd) contrast reagents have provided evidence that BBB permeability compromise is among the earliest expressions of MS pathology detectable by imaging techniques, quantitative BBB permeability changes throughout the course of lesion evolution have not be examined. In this study, we apply pharmacokinetic mapping techniques via dynamic-contrast-enhanced (DCE) MRI as means of investigating quantitative BBB permeability heterogeneity changes in relapsing-remitting MS (RRMS) brain tissue throughout the different phases of lesion development.

 

15:00         3435.     Deep Gray Matter Atrophy as an MRI Metric of Physical and Cognitive Impairment in Patients with Multiple Sclerosis

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Antonio Gallo1, Iordanis E. Evangelou1, Vasiliki N. Ikonomidou1, Robert L. Kane, Susan K. Stern1, Joan M. Ohayon1, Fredric Cantor1, Henry McFarland1, Francesca Bagnato1

1National Institutes of Health, Bethesda, Maryland, USA

We investigated the role of deep gray matter (dGM) atrophy in determining physical and cognitive impairment in patients with Multiple Sclerosis (MS). Twenty-four MS patients and 24 age-, gender- and education-matched healthy volunteers (HVs) underwent 3T MPRAGE, clinical and an extensive neuropsychological evaluation. dGM structures were segmented using the FreeSurfer software and volumes of both the thalamus (Th-vol) and basal ganglia (BG-vol) were obtained. Th-vol was significantly reduced in MS patients with respect to HVs, whereas differences in BG-vol did not reach statistical significance. Further analysis showed that atrophy of dGM structures correlated well with physical and several cognitive scores.

 

13:30         3436.     Correlating Iron with T2 Signal Intensity in Multiple Sclerosis Lesions Using Susceptibility Weighted Imaging

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E. Mark Haacke1, Malek Makki1, Yulin Ge2, Megha Maheshwari1, James Garbern1, Omar Khan1, Jiani Hu1, Madesh Selvan1, Latif Zahid1

1Wayne State University, Detroit, Michigan, USA; 2New York University, New York, New York, USA

Susceptibility weighted imaging (SWI) filtered phase data provides a means to monitor changes in iron content from hemosiderin. We used SWI to image multiple sclerosis lesions and compare them to those seen in T2 imaging. We find that the putative iron content associated with SWI phase images correlates negatively with T2 hyperintensities in multiple sclerosis lesions.

 

14:00         3437.     Automated System for Temporal Tracking of Multiple Sclerosis Lesions

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Michel Bilello1, Chamith S. Rajapakse1, Neerav Mehta1, Ragini Verma1, Elias R. Melhem1

1University of Pennsylvania, Philadelphia, USA

Interpretation of MRI scans of multiple sclerosis patients can be a very challenging task for the neuroradiologist due to changes in size, shape and position of the lesions. Manual tracking of temporal evolution of lesions is time and labor intensive and prone to inter-rater variability. Some of these limitations and challenges can be overcome by using a standardized automated system presented here. The accuracy and robustness of the predictions given by the automated system was validated with data made available by collaborative MS studies and those generated by a modified protocol.

 

14:30         3438.     Multiparametric MR Analysis of Temporal Evolution of Abnormality in MS

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Nematollah Batmanghelich1, Xiaoying Wu1, Christos Davatzikos1, Clyde E. Markowitz1, Ragini Verma1

1University of Pennsylvania, Philadelphia, USA

Various modalities, have been used individually to quantify damage in the normal appearing brain tissue(NABT); however, few studies combine these modalities to derive better information about tissue abnormality, with most methods concentrating on lesion segmentation rather than tissue abnormality characterization. We combine several MR modalities into a probabilistic pattern classification method to determine a voxel-wise probabilistic tissue abnormality score. This score can then been correlated with clinical and cognitive scores to study temporal WM changes. This method is applicable to studying treatment effects and can help physicians determine the extent of abnormality beyond the conventional visual symptoms like lesions.

 

15:00         3439.     A Voxel-Wise Random Field Theory-Based Magnetization Transfer Approach for Detecting Focal Demyelination and Remyelination in Multiple Sclerosis

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Michael G. Dwyer1, Milena Stosic1, Sara Hussein1, Arpad Kelemen1, David Wack1, Robert Zivadinov1

1State University of New York at Buffalo, Buffalo, New York, USA

Magentization transfer imaging (MTI) may provide a means for detecting demyelination and remyelination in-vivo in patients with multiple scelrosis.  We demonstrate a sensitive and statistically sound technique for identifying and quantifying areas of focal magentization transfer ratio (MTR) via longitudinal MTI.  This method is based on random field theory (RFT), and may have significant sensitivity and specificity advantages over whole-brain, region-of-interest, or purely voxel-wise approaches.

 

13:30         3440.     Voxel Based DTI Analysis Predicts Suggestive of MS Track in Clinically Isolated Syndrome Patients

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Yasheng Chen1, Valerie Jewells1, Silva Markovic-Plese1, Hongtu Zhu1, Diane Armao1, Hongyu An1, Elizabeth Bullitt1, Weili Lin1

1The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA

Patients presenting as clinically isolated syndrome (CIS) were imaged using DTI and were clinically evaluated ~2yrs after the initial DTI scans.  Based on the clinical status, patients were divided into two groups: suggestive of multiple sclerosis (CIS-MS) and not suggestive of MS (CIS-NMS).  Voxel-based analysis of the baseline DTI revealed that CIS-MS patients demonstrated significantly more severe sub-cortical abnormalities when compared with CIS-NMS patients.  Thus, our findings strongly supported that DTI may be a powerful imaging marker to predict CIS patients who may evolve into MS in future, allowing potentially early therapeutic intervention to reverse/retard the disease processes.

 

14:00         3441.     Structural MRI Correlates of Benign Multiple Sclerosis. A Voxel-Based Morphometry Study of Regional Grey Matter Atrophy

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Elisabetta Pagani1, Sarlota Mesaros1, Marco Rovaris1, Domenico Caputo2, Mauro Zaffaroni3, Ruggero Capra4, Antonio Bertolotto5, Vittorio Martinelli1, Giancarlo Comi1, Massimo Filippi1

1Scientific Institute and University Ospedale San Raffaele, Milan, Italy; 2Scientific Institute Don Gnocchi, Milan, Italy; 3Ospedale di Gallarate, Gallarate, Italy; 4Spedali Civili, Brescia, Italy; 5O

We used voxel-based morphometry to assess regional grey matter (GM) atrophy changes in 60 patients with benign mulitple sclerosis (BMS), 35 with secondary progressive (SP) MS and 21 controls. Compared to controls, SPMS patients showed a pattern of widespread GM atrophy, while BMS had reduced GM volume in the subcortical and frontoparietal regions. In comparison with BMS patients, those with SPMS had significant GM loss in the both cerebellar hemispheres, as well as in the right nucleus dentatus. Cerebellar atrophy seems to be a major determinant of irreversible locomotor disability in MS.

 

14:30         3442.     Segmentation of 3T Diffusion Tensor Images with Multiple Sclerosis Lesions

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Mustafa Okan Irfanoglu1, Steffen Sammet1, Regina Maria Koch1, Raghu Machiraju1, Michael V. Knopp1

1The Ohio State University, Columbus, Ohio, USA

Diffusion Tensor Imaging has a significant use in early diagnosis of Multiple Sclerosis (MS). The traditional methods of MS lesion detection are based on building statistical distributions of white matter fractional anisotropy (FA) and diffusivity (ADC) of healthy regions and trying to detect deviations from these distributions. In this study, we propose a novel method for segmenting diffusion tensors, which makes use of the entire tensor information instead of derived scalar fields and use this segmentation approach to detect candidate MS lesions.

 

15:00         3443.     High-Resolution in Vivo Imaging of Cortical Lesions in Multiple Sclerosis: A Comparison of 3T and 7T

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Jennifer Elizabeth Dixon1, Paul S. Morgan1, Emma C. Tallantyre1, Matthew J. Brookes1, Nikos Evangelou1, Peter G. Morris1

1The University of Nottingham, Nottingham, UK

Post-mortem MS studies have shown significant demyelination of the deep and cortical grey matter (GM), but in vivo study is made difficult due to the insensitivity of MRI to this type of lesion. The spatial resolution and contrast mechanisms available at 7T appears to be advantageous in the detection and delineation of these lesions, suggesting that it will be a useful tool in the study of cortical pathology.

 

13:30         3444.     3T Sodium MRI of Patients with Multiple Sclerosis

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Guillaume Madelin1, Niels Oesingmann2, Sonia Nielles-Vallespin3, Joseph Herbert1, Glyn Johnson1, Matilde Inglese1

1New York University, New York, New York, USA; 2Siemens Medical Solutions, New York, New York, USA; 3AG Siemens Medical Solutions, Erlangen, Germany

Axonal degeneration occurs from the onset of multiple sclerosis (MS) and it is thought to be a significant cause of disability. Several studies have shown that the accumulation of sodium in the axons can promote degeneration. Sodium MRI provides an indicator of cellular and metabolic integrity and has been applied to the study of patients with brain tumors and stroke. The aim of this study was to demonstrate the feasibility of performing sodium MRI of the brain in patients with MS and to report preliminary results of the changes of tissue sodium concentration in MRI-visible lesions and normal-appearing white matter.

 

14:00         3445.     Definition and Classification of Registration Artifact (“Yin Yang” Artifact) on MR Subtraction Imaging in Multiple Sclerosis (MS): A Pilot Study

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Yang Duan1,2, Mehu P. Sampat1, Peter G. Hildenbrand1, David F. Tate1, Yi Tang1, Annika M. Berger1, Dominik S. Meier1, Charles R.G. Guttmann R.G Guttmann1

1Brigham and Women’s Hospital Harvard Medical School, Boston, Massachusetts, USA; 2The First Hospital, China Medical School, Shenyang, People's Republic of China

We analyzed YYA based on the underlying registration mechanism, to facilitate in understanding of the their causes and accuracy in interpreting lesion progressions on subtraction images. Dual echo PD/T2 weighted MR images were acquired, co-registered, intensity normalized and subtracted. YYA is a counterpoised increase and decrease of signal changes around lesions on subtraction images. YYA was identified and classified into four subtypes by radiologists according to mis-registration orientation, corresponding to patients’ movement on right-left (I), anterior-posterior (II), cranial-caudal (III) and combined shifting dimension (IV) respectively. Type III and IV occurred more frequent than type II and I. 

  

14:30         3446.     Coarseness of MRI Texture in Acute Lesions Relates to Subsequent Recovery Activity in Multiple Sclerosis

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Yunyan Zhang1, Hongmei Zhu2, Joseph Ross Mitchell1, Luanne M. Metz1

1University of Calgary, Calgary, Canada; 2York University, Toronto, Canada

Texture property in new multiple sclerosis (MS) lesions were quantified on 1.5T T2-weighted MRI 2 months before and 8 months after the appearance of gadolinium-enhancement using the multiscale polar Stockwell transform (PST). Seven/12 lesions were persisting (T2 hyperintensity) and 5/12 were invisible (no hyperintensity) 8 months post-enhancement. Significantly higher coarse texture (low frequency) was observed in the persisting lesions than that in the invisible lesions in the pre-lesional NAWM, during acute phase, and at chronic phase (P<0.05). This preliminary study indicates that the PST analysis may be useful in predicting lesion recovery on conventional T2-weighted MRI in MS.

 

15:00         3447.     Betainterferon Treatment: Absolute Quantification of White Matter Metabolites in Patients with Multiple Sclerosis

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Olof Dahlqvist Leinhard1,2, Jacek Jaworski1, Maria Gustavsson1, Anders Tisell1, Dominique Gladigau1, Anne-Marie Landtblom1, Peter Lundberg1

1University of Linkoping, Linkoping, Sweden

Multiple sclerosis can be treated with immunomodulatory drugs that can decrease the number and severity of bouts and also slower disability-progress. The mechanism, however is not fully understood. In order to improve the assessment of changes in the brain metabolome using MRS, a method was developed that allows for absolute quantification of metabolites as NAA, Cho, myo-Ins, Cr, Lac, Glc etc. Proton-MRS spectroscopy was performed before and after more than two years of betainterferon treatment. We report a decrease of NAA, as a marker of neuronal status and an increase of myo-Inositol due to degradation in these treated patients.

 

Prion Disease & Neurodegenerative Disorders

Hall D                                   Tuesday 13:30-15:30                                                                                                                                             

13:30         3448.     Cytoarchitecture of Frontal Cerebral Cortex in Variant Creutzfeldt-Jakob Disease: Post Mortem MR Microscopy at 9.4 Tesla

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Harpreet Hyare1,2, Po-Wah So2, John S. Thornton1, Caroline Powell1, Harry Parkes1, Durrenajaf Siddique1, Steve Wroe1, Sebastian Brandner1, Tarek Yousry1

1Institute of Neurology, London, UK; 2MRC Clinical Sciences Centre, Hammersmith Hospital, Imperial College London, London, UK

Ex vivo MRM at 9.4T can depict pathology characteristic of vCJD by demonstrating apparent loss of the normal intracortical laminations.  These observations will be increasingly relevant as high-field MRI systems with improved spatial resolution enter clinical practice, when in vivo assessment of the cerebral cortex may prove highly beneficial in the diagnosis and monitoring of vCJD

 

14:00         3449.     The Pulvinar Sign in Variant Creutzfeldt-Jakob Disease: Quantitative Diffusion-Weighted Imaging in Vivo at 1.5T and Ex Vivo at 9.4T with Histopathological Correlation

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Harpreet Hyare1,2, John S. Thornton1, Durrenajaf Siddique1, Laura Mancini1, Jager Rolf1, Steve Wroe1, Caroline Powell1, Sebastian Brandner1, Po-Wah So2, Tarek Yousry1

1Institute of Neurology, London, UK; 2MRC Clinical Sciences Centre, Hammersmith Hospital, Imperial College London, London, UK

Despite the hyperintensity seen on DWI, in vivo pulvinar ADCs were increased in vCJD compared with controls, suggesting that this pulvinar hyperintensity is a T2 effect, while histological analysis demonstrated that gliosis in the pulvinar is likely to be the pathological substrate.  Correlations between ex vivo FA and histopathological scores were negative for spongiosis and positive for gliosis, suggesting the latter may reinforce the directional organization of the neuropil. Future studies will determine the value of in vivo DTI metrics as pathologically specific indices of disease severity in vCJD.

 

14:30         3450.     Influence of B Factor on ADC Sensitivity in Creutzfeldt-Jakob Disease

Computer 47

Hedok Lee1, Andrew Degnan1, Chen Hoffmann2, Peter Barbara Kingsley3,4, Isak Prohovnik1

1Mount Sinai School of Medicine, New York, New York, USA; 2Chaim Sheba Medical Center, Israel; 3North Shore University Hospital, Manhasset, USA; 4New York University School of Medicine, New York, New York, USA

In this first rigorous test of the influence of b factor (1000 Vs 2000 s/mm^2) on the sensitivity of DWI to detect Creutzfeldt-Jakob disease, we scanned 13 CJD patients and 15 healthy relatives at both b levels, computed ADC, and quantitatively compared the results both in voxel-level (SPM5) and VOI (FSL) analyses.  The b=2000 data showed greater ADC reductions in patients compared to controls, and larger areas of statistically significant ADC reductions, especially in the thalamus and caudate nucleus.  The findings demonstrate that MRI can be more sensitive to reduced diffusivity in basal ganglia at b=2000 than at b=1000.

 

15:00         3451.     Global and Tissue-Specific Cerebral Magnetisation Transfer Ratios in Inherited Prion Disease: Correlation with Disease Severity

Computer 47

Durrenajaf Siddique1,2, S Wroe1,2, H Hyare2, T Webb1,2, R Macfarlane1,2, J Collinge1,2, S Walker3, T Yousry4, JS Thornton4

1National Prion Clinic, National Hospital for Neurology and Neurosurgery, London, UK; 2Institute of Neurology, Queen Square, London, UK; 3Medical Research Council Clinical Trials Unit, London, UK; 4Lysholm Depar

Inherited prion diseases (IPD) are progressive neurodegenerative disorders, conventional MR neuroimaging often being unremarkable. Global and tissue-specific cerebral magnetisation transfer ratios (MTRs) were investigated in twenty-three patients, using MTR and conventional imaging. Whole-brain, white and grey matter histogram mean, peak height, peak location, and MTR at the 25th, 50th and 75th percentile were calculated, and  patients evaluated using videoed and non-videoed neurological rating scales. Significant (p<0.01) bivariate Spearman rank correlations were found between multiple histogram parameters and clinical scores, with a single pathological conventional MR. MTR histogram measures may provide valuable indices of IPD disease severity for future therapeutic trials.

 

13:30         3452.     Postmortem Magnetisation Transfer Ratio in Human Prion Diseases at 1.5T and Histopathological Correlation at 9.4T

Computer 48

Durrenajaf Siddique1, Harpreet Hyare1, Steve Wroe1, John Collinge1, Caroline Powell1, Sebastian Brandner1, Po-Wah So2, Tarek Yousry1, John S. Thornton1

1Institute of Neurology, London, UK; 2MRC Clinical Sciences Centre, Hammersmith Hospital, Imperial College London, London, UK

We have shown for the first time that, ex vivo, MTR is lower in cortical and deep grey matter, but not white matter, in patients with prion disease compared to controls, presumably reflecting an increase in the fraction of free-to-bound water. In targeted high-resolution MTR measurements we have also shown that cortical MTR correlated negatively with increasing spongiosis, a histopathological feature unique to prion disease.  The major advantage of post mortem quantitative MRI is the possibility of direct comparison with histology; our results suggest that MTR may provide a useful in vivo surrogate marker for pathology in human prion disease.

 

14:00         3453.     Abnormal Connectivity Pattern of Fronto-Striatal-Thalamic Circuits of Patients with Tourette Syndrome Based on Probabilistic Tractography

Computer 48

Rajkumar Munian Govindan1, Malek Makki1, Michael Behen1, Harry T. Chugani1

1Wayne State University, Detroit, Michigan, USA

Volumetric and functional imaging studies of individuals with Tourette Syndrome (TS) have revealed regional abnormalities typically in structures comprising the fronto-striato-thalamic circuit.  However, few studies have evaluated connectivity between the components of this circuit.  With diffusion tensor imaging (DTI) and probabilisitic tractography, it is now possible to evaluate white matter integrity.  We used DTI tractography to evaluate fronto-striatal and fronto-thalamic connectivity in children with TS as compared to age and gender matched healthy controls.  Results showed decreased connectivity in fronto-striatal and fronto-thalamic pathways of TS group, which provides further support for the involvement of the fronto-striato-thalamic circuit in TS.

 

14:30         3454.     Combined 31P and 1H-MRS Study on Brain Energy Metabolism in Progressive Supranuclear Palsy (PSP)

Computer 48

Ulrich Pilatus1, Maria Stamelou, Jörg Magerkurth1, P Niklowitz, A Reuss, K M. Eggert, C Schade-Brittinger, W Oertel, Heiner Lanfermann1, G U. Höglinger

1Johann Wolfgang Goethe-Universität, Frankfurt, Germany

Progressive Supranuclear Palsy (PSP) is a sporadic neurodegenerative disorder. In vivo MRS using either 31P  or 1H  nuclei disclosed significant metabolic differences between patients and age-matched normal controls. This study was aimed at exploiting the full potential of combined 31P and 1H MRS to thoroughly specify parameters for energy metabolism and neuronal damage.

 

No significant differences were detected for 1H detectable metabolites total creatine (tCr) and N-acetylaspartate (tNAA).  However, 31P MRS showed a significant decrease of inorganic phosphate (Pi), phosphocreatine (PCr), and ATP in the basal ganglia while in the occipital cortex only ATP was reduced. Lactate was never detected in controls but in approximately 20% of the patients. Calculation of ADP and the phosphorylation potential (PP) using standard equilibrium constant for creatine kinase  yielded no differences between patients and controls. This indicates that reduced mitochondrial activity is compensated by reduction of ATP and inorganic phosphate leaving the PP constant, which may account for the rather mild decrease in tNAA. The decrease of phosphometabolites like ATP and Pi should be a marker of the severity of the disease and potential effects of treatment.

 

15:00         3455.     Adults with Significant Childhood Lead Exposure Evaluated with Proton MR Spectroscopy

Computer 48

Kim M. Cecil1, Kim N. Dietrich2, Mekibib Altaye1, John C. Egelhoff1, Stephanie D. Wessel2, Bruce P. Lanphear1

1Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA; 2University of Cincinnati, Cincinnati, Ohio, USA

We hypothesized that adults with childhood lead exposure would demonstrate evidence of irreversibly altered neural metabolism. Participants (N=159) of a longitudinal birth cohort studying the effects of lead exposure completed a quantitative, short echo spectroscopy protocol evaluating seven brain regions. Higher mean childhood blood lead levels were associated with reduced metabolite concentrations upon adjusting for age at time of imaging and full scale intelligence quotient. Gray matter reductions of N-acetyl aspartate are consistent with the concept that sustained childhood lead exposure results an irreversible, pattern of injury consistent with an insult from childhood. White matter choline changes suggest an alteration to the myelin structure. These neural alterations may be responsible for the cognitive and behavioral changes attributed to lead exposure.

 

Pediatric Brain: DTI, Structural

Hall D                                   Tuesday 13:30-15:30                                                                                                                                             

13:30         3456.     Application of a Fast High Resolution Whole Brain MRI for Segmentation

Computer 49

Ying Wu1,2, Dunkle Eugene1, Andres Carrillo1, Ann Ragin2, Robert Edelman1,2

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

MRI segmentation and visualization have gained increasing importance

 both in research and clinical applications.  The conventional MR sequence, FSPGR (or MP-RAGE), has been widely utilized in MR segmentation and in clinical fMRI because its contrast behavior is suitable for segmentation and this sequence can provide thin slice whole brain coverage.  In this investigation, we present a fast whole brain high resolution MR technique, EZ Step (EZ).  Images generated with the sub-milliliter isotropic EZ Step sequence have similar GM/WM contrast behavior as FSPGR.  Available automated segmentation utilities, such as FSL and Freesurfer, can be adapted for EZ.  Moreover, EZ has higher CNR than FSPGR in basal ganglia and other clinically significant regions of interest.EZ can also be used to derive superior quality brain volume rendering for fMRI applications, while reducing data acquisition scan time of current clinical routines by 40%.

 

 

14:00         3457.     Regionally Specific Cortical Thinning in Paediatric Sickle Cell Disease [Not Available]

Computer 49

Richard Alan Jones1,2, Gregory Kirk3, Michael Ryan Haynes4, Susan Palasis5, Clark Brown6

1Children's Healthcare of Atlanta, Atlanta, Georgia, USA; 2Emory University, Atlanta, Georgia, USA; 3Children's Healthcare of Atlanta, Atlanta, USA; 4Georgia Institute of Technology, Atlanta, USA; 5Ch

Cortical thickness was compared in control and sickle cell paediatric subjects using Freesurfer. The groups were split into two components by age; The first group consisted of all subjects< 12 years of age, and the second group all subjects >=12 years of age. Separate group analyses were performed on each of the two groups. In the younger group relatively few differences were found, while in the older group more extensive areas of bilateral thinning were found in the sickle cell subjects, suggesting that their gray matter is abnormal and that the amount of thinning is age dependent.

 

14:30         3458.     Treatment-Induced Plasticity in Central Motor Pathways in Cerebral Palsy: Diffusion Tensor Imaging

Computer 49

Rakesh K. Gupta1, Richa Trivedi1, Vipul Shah, Mukesh Tripathi1, Ram KS Rathore2, Manoj Kumar1, Ponnada A. Narayana3

1Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India; 2Indian Institute of Technology, Kanpur, India; 3University of Texas Medical School at Houston, Houston, USA

Serial diffusion tensor imaging (DTI) was performed on eight pediatric patients with cerebral palsy (CP) at the time of diagnosis and after 6 months of botulinum treatment followed by intensive physiotherapy. Region of interests were placed on corticospinal tracts at the level of corona radiate (CR), posterior limb of internal capsule (PLIC), mid brain (MB), pons, and medulla in patients as well as controls. On 6 month follow-up significantly increased FA values were observed in CST at the level of CR, PLIC, and MB compared to baseline study. The observed increase in FA along with improved clinical motor score suggests plasticity of the central motor pathway following the combined therapy.

 

15:00         3459.     Correlation of Brain Diffusion Tensor Imaging Metrics with Cognitive Functions in Patients of Spina Bifida Cystica

Computer 49

Manoj Kumar1, Rakesh Kumar Gupta1, Mazhar Husain2, Sanjay Behari1, Gyanendra K. Malik2, S N. Kureel2, Richa Trivedi1, Ram Kishore Singh Rathore3

1Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India; 2CSMM University, Lucknow, India; 3Indian Institute of Technology, Kanpur, India

Neural tube defect during early pregnancy affects the normal brain development and leads to deficits in cognitive functions and memory. DTI and battery of neuropsychological test (NPT) were performed in 19 SBC patients and controls.  ROIs were placed in different region of the brain including deep gray matter [caudate nuclei (CN), thalamus (Th) and putamen (P)] and white matter corticospinal tracts (CST), and cingulum (Cing), fornix, genu and splenium (Spl) in SBC patients as well as controls. The spearman rank correlations between FA, MD and NPT scores were performed in patients and controls. Our observations demonstrated that significant correlation between FA and MD values with FCT score in genu of CC, and significant correlation between FA values in cingulum and NCT B scores which reflects the deficits in learning, memory and timing functions. The FA values in CST are correlated with PAT scores suggesting the deficits in sensory and motor functions.

 

13:30         3460.     Temporal Brain White Matter Maturation in Spina Bifida Cystica (SBC) with Diffusion Tensor Imaging

Computer 50

Manoj Kumar1, Rakesh K. Gupta1, Richa Trivedi1, Mazhar Husain2, Sanjay Behari1, Gyanendra K. Malik2, S N. Kureel2, Ram KS Rathore3, Ponnada A. Narayana4

1Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India; 2Chhatrapati Sahuji Maharaj Medical University, India; 3Indian Institute of Technology, Kanpur, India; 4University of Texas Medical Scho

DTI was performed in 23 SBC patients along with 33 age/sex matched controls. ROI were placed in corpus callosum [genu and splenium (Spl)], internal capsule [anterior limb of internal capsule (ALIC), posterior limb of internal capsule (PLIC)], periventricular WM [frontal white matter (FWM), occipital white matter (OWM)] and corticospinal tracts (CST) at the level of pons in SBC patient as well as controls. Different pattern of FA changes in major WM tracts in SBC patients compared to controls demonstrate that the pattern of brain WM in SBC is different from normal development. In SBC patient’s significant reorganization was observed at structural and functional levels during the development.

 

MRI: ENT Imaging

Hall D                                   Wednesday 13:30-15:30                                                                                                                                       

13:30         3461.     Average Arterial Input Function and Quantitative Dynamic Contrast Enhanced (DCE)-MRI of Nodal Metastases in the Neck

Computer 38

Amita Shukla-Dave1, Nancy Lee1, Hilda Stambuk1, Ya Wang1, Wei Huang1, Jason A. Koutcher1

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

Nine patients with nodal metastases in the neck underwent dynamic contrast enhanced MRI (DCE-MRI) studies on a 1.5T clinical MRI scanner. Reliable Individual Arterial Input Function AIF (Ind-AIF) were obtained from all the patients and an average-AIF (Avg-AIF) was calculated. No statistical differences were seen in pharmacokinetic parameters obtained with Ind-Avg and Avg-AIF. The present study builds Avg-AIF in patients with nodal disease in the neck which may be useful in large patient population studies, e. g. in clinical trials to examine the effects of drugs on Ktrans and ve or in situations where Ind-AIF cannot be obtained.

 

14:00         3462.     Perfusion Characteristics of Radiation-Induced Parotitis: Quantitative Evaluation with Dynamic Contrast-Enhanced MRI

Computer 38

Hua-San Liu1,2, Chun-Jung Juan2, Hsiao-Wen Chung1, Cheng-Yu Chen2, Yee-Min Jen2, Chao-Ying Wang1,2, Chun-Jen Hsueh2, Chung-Ping Lo2, Guo-Shu Huang2

1National Taiwan University, Taipei, Taiwan; 2Tri-Service General Hospital, Taipei, Taiwan

Radiation-induced parotid gland injury degrades the life quality of patients who ever receive radiotherapy for treating head and neck cancer. Conventional MR imaging of the irradiated parotid glands only shows intense parotid enhancement. Applying the non-linear least square curve fitting algorithm to the Brix pharmacokinetic model, the perfusion parameters of the irradiated parotid glands were quantified. The irradiated parotid glands showed significantly lower Kel (P < 0.0005), marginally lower k21 (P < 0.05) and unaltered A (P = 0.26) compared with non-irradiated ones, suggestive of gradual and prolonged accumulation and delayed wash-out of contrast agent in the irradiated glands rather than increased vascular permeability.

 

14:30         3463.     Comparison of Diagnostic Performance Between MRI Including Diffusion-Weighted Imaging and FDG-PET/CT in Patients with Head and Neck Cancer [Not Available]

Computer 38

Yuji Nakamoto1, Tomohisa Okada1, Yasuyo Hamanaka2, Kohei Hayashida2, Kaori Togashi1

1Kyoto University Hospital, Kyoto, Japan; 2Takeda Oncologic Positron Imaging Center, Kyoto, Japan

We have compared the diagnostic performance of MRI including diffusion-weighted imaging and FDG-PET/CT in patients with head and neck cancer. For detecting primary tumors or metastatic cervical lymph nodes, the patient-based sensitivity and specificity of MRI were comparable with those of FDG-PET/CT.

 

15:00         3464.     Therapeutic Response Assessment Using Dynamic Contrast-Enhanced MR Imaging in Patients with Differentiated Thyroid Carcinoma: An Initial Study at 3T [Not Available]

Computer 38

Jiachao Liang1, Steffen Sammet1, Xingyu Yang1, Guang Jia1, Zarine Shah1, Regina Koch1, Manisha Shah1, Michael V. Knopp1

1The Ohio State University, Columbus, Ohio, USA

Therapy monitoring of differentiated thyroid carcinoma using DCE-MRI at 3T provides a capability for evaluating the biologic therapeutic responses by a clinically readily available approach.

 

13:30         3465.     Monitoring Response to Chemoradiation Therapy of Squamous Cell Carcinomas of the Head and Neck Using Diffusion Weighted MRI
[Not Available]

Computer 39

Sungheon Kim1, Laurie A. Loevner1, Harry Quon1, Eric J. Sherman1, Gregory S. Weinstein1, Harish Poptani1

1University of Pennsylvania, Philadelphia, USA

The purpose of this study was to investigate the feasibility of using apparent diffusion coefficient (ADC) for early detection of treatment response in squamous cell carcinomas of the head and neck (HNSCC). DW-MRI studies were performed with 32 patients before, during, and after the end of treatment. Pre-treatment ADC of complete responders (CR) was significantly lower than that of partial responders (PR). A significant increase in ADC was observed in the CR group within one week of treatment and remained high until the end of the treatment. These results suggest that ADC can be used as a predictive marker for therapeutic response in HNSCC.

 

14:00         3466.     Monitoring Therapeutic Effect of Cetuximab in the Treatment of Nasopharyngeal Carcinoma by DCE-MRI

Computer 39

Francis Kar Ho Lee1, Brigitte Ma1, David Ka Wai Yeung1, Ann Dorothy King1

1the Chinese University of Hong Kong, Hong Kong, People's Republic of China

Dynamic contrasted enhanced MRI is becoming a popular technique to evaluate the therapeutic effect of anti-angiogenic and anti-vascular drugs for the treatment of cancers. The potential of the technique to predict treatment outcome is attractive as it can provide valuable information for treatment planning. In this study, we attempted to use this technique to monitor the therapeutic effect of cetuximab, an epidermal growth factor receptor (EGFR) inhibitor, in the treatment of nasopharyngeal carcinoma (NPC). The effect of this drug in combination with chemotherapy for NPC has been published, while this report describes the preliminary attempt to examine the potential of the DCE technique in the early detection of drug response.

 

14:30         3467.     Serial MRI Study of Delayed Brain Injury Induced by Radiotherapy Treatment for Nasopharyngeal Carcinoma

Computer 39

Yi Xiang Wang1, H Zhou2,3, A D. King2, J Abrigo2, Y L. Chan2, D K. Yeung2

1The Chinese University of Hong Kong, Prince of Wales Hospital , Shatin, People's Republic of China; 2The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, People's Republic of China; 3First Affiliated Hos

Radiation induced injury (RI) of temporal lobe is a late complication of radiation therapy for nasopharyngeal carcinoma (NPC). This study investigates the temporal changes of RI in the temporal lobe with serial MRI. This is a retrospective study of 77 consecutive patients. These patients had known RI of the temporal lobes due to RT on MR with at least one further follow up MR for analysis. Our results demonstrated that the RI lesions can remain static, increasing, decreasing or resolve, but overall the RI appears to demonstrate an initial developing phase and later resolving phase.

 

15:00         3468.     High Resolution Non-Contrast Lymphangiography of the Head and Neck at 3Tesla

Computer 39

Ravi Teja Seethamraju1, Yiu Cho Chung2, Jaeseok Park3, Graham C. Wiggins4, Mukesh G. Harisinghani5, Denise Hinton-Yates4

1Siemens Medical Solutions USA, Inc., Charlestown, Massachusetts, USA; 2Siemens Medical Solutions USA, Inc., Columbus, Ohio, USA; 3Siemens AG., Erlangen, Germany; 4Athinoula A. Martinos Center for Biomedical Ima

A state of the art non-contrast T2 weighted TSE  3D sequence for Lymphangiography of the head and neck is presented here. This sequence can detect lymph nodes with 3D isotropic sub-millimeter resolution in a distinct manner. This is a major advantage over traditional 2D TSE methods where the through plane resolution is low thereby increasing the chance of missing small lymph nodes that are less than 5mm. Currently this method can distinctly show all nodes with high contrast immaterial of the nodal status. When combined with nano-particle enhanced contrast agents this techniques has the potential to be sensitive to metastasis.

 

13:30         3469.     Comparison of Duplex Sonography and High Resolution MRI [Not Available]

Computer 40

Thorsten Alexander Bley1,2, Mathias Reinhard1, Carolin Hauenstein1, Michael Markl1, Klaus Warnatz1, Mathias Langer1

1University of Freiburg, Freiburg, Germany; 2University of Wisconsin - Madison, Madison, USA

Giant cell arteritis (GCA) is a chronic vasculitis of large and medium sized arteries. Temporal atery bopsy (TAB) is considered the diagnostic gold standard. Noninvasive diagnosis of GCA is a challenge. The purpose of this study was to to compare the diagnostic performance of high resolution (196µm × 260µm) magnetic resonance imaging (MRI) and color coded duplex sonography (CCDS) in patients with GCA. Sensitivity of MRI (CCDS) compared with TAB was 83% (79%), specificity 71% (59%), NPV 80% (73%) and PPV 75% (67%). Larger trials are warranted to investigate the potential of noninvasive imaging to replace temporal artery biopsy.

 

14:00         3470.     Real Time Sleep MRI and Physiologic Monitoring of Patients with Obstructive Sleep Apnea

Computer 40

Andrew B. Holbrook1,2, Jose Barrera1, Juan M. Santos1, Kim Butts Pauly1, Gerald Popelka1

1Stanford University, Stanford, California , USA

Obstructive sleep apnea (OSA) is a serious and dangerous disorder that could benefit from improved diagnosis with MRI.  In this study, ten patients with mild to severe OSA were imaged continuously in real-time in an interventional 0.5T magnet while also monitoring physiological conditions using a WatchPat WP100 OSA testing device.  Physiological data were registered to acquired images.  Imaging showed locations of airway obstructions, with physiologic data showing signs of possible respiratory events (changing pulse arterial tone amplitude, decreasing oxygen saturation).  Such results could be useful in improving patient diagnosis and resultant care.

 

MRI & MRS of Epilepsy

Hall D                                   Wednesday 13:30-15:30                                                                                                                                       

13:30         3471.     Distribution of Neurochemical Changes in Narcoleptic Patients with Cataplexy: A Proton MR Spectroscopy Study

Computer 41

Caterina Tonon1, Raffaele Lodi1, Giuseppe Plazzi1, Christian Franceschini1, Claudia Testa1, David Neil Manners1, Pasquale Montagna1, Bruno Barbiroli1

1University of Bologna, Bologna, Italy

The pathophysiology of narcolepsy with cataplexy (NC), a rare underdiagnosed sleep disorder, is as yet only partially defined. Investigations using various neuroimaging techniques of brain structures suspected to be involved in sleep/awake regulation have given contradictory results. In the present study of 21 NC patients using 1H-MRS we demonstrated evidence of neuronal loss in the hypothalamus, while no significant biochemical changes were found in the thalamus and the parietal-occipital cortex. Advanced MR techniques may contribute to the clarification of the pathophysiological mechanisms of NC, and hence to the development of targeted pharmacological options. 

 

14:00         3472.     Hippocampal Neurotransmitter Imbalance and the Role of GS in Epileptogenesis; a Longitudinal in vivo MRS and Histochemical Study in a Juvenile Model of Temporal Lobe Epilepsy

Computer 41

Pieter van Eijsden1, W Saskia van der Hel1, Ineke W. M. Bos1, Robin A. de Graaf2, Kevin L. Behar2, Onno van Nieuwenhuizen1, Pierre N.E. de Graan1, Kees P.J. Braun1

1University Medical Center Utrecht, Utrecht, Netherlands; 2Yale University, New Haven, USA

Epileptogenesis in temporal lobe epilepsy has been associated with a disturbance of hippocampal glutamatergic and GABAergic neurotransmission. To characterize this disturbance, we combined in vivo MRS with immunohistological methods at two time points during the latent phase of the juvenile lithium pilocarpine rat model. Reductions in NAA and increases in Cho indicate neuronal death and gliosis, which is confirmed by FJ and Vim staining. GABAergic neurons are most affected, leading to a hyperexcitable state. After an initial increase, glutamine normalizes, which is explained by reduced GS immunoreactivity. These findings represent relevant pre-epileptic changes, which serve as markers of imminent epilepsy.

 

14:30         3473.     Metabolic Connectivity in Controls and Epilepsy Patients

Computer 41

Jullie Pan1, Susan Spencer, Ruben I. Kuzniecky2, Dennis Spencer1, Hoby Hetherington1

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

The goal of this study was to evaluate the pattern and extent to which the correlated reductions in NAA from the hippocampus thalamus, putamen and insula define a unique network of impairment which can resolve mesial temporal lobe epilepsy (mTLE) from neocortical epilepsy (NE). MRSI measurements of NAA were acquired from the hippocampus, thalamus, putamen and insula of controls (20), mTLE (27) and NE (18) patients. Significant differences in NAA distributions throughout these neuronal networks were  between controls and patients with epilepsy and mTLE and NE patients.

 

15:00         3474.     First Clinical Epilepsy Imaging at 7 Tesla

Computer 41

Tobias Breyer1, Jens M. Theysohn2, Stefan Maderwald2, Oliver Kraff2, Marc Ladd2, Friedrich Woermann3, Alois Ebner3, Marc U. Schlamann1, Michael Forsting1, Isabel Wanke1

1Essen University Hospital, Essen, Germany; 2University of Duisburg-Essen, Essen, Germany; 3Bethel Epilepsy Center, Bielefeld, Germany

Even very subtle cortical lesions can cause severe epileptic syndromes. High magnetic field MR-imaging at 7 Tesla therefore promises better signal-to-noise ratio and spatial resolution for improved lesion depiction and subsequently selection of more possible treatment options for affected patients. We investigated -for the first time- patients with known epileptic lesions, either hippocampal sclerosis or focal cortical dysplasia- at 7 Tesla with spin-echo PD-/T2-, T1- as well as T2*-weighted sequences.

 

13:30         3475.     Mapping Hippocampal Activity During Epileptogenesis by Manganese Enhanced Magnetic Resonance Imaging(MEMRI)

Computer 42

Ke Fang1, Stefanie Dedeurwaerdere1, Yutang Shen1, Terence J. O'Brien1, Gary F. Egan1

1University of Melbourne, Melbourne, Australia

This longitudinal study aims to characterise the progressive pathological changes in the hippocampus of the post-kainic acid status epilepticus (SE) rat model of temporal lobe epilepsy using MEMRI in vivo. .  A progressive increase in signal intensity was found in the hippocampus in the epileptic group compared to the control group , which indicated more neuronal activities in hippocampus in the epilepsy KA model. Early changes in the dentate gyrus also significantly correlated with seizure outcome at a later stage, which may have implications for predicting seizure phenotype.

 

14:00         3476.     Voxel Based Morphometry and Statistical Parametric Mapping of Positron Emission Tomography (SPM-PET) in Patients with Juvenile Myoclonic Epilepsy Compared to Normal Controls [Not Available]

Computer 42

Long Vu1, Barbara Swartz2, Mark Mandelkern1, Orhan Nalcioglu1, Min-Ying Su1

1University of California, Irvine, USA; 2Hoag Hospital, Newport Beach, USA

Voxel Based Morphometry (VBM) and Statistical Parametric Mapping of Positron Emission Tomography (SPM-PET) were performed to analyze the differences in brain morphology and PET activity between 18 JME patients and 16 Controls. VBM results showed that JME had more gray matter than Controls in the caudate, cingulate, temporal, and frontal regions. SPM-PET showed that Controls had more glucose uptake than JME in the frontal regions. These findings suggest that VBM and PET may provide complementary structural and functional information. Along with EEG, they might be useful to differentiate between FLE and JME patients.

 

14:30         3477.     Diffusion Tensor Imaging in Lateralising and Localising Epileptogenic Focus in Temporal Lobe Epilepsy with and Without Hippocampal Sclerosis

Computer 42

Siew-Min Gan1, Willy Handoko, Soren Christensen, Patricia Desmond, Terence O'brien

1Royal Melbourne Hospital, Univeristy of Melbourne, Melbourne, Australia

Diffusion Tensor Imaging and volumetric changes are compared between Temporal Lobe Epilepsy patients with Hippocampal Sclerosis (HS+ve) and patients with no structural changes on standard MRI (HS-ve). In addition to ADC and FA, the p,q, and L derivatives of the tensor will be explored to quantify anisotropy changes in the hippocampus and the anterior temporal pole gray matter and white matter, with the aim to determine if DTI can localise the epileptogenic region in the subtypes of TLE and whether the DTI changes are independent of the structural changes of hippocampus sclerosis.

 

15:00         3478.     Thalamocortical Atrophy in Patients with Primary Generalized Tonic and Clonic Seizures [Not Available]

Computer 42

Boris Christian Bernhardt1, Daniel Rozen2, Linda Horwood2, Andrea Bernasconi1

1Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada; 2Brain Imaging Center, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada

Although previous work in idiopathic generalized epilepsy (IGE) indicates that the thalamocortical circuitry is involved in the generation of the epileptic discharges, the neuropathological substrate of IGE is not fully defined. We measured cortical thickness and calculated the volumes of thalami on high-resolution MRI in IGE patients and healthy controls. In IGE, fronto-centro-parietal areas and the thalamus were bilaterally atrophic. Thickness in the same cortical regions had a high positive correlation with thalamus volumes. Duration of epilepsy negatively affected thalamus volumes and thickness in centro-parieto-occipital areas. Our results therefore demonstrate bilateral and progressive atrophy in thalamocortial networks in IGE.

 

13:30         3479.     Building a 3D Atlas of the Human Hippocampus from Postmortem Magnetic Resonance Imaging

Computer 43

Paul A. Yushkevich1, John Pluta1, Brian B. Avants1, David Minkoff1, Stephen Pickup1, Weixia Liu1, John A. Detre1, Murray Grossman1, James C. Gee1

1University of Pennsylvania, Philadelphia, Pennsylvania, USA

High resolution 9.4 Tesla imaging of the human hippocampus in vitro is performed in order to build a three-dimensional atlas of the structure. The atlas will serve as a model of hippocampal substructure for in vivo MRI studies of memory and neurodegenerative disorders.

 

Brain Tumor: Perfusion & Diffusion & fMRI

Hall D                                   Wednesday 13:30-15:30                                                                                                                                       

14:00         3480.     A Comparison of Enhancing Fraction and DCE-MRI Parameters in Glioma of Various Grade

Computer 43

Samantha Jane Mills1, Calvin Soh2, Giovanni Buonaccorsi1, James Patrick Bernard O'Connor1, Susan Cheung1, Sha Zhao1, Geoffrey James Martin Parker1, Alan Jackson1

1University of Manchester, Manchester, UK; 2Hope Hospital, Salford, UK

This study compares the proportion of enhancement of a tumour, enhancing fraction, with more complexly derived DCE-MRI parameters of blood volume (vp), contrast transfer coefficient (Ktrans) and the extra-vascular extracellular volume (ve) for a variety of cerebral gliomas of various histological grade. The relationship of these parameters with enhancing fraction is dependent upon tumour grade; in low grade tumours enhancing fraction relates to vp whilst in high grade tumours it relates to Ktrans. This is most likely a result of differences in the integrity of the blood brain barrier seen in tumours of different grade.

 

14:30         3481.     Valuation of Brain Tumours with MRS and PWI-DSC. Use of a Non Parametric Method in the Post Processing of PWI-DSC

Computer 43

Salvador Olmos1, Nicolas Nicolas Fayed2, Jorge Humberto Davila 2

1Universidad De Zaragoza, Zaragoza, Spain; 2Hospital Quiron, Zaragoza, Spain

High grade Brain tumors are highly vascularizated. These changes can be easily detected in Perfusion studies; however, as happen in our study sometimes a low vascularity is described. This could be explained by a loose of contrast trough the rupture of the BBB described in high grade tumors. Using a new non parametric method in the post processing of PWI-DCI we look for a better valuation of this phenomenon, that will allows us to have a better tool in the diagnosis of high grade tumors. However, at the moment the best tool for in the diagnosis of brain tumors is MRS.

 

13:30         3482.     Validation of a Standardization Technique for Brain Tumor RCBV Maps and Post-Contrast Anatomic Images

Computer 44

Devyani P. Bedekar1, Todd Jensen2, Eric Paulson1, Kathleen M. Schmainda1

1Medical College of WI, Milwaukee, Wisconsin, USA; 2Jensen Bioinformatics, New Berlin, Wisconsin, USA

Relative cerebral blood volume (rCBV) measurements for the same tissue type suffer from interpatient and interstudy variability. As a result, CBV values are commonly normalized to a chosen reference region of interest (ROI) such as white matter (WM).  But this technique of normalization is subjective and thus introduces user-dependent variability, and is time-consuming and therefore unlikely to become part of the routine evaluation of longitudinal studies.  In this study we demonstrate that standardization of the perfusion values to a consistent scale is at least as good as normalization to a reference ROI.  Furthermore, we validate that standardization does not alter the informational content of the image.  Thus, standardization enables fast, objective and accurate visual comparison across studies and can be employed with ease in the radiology workflow to longitudinally assess brain tumor progression and response to therapy.

 

14:00         3483.     Comparison of Quantitative Blood Flow Values  from DCE- And DSC-Based Perfusion in Glioblastoma Multiforme and Cerebral Tissue
[Not Available]

Computer 44

Martine Isabella Dujardin1, Steven Sourbron2, Rob Luypaert1, Cristo Chaskis1, Smitha Makkat1, Tadeusz Stadnik1, Johan de Mey1

1UZ Brussel, Brussels, Belgium; 2Klinikum Grosshadern, Munich, Germany

In this study, we compare CBF values in glioblastoma multiforme and contralateral white and grey matter from T1-DCE-based [CBFT1] and T2*-DSC-based [CBFT2*] perfusion, as well as lesion-to-normal-white matter CBF ratios from both techniques. CBFT2*  measures were systematically higher compared to CBFT1 and CBF measures from both techniques did not show correlation. DSC-MRI CBF values may be reliable when normalized to a reference tissue type. However, since values of CBFT1 are  more in line with the findings for grey and white matter CBF from PET, DCE-based perfusion measures of CBF seem to be preferable in tumor perfusion work-up and follow up.  

 

14:30         3484.     A Comparison of DCE-MRI Derived Measure of Extracellular Volume and ADC in Glioblastoma Multiforme

Computer 44

Samantha Jane Mills1, Calvin Soh2, Chris Rose1, Susan Cheung1, Sha Zhao1, Geoffrey James Martin Parker1, Alan Jackson1

1University of Manchester, Manchester, UK; 2Hope Hospital, Salford, UK

DCE-MRI provides quantification of the volume of the extravascular extracellular space (ve). An inverse linear relationship between the apparent diffusion coefficient (ADC) and histological measures of cell density has been previously shown in glioma. We proposed that areas of increased cell packing (and low ADC) would have small extracellular volumes (and low ve). No relationship was found between ADC and ve in this study of high grade glioma. This failure of correlation may be due to a number of factors including co-registration issues, partial volume effects, tumour heterogeneity, and abnormalities in cell membrane permeability dictated by the underlying pathology.

 

15:00         3485.     Quantifying the Proportion of Enhancement in Relation to IAUC Thresholds; a Comparison with Other Measures of Enhancement in Adult Gliomas

Computer 44

Samantha Jane Mills1,2, Calvin Soh2, Susan Cheung1, James Patrick Bernard O'Connor1, Sha Zhao1, Geoffrey James Martin Parker1, Alan Jackson1

1University of Manchester, Manchester, UK; 2Hope Hospital, Salford, UK

This study details different methods for assessing the proportion of tumour enhancement in gliomas of various grade, in relation to IAUC values. We describe an optimum technique for separating tumour grade and detail how this compares to other previously described methods of assessing enhancement based upon signal intensity.

 

13:30         3486.     Longitudinal Assessment of Avastin Therapy Using Biological Response Indicator Perfusion Maps: Predicting Response to Therapy

Computer 45

Melissa Lynne Wagner-Schuman1, Devyani Bedekar1, Eric S. Paulson1, Doug E. Prah1, Kathleen M. Schmainda1

1Medical College of Wisconsin, Milwaukee, Wisconsin, USA

The study of tumor angiogenesis for the diagnosis of gliomas has potential benefits in therapeutic management. With the recent clinical trials of anti-angiogenic agents, the necessity for angiogenesis biomarker development has become apparent. In this study we employed a noninvasive imaging technique, DSC-MRI to estimate relative cerebral blood volume and, with the aide of longitudinal registration, created functional cerebral blood volume (fCBV) maps in patients receiving Avastin. The fCBV maps correlated with patient response to treatment giving insight into treatment effectiveness. This study demonstrates longitudinal registration and creation of fCBV maps used to monitor tumor biology and predict therapeutic response.

 

14:00         3487.     "Hot Spot" Analysis for Glioblastoma Multiforme

Computer 45

Priscilla Yeo1, Poe J. Chen1,2, Weiting T. Zhang1, Emmanuelle di Tomaso1, Dan G. Duda1, Rakesh K. Jain1, Tracy T. Batchelor1, Alma G. Sorensen1

1Massachusetts General Hospital, Charlestown, Massachusetts, USA; 2Massachusetts Institute of Technology, Cambridge, Massachusetts, USA

Past studies indicate that there is value in using tumor areas with the highest density of distinctly highlighted microvessels (“hot-spots”) as a prognostic indicator for various cancers. Here, we suggest using a spatial method of locating hot-spots in glioblastoma ROIs to predict survival outcomes of GBM patients.

 

14:30         3488.     Extravascular Enhancement with a Blood-Pool Contrast Agent - A New Class of Contrast in Magnetic Resonance Imaging

Computer 45

Marco Essig1, Matthias Voth2, Martin Rohrer2, Frederik Giesel1

1German Cancer Research Center, Heidelberg, Germany; 2Bayer Schering, Berlin, Germany

We present the first study that shows the potential of the protein-binding blood-pool contrast agent gadofosvest trisodium (Vasovist®) for high quality contrast enhanced MR imaging of various cerebral tumors. Even at an early time point a robust enhancement could be observed with a substantially lower amount of Gadolinium-chelate.  Furthermore, based on previous experience in animal models one might expect an even more effective contrast at a later time point after administration.

Further controlled studies are ongoing to assess the clinical potential of these agents as well as the advantage over the currently established MR contrast agents.

  

15:00         3489.     Detection of Early Response After Radiosurgery for Vestibular Schwannoma Using an Eigen Vector Based Approach

Computer 45

Yu-Chun Lin1,2, Chun-Chieh Wang2, Koon-Kwan Ng2, JiunJie Wang1,2

1ChangGung University, KweiShan, Taiwan; 2ChangGung Memorial Hospital, KweiShan, Taiwan

This study prospectively examined the changes of directional coherence of vestibular schwannoma (VS) at an acute stage of after stereotactic radiosurgery (SRS) treatment. An eigenvector based index, intervoxel diffusion coherence (IVDC), was calculated, which described the coherence in the distribution of the white matter tracts in a voxel and its neighborhood. The results showed the IVDC increased significantly immediately after the treatment while FA remained stable throughout the period of investigation. Therefore IVDC is more sensitive than FA in early detection of the response to the SRS treatment for VS patients.

 

13:30         3490.     A Tract-Based Spatial Statistics Study of White Matter Compromise in Pediatric Brain Tumor Patients Treated with Cranial Radiation

Computer 46

Donald Mabbott1,2, Conrad Rockel1, Eric Bouffet1,2

1The Hospital for Sick Children, Toronto, Canada; 2University of Toronto, Toronto, Canada

We examined differences in FA for children treated with CRT relative to control subjects using tract-based spatial statistics (TBSS) to determine whether these differences are diffusely present across all regions of the brain or localized to specific regions.  Reduced FA in patients treated with CRT was evident relative to healthy controls across multiple regions, including the corpus callosum, internal capsule, cortico-spinal tracts, and hemispheric white matter. Using a tract-based spatial statistics methodology, we documented compromised white matter integrity in patients treated with CRT relative to controls.  These differences were diffuse and there was no evidence of regional variation in FA differences between patients and controls.

 

14:00         3491.     Differentiation Between Glioblastoma and Brain Metastasis Using Diffusion Tensor Imaging

Computer 46

Sumei Wang1, Sungheon Kim1, Sanjeev Chawla1, Wei Guo Zhang1, Ronald L. Wolf1, Donald M. O'Rourke1, Kevin D. Judy1, Elias R. Melhem1, Harish Poptani1

1University of Pennsylvania, Philadelphia, Pennsylvania, USA

In addition to conventional DTI metrics, ADC and FA, tensor shape measures such as linear and planar anisotropy coefficient (CL and CP) were used in this study to differentiate between glioblastoma and solitary brain metastasis. Forty glioblastoma and 19 brain metastasis patients underwent DTI studies at 3T. CL, CP, FA and ADC were measured from the enhancing part as well as peritumoral regions. CL, CP and FA values of the enhancing part in glioblastomas were significantly higher than those in metastases. These results indicate that DTI metrics including shape-oriented measures may be helpful in differentiating glioblastomas from brain metastases.

 

14:30         3492.     Repeatability of Apparent Diffusion Coefficient and Fractional Anisotropy in Patients with Recurrent Glioblastoma Multiforme

Computer 46

Michael John Paldino1, Dhiral Phadke1, Annick DesJardins1, James Vredenburgh1, Henry Friedman1, Daniel P. Barboriak1

1Duke University Medical Center, Durham, North Carolina, USA

This study analyzes the repeatability of diffusion tensor imaging in patients with high grade glioma.  These results provide a context within which to interpret changes in diffusion parameters that occur after treatment.

 

15:00         3493.     Serial Diffusion Tensor Imaging to Characterize Radiation Induced Changes in Normal Appearing White Matter Following Radiotherapy in Patients with Adult Low Grade Gliomas (WHO Grade II)

Computer 46

Shaleen Kumar1, Mohammad Haris1, Ankur Purwar2, Mani Kartick Raj1, KJ Maria Das1, Sanjay Behari1, Ram Kishore Singh Rathore2, Rakesh Kumar Gupta1

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

Quantitative evaluation of changes in normal appearing white matter (NAWM) of brain tumor patients receiving radiotherapy (RT) have been described using DTI metrics i.e. fractional anisotropy (FA) and mean diffusivity (MD). However, data on DTI metrics in NAWM irradiated to varying doses are scarce and in one recent study, confounded by the addition of chemotherapy to RT. Besides FA and MD, other DTI metrics i.e., linear case (CL), planar case (CP) and spherical case (CS) may provide additional information associated with WM injury. This study assessed the utility of various DTI metrics to characterize the threshold for detection and temporal evolution of changes in NAWM of adults with low grade glioma treated with RT. We found that upto 14-months following RT, the threshold of detection of radiation changes using FA, CL and CS is 45-50Gy while it was 50-55Gy when using MD and CP.

 

13:30         3494.     Preliminary Results of the Effects of Higher Order Reconstruction on Diffusion MRI Data on Our Predictive Model for Tumor Recurrence

Computer 47

Anitha Priya Krishnan1, Sharmistha Chaudhuri1, Delphine Davis1, Paul Okunieff1, Walter G. O'Dell1

1University of Rochester, Rochester, USA

Our goal is to modify the treatment margin for Stereotactic Radiotherapy of primary brain tumors in accordance to our hypothesis that the tumor cells tend to migrate along the paths of elevated water diffusion. Previously we implemented a random walk model to predict migration of cancer cells constrained by the local diffusion environment. Here we compare the results of our random walk model based on one tensor reconstruction with the model based on multi tensor reconstruction of DTI data. The hypothesis is that the multi-tensor reconstruction will better simulate the cell migration pattern in areas of fiber crossing.

 

14:00         3495.     A Longitudinal Study of the Cortical Reorganization of Language Function in Brain Tumor Patients

Computer 47

Kyung K. Peck1, Nicole Brennan, Bob Hou, Andrei Holodny1

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

The purpose of this longitudinal study is to measure the dynamic changes in language organization in brain tumor patients over time in an effort to better understand the mechanism underlying cortical adaptation.

Brain tumor patients with a low grade tumor directly adjacent to the language centers, were enrolled. The fMRI paradigm is designed to engage language related areas including Broca¡¯s area. Statistical parametric maps of pre-surgical, 3 months post-surgery and 6 months post-surgery fMRI language mapping supports the inter-hemispheric mechanism of cortical compensation in brain tumor patients.

 

14:30         3496.     Spectral Analysis of Hemodynamic Response Delays in Brain Tumor Patients

Computer 47

Johan N. van der Meer1, Sanna Gevers1, Charles B. Majoie1, Marina A. Tijssen1, Aart J. Nederveen1

1Academic Medical Centre, Amsterdam, Netherlands

Hemodynamic response delay times are assessed near tumor tissue using spectral analysis (SA) of fMRI time series. The presence of tumors can drastically alter this response time. Using SA, activation is measured near tumors where the GLM shows nothing. By using this method, the number of 'false negative' voxels are reduced.

 

15:00         3497.     Quantification of False Negative BOLD Response; Functional Magnetic Resonance Imaging in Brain Tumour Patients

Computer 47

S. Gevers1, J. N. van der Meer2, R. B. Willemse2, C. B.L.M. Majoie2, A. J. Nederveen2

1Academic Medical Centre , Amsterdam, Netherlands; 2Academic Medical Centre, Amsterdam, Netherlands

Functional magnetic resonance imaging (fMRI) based on the blood oxygenation level dependent (BOLD) signal, is used to assess the spatial relationship between eloquent cortical areas and brain tumour tissue. However, accumulating evidence suggests that the BOLD signal in the vicinity of tumour tissue does not reflect neuronal activity as accurately as it does in healthy brain tissue. Altered BOLD physiology might cause inverse responses to stimuli, that are missed by conventional GLM analysis. These false negative activations could undermine the applicability of fMRI in pre-neurosurgical brain mapping. In this study we quantified negative BOLD responses (NBR) in brain tumour patients using spectral analysis.

 

Innovative Neuroimaging Sequences & Applications I

Hall D                                   Wednesday 13:30-15:30                                                                                                                                       

13:30         3498.     Contrast Optimisation for SWI Venography at 7T

Computer 48

Markus Barth1,2, Peter J. Koopmans1

1Radboud University, Nijmegen, Netherlands; 2University Duisburg-Essen, Essen, Germany

We investigate the implications of a high magnetic field strength (7 Tesla) on MR venography based on susceptibility weighted imaging (SWI) and estimate the optimum echo time to obtain maximum contrast between blood and brain tissue. We therefore measure T2* relaxation times of gray matter, white matter, and venous blood in vivo that yield 32.9±2.3 ms, 27.7±4.3 ms, and 7.4±1.4 ms, respectively. Optimum TE was found to be 15 ms which is supported by theoretical considerations. Using this TE very high resolution 3D datasets were acquired that amazingly detailed depiction of intracortical veins of the human.

 

14:00         3499.     Removal of Air/tissue Interface Field Effects in Susceptibility Weighted Imaging

Computer 48

Jaladhar Neelavalli1, Yu Chung Norman Cheng2, Ewart Mark Haacke2,3

1Wayne State University, Detroit, Michigan, USA; 2Wayne State University, Detroit,, USA; 3The Magnetic Resonance Imaging Institute for Biomedical Research, Detroit, USA

We present here a novel method for removing the rapid phase variations due to background field inhomogenieties which are caused by large susceptibility differences at air/tissue interfaces. We test the efficiency of this method in a phantom and apply it to human SWI phase images. These images are used to produce significantly higher quality susceptibility weighted magnitude images in the midbrain and forebrain regions.

 

14:30         3500.     Optimisation of Double-Inversion Recovery Sequences at 7T

Computer 48

Jennifer Elizabeth Dixon1, Paul S. Morgan1, Matthew J. Brookes1, Emma C. Tallantyre1, Nikos Evangelou1, Peter G. Morris1

1The University of Nottingham, Nottingham, UK

DIR sequences have been found to be useful in the detection of cortical MS lesions. However, the low SNR available in these images at 3T suggests the importance of developing the sequence for use at higher field strengths. This requires the determination of inversion times to provide the desired contrast between grey matter and white matter, and must address the effects of the variation in flip angle due to B1 inhomogeneity at 7T. We present images acquired at both 3T and 7T for a range of TRs which successfully null the signal from WM and CSF.

 

15:00         3501.     Detection of White Matter Disease in the Brain and Spine Using Double Inversion Recovery SPACE at 3 Tesla

Computer 48

Agus Priatna1, Jaeseok Park2, Chin-I Chen3, Shoe Mar, Yvette Sheline3, Tammie L.S. Benzinger3

1Siemens Medical Solutions, St Louis, Missouri, USA; 2Siemens Medical Solutions, Erlangen, Germany; 3Washington University School of Medicine, St Louis, Missouri, USA

Double IR SPACE or TSE has been shown to be useful for detecting white matter diseases such as multiple sclerosis in adult brain at 1.5T. Unlike conventional technique of using conventional 2D T2-weighted Dark-Fluid imaging (FLAIR), the double IR SPACE sequence provides better contrast between the white matter and the lesion because of the suppressed white matter signal. Because of the white matter lesions can spread to the brain and the spine, it would be desired to develop method of detecting the lesions in both brain and spine in adults, and pediatrics especially. The purpose of this study is to develop a method of detecting white matter diseases in both brain and spine in both pediatrics and adults using an optimized isotropic double inversion recovery 3D SPACE sequence at 3 Tesla.

 

13:30         3502.     Unreliability of Cortical Volumetry in Regions Near the Skull Base on 3D T1-Weighted Imaging: Comparison Study with 3D Double Inversion-Recovery Imaging

Computer 49

Eunhye Yoo1, Dong-Hyun Kim2, Hae-Jeong Park1, Eung-Yeop Kim1

1Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea; 2Yonsei University, Seoul, Republic of Korea

3D T1-weighted imaging is based on GRE sequence. Therefore, susceptibility artifact due to air-bone interface may happen and consequently give rise to hyperintensity within the cortex, which may be a problem for accurate and reliable measurement of the cortical volume. This pitfall can be solved if imaging is obtained with FSE sequence such as 3D double inversion-recovery imaging (DIR). In this study, we demonstrated that one or more regions in the bilateral orbitofrontal, inferior temporal, and fusiform cortices showed susceptibility artifacts on 3D T1-weighted imaging, causing underestimation of cortical volume, but not on 3D DIR in the corresponding regions.

 

14:00         3503.     Triple-Layer Appearance of the Primary Motor Cortex on Thin-Section Double Inversion-Recovery Imaging: Validation Study by Using Intraoperative Cortical Mapping

Computer 49

Eunhye Yoo1, Dong-Hyun Kim2, Jong-Hee Chang1, Hae-Jeong Park1, Eung-Yeop Kim1

1Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea; 2Yonsei University, Seoul, Republic of Korea

Preoperative determination of the primary motor cortex (PMC) is crucial. For this purpose, many methods by using specific morphology of the cortices and sulcus have been suggested. However, no studies suggested the method using substructure of the PMC. It has been suggested that the PMC shows triple-layer appearance on thin-section 2D double inversion-recovery imaging (DIR) in all subjects more than 10 years of age. However, validation has not been performed. The triple-layer appearance on thin-section 2D DIR was validated as a new imaging marker of the PMC by using an intraoperative cortical mapping in this study.

 

14:30         3504.     High Resolution T2* and Phase Contrast of Human AD Brain Tissue at 9.4T: A Structural Comparison

Computer 49

Rob J.A. Nabuurs1, Julien R. Milles1, Sanneke van Rooden1, Jeroen van der Grond1, J H. Reiber1, Mark A. van Buchem1, Louise van der Weerd1

1Leiden University Medical Center, Leiden, Netherlands

To further explore possible susceptibility effects caused by amyloid-&#946; plaques, we have obtained T2*-weighted magnitude and phase images at high magnetic field and high resolution from ex vivo human AD brain tissue. Different hypo-intense regions in the magnitude data showed a large variation in the corresponding phase data, showing that at high magnetic fields, the signal phase provides additional information about microscopic variations in magnetic susceptibility.

 

15:00         3505.     Comparison of Retinotopic Maps with Cortical Areas Identified Using High Resolution,  T2*-Weighted Images Acquired at 7T

Computer 49

Rosa Maria Sanchez Panchuelo1, Denis Schluppeck1, Stuart Clare2, Holly Bridge2, Richard Bowtell1, Sue Francis1

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

Here we investigate the correspondence of functionally defined visual regions V1 and MT to areas displaying hypointense banding in cortical grey matter in high resolution T2*-weighted images acquired at 7 T. Retinotopic mapping based on a moving visual stimulus and 1.5 mm isotropic resolution fMRI was carried out on 4 subjects, who were subsequently imaged using a 3D gradient echo sequence providing 0.4 mm isotropic resolution. Significant overlap of areas displaying obvious banding in the T2*-weighted data, with the functionally defined V1 and MT areas was found by analysis of maps of the inflated cortex.

 

13:30         3506.     Comparison of Inversion Algorithms in MR Elastography of the Brain

Computer 50

Matthew Christopher Murphy1, Kevin J. Glaser1, Joel P. Felmlee1, Richard L. Ehman1

1Mayo Clinic College of Medicine, Rochester, Minnesota, USA

MR elastography (MRE) has the potential to detect mechanical changes in brain tissue that result from the progression of disease.  Optimization is required to apply MRE to the brain.  One important factor is comfort, which can be significantly improved by decreasing the acquisition time.  This work shows that the direct inversion (DI) algorithm is preferred to local frequency estimation since its solution converges with less than two-thirds as many slices.  Therefore by implementing DI, acquisition time of MRE in the brain can be reduced.

 

14:00         3507.     Comparison of MR Elastography of the Brain at 1.5 T and 3.0 T

Computer 50

Matthew Christopher Murphy1, Kevin J. Glaser1, Joel P. Felmlee1, Richard L. Ehman1

1Mayo Clinic College of Medicine, Rochester, Minnesota, USA

MR elastography (MRE) is potentially capable of detecting focal or diffuse changes in shear stiffness of the brain, which result from mechanical changes in the brain due to disease progression.  To develop MRE into a useful diagnostic tool for neurological disorders it must be optimized beginning with field strength.  Experiments were performed in phantom and human volunteers.  Phase and magnitude signal to noise ratios show that MRE data collected at 3.0 T is higher quality than data collected at 1.5 T.

 

14:30         3508.     Adaptive Centric View Ordering for Magnetization Prepared Gradient Echo Imaging

Computer 50

Ersin Bayram1, Charles R. Michelich1, Anthony T. Vu1, Reed F. Busse2

1GE Healthcare, Waukesha, Wisconsin, USA; 2GE Healthcare, Madison, Wisconsin, USA

Magnetization prepared gradient echo sequences are routinely used for T1 weighted isotropic brain imaging to enhance gray-white matter contrast.  Views are ordered such that a fixed number of phase-encodes in a single kx-ky or kx-kz plane are collected in a segmented centric or sequential fashion after an IR pulse is applied followed by an optional delay for magnetization recovery. A 1D trajectory through ky-kz space is limiting since only certain segment sizes are allowed based on the prescribed matrix size. This work improves the efficiency of magnetization prepared brain imaging by introducing an adaptive centric view ordering.  In addition to decoupling the train length from the matrix size, it also allows desirable time saving strategies such as k-space corner removal and 2D auto-calibrated acceleration with non-separable grid which are not possible with conventional view ordering, since the number of views from one kx-ky or kx-kz plane to the next varies.

 

15:00         3509.     Ultra-Fast T2-W. Single Shot TSE and Single Shot FLAIR MR Imaging Combining SENSE, Variable Refocusing Angle and Partial Fourier: Evaluation on Cooperative and Non-Cooperative MS Patients in Comparison to Standard TSE and FLAIR Imaging

Computer 50

Jürgen Gieseke1, Birgit Simon2, Reanate Blömer2, Hans H. Schild2

1Philips Medical Systems, Bonn, Germany; 2University, Bonn, Germany

Introduction: Single shot and high SENSE-factor enable scan time shortening of about factor 10 for T2-w. TSE and factor 5 for TSE-FLAIR [4].  Purpose of the study was to evaluate the fast T2w.technique concerning the diagnostic image quality of non-cooperative MS patients

Material and Methods: Investigations were done at 3T. The sequences are combined with SENSE, partial Fourier and Flpi angle sweep.

RESULTS Concerning the head motion of the non-cooperative patients a correct diagnosis were difficult, whereas in the fast images the lesions could be correct detected.

DISCUSSION This technique potentially enables diagnostic image quality in non-cooperative patients.

 

 

Innovative Neuroimaging Sequences & Applications II

Hall D                                   Thursday 13:30-15:30                                                                                                                                           

13:30         3510.     Efficient Multi-Slice Fast Spin Echo Imaging with Reduced Flip Angles at High Field

Computer 40

Robert Marc Lebel1, Alan H. Wilman1

1University of Alberta, Edmonton, Canada

Here we employ reduced and variable refocusing flip angles for efficient (no delay time for SAR reduction) multi-slice FSE imaging at 4.7T. We investigate the magnetization transfer effect as a function of refocusing flip angle and demonstrate 25% signal attenuation in white matter with 180° pulses, but less than 5% attenuation at 60°. We show reduced flip angles are equally applicable to very rapid and to very high resolution imaging. We present HASTE images acquired in 600 ms/slice with 109 echoes at 55°, and very high resolution images (0.4 x 0.4 x 1 mm3) acquired in 6:30 with 100° pulses.

 

14:00         3511.     Non-Contrast Bulk Flow Imaging of Cerebrospinal Fluid (CSF) Using Time-Spatial Labeling Inversion Pulse (Time-SLIP)

Computer 40

Shinya Yamada1, Mitsue Miyazaki2,3, Minako Higashi4, Hitoshi Kanazawa3, Yukuo Morohoshi, Stefan Bluml5, Gordon J. McComb

1Tokai University at Oiso, Oiso, Japan; 2Toshiba Medical Research Institute USA, Vernon Hills, USA; 3Toshiba Medical Systems Corp., Otawara, Japan; 4Toshiba Medical Systems, Yokohama, Japan; 5Children

To observe bulk CSF flow, time-spatial labeling inversion pulse (time-SLIP) is applied to observe the CSF flow in a range of 1500 to 6000 ms. This technique was applied in various regions, including the aqueduct of the Sylvius, foramen of Monro, prepontine cistern and in the spinal canal. The bulk CSF flow was observed from the third to the fourth ventricle through the aqueduct. Up and down bulk CSF motions are seen in the ventral side of the subarachnoid space. In addition, CSF reflux was observed from the third ventricle to the lateral ventricle in all normal volunteers.

 

14:30         3512.     Rapid CSF Measurement Without Operator Intervention Using BSSFP 3D Radial Acquistion

Computer 40

Youngkyoo Jung1, Alexey A. Samsonov1, Walter F. Block1

1University of Wisconsin-Madison, Madison, Wisconsin, USA

Typical measurements of CSF are using SPGR scans or multiple acquisitions with different T1 and T2 weightings. Those methods are complicated by post-processing schemes requiring registration or segmentation. We propose a rapid, 90 sec scan for measuring CSF volume without operator intervention using a single inversion recovery (IR) balanced SSFP (bSSFP) scan with a 3D PR acquisition. A single 3D isotropic acquisition may provide higher precision, bright CSF, faster scan times, and simplified processing relative to conventional SPGR acquisition methods.

 

15:00         3513.     Temporal Course of Hyperdynamic Pulsatility and Ventricular Dilation in a New Rat Model of Communicating Hydrocephalus

Computer 40

Shams Rashid1, Helene Benveniste,12, Michael R. Egnor1, Jie Li3, James P. McAllister4, Mei Yu2, Mark E. Wagshul1

1Stony Brook University, Stony Brook, New York, USA; 2Brookhaven National Laboratory, Upton, New York, USA; 3Wayne State University, Detroit, Michigan, USA; 4University of Utah, Salt Lake City, Utah, USA

Hydrocephalus has long been thought to be caused by CSF flow obstruction or malabsorption, but this fails to explain many observations about communicating hydrocephalus (CH).  In a new rat model of CH, changes in ventricular volume (VV) and CSF stroke volume (SV) in the cerebral aqueduct were investigated using MRI. Hydrocephalus developed in two very distinct forms: severe - highly elevated SV and VV, and mild - mild ventricular dilation and slightly elevated SV which dropped back to normal levels after one week. These results may have important clinical implications for understanding the significance of elevated CSF pulsations in CH.

 

13:30         3514.     Evaluation of T1-Weighted MRI Methods for Clinical Brain Imaging at 3.0 Tesla

Computer 41

Chen Lin1, Andrew Kalnin1, Kristine Mosier1, Annette Johnson2, Larry Friggle3, Aaron Flammang4

1Indiana University School of Medicine, Indianapolis, Indiana, USA; 2Wake Forest University School of Medicine, Winston Salem, North Carolina, USA; 3Clarian Health Partners, Indianapolis, Indiana, USA; 4Siemens

Direct comparison of imaging quality of five T1 weighted imaging methods, conventional SE with reduced flip angle, T1 FLAIR, 2D and 3D FLASH and MP-RAGE at 3.0T was made by scanning a group of healthy adult volunteers. Based on quantitative measurement of SNR and CNR of gray matter and white matter as well as independent review by radiologists, T1 FLAIR was shown to provide the best overall image quality. Other advantages and drawbacks of each method were also analyzed.

 

14:00         3515.     Improvement of Midbrain Nuclei Susceptibility Contrast in T1-Weighted SPGR for Image Guided Deep Brain Stimulation

Computer 41

Nan-kuei Chen1, Geoffrey S. Young2

1Duke University, Durham, North Carolina, USA; 2Brigham and Women's Hospital, Boston, Massachusetts, USA

3D-SPGR currently used for stereotactic image guidance in deep-brain stimulation does not provide adequate midbrain nuclei contrast. Therefore an extra T2-weighted MRI is needed for midbrain nuclei visualization. However, the surgical planning based on two datasets may be susceptible to further errors related to subject movement. Here we propose a procedure capable of providing both stereotactic T1-MRI and high midbrain nuclei contrast without extra scans. Acquisition parameters of SPGR are chosen in a way that (1) T1 contrast suitable for stereotactic imaging is obtained, and (2) high midbrain nuclei contrast is achieved by performing regional susceptibility weighted reconstruction.

  

14:30         3516.     Investigating the Function of the Cardiovascular and Respiratory Centers in the Brain Stem by Breath-Holding Using Reduced FOV EPI Technique

Computer 41

Chun-Jung Juan1, Tzu-Cheng Chao2, Yi-Jui Liu3, Cheng-Yu Chen1, Chun-Jen Hsueh1, Chung-Ping Lo1, Hsiao-Wen Chung2, Te-Cheng Lai3, Guo-Shu Huang1

1Tri-Service General Hospital, Taipei, Taiwan; 2National Taiwan University, Taipei, Taiwan; 3Feng Chia University, Taichung, Taiwan

In skull base, the susceptibility of regional magnetic field inhomogeneity distorts the EPI images due to long readout train. We use zoom EPI technique to reduce the FOV in the phase-encoding direction to remedy the imaging distortion on EPI sequence. Then, the function of the cardiovascular and respiratory function, which are located in the lower pons, is investigated by breath-holding fMRI. Our results will show you satisfactory imaging quality of hte brain stem and activation in the lower pons in the breath-holding task.

 

15:00         3517.     Constructive Interference Steady-State Imaging in Post-Mortem Human Brain: An Alternative or Adjunct to Conventional Autopsy?

Computer 41

Jennifer Andrea McNab1, Ned Jenkinson2, Tipu Aziz2, Karla L. Miller1

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

Post-mortem diagnosis of neuropathology is an important means of learning more about diseases of the central nervous system and can have a major impact on the management of future patients. Though several studies have previously presented post-mortem MRI, most have not been optimised for the changed properties of fixed tissue. Due to similar relaxation times in WM and GM conventional T1, T8 -weighted imaging protocols no longer provide adequate contrast in fixed tissue. In this study, we present  a 3D steady-state imaging protocol, which provides excellent contrast in fixed tissue.

 

13:30         3518.     Optimization of MDEFT with FLASH-EPI Hybrid Readout for Optimum Contrast in Selected Brain Areas [Not Available]

Computer 42

Steffen Volz1, Ralf Deichmann1

1Brain Imaging Center, J.W. Goethe University, Frankfurt, Germany

In fMRI the MDEFT sequence is widely used as T1-weighted reference scan with high spatial resolution because of its advantageous contrast characteristics, especially at high field strengths. An MDEFT sequence with FLASH-EPI hybrid readout and a total acquisition time of 6 min was optimized at 3T to achieve maximum CNR and SNR for cortical WM and GM and to enhance the visibility of brain structures in the basal ganglia. The SNR and CNR values achieved were similar to results reported for a standard version of MDEFT with the same spatial resolution but twice the acquisition time.

 

14:00         3519.     Routine High Resolution MRI in Small Animals at 9.4 Tesla Using a Cryogenic Quadrature Transceive RF Probe

Computer 42

Christof Baltes1, Nicole I. Radzwill2, Simone C. Bosshard1, Daniel Marek3, Markus Rudin1,4

1University and ETH Zurich, Zurich, Switzerland; 2Bruker BioSpin MRI, Ettlingen, Germany; 3Bruker BioSpin AG, Fällanden, Switzerland; 4University Zurich, Zurich, Switzerland

Recently, the benefits of cryogenic RF probes for small animal MR imaging have been investigated in detail. Cooling of the RF coil and the connected preamplifier resulted in significantly increased sensitivity. The aim of this work was a comparison under in vivo conditions of a cryogenic quadrature transceive coil to a room temperature quadrature receive only coil. The comparison revealed SNR gains of 2.5 on average for both spin echo and gradient echo sequences. In addition, this flexible and robust cryogenic RF probe allowed for in vivo micro-imaging of the cerebellum in reasonable scan times.

 

14:30         3520.     Sleepiness and Accuracy Correlate Abnormal BOLD-FMRI Responses During Sleep Deprivation

Computer 42

Dardo Tomasi1, Ruiliang Wang1, Frank Telang1, Vasilios Boronikolas1, Millard C. Jayne1, Gene-Jack Wang1, Joanna S. Fowler1, Nora D. Volkow2

1Brookhaven National Laboratory, Upton, USA; 2National Institutes of Health, Bethesda, USA

Here we investigate the effect of sleep deprivation (SD) on brain activation using a set of visual attention and working memory tasks with graded levels of difficulty and high-field fMRI. During the SD session, 16 healthy men had higher sleepiness, lower performance accuracy, higher thalamic activation, lower prefrontal activation, lower deactivation in the precuneus, and lower connectivity between the thalamus and the precuneus than during the rested wakefulness session. For both tasks, activation of the anterior cingulate correlated with sleepiness and accuracy. These findings suggest that under SD, accurate performance require larger recruitment of brain resources involved with alertness.

 

15:00         3521.     Plasticity in Congenitally Blind During Object Recognition

Computer 42

Anand Mohan Sinha1, Senthil S. Kumaran1, Rohit Saxena1

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

The study investigates the neuronal centers associated with perception of object in congenitally blind using fMRI. We recruited thirty right handed congenitally blind subjects and 22 healthy controls. Significant bilateral parietal activation was observed in controls as observed using one-way ANOVA test (p< 0.001). The perception in congenitally blind subjects involves cingulate and temporal areas as compared to middle occipital gyrus in controls, suggesting brain reorganization associated with tactile object recognition (visual imagery) task.

 

13:30         3522.     MRI Texture Analysis as a Non Invasive Tool to Show Cerebral Structural Changes After Herbicide Ingestion in Mice

Computer 43

Sandra Même1, William Même, Bich Thuy Doan1, Jean-Claude Beloeil1

1CNRS CBM UPR4301, Orléans, France

Glufosinate ammonium (or phosphinothricin PPT) is the active element of herbicides widely used in agriculture or truck farming . Lots of transgenic plants resistant to that herbicide have been developed. Significant quantities of PPT are present in plants and consequently, in animal or human food which can lead to chronical intoxication. PPT also interacts with the cerebral glutamatergic system in mammalians and can, even with low dose, lead to neurological disorders. The aim of this study was to use Magnetic Resonance Imaging (MRI) coupled with Texture Analysis as a non invasive tool to evaluate the effect of PPT treatment with different doses on mice central nervous system.

 

14:00         3523.     Detection of Radiation-Induced Brain Injuries by Multi-Modal Magnetic Resonance Imaging

Computer 43

Kevin C. Chan1,2, Matthew M. Cheung1, Ke Xia Cai1, Ho-fai Lau1, C N. Tam1, Si Lun Wang1, Pek Lan Khong1, Ed Xuekui Wu1

1The University of Hong Kong, Pokfulam, Hong Kong

This study aimed to employ in vivo multi-modal MR imaging to understand the radiation-induced brain damage in rats in correlation to histopathological changes at 12 months after radiation treatment. Results showed a loss in contrast in the ipsilateral corpus callosum and external capsule in T2WI, with a corresponding hyperintensity in trace map. The fractional anisotropy has also dropped in the fimbria of the hippocampus, suggestive of degeneration in this white matter structure; Significant increase in Cho:Cr and Lac:Cr ratios, and a marginally significant elevation in Glu:Cr ratio were observed at the site of radiation, whereas colocalization was found between manganese-enhanced MRI pattern and immunostaining for GFAP, MnSOD and GS, likely due to their Mn-dependent upregulation against oxidative stress and glutamate excitotoxicity.

 

Alzheimer's Disease, Dementia, Age

Hall D                                   Thursday 13:30-15:30                                                                                                                                           

14:30         3524.     Comparative Diagnostic Utility of the Different MR Modalities in Mild Cognitive Impairment and Its Use as Predictor of Dementia

Computer 43

Nicolas Fayed1, Jorge Humberto Davila Acosta1, Antonio Oliveros1

1Hospital Quiron, Zaragoza, Spain

The objective was to evaluate the use of PWI, DWI and MRS in patients with amnesic mild cognitive impairment as predictor´s tools of conversion to Dementia.  Also, we tried to differentiate the different types of aMCI using these tools. The percentage of people who converted to dementia was 45%, including not only patients with Alzheimer Disease but also mixed dementia, vascular dementia and Lewy Body Disease. MRS results showed the best area under ROC curve to predict the conversion from aMCI to Dementia, being the best predictor the ratio NAA/Cr in the Posterior cingulated gyri.

 

15:00         3525.     Regional Assessment of White Matter Damage at Different Stages of Alzheimer's Disease Using TBSS

Computer 43

Laura Serra1, Mara Cercignani1, Delia Lenzi1,2, Roberta Perri1, Fabrizio Fasano1,3, Carlo Caltagirone1,4, Emiliano Macaluso1, Marco Bozzali1

1IRCCS Fondazione S. Lucia, Roma, Italy; 2Sapienza Università di Roma, Roma, Italy; 3Siemens Medical, Italy; 4Università di Roma Tor Vergata, Roma, Italy

It is known that Alzheimer's disease (AD) involves both white and grey matter, and that abnormalities of both tissues correlate with measures of cognitive decline. This study aims at localizing white matter abnormalities in patients with mild cognitive impairment (MCI) using tract based spatial statistics (TBSS), a novel approach to perform whole-brain analysis of diffusion tensor (DT) MRI. We found widespread white matter abnormalities in patients with AD compared to both MCI patients and healthy subjects. The areas of abnormalities in patients with MCI compared to healthy controls were less, and of lesser extent.

 

13:30         3526.     Voxel Based Relaxometry of Alzheimer's Disease

Computer 44

Himachandra Chebrolu1, Charles Dennis Smith1, Peter Andrew Hardy1

1University of Kentucky, Lexington, USA

Voxel Based Relaxometry was used to correlate changes in T2 with cognitive status in a group of normal, MCI and AD subjects. Results show regions of negatiave correlation between T2 and MMSE in the temporal lobe and the hippocampus consistent with the known course of atrophy in AD.

 

14:00         3527.     Significantly Asymmetric Patterns of Periventricular Atrophy in Alzheimer Disease, Mild Cognitive Impairment, and Memory Complainers Detected on Clinical MR Images

Computer 44

Lucs Ferrarini1, Walter Miguel Palm1, Hans Olofsen1, Jeroen van der Grond1, Mark A. van Buchem1, Johan H.C. Reiber1, Faiza Admiraal-Behloul1

1Leiden University Medical Center, Leiden, Netherlands

The aim of this work was to investigate left-right asymmetries in the patterns of periventricular atrophy in patients with Alzheimer Disease (AD), Mild Cognitive Impairment (MCI), and memory complaints (MC), in clinical MR images. The study included 63 AD, 28 MCI, 21 MC, and 28 healthy volunteers. A robust shape analysis technique was used to highlight local ventricular shape changes and estimate both the extent and severity of periventricular atrophy. Results were clustered in symmetrical regions and compared with the Kolmogorov-Smirnov test. The analysis showed how MC and MCI affect mostly right periventricular structures, and AD mostly left periventricular structures.

 

14:30         3528.     Metabolite Profiles in the Frontal and Occipital Cortices in Alzheimer’s Disease as Analyzed by HRMAS 1H NMR

Computer 44

Liya Wang1, Marla Gearing1, Xiaoxia Wang1, Shaoxiong Wu1, Carolyn C. Meltzer1, Hui Mao2

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

Synopsis               Neurochemical changes in the frontal and occipital cortices of AD and age matched non-demented controls were analyzed using HRMAS 1H NMR and intact postmortem tissue.  Metabolite profiles obtained from those regions revealed statistically significant decreases of NAA, GABA, Cho, MI, aspartic (Asp) and taurine (Tau) as well as increases of phosphocholine (PC) and glyocerphosphocholine (GPC) in the AD brains. A resonance at 3.71 and 5.85 ppm, not reported previously, appeared in 75% AD samples and 91% specificity respectively.  Furthermore, the abnormal metabolite profiles of AD brain were strongly correlated with the APOE genotypes of the subjects.

 

15:00         3529.     Diffusion Tensor Imaging and Cortical Thickness Mapping of Mild Cognitive Impairment

Computer 44

Liya Wang1,2, Felicia C. Goldstein1, Chunchun Ni1, Mingguo Qiu3, James J. Lah1, Allan I. Levey1, Hui Mao4

1Emory University School of Medicine, Atlanta, Georgia, USA; 2The Second Hospital of Shenzhen, Shenzhen, People's Republic of China; 3Third Military Medical University, Chongqing, People's Republic of China; 4Em

The study examined the utility of DTI and cortical thickness mapping in identifying patients with mild cognitive impairment (MCI).  Fractional anisotropy (FA), apparent diffusion coefficient (ADC) and cortical thickness in the left temporal WM and GM were significantly different in MCI patients versus normal aging controls. The combination of FA and cortical thickness measurements in temporal areas improved the accuracy of differentiating MCI patients from healthy controls compared to either measure alone.

 

13:30         3530.     Reduced Glutamate in the Hippocampus in Mild Cognitive Impairment and Alzheimer Disease

Computer 45

Raul Rajiv Rupsingh1,2, Michael Borrie2,3, Matthew Smith3, Jennie Wells2,3, Rob Bartha1,2

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

LASER localized MRS data were acquired from the right hippocampus of 10 Normal Elderly Controls, 6 subjects with Mild Cognitive Impairment and 6 patients with Alzheimer Disease at baseline and at 1-year. No significant differences in the rate of metabolite change were found between groups. Cross-sectional analysis revealed significant differences in the levels of NAA and glutamate between groups at both time points.

 

14:00         3531.     Assessment of Cerebral Blood Flow in Alzheimer's Disease by Continuous Arterial Spin Labeling MR Imaging

Computer 45

Rui Wang1, Saying Li1, Xuna Zhao2, Min Chen1

1Beijing Hospital, Beijing, People's Republic of China; 2Philips medical system, Beijing, People's Republic of China

The continuous arterial spin labeling (CASL) MR imaging is another method to detect CBF abnormalities. Our aim is to compare regional CBF values between AD patients and control subjects to explore the clinical utility of CASL. Eighteen AD patients and 15 control subjects underwent 3.0 T CASL and structural MRI. The CBF values of bilateral frontal, temporal, temporoparietal, parietal cortices and hippocampal areas were significantly decreased relative to control subjects(P<0.05). CASL can show regional hypoperfusion with AD, in cerebral regions involved similar to that seen with SPECT. The results suggest CASL is a useful tool for CBF characterization of AD.

 

14:30         3532.     Regional Demyelination of Subcortical White Matter in Early Alzheimer’S Disease: A Magnetization Transfer Imaging Study

Computer 45

Eleonora Fornari1, Maria G. Knyazeva1, Philippe Maeder1, Joseph Ghika1, Andrea Brioschi1, Isebelle Bourquin1, Reto Meuli1

1Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland

Alzheimer’s disease is a neurodegenerative disorder manifested by progressive cognitive deterioration. Since higher cognitive functions are based on distributed neural networks, the AD-associated cognitive impairment is expected to result from the compromised cortical connectivity. The aim of this study is to assess the regional state of myelination of the subcortical white matter in the newly diagnosed AD patients.

Our results point to a diffused degenerative process affecting the subcortical WM early in AD. Regional mapping of myelin loss in AD patients is an accurate tool providing anatomical information that can explain clinical manifestations of the disease, and its early pathogenesis.

  

15:00         3533.     T1ρ MRI as a Clinical Biomarker of Alzheimer's Disease

Computer 45

Matthew A. Sochor1,2, Christopher Davatzikos, Elias R. Melhem1, Christopher M. Clark, Ravi Reddy1, Ari Borthakur1

1University of Pennsylvania, Philadelphia, Pennsylvania, USA

Earlier diagnosis of Alzheimer’s Disease (AD) is essential to the development of drugs and treatments to halt or reverse the disease’s progression. In an ongoing clinical study, T1rho values are measured in the temporal lobe (TL) of AD and mildly cognitively impaired (MCI) patients, and age-matched controls.  T1rho values are automatically reported after segmentation of gray and white matter in the TL.  We found an increase of 5% (p<0.05) in gray matter and 8% (p<0.01) in white matter T1rho in AD patients over controls. The MCI cohort’s average T1rho values were between the AD and control cohorts.

 

13:30         3534.     Resting State FMRI of the Early Stages of Alzheimer's Disease [Not Available]

Computer 46

Tommaso Gili1,2, Laura Serra3, Federico Giove1,2, Delia Lenzi2,3, Emiliano Macaluso3, Carlo Caltagirone3,4, Bruno Maraviglia,12, Marco Bozzali3

1Enrico Fermi Center, Rome, Italy; 2Sapienza University, Rome, Italy; 3IRCCS Santa Lucia Foundation, Rome, Italy; 4Tor Vergata University, Rome, Italy

The synchrony of low-frequency fluctuations in resting stat  fMRI time series implies that there is underlying functional organization of the brain. In the present work, we compare low frequency correlation analysis obtained from patients with amnestic Mild Cognitive Impairment and patients with Alzheimer’s Disease (AD) to that obtained from an age-matched group of healthy subjects. Our study suggests that a pattern of abnormalities, similar  to the one previously obtained from AD patients, is already present in patients with MCI, thus characterising the cognitive dysfunction occurring in AD pathology since its early stages.

 

14:00         3535.     High Field Amyloid Imaging

Computer 46

Sanneke van Rooden1, Mathias van Osch2, Wouter Teeuwisse2, Rob Nabuurs2, Louise van der Weerd2, Mark van Buchem2, Jeroen van der Grond2

1Radiology LUMC, Leiden, Netherlands; 2Radiology LUMC, Netherlands

Alzheimer's Disease (AD) is characterized neuropathologically by extracellular amyloid plaques. The specific aim of the study was to find optimal acquisition parameters to visualize ex vivo the amyloid burden and small microbleeds in deceased HCHWA-D patients at whole body 7T.  The advantage of the HCHWA-D model is that all mutation carriers have a severe vascular amyloid burden. Gradient echo brain imaging at high field strengths offers excellent possibilities to visualize small distortions of the magnetic field, offering the potential to detect amyloid plaques. A multi-echo approach may be useful to differentiate between distortions caused by air bubbles and iron accumulation

 

14:30         3536.     Relation of Corpus Callosum Commissural System Volume and Its Projection Regions to Volume of White Matter Lesion Load and Whole Brain Atrophy with Age in Healthy Adults

Computer 46

Svetlana Egorova1, M P. Sampat1, C Sander1, Deborah Blacker2, M S. Albert2, R J. Killiany3, C R. Guttmann1

1BWH, HMS, Boston, Massachusetts, USA; 2MGH, HMS, Boston, Massachusetts, USA; 3BU, Boston, Massachusetts, USA

We analyze the degree of age-related atrophy changes of the corpus callosum during normal aging in healthy subjects and its relationship with white matter lesion load and whole brain atrophy.

 

15:00         3537.     Differential Effects of Age and Hypertension on Brain Anatomy and Physiology Assessed by Regional T2* Relaxometry and Volumetry

Computer 46

Karen M. Rodrigue1, E. Mark Haacke1, Naftali Raz1

1Wayne State University, Detroit, Michigan, USA

Within a healthy aging model, regional T2* values decline with age in the prefrontal cortex, medial temporal structures and striatum, but not in the primary visual cortex. Those differences are enhanced by hypertension.  In the hippocampus and the entorhinal cortex, the effect of age on T2* is stronger than on the respective volumes.

 

13:30         3538.     Anterior-To-Posterior Hippocampal Metabolic Heterogeneity in Healthy Elderly and Young Adults Using 3D 1H MR Spectroscopy

Computer 47

Kevin King1, Songtao Liu1, Lidia Glodzik-Sobanska1, James Babb1, Mony de Leon1, Oded Gonen1

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

To quantify the metabolite concentrations along the anterior-posterior axis of the hippocampus in healthy young and elderly, 6 ¡®young¡¯ and 6 ¡®elderly¡¯ volunteers underwent 3D 1H-MRSI at 3T with (0.5 cm)3 spatial resolution. Absolute concentrations of NAA, Cho and Cr were obtained in each voxel. A significant metabolic heterogeneity is observed between young and old and along the anterior-posterior axis of the hippocampus in both age groups. These underscore the importance of age-matching and that consistent voxel placement is important for correct comparisons of both absolute metabolic levels and metabolite ratios in (a) longitudinal intra-subject; and (b) inter-subject cross-sectional studies.

 

14:00         3539.     Cortical Thickness Measurements with Buried Sulcus Recovery from MRI: An Application to Dementia

Computer 47

Sandhitsu R. Das1, Brian B. Avants1, Murray Grossman1, James C. Gee1

1University of Pennsylvania, Philadelphia, Pennsylvania, USA

A new methodology for cortical thickness measurements from MR images is presented. The method uses registration-based techniques to define correspondence  between white matter and gray matter surface points and the distance between corresponding points is defined as thickness. Using diffeomorphic mapping allows for resolution of deep sulci often mislabeled as gray matter. The method is applied to a longitudinal study of thickness change in frontotemporal dementia.

 

14:30         3540.     Cerebral Vasoreactivity as the Main Determinant of Progression of White Matter Hyperintensities in Small Vessel Disease: CADASIL as a Monogenetic Model

Computer 47

Michael K. Liem1, Saskia A.J. Lesnik Oberstein1, Joost Haan,12, Rivka van den Boom1, Michel D. Ferrari1, Mark A. van Buchem1, Jeroen van der Grond1

1Leiden University Medical Center, Leiden, Netherlands; 2Rijnland Hospital, Leiderdorp, Netherlands

In this study we investigated the role of basal total cerebral blood flow (TCBF) and cerebral vasoreactivity (CVR) on progression of characteristic MRI abnormalities in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), which is a monogenetic model of arterial small vessel disease. We found that low CVR is associated with faster progression of white matter hyperintensities, but not with progression of lacunar infarcts or microbleeds. TCBF was not associated with progression of MRI abnormalities. CVR is an important causal factor in development of white matter hyperintensities in CADASIL and possibly also in small vessel disease in general.

 

15:00         3541.     Periventricular Apparent Diffusion Coefficient, Cerebrospinal Fluid (CSF) Aqueductal Flow Rate and Evan’s Index - Value of Pre and Post Shunt Comparison in Idiopathic Normal Pressure Hydrocephalus (NPH)

Computer 47

Samuel ES Ng1, Angela MS Low1, Kok Kee Tang2, Robert K. Kwok1

1Mount Elizabeth Hospital, Singapore, Singapore; 2KK Tang Adult & Pediatric Neurosurgery, Singapore

We believe that the symptoms of NPH are caused not by ventriculomegaly, but by a blockage to the flow of extracellular cerebral fluid.  

If the former were true, shunt responders would show interval decrease in FR / EI.   If the latter were true, responders would post an interval decrease in ADC, vice versa for non-responders.

In our study, for responders, improvement in MRI readings for ADC, FR and EI was seen in 100%, 67% and 100%. For the non-responders, similar readings ADC, FR and EI were seen in 0%, 67%, and 67%.

Only the ADC showed total concordance with shunt response.

 

 

13:30         3542.     Measurement Of Transependymal Bulk CSF Flow in Communicating Hydrocephalus [Not Available]

Computer 48

Noam Alperin1, Sang H. Lee2, William Chiang1, Roberta Glick3, Tadanori Tomita4, John Curran4

1University of Illinois, Chicago, Illinois, USA; 2University of Illinois         , Chicago, Illinois, USA; 3Rush University, Chicago, Illinois, USA; 4Children's Memorial Hospital, Chicago, Illinois, USA

Periventricular hyper intensities is often seen in hydrocephalous and is associated with edema or CSF retention. The origin for this increased interstitial water content could be local, either vascular or cellular, or ventricular by transependymal bulk CSF flow. Identifying the possible origin for these hyper intensities may help establish the correct diagnosis and treatment. We tested the hypothesis that ventricular-to-parenchyma transependymal flow is associated with reversed net CSF flow through the aqueductal by measurements of bulk aqueductal CSF flow in hydrocephalic patients and in two control groups in whom no hyperintensities were present.  Revered balk flow was found only in the hydrocephalic group. All patients with negative net balk flow demonstrated white matter periventricular hyperintensities.

 

14:00         3543.     Voxelwise DTI and FLAIR Correlation Analysis for Characterization of White Matter Degeneration

Computer 48

Wang Zhan1, Yu Zhang1, Susanne Mueller1, Peter Lorenzen1, Efstathios Hadjidemetriou1, Xiaoping Zhu1, Shannon Buckley1, Marzieh Nezamzadeh1, Norbert Schuff1, Michael W. Weiner1

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

White matter (WM) degeneration has been investigated with two major MRI modalities: i.e. diffusion tensor imaging (DTI) to detect the alterations of microstructural integrity in WM, and fluid attenuated inversion recovery (FLAIR) to exam the macroscopic WM lesions (WML). However, the specific relationship between them remains largely unknown in characterizing lesion severity. The present study aims to clarify this relationship by using voxelwise correlation analysis between DTI and FLAIR images acquired from a same group at 4T. Results from both in-vivo and simulations suggest that combined DTI and FLAIR modalities together may provide higher specificity in characterizing the WM degeneration than each alone.

 

14:30         3544.     Detecting Diffuse White Matter Alterations in Healthy Volunteers Using Tissue Specific Imaging: Potential Implications for Cognitive Function

Computer 48

Vasiliki N. Ikonomidou1, Susan K. Stern1, Antonio Gallo1, Iordanis E. Evangelou1, Joan M. Ohayon1, Mary Ehrmantraut1, Irene Cortese1, Constantinos D. Frantzis1, Henry F. McFarland1, Robert L. Kane2, Francesca Bagnato1

1National Institutes of Health, Bethesda, USA; 2VA Medical Center, Baltimore, USA

Diffuse white matter changes are a common finding in clinically healthy subjects. No clinical significance has been attributed to them. In this study, we present a semi-automated method to identify and quantify affected white matter tissue using Tissue Specific Imaging. Results from 21 healthy volunteers indicate that the affected volume fraction has significant correlations with the subjects’ scores in some components of a comprehensive cognitive battery for multiple domain evaluation.

 

15:00         3545.     Radial Diffusivity Measurement  of the Corpus Callosum to Investigate Normal Aging and Pathological Cognitive Decline

Computer 48

Fabrizio Fasano1,2, Mara Cercignani1, Barbara Basile1,3, Laura Serra1, Delia Lenzi1,4, Carlo Caltagirone1,5, Marco Bozzali1

1Fondazione Santa Lucia, Roma, Italy; 2Siemens Medical, Milano, Italy; 3Scuola di Psicoterapia Cognitiva (SPC), Roma, Italy; 4Università La Sapienza, Roma, Italy; 5Università Tor Vergata, Roma, Italy

An high sensitivity radial diffusivity estimation is performed in the corpus callosum of 19 young and 6 ederly healthy volunteers, and on 6 mild cognitive impairment  and 4 alzheimer disease patients  Our results show a correlation between radial diffusivity values in the genu of corpus callosum and normal aging. In the same region also a promising trend of the mean radial diffusivity is found among groups.

 

Psychiatric MRI/MRS

Hall D                                   Thursday 13:30-15:30                                                                                                                                           

13:30         3546.     Magnetization Transfer Imaging and Volume Changes Detected by MRI in First-Episode Schizophrenia

Computer 49

Gary Price1, Mara Cercignani1, Elvina M. Chu1, Thomas R E Barnes2, Gareth J. Barker3, Eileen M. Joyce1, Maria A. Ron1

1University College London, London, UK; 2Imperial College Faculty of Medicine, London, UK; 3King’s College London, London, UK

This study uses 3D IR-SPGR and 3D MT-SPGR sequences to study 48 patients with 'first-episode' schizophrenia and 47 controls.  Two volumes from the MT-SPGR sequence were co-registered using FLIRT and MTR maps were then calculated on a pixel-by-pixel basis.  SPM2 was then employed integrating the "optimised VBM" approach.  MTR reductions were seen in the patient group but not controls.  Grey and white matter loss was also seen in the patient group, as well as grey matter increases in the patient group in the superior frontal gyral region.  The results suggest that MTR and volume abnormalities detected in patients may reflect different underlying processes or different stages of a process in the illness.

 

14:00         3547.     ROI-Based VBM Study of Amygdala and Hippocampus in First-Episode Treatment Naive Schizophrenia Patients

Computer 49

Ling Zou1, Luo Ouyang2, Wei Deng3, Qin Chen3, Zhengyang Li1, Weiwei Zhang1, Su Lv1, Yi Wei1, Tijiang Zhang1, Xiaoqi Huang1, Dongming Li4, Xiuli Li4, Tao Li3, QiYong Gong1

1West China Hospital, Sichuan Universty, Chengdu, People's Republic of China; 2South West University, People's Republic of China; 3West China Hospital, Sichuan Universty, People's Republic of China; 4West China

Small medial temporal lobe volumes have been reported as one of the common findings in schizophrenia patients, some of them with inconsistent substructure changes. However, most studies recruited chronic patients regardless of medication. We applied ROI based VBM study of gray matter density in amygdala and hippocampus to patients only with first-episode, antipsychotic-naive schizophrenia, and consequently observed no significant changes. It is likely that the observed structural abnormalities of amygdale and hippocampus in previous studies may attribute to medication and/or subsequent neurodegenerative changes over time. Future large cohort study is necessary to gain further insight into our current findings.

 

14:30         3548.     A Seven Year Longitudinal 31P MRS Study of Schizophrenia

Computer 49

Jodi E. Miller1,2, Peter C. Williamson2, Ravi S. Menon2,3, R W J Neufeld2, Dick J. Drost1,2

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

Our continuing longitudinal study of schizophrenia has measured phosphorus brain metabolism in patients and controls for a third time, seven years after the onset of disease using 3 dimensional chemical shift imaging.  This acquisition has allowed us to observe the effect of length of illness on metabolite changes in patients.  In the anterior cingulate there was a significant decrease in breakdown and synthesis products in patients as compared to controls.  In the left thalamus there was a trend of decreased breakdown products in patients as compared to controls.  Breakdown products in both of these regions were negatively correlated with length of illness.

 

15:00         3549.     2-D 1H MRSI Study of Prefrontal Cortex in the Brain of First-Episode Psychosis Patients

Computer 49

Jing-Huei Lee1,2, Wen-Jang Chu1, Mi Jung Kim1, Caleb M. Adler1, Stephen M. Strakowski1

1University of Cincinnati, Cincinnati, USA

The specific abnormalities of neurochemistry underlying the development of psychotic disorders (schizophrenic, schizoaffective, and bipolar disorder) are still not completely known. Some neuroimaging studies had reported that neuroanatomical changes in certain brain regions had been linked to these psychotic disorders. These aberrant changes are observed most prominently in medial temporal and prefrontal lobe regions. In this work, we extended the neuroimaging findings to the study of neurospectroscopy using 2D 1H MRSI with a focus on the prefrontal lobe region. Our findings suggest elevated choline levels in the prefrontal region may be associated with the severity of psychotic symptoms.

 

13:30         3550.     The Subdivided Corpus Callosum in Schizophrenia: A DTI Study

Computer 50

Pin-Yi Chiang1, Kun-Hsien Chou2, Yi-Ping Chao3, I-Yun Chen4, Tung-Ping Su5, Ching-Po Lin1,4

1Institute of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan; 2Institute of Biomedical Engineering, National Yang Ming University, Taipei, Taiwan; 3Institute of Electrical Engin

Numbers of studies have suggested that schizophrenia is a condition of abnormal connectivity in the cortico-cortical connections and the connections between the hemispheres. To understand the abnormal areas and the related connections, 25 schizophrenia patients and 25 healthy subjects were acquired and compared using DTI technique.  Comparing regional differences of fraction anisotropy (FA) between the patient-control groups can reflect the abnormal connectivity between the hemispheres in the specific cortical regions. The corpus callosum for analyzing was defined on the midsagittal slice and subdivided to 8 areas based on a method described by Witelson in 1989. The results indicated that the communication between the hemispheres in prefrontal lobe, motor area, somaesthetic area and inferior temporal lobe were poor in schizophrenia patients.

 

14:00         3551.     Gender Difference in Schizophrenia Revealed by Resting-State Functional MRI

Computer 50

Xiaoqi Huang1,2, Qihong Zou2, Wei Deng1, Su Lui1, Ling Zou1, Tijiang Zhang1, Xiuli Li1, Dongming Li1, Tao Li1, Yufeng Zang2, Qiyong Gong1

1West China Hospital of Sichuan University, Chengdu, People's Republic of China; 2Beijing Normal University, Beijing, People's Republic of China

Regional Homogeneity (ReHo) hypothesized that the time series of fMRI signals within a functional cluster are similar to each other£¬and it utilized KCC (Kendall's coefficient concordance) to measure this similarity in a voxel-wise way. Abnormal ReHo is possibly related to the changes of temporal aspects of neural activity in regional brain. The present study used ReHo method to study the gender difference in schizophrenia in brain activity at resting state which gave further evidence of gender effect on this illness from a functional perspective.

  

14:30         3552.     Alterations in BOLD Response and Metabolite Concentrations Support Decreased Glial Enzyme Activity in Major Depression: A Quantitative JPRESS and FMRI Study

Computer 50

Martin Walter1, Anke Henning2, Simone Grimm3, Rolf Feodor Schulte2, Johannes Beck3, Ulrike Dydak2, Betina Schnepf2, Heinz Böker3, Peter Boesiger2, Georg Northoff1

1Otto-von-Guericke University Magdeburg, Magdeburg, Germany; 2University and ETH Zurich, Zurich, Switzerland; 3University of Zurich, Zurich, Switzerland

Metabolic and functional alterations inside the pgACC were assessed by simultaneous quantitative in-vivo 2D-JPRESS measurements of GABA, glutamate and glutamine levels, fMRI measurements during emotional stimulation and subjective evaluation of the emotional state in healthy volunteers and patients with major depressive disorder (MDD). An altered excitation/inhibition balance was found. Changed neurotransmitter concentrations specifically relate to reduced deactivation, and altered subjective evaluation of emotional intensities and anhedonia scores in the patient group. In addition, a decreased activity of glial enzymes that are mediating the Glu reuptake from the synaptic cleft as well as the transformation of glutamate into glutamine is hypothesized.

 

15:00         3553.     White Matter Disruption in Early- And Late-Onset Depression: A Tract-Based Spatial Statistical Analysis

Computer 50

KiSueng Choi1, Richard Cameron Craddock2, Paul E. Holtzheimer1, Xiaoping Phillip Hu3, Helen S. Mayberg1

1Emory University School of Medicine, Atlanta, USA; 2Georgia Institute of Technology, Atlanta, USA; 3Emory University and Georgia Institute of Technology, Atlanta, USA

We used Track-Based Spatial Statistics to assess differences in WM FA associated with major depressive disorder. 23 subjects were classified into four groups (young & old controls, young early-onset & old late-onset major depression). A significant reduction was found between young patients and young controls in interesting region which is spatially approximate to a target proposed for deep brain stimulation for treatment resistant depression. No significant differences were found between older controls and old patients due to a large variance in FA resulting from brain atrophy. These results suggest that TBSS may be useful for comparing white matter integrity between clinically relevant populations.

 

13:30         3554.     1H MRS Neurochemical Predictors of Response to Intravenous Ketamine  in Treatment-Resistant Depression

Computer 51

Sanjay J. Mathew1, Rebecca B. Price1, James Murrough1, Marije Aan Het Rot1, Kate Collins1, Xiangling Mao2, David Reich1, Dennis Charney1, Dikoma C. Shungu2

1Mount Sinai School of Medicine, New York, New York, USA; 2Weill Medical College of Cornell University, New York, New York, USA

Twelve patients with treatment-resistant major depression were treated with open-label intravenous ketamine, an NMDA antagonist with rapid antidepressant effects. 1H-MRS scans completed prior to treatment revealed a positive association between concentrations of Glx/water in the occipital lobe and pre-treatment depression and anxiety scores. Lower occipital GABA/water was associated with superior treatment response 24 hours post-infusion. These findings add to a growing literature supporting the utility of neuroimaging measures as predictors of response to specific psychiatric treatments.

 

14:00         3555.     A Combined Functional-Structural Connectivity Analysis of Major Depression Using Joint Independent Components Analysis

Computer 51

KiSueng Choi1, Richard Cameron Craddock2, Paul E. Holtzheimer1, Zhi Yang3, Xiaoping Phillip Hu3, Helen S. Mayberg1

1Emory University School of Medicine, Atlanta, USA; 2Georgia Institute of Technology, Atlanta, USA; 3Emory University and Georgia Institute of Technology, Atlanta, USA

We integrated resting state functional connectivity (FC) and fractional anisotropy (FA) data in a joint ICA (Ranking and Averaging ICA by Reproducibility) to better characterize connectivity of the subgenual cingulate cortex in major depression. We examined 9 controls and 4 patients. The FC differences incorporate regions previously identified in a seed PLS analysis of a similar population and FA differences are spatially concordant with FC result areas suggesting that WM tracts connecting these regions may be different in depressed versus control subjects. These results indicate that disease related alterations in functional connectivity may be mediated by WM structural abnormalities.

 

14:30         3556.     A 1H Magnetic Resonance Spectroscopy Study in Adults with Obsessive Compulsive Disorder: Relationship Between Metabolite Concentrations and Symptom Severity

Computer 51

Maria Ljungberg1,2, Göran Starck1, Marie Nilsson, Lars Jönsson, Tord Ivarsson, Stefan Lundberg, Susanne Ribbelin11, Sven Ekholm, Arvid Carlsson, Eva Forssell-Aronsson1, Maria Carlsson

1Göteborg University, Göteborg, Sweden

Nine patients with moderate to severe OCD and 16 healthy controls were examined with 1H MRS (TE30ms) in three locations in the brain; the caudate nucleus, the anterior gyrus cinguli and the occipital cortex. The aim was to explore 1) metabolite concentration differences between patients and healthy volunteers, and 2) the relationship between metabolite concentrations and symptom severity in the patient group. LC Model and PCA-statistics was used for analysis. PCA did not reveal any separation between patients and controls with respect to MRS metabolites. However, PLS, disclosed a strong relationship between some of the metabolites and OCD symptom severity.

 

15:00         3557.     Regional Gray Matter Volume Abnormalities in Obsessive-Compulsive Disorder: A Study with the Automated Region-Of-Interest Measurement Method

Computer 51

Osamu Togao1, Takashi Yoshiura1, Tomoyuki Noguchi1, Akio Hiwatashi1, Koji Yamashita1, Eiki Nagao1, Tomohiro Nakao1, Maiko Nabeyama1, Hiroshi Honda1

1Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan

The purpose of this study was to assess regional gray matter (GM) volume abnormality in obsessive-compulsive disorder (OCD) using the automated region-of-interest method. The advantage of this technique is to be free from man-made technical bias, which is frequently seen in manual ROI method. We compared the regional GM volume between 24 OCD patients and 27 normal control subjects. This study revealed the GM volume abnormalities in the bilateral orbitofrontal cortex and the right anterior cingulated cortex. Results indicated that these structural abnormalities would be related to the pathophysiology of OCD.

 

13:30         3558.     Dysfunction of the Fronto-Striatal-Insular Network in Drug-Naive Adolescents with Attention Deficit Hyperactivity Disorder: A Resting-State FMRI Study

Computer 52

Xi-Nian Zuo1,2, Chao-Zhe Zhu2, Qing-Jiu Cao3, Vesa Kiviniemi4, Yu-Feng Wang3, Yu-Feng Zang2

1Institute of Automation, Chinese Academy of Sciences, Beijing, People's Republic of China; 2Beijing Normal University, Beijing, People's Republic of China; 3Peking University, Beijing, People's Republic of China

In this study, we investigated the fronto-striatal-insular network in boys with attention deficit hyperactivity disorder (ADHD) by using resting-state fMRI, which is believed to reflect spontaneous neuronal activity. Independent component analysis (ICA) was used to reveal the interested network. We found that boys with ADHD showed significantly decreased connectivity in the fronto-striatal-insular network compared to controls. This abnormal network was almost exclusively within the right hemisphere. By using a new technique (resting-state fMRI) and new analysis approach (ICA), the current results provided new evidence of fronto-striatal-insular network abnormality as well as right hemisphere abnormality in ADHD.

 

14:00         3559.     Decreased Functional Connectivity in the Brodmann Area 10 Network in Heroin Users

Computer 52

Wenjun Li1, Chunming Xie2,3, Xiuzhen Di2, Haiyan Meng2, Jun Xie1, Zhilin Wu1, Lin Ma4, Zheng Yang2, Shi-jing Li1

1Medical College of Wisconsin, Milwaukee, USA; 2Beijing Institute of Basic Medical Science, Beijing, People's Republic of China; 3Medical College of Southeast  University, Nanjing, People's Republic of China; 4P

Based on the results from Voxel-Based Functional connectivity MRI (fcMRI) using seed ROI approach has been widely used in current neurological research (e.g. in depression, schizophrenia, and Alzheimer’s disease). However, a dearth of literature has been published on heroin-related studies. The purpose of this study is to investigate the changes of functional connectivity (FC) changes between non-heroin participants and heroin abusers.  Based on the results from Voxel-Based Morphometry (VBM), we focus on how the decreased gray matter concentration in the region of Brodmann Area (BA) 10 could affect the FC in the brain of heroin users.

 

14:30         3560.     Impaired Frontal Executive Function in Abstinent Heroin Addiction: An FMRI Study

Computer 52

Li-ping Fu1, Yan Wang, Shi-jiang Li2, Guo-hua Bi1, Zhi-tong Zou, Xian Xu, En-mao Ye1, Lin Ma, Zheng Yang1

1Beijing Institute of Basic Medical Science, Beijing, People's Republic of China; 2Medical College of Wisconsin, Milwaukee, USA

Heroin impact negatively on the frontal cognitive function after repeated abuse. In this study, an fMRI method with Go-NoGo task was employed to detect the neuroanatomic substrates involved in inhibitory response in 18 healthy controls and to probe the frontal neurocognition of 30 protracted withdrawal heroin dependents. Our results demonstrated midline structure involved in response inhibition and impaired frontal executive function lasted even abstinence for two months. The disrupted frontal executive function maybe the common dominator for various substances abuse, which contribute to the vulnerability of heroin users to the conditioned cues, craving for drug and lead to relapse

 

fMRI: Acquisition Methods

Hall D                                   Monday 14:00-16:00                                                                                                                                             

14:00         3561.     Multi-Echo Parallel Imaging Accelerated FMRI with Susceptibility-Induced Off-Resonance Compensation

Computer 51

Heiko Schmiedeskamp1, Rexford David Newbould1, Klaas Paul Pruessmann2, Roland Bammer1

1Stanford University, Stanford, California , USA; 2University and ETH Zurich, Zurich, Switzerland

Off-resonance due to susceptibility effects typically results in signal dropouts if long echo times and/or thick slices are used such as for BOLD fMRI. To compensate for these effects, additional z-shim gradients can be applied. Here, parallel imaging shortened readouts allow multi-echo acquisitions, with varying z-shims prior to the echo trains. Whole-brain fMRI measurements can thereby be performed with minimized signal loss in dropout regions and no time penalty.

 

14:30         3562.     PAID FMRI at 7T - Investigating the Benefits of Multi-Echo EPI at High Field

Computer 51

Benedikt Andreas Poser1,2, David Gordon Norris1,2

1Radboud University, Nijmegen, Netherlands; 2University Duisburg-Essen, Essen, Germany

One drawback of commonly the used GE-EPI for functional brain imaging is that only one TE can be used. This implies a compromise in global functional sensitivity as optimal TE varies over the brain, due to considerable spread in gray matter T2*. To overcome this, the use of multi-echo EPI has been advocated, and shown to allow substantial sensitivity increases at 1.5 and 3T for various echo weighting strategies. Here in we investigate the value of parallel-acquired inhomogeneity desensitized (PAID) fMRI at 7T. Initial experiments show that CNR benefits are obtained across the brain, and hat distortion is markedly reduced.

 

15:00         3563.     Highly Accelerated FMRI: A Feasibility Test of Image Support Reduction Technique

Computer 51

Feng Huang1, Hu Cheng2, Yu Li1

1Invivo Corporation, Gainesville, Florida, USA; 2Indiana University, Bloomington, Indiana, USA

Feasibility of the application of image support reduction technique for fMRI is reported. Experimental results show that active regions can still be accurately detected at acceleration factor as high as 4 with image support reduction technique. Therefore, image support reduction can be adopted in fMRI to achieve images with higher spatial resolution.

 

15:30         3564.     Increasing Spatial Coverage for High Resolution FMRI Studies

Computer 51

Yanle Hu1, Gary H. Glover2

1University of Texas at Austin, Austin, Texas, USA; 2Stanford University, Stanford, California , USA

A novel technique which combines the 3D acquisition method with the UNFOLD technique is proposed to increase spatial coverage for high resolution fMRI studies. Theoretical analysis based on a thermal noise model shows that compared to the traditional method, the proposed method can acquire more slices at a similar SNR performance given the same volume TR and total scan time. A comparison study performed on normal volunteers confirmed our theory.

 

14:00         3565.     Hemodynamic Properties of Passband B-SSFP FMRI

Computer 52

Jin Hyung Lee1, Gary H. Glover1, Taeksoo Kim1, Dwight G. Nishimura1, John M. Pauly1

1Stanford University, Stanford, California , USA

Passband b-SSFP fMRI shows great promise with its distortion-free, high-resolution imaging capabilities. In this paper, we present quantitative results on the contrast and temporal dynamics of passband b-SSFP fMRI.

 

14:30         3566.     Considerations on Scan Parameters in Passband SSFP FMRI

Computer 52

Taek Soo Kim1, Jongho Lee,12, Jin Hyung Lee1, Gary H. Glover1, John Mark Pauly1

1Stanford University, Stanford, California , USA; 2National Institute of Health, Bethesda, Maryland, USA

Passband SSFP fMRI generates higher functional contrast in relatively short TRs, providing the potentials for high-resolution fMRI. Moreover, it can emphasize the signal from capillaries in the extravascular space and has a potential to better localize the activation area. As shown in previous studies, the functional contrast and the signal to noise ratio in balanced SSFP fMRI are functions of MR parameters. However, its optimal scan parameters have not been investigated systematically. In this study, we suggest a guideline for selecting the scan parameters for passband SSFP fMRI.

 

15:00         3567.     High Resolution 3D Functional Images of the Human Olfactory Bulb Using Passband SSFP at 3T

Computer 52

Todd B. Parrish1, YuFen Chen1, Wen Li1, James Howard1, Jay A. Gottfried1

1Northwestern University, Chicago, Illinois, USA

A novel new passband SSFP sequence is used to acquire high resolution (1x1x2mm), artifact free fMRI images of the human olfactory bulb at 3T during an odor detection task. The implementation of the 3D FISP sequence provided similar contrast to standard EPI BOLD when the two imaging methods were compared in the motor cortex. The importance of imaging the bulb is equivalent to imaging V1 in the visual system, since it is the first level of input. The ability to obtain fMRI data of the bulb will further the understanding of the olfactory system.

 

15:30         3568.     T2-Weighted, 3D Whole Brain FMRI at 3 T and 7 T Using S2-SSFP

Computer 52

Markus Barth1,2, Stephan A. Kannengiesser3, Heiko Meyer3, David G. Norris1,2

1Radboud University, Nijmegen, Netherlands; 2University Duisburg-Essen, Essen, Germany; 3Siemens Medical Solutions, Erlangen, Germany

In this abstract it is shown that the S2-SSFP signal represents a viable alternative to spin-echo EPI for fMRI at both 3 and 7T. In order to achieve the necessary temporal resolution a 3D acquisition scheme combined with acceleration along two spatial axes was employed. Functional data showed good spatial localisation and sensitivity while avoiding both image distortion, and problems of power deposition. In conclusion whole-brain fMRI at 7Tesla will be possible using the S2-SSFP sequence and partial parallel imaging.

 

14:00         3569.     High Resolution FMRI Using Short Axis Readout Propeller EPI (SAP-EPI)

Computer 53

Anders Nordell1, Samantha Holdsworth2, Rexford Newbould2, Roland Bammer2, Stefan Skare2

1Karolinska University Hospital, Stockholm, Sweden; 2Stanford University, Palo Alto, California , USA

Short Axis readout propeller EPI (SAP-EPI) is a T2*-weighted sequence well suited for BOLD imaging. SAP-EPI has properties that enable high resolution imaging, while maintaining good volume coverage and dynamic resolution. This study investigates the reproducibility of the BOLD response using a simple fMRI stimulus and compares high resolution SAP-EPI to conventional ssEPI at high and low resolution.

 

14:30         3570.     Evaluation of K-T BLAST Applied to Spin-Echo Based BOLD Functional MRI [Not Available]

Computer 53

Jane Frances Utting1,2, Rani Bhaninny1, René Vohn1, Ralph Schnitker1, Sebastian Kozerke2, Thoralf Niendorf1

1RWTH-Aachen, Aachen, Germany; 2University and ETH Zuerich, Zuerich, Switzerland

Motivated by the prospect of anatomically accurate fMRI using spin-echo based imaging, with acquisition times and RF power deposition reduced by applying spatio-temporal correlation techniques (k-t BLAST), this study was designed to investigate the temporal fidelity of k-t accelerated displaced UFLARE applied to BOLD contrast fMRI. Controlled temporal variations in signal intensity in a test object and fMRI in subjects performing a block motor paradigm demonstrate the feasibility of applying k-t acceleration to fMRI and the importance for temporal fidelity of including training data in k-t BLAST reconstructions.

 

fMRI: Animal Models

Hall D                                   Monday 14:00-16:00                                                                                                                                             

14:00         3571.     The Effects of Ambient MRI Scanner-Generated Auditory Noise on Rat Auditory Perception at 9.4T

Computer 54

Conny Frauke Schmidt1, Bing Wen Zheng1, Steven Graham2, Xavier Golay1,3

1Biomedical Sciences Institutes, Singapore, Singapore; 2National University of Singapore, Singapore, Singapore; 3National Neuroscience Institute, Singapore, Singapore

This study investigated the effects of acoustic scanner noise on auditory perception and processing in the rat.  Using a steady-state clustered-sparse temporal acquisition (ssCTA) protocol that allowed 'silent' fMRI scanning we avoided interference with acoustic noise which is produced by the scanner during echo planar imaging (EPI), similar to the spare-temporal designs employed in human auditory fMRI studies. We then introduced 4-s acoustic “EPI-like” stimuli to examine the effects of acoustic scanner noise on auditory perception.

 

14:30         3572.     Auditory Selectivity for Species and Self Recognition in the Zebra Finch Brain: New Insights from Spin-Echo BOLD FMRI

Computer 54

Colline Poirier1, Tiny Boumans1, Marleen Verhoye1,2, Jacques Balthazart3, Annemie Van der Linden1

1Bio-Imaging Lab, Antwerp, Belgium; 2Vision Lab, Antwerp, Belgium; 3Ctr. Cell. Molec. Neurobiology, Belgium

2006-... Post-doc position in Bio-Imaging Lab, University of Antwerp, Belgium (auditory fMRI in zebra finches)

2005: PhD in Neurosciences, GREN laboratory, University of Louvain, Belgium ( PhD thesis: Auditory perception and sensory substitution: a neuro-ethological approach.

2000: Master in Behavioral biology, University of Paris13/University of Rennes1 (Master thesis: Effects of social experience on song learning in starlings).

  

15:00         3573.     Functional MRI of the Rat Spinal Cord in Painful Diabetic Neuropathy

Computer 54

Cheryl Jones1, Paul Fernyhough2, Nigel Calcutt3, Krisztina Laura Malisza4

1University of Winnipeg, Winnipeg, Canada; 2University of Manitoba, Winnipeg, Canada; 3UCSD, La Jolla, USA; 4National Research Council Institute for Biodiagnostics, Winnipeg, Canada

This study shows that fMRI of the spinal cord has promise for the detection of early onset diabetic neuropathy. FMRI of the spinal cord was conducted in healthy controls and streptozotocin (STZ) diabetic rats using electrical and formalin stimulation. Greater fMRI activity was observed in STZ animals during 0.2% formalin injection and greater percentage signal change occurred in diabetic animals with both 0.2% and 5.0% formalin injection. This demonstrates the hypersensitivity in these animals. Less activity was observed in the dorsal horn during noxious electrical stimulation in STZ rats compared to controls, suggesting neuronal fibre dysfunction.

 

15:30         3574.     Modality-Specific Frequency Dependency of the Rat Somatosensory Cortex Assessed by FMRI

Computer 54

Basavaraju Ganganna Sanganahalli1, Peter Herman1, Fahmeed Hyder1

1Yale University, New Haven, Connecticut, USA

We investigated the frequency-dependent activation of the rat somatosensory cortex at 11.7T for two sensory modalities (whisker and forepaw). We observed linear increase in the BOLD response with increasing frequencies up to 12 Hz and showed saturation at higher frequencies during whisker stimulation. On the contrary the magnitude of BOLD response for forepaw stimulation was largest at 1.5 Hz and decreased with increasing frequencies. These results demonstrate differences in the frequency dependent behavior during forepaw and whisker stimulations and provide a model for studying coupling between neuronal activity and blood flow across the different somatosensory regions.

 

fMRI: Non-BOLD & MT

Hall D                                   Tuesday 13:30-15:30                                                                                                                                             

13:30         3575.     Volumetric Blood Flow Rate Measurement by Flow ENhancement of Signal Intensity (FENSI)

Computer 51

Cheng Ouyang1, Dimitrios Karampinos1, John G. Georgiadis1, Brad P. Sutton1

1University of Illinois at Urbana-Champaign, Urbana, Illinois, USA

Blood flow changes are believed to be more directly related with brain activation than blood oxygenation techniques, especially flow in microvessels (arterioles, capillaries, and venules). In this work, we applied the method Flow ENhancement of Signal Intensity (FENSI) to measure quantitative information on microvascular volumetric flow rates at baseline level and during a functional visual task. Besides providing accurate measurements of blood flow, FENSI also possesses high spatial localization and directional sensitivity.

 

14:00         3576.     Highly Conserved CBF/CMRO2 Coupling in Human Primary Visual Cortex for Chromatic and Luminance Stimuli

Computer 51

Oleg Leontiev1,2, Giedrius T. Buracas2, Christine Liang2, Joanna E. Perthen2, Beau M. Ances2, Richard B. Buxton2

1Exempla St.Joseph Hospital, Denver, Colorado , USA; 2University of California, San Diego, La Jolla, California , USA

We conducted a systematic set of experiments designed to optimize the sensitivity for detecting a difference in CBF/CMRO2 coupling to criticially test the hypothesis of uniform coupling for chromatic and luminance stimuli in human primary visual cortex (V1). CBF/CMRO2 coupling in V1 was very similar for the chromatic and luminance stimuli used, suggesting a consistent coupling for Cytochrome-oxidase (CO) blob and inter-blob regions despite differences in CO concentration.

 

14:30         3577.     Dependence of Functional ASL MRI Signal on Number of Slice Acquisitions

Computer 51

Ajna Borogovac1, John W. Krakauer, Truman R. Brown, Iris Asllani

1Columbia University, New York, New York, USA

We present experimental data from motor stimulation showing a dependency of ASL functional SNR on the number of acquisition slices. Both resting and activation group-average CBF values were higher for partial coverage as compared to the whole brain acquisition. Also, the number of activated voxels was ~50% higher for the smaller imaging volume. However, whole brain acquisition showed a more complete localization of activation by detecting areas in the cerebellum associated with motor stimulation.

 

15:00         3578.     Implicit Learning–related Effects Detected by Optimized ASL FMRI

Computer 51

María A. Fernández-Seara1, Maite Aznárez-Sanado1, Francis Loayza1, Maria A. Pastor1

1Center for Applied Medical Research, University of Navarra, Pamplona, Spain

An optimized ASL technique was used to study changes in neural activity with motor learning. This sequence combines pseudo-continuous labeling with a background suppressed single shot 3D GRASE readout. The increased sensitivity of the sequence allowed detection of implicit learning effects at the group level.

 

13:30         3579.     Quantification of Cerebral Blood Volume During Brain Activation with Grey Matter Nulled FMRI

Computer 52

Yuji Shen1, Ida Mengyi Pu2, Risto A. Kauppinen3

1University of Birmingham, Birmingham, UK; 2Goldsmiths, University of London, London, UK; 3Dartmouth Medical School, Hanover, USA

Grey matter nulled (GMN) fMRI is a new fMRI technique that reveals changes in CBV associated with brain activation. The GMN fMRI is prone to errors in estimation of absolute CBV due to partial volume effect of CSF. In this study, we present a technique to quantify CBV both in baseline and during activation by determining CSF fraction in MRI voxels. A set of GMN fMR images was acquired with multiple TRs to fit data into a model comprising of multiple parenchymal compartments. CBV at baseline and during visual stimulation was found to be 5.5±0.04 and 7.8±0.08 ml/100 ml, respectively.

 

14:00         3580.     Simultaneous Acquisition of BOLD and VASO Signals Using Looker-Locker Method

Computer 52

Wen-Chau Wu1,2, Felix W. Wehrli2

1National Taiwan University, Taipei, Taiwan; 2University of Pennsylvania, Philadelphia, USA

In this study, we use the Look-Locker (LL) sequence to simultaneously measure BOLD and VASO signals during epochs of visual stimulation. LL images were binned by TI and analyzed separately, which led to ten sets of time series data (L1,L2,...,L10), each with a temporal resolution of 4 s. The varied weighting of BOLD and VASO signals at different TI's may help understanding of VASO signal source and extra- vs. intra-vascular BOLD. Flow information may be extracted by modeling the signals at L10 versus L1.

 

14:30         3581.     Enhancing Relative BOLD Signal Changes Using Magnetization Transfer (MT)

Computer 52

Jun Hua1, Manus J. Donahue1, Seth A. Smith1, Peter C.M. van Zijl1, Jinyuan Zhou1

1Johns Hopkins University School of Medicine, Baltimore, Maryland, USA

We show that the BOLD signal change can be increased by adding an off-resonance MT pre-pulse to the BOLD sequence that suppresses the pure tissue signal. This is due to an increase in the relative contribution from blood (intravascular BOLD). The relative enhancement ranges from 30% to 50%. Thus MT-BOLD can employ a shorter TE than normal BOLD with comparable contrast to noise ratio. The relative signal changes from a pair of MT-BOLD and BOLD experiments can be used to calculate the extravascular contribution to the BOLD effect, which was found to be 65%±8% at a field strength of 3T.

 

15:00         3582.     Using Magnetization Transfer (MT) to Enhance SNR and CNR for VASO MRI

Computer 52

Jun Hua1, Manus J. Donahue1, Jason M. Zhao1, Ksenija Grgac1, Alan J. Huang1, Jinyuan Zhou1, Peter C.M. van Zijl1

1Johns Hopkins University School of Medicine, Baltimore, Maryland, USA

Vascular Space Occupancy (VASO) fMRI employs tissue signal changes during blood nulling to image blood volume changes. It has low tissue SNR due to the small remaining tissue signal (10-20% of normal). We show here that adding an MT pulse before or after the VASO inversion pulse can attenuate the initial tissue magnetization before inversion or accelerate the recovery process after inversion, respectively. This leads to increased tissue signal intensity at the time of blood nulling, drastically improving SNR (~50% and 40%, respectively). Since relative VASO signal changes are unchanged, the CNR can be enhanced by ~45% and 35%, respectively.

 

fMRI: Neuroscience

Hall D                                   Tuesday 13:30-15:30                                                                                                                                             

13:30         3583.     Cerebral Response to Different Voice Production: A Functional Magnetic Resonance Imaging Study

Computer 53

Kyung K. Peck1, Jessica Galgano, Ryan Branski, Merge Ho, Andrei Holodny, Dennis Kraus1

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

The neural correlates of laryngeal movement for voice production at comfortable as well as other pitch levels remain poorly characterized. This is due, in part, to difficulties controlling for experimental confounds between the sensorimotor and cognitive-linguistic aspects of speech phonation/voicing. Thus, investigations aiming to isolate the neural mechanisms of voice production, and in particular, pitch modulation, can be a particular challenge. The current study seeks to describe the central mechanisms responsible for voice production in healthy subjects using functional magnetic resonance imaging (fMRI).

 

14:00         3584.     The High Incidence and Bioethics of Findings on MR Brain Imaging of Normal Volunteers for Neuroscience Research

Computer 53

Nigel Hoggard1, Gail Darwent1, David Capener1, Iain Wilkinson1, Paul Griffiths1

1University of Sheffield, Sheffield, UK

Over the past decade there has been a huge expansion of interest in functional MR imaging of the brain for neuroscience research and it is capturing the interest of the general public. Illes has estimated that between 1991 and 2000 using fMRI as the keyword search that there may have been at least 30000 research participants in fMRI studies in the published literature. We have found a high rate of incidental abnormalities (8.8%) amongst individuals participating in imaging studies at our institution. We believe  that in medical research imaging a there is a duty of care to the participants and that neuroradiological review should be performed and if sugnificant pathology discovered the participant should be informed, counselled and their primary care physician informed to allow the participant to be able to discuss findings over time and recieve advice independent of the research team.

 

14:30         3585.     Judgment of Moral Certainty:  Developmental FMRI Patterns

Computer 53

Melissa Ann Long1, Paul Joseph Eslinger1, Jianli Wang, Jennifer Realmuto, Fernanda Moll, Jorge Moll, Qing Yang

1Penn State College of Medicine, Hershey, Pennsylvania, USA

Moral judgment (MJ) is defined as the capacity to make decisions and judgments which are moral and to act in accordance with such judgments (Kholberg 1964).  MJ is crucial in guiding social behavior.  A better understanding of MJ and its development will be innovative in promoting MJ’s that foster pro-social emotions and behavior and attenuate anti-social emotions and behavior, which are the root of numerous social disorders/diseases and their associated pain, diminished quality of life, and vulnerability to criminal behavior (Stams et al. 2006).  Several adult fMRI studies have investigated MJ in the brain, but none to our knowledge, have investigated MJ and its development in children.  Utilizing fMRI, we conducted an experiment demonstrating the neural uderlyings of children's responses to sentences that contained moral content and were chosen by the child to be either "right" or "wrong."  Resulting brain activations patters indicated that most acitvations were similar to that of adult studies.  Areas of activation were in the frontal regions and the posterior temporal regions of the brain.

 

15:00         3586.     Analysis of the Effect of Magnetic Fields on the Amplitudes of the Early and Late Cognitive Potentials During FMRI

Computer 53

Sirel Karakas1,2, Hakki Muammer Karakas,23, Zeynel Baran1,2, Arzu Ozkan-Ceylan1,2, Elvin Dogutepe-Dincer1,2, Turgut Tali,24

1Hacettepe University, Ankara, Turkey; 2Turkish Multicenter Research Group on Cognitive Neurosciences, (TURCONS), Turkey; 3Inonu University, Kampüs, Turkey; 4Gazi University, Turkey

MRI-EEG studies provides simultaneously recorded structural, hemodynamic and electrophysiological data. The aim was to investigate the magnitude of the contaminating ballistocardiogram artifact during fMRI recording on specifically the earlier ERP component and to provide information on the reliability of MRI-EEG technique. A 1.5 T scanner with high resolution coil, coupled with MR-compatible 64-channel EEG and stimulation hardware was used. The study showed that the early and late peaks on the ERP were comparably obtained in standard EEG lab and in the scanner. The previously reported attenuation of some ERP peaks was found to be the result of inter-individual latency jitter.

 

13:30         3587.     Effect of Intravenous Lidocaine on Brain Activation During Non-Noxious and Acute Noxious Stimulation of the Forepaw: A Functional MRI Study in the Rat

Computer 54

Zhongchi Luo1, Mei Yu1, S, David Smith2, Mary Kritzer1, Yu Ma1, Congwu Du1, Nora D. Volkow3, Peter S. Glass1, Helene Benveniste,12

1Stony Brook University, Stony Brook, New York, USA; 2Brookhaven National Laboratory, Upton, New York, USA; 3NIH, Bethesda, Massachusetts, USA

We investigated the analgesic action of systemic lidocaine on the brain's responses to acute pain. We showed that its action is not related to a straight forward interruption of pain-induced brain activation as has been observed with opioids. We also found that lidocaine enhanced cortical responses to acute pain similar as what has been reported for cocaine. We recently showed that both lidocaine and cocaine increased intracellular calcium concentrations in cortex suggesting that this pharmacological effect could account for the enhanced sensitivity to somatosensory stimulation. As our model only measured physiological acute pain it will be important to also test the response of these same pathways to lidocaine in a model of neuropathic pain to determine lidocaine’s analgesic mechanism of action.

 

14:00         3588.     Reproducibility and Sensitivity of Pain-Related FMRI-BOLD Activation Responses Due to Noxious Nd:YAP Laser Stimulation: A Possible Tool for Analgesic Drug Discovery

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Catherine Elizabeth Warnaby1, Ricardo Jose Governo1, Iain Robert Wilson1, Paul M. Matthews2,3, Irene Tracey1

1University of Oxford, Oxford, UK; 2GlaxoSmithKline, London, UK; 3Imperial College, London, UK

A parametric laser-FMRI study was performed to investigate the sensitivity and reproducibility of BOLD responses to pain-related brain activity. During three experimental sessions, laser stimuli were delivered at intensities corresponding to the individual’s perception of low, medium and high pain. Subjective pain ratings were recorded after each stimulus and despite non-significant changes in pain ratings across sessions the FMRI was sensitive enough to detect significant differences that correlated with minor non-significant changes in pain ratings. Early results suggest that BOLD-FMRI can potentially provide a more objective and robust marker of pain perception than the subjective pain report.

 

14:30         3589.     Studying Pain Transmission with BOLD FMRI: Thermal vs. Electrical Stimulation

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Arthur Peter Wunderlich1, Gregor Stuber1, Roland Klug2, Wolfgang Freund1

1Univ.-Clinic Ulm, Ulm, Germany; 2Rehabilitation Clinic Ulm, Ulm, Germany

In order to study the feasibility to distinguish different pathways of pain transmission, we acquired 15 healthy subjects each for thermal and electrical stimulation. During fMRI, subjects were stimulated in blocks of three different intensities and no stimulation as reference condition in pseudorandomized order. Attention of subjects was focused to sensation advising them to rate stimulus intensity. Data were analysed in SPM. Contrasts of all intensities against rest were calculated and compared between both modalities in a second-level analysis. Differences in cortical and subcortical activation were found, which can be interpreted as consequence of different pathways activated by stimulus modalities.

 

15:00         3590.     Semantic Memory in the Anterior Temporal Lobes: A New Distortion Correction Method for FMRI

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Maya Visser1, Karl Victor Embleton1, Elizabeth Jefferies1,2, Geoff J. Parker1, Matthew A. Lambon Ralph1

1University of Manchester, Manchester, UK; 2University of York, York, UK

The neural substrate of semantic memory is a topic of considerable debate. Patients with semantic dementia show a highly specific impairment of semantic memory, associated with atrophy in the anterior temporal lobes (ATL) bilaterally, suggesting that this is the critical neural substrate for semantic memory. However, most fMRI studies do not observe ATL activation during semantic processing because the signal is distorted and/or suppressed in these areas. We used a new distortion correction for fMRI to investigate brain activation during semantic processing. This method revealed bilateral ATL activation during semantic processing, providing convergence with evidence from patients with semantic dementia.

 

13:30         3591.     Identical Stimuli But Different Cortical Activations: FMRI Study on Active and Passive Oddball Tasks

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Hakki Muammer Karakas1,2, Sirel Karakas,23, Turgut Tali,24

1Inonu University, Kampüs, Turkey; 2Turkish Multicenter Research Group on Cognitive Neurosciences, (TURCONS), Turkey; 3Hacettepe University, Ankara, Turkey; 4Gazi University, Ankara, Turkey

Cognitive requirements of the passive oddball paradigm task is auditory memory and preattentional change detection. On the other hand, the cognitive requirements of the active oddball paradigm task include these three processes and also focused attention, working memory, stimulus recognition and decision for the response to be made. This fMRI study was conducted to reveal differential activation caused by these tasks. They both produced activation in auditory cortex and its vicinity. However, only the active oddball task led to activation in the general integration area and in the frontal lobes, an event that cannot be detected with electrophysiological methods.

 

14:00         3592.     Modulation of Human Mirror Neuron System by Task Complexity and Laterality

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Michela Tosetti1, Andrea Guzzetta1, Laura Biagi1, Elisa Petacchi1, Serena Galiberti1, Leonardo Fogassi2, Giovanni Cioni1,3

1Stella Maris Scientific Institute, Pisa, Italy; 2University of Parma, Italy; 3University of Pisa, Pisa, Italy

We studied the Mirror Neuron circuit in twelve right-handed healthy volunteers. The anterior intraparietal cortex was activated by the observation of external actions according to the identity of the observed hand and to the complexity of the hand action. These findings support the hypothesis of a specific role of anterior intraparietal cortex in the final steps of visuo-motor transformation.

 

14:30         3593.     Brain Activation Associated with Subliminal Reading Stimuli in Dyslexics and Normal Readers – an FMRI Study

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Tammar Kushnir1, Shani Fishman1, David Manor1,2

1The Chaim Sheba Medical Center, Tel Hashomer, Israel; 2Haifa University, Haifa, Israel

Compatibility effect (CE) is a modulation of the motor response time to a target stimulus by a preceding prime stimulus that is either compatible or incompatible with the target stimulus. CE has been found for subliminal masked prime. The present study investigated CE on behavioral and associated brain activity in dyslexic and non dyslexic subjects, using a subliminally priming reading stimulus. The brain activity was evaluated using functional MRI (fMRI). Behavioral and brain activity results indicated that CE and the perception and processing of a subliminal stimulus in the right hemisphere were stronger in the dyslexic subjects.

 

15:00         3594.     Task Difficulty Differences with Age in a Functional MRI Verb Generation Task

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

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

Previously, we have shown that subject-specific categorization of task difficulty can be used to identify differential recruitment in the standard language areas with change in difficulty, using a verb generation fMRI task. The goals of this study were: 1. to evaluate the differences in functional recruitment with task difficulty, between younger and older subjects, and 2. to quantify between group and between individual variability of activation with task difficulty. Of particular interest is the quantification of individual subject task difficulty, which has specific implications for studying brain plasticity in patients where population-based inferences are less important.