Electronic Posters : Neuroimaging
Click on to view the abstract pdf and click on to view the video presentation.
Head & Neck MRI (including Cancer)

Monday May 9th
Exhibition Hall  14:00 - 16:00 Computer 107

14:00 4274.   Real-Time 3D Motion Correction for High-Resolution MR Imaging of the Larynx 
Joëlle Karine Barral1, Juan M Santos2, Edward J Damrose3, Nancy J Fischbein3,4, and Dwight G Nishimura5
1Bioengineering, Stanford University, Stanford, CA, United States, 2Heart Vista, Inc., Los Altos, CA, United States, 3Otolaryngology, Stanford University, Stanford, CA, United States, 4Radiology, Stanford University, Stanford, CA, United States, 5Electrical Engineering, Stanford University, Stanford, CA, United States

Motion is the main limitation to in vivo, high-resolution larynx MR imaging. A new real-time motion-compensation algorithm is introduced, which extends the Diminishing Variance Algorithm (DVA) to improve its robustness. Navigator data are processed in real time to compute rigid-body motion, and projections are corrected using phase modulation in k-space. Upon automatic feedback, the system immediately reacquires the data most heavily corrupted by non-rigid motion, i.e., the data whose corresponding projections could not be properly corrected using phase modulation. Larynx imaging was performed on healthy volunteers, and substantial reduction of motion artifacts caused by bulk shift, swallowing, and coughing was achieved.

14:30 4275.   Automatic Generation of Movie with Sound during Speech Production for Assessing Velopharyngeal Insufficiency 
Andre J.W. van der Kouwe1, Pallavi Sagar2, Amanda L Silver3, Stephen Maturo3, Katherine Nimkin2, and Christopher J Hartnick3
1Athinoula A. Martinos Center, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States, 2Pediatric Radiology, Department of Radiology, Massachusetts General Hospital, Boston, MA, United States, 3Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA, United States

Velopharyngeal Insufficiency (VPI) is a condition in which the velopharynx does not properly close during speech production. The condition can be improved with surgery after evaluation with videofluoroscopy and/or nasendoscopy. MRI may provide a non-invasive and non-radiative alternative. We present a protocol for acquiring two images per second of the velopharyngeal anatomy during speech production and a method implemented on the scanner for automatically generating an mpeg movie from the image series along with a synchronized audio recording using an optical microphone. The movie is available for review on the scanner immediately after imaging.

15:00 4276.   Efficient CSF Flow Imaging with a Multiple Flexible Labeling Band Sequence at 3.0T 
Hao Shen1, Nan Sun2, Guang Cao3, Jinfeng Li4, and Ailian Zhang4
1Global Applied Science Laboratory, GE Healthcare, Beijing, Beijing, China, People's Republic of, 2MR Modality, GE Healthcare, Beijing, Beijing, China, People's Republic of,3Global Applied Science Laboratory, GE Healthcare, Hong Kong, China, People's Republic of, 4Department of Radiology, Chinese PLA General Hospital, Beijing, Beijing, China, People's Republic of

The cerebrospinal fluid flow imaging has been used to diagnose several diseases in the clinical practice. In this study, we developed a sequence with multiple flexible labeling bands to visualize the CSF flow based on the concept of time-spatial labeling inversion pulse. Phantom study and human study were both done at a 3.0T scanner. The sequence can image the CSF flow of the aqueduct and foramen magnum simultaneously and improve the scan efficiency.

15:30 4277.   Brain MRI Segmentation for Focal Cortical Dysplasia Lesion Detection 
Ivana Despotovic1, Ief Segers1, Ljiljana Platisa1, Ewout Vansteenkiste1, Aleksandra Pizurica1, Karel Deblaere2, and Wilfried Philips1
1Department of Telecommunications and Information Processing TELIN-IPI-IBBT, Ghent University, Ghent, Belgium, 2Department of Radiology, Ghent University Hospital, Ghent, Belgium

Focal cortical dysplasia (FCD) is a major cause of refractory epilepsy and is characterized with subtle brain lesions. Identification of FCD lesions using MRI scans is the first and most difficult step in medical treatments. Most of the existing FCD detection algorithms are based on cortical thickness measurement, which requires brain MRI segmentation. In this work, we propose an improved technique for 3D brain MRI segmentation based on graph cuts algorithm. The performance of our algorithm is validated on both phantom and real patient MRI. Experimental results show that our method is effective and successfully indicates the FCD lesions.

Tuesday May 10th
  13:30 - 15:30 Computer 107

13:30 4278.   Effects of Nonrigid Registrations on DBM Analysis Using SSD Model 
Zhaoying Han1,2, Xue Yang1, Bennett A Landman1,2, John C Gore2, and Benoit M Dawant1
1Electrical Engineering, Vanderbilt University, Nashville, TN, United States, 2Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States

Deformation Based Morphometry (DBM) aims to detect morphological differences between groups based on statistical analysis of deformation fields generated by non-rigid registrations. Few studies have compared the effects of registration algorithms on DBM. We simulated two groups of normal brain images and deformation fields using the Statistical Simulation of Deformations (SSD) model, introduced known growths in one group, and evaluated the effect of five non-rigid registration methods (ABA, IRTK, FSL, ART, and SPM normalization) on DBM analysis of the groups without and with growths. The “ground truth” Jacobian map from the known growths was used as the basis for comparison.

Marc LABROUSSE1,2, Guillaume CALMON1, Gabriela HOSSU1,3, André CHAYS2, Jacques FELBLINGER1, and Marc BRAUN1,4
1IADI, INSERM U947, NANCY, France, 2Faculty of Medecine and University Hospital, REIMS, France, 3CIC-IT NANCY (INSERM CIT801), NANCY, France, 4Faculty of Medecine and University Hospital, NANCY, France

Phase-contrast MRI was used at the level of the cerebello-pontine angle in 28 volunteers to measure the cranio-caudal and antero-posterior motion of the cisternal, meatic part of the vestibulo-cochlear nerve (VCN), and the pons. ROIs were manually drawn on T2 sequences. VCN motion is a cardiac-cycle-dependent movement like brain motion. We made a “string oscillated” model of the VCN explaining the differences between the amplitudes of the cisternal and meatic parts. Phase contrast MRI can be used to assess the VCN motion at the level of the cerebello-pontine angle.

14:30 4280.   Diffusion-weighted Zoomed EPI of the larynx and oral cavity/oropharynx 
Daniel Guo Quae Chong1, Dechen Wangmo Tshering Vogel1, Josef Pfeuffer2, Andre de Oliveira2, Berthold Kiefer2, Johnannes Micheal Froehlich1,3, and Harriet Thoeny1
1Dept. of Diagnostic, Interventional and Pediatric Radiology (DIPR), Inselspital, Bern, Switzerland, 2Siemens AG, Erlangen, Germany, 3Guerbet AG, Zurich, Switzerland

Zoomed-EPI was compared with conventional EPI for imaging of the larynx and oral cavity/oropharynx being regions highly susceptible for artifacts, but with a high incidence of tumors warranting a reliable DW-MRI technique. Zoomed-EPI allows a reduced field of view readout scheme leading to a reduced phase evolution induced by the local field inhomogeneities. The aim of our study was to prospectively compare both EPI and Zoomed-EPI at 3T for DW-MRI of the larynx and oral cavity/oropharynx. Our results show that Zoomed-EPI provides less distortion artifacts, higher resolution in equal scan time and similar resultant ADC values.

15:00 4281.   Comparison of vascularity characteristics between primary tumor and metastatic nodes in head and neck cancer by DCE- and IVIM-MRI 
Yonggang Lu1, Jacobus F.A. Jansen2, Hilda E Stambuk1, Nancy Lee1, Jason A. Koutcher1, and Amita Shukla-Dave1
1Memorial Sloan-Kettering Cancer Center, New York, NY, United States, 2Maastricht University Medical Center, Maastricht, Netherlands

This study compares DCE- and IVIM- MRI derived parameters reflecting tumor vascularity between the primary tumor and neck nodal metatases. The initial results with twelve patients revealed that metastatic nodes have significant higher diffusion coefficients (ADC-apparent diffusion coefficient and D-pure diffusion coefficient) than primary tumors but showed no significant difference in perfusion properties. Additionally, a significant correlation of parameters D and ve (extravascular extracellular space) between primary tumor and neck nodal metastases was observed. These findings after validation in larger patient population and with appropriate molecular correlates may provide better understanding of the underlying tumor biology, and help in treatment planning.

Wednesday May 11th
  13:30 - 15:30 Computer 107

13:30 4282.   Coil Comparison for In Vivo Eye Imaging at 7T 
Peter A Wassenaar1, Kathryn Richdale2, Petra Schmalbrock1, and Michael V. Knopp1
1Wright Center of Innovation, Department of Radiology, The Ohio State University, Columbus, OH, United States, 2College of Optometry, The Ohio State University, Columbus, OH, United States

Imaging of the human eye is important in the assessment of ocular diseases. With the introduction of eye imaging at 7T comes increased signal and higher resolution visualization of the orbit and ocular structures. This work compares different single loop receive coils for in vivo eye imaging at 7T. It is shown that a small custom-built coil provides the best approach for imaging the lens and ciliary body, while slightly larger coils are best suitable for imaging of the retinal wall and retro-bulbar structures.

14:00 4283.   High resolution distortion-free diffusion-tensor imaging of craniovertebral junction 
Mami Iima1, Akira Yamamoto1, Tomohisa Okada1, Mitsunori Kanagaki1, Denis Le Bihan2,3, Seiko Kasahara1, Emiko Morimoto1, Satoshi Nakajima1, Ryo Sakamoto1, Taha Mohamed Mehemed1, and Kaori Togashi1
1Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan, 2Human Brain Research Center, Kyoto University Graduate School of Medicine, Kyoto, Japan, 3Neurospin, CEA-Saclay Center, Gif-sur-Yvette, France

We implemented GRAPPA-accelerated RS-EPI DTI and SS-EPI DTI at 3T MR scanner with 32-channel head coil, and evaluated the feasibility of clinical application by comparing these two acquisition methods. RS-EPI has much reduced susceptibility compared with SS-EPI and can be a potential to be an alternative to SS-EPI DTI for evaluating CVJ lesion, such as demyelinating disease, neurodegenerative disease, brain tumors, skull base tumor, and inflammation.

14:30 4284.   Detection of Bone Metastases in Nasopharyngeal Carcinoma Patients: Accuracy of 3T Whole-body MRI and FDG-PET-CT 
Charng-Chyi Shieh1,2, Yu-Chun Lin1,2, Jiun-Jie Wang2,3, Yau-Yau Wai1,2, Chun-Huang Hsieh1, Sheng-Chieh Chan3,4, Tzu-Chen Yen3,4, and Shu-Hang Ng1,2
1Medical Imaging and Intervention, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan, 2Medical Imaging and Radiological Science, Chang Gung University, Taoyuan, Taiwan, 3Molecular Imaging Center, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan, 4Nuclear Medicine, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan

We prospectively compared the diagnostic capability of 3.0-Tesla whole-body (WB) MRI and FDG-PET-CT for bone metastasis in nasopharyngeal carcinoma (NPC). Twenty-four (6.2%) of our 388 NPC patients were diagnosed as having bone metastases. On a patient-based analysis, WB-MRI and FDG-PET-CT showed the similar sensitivity and specificity for bone metastasis (70.8 % vs 75.0 %, P=0.999; 99.5% vs 98.4%, P=0.289, respectively). Their diagnostic capabilities were equal (0.909 vs 0.909). We concluded that 3.0-Tesla WB-MRI is a feasible technique for the detection of bone metastasis in NPC patients, with similar sensitivity and equal diagnostic capacity to FDG-PET-CT.

15:00 4285.   "Flow-void Enhanced" Volumetric Black-blood Angiography Using 3D-TSE with Very Low-constant Refocusing Flip Angles and Sensitized Flow Compensation 
Masami Yoneyama1, Masnobu Nakamura1, Tomoyuki Okuaki1, Takashi Tabuchi1, Atsushi Takemura2, Makoto Obara2, and Junko Ogura1
1Medical Satellite Yaesu Clinic, Tokyo, Japan, 2Philips Electronics Japan, Tokyo, Japan

3D RARE (TSE) sequence is promising for black-blood angiography. In this study, we propose a new scheme of sequence parameter optimization for "flow-void enhanced" volumetric black-blood angiography. All experiments were performed on a 3.0T imager. Methods were flowing phantom study and volunteer study. From the results, optimal parameter for black-blood angiography was: very low refocusing flip angles, pseudo steady-state preparation chosen "90+alpha/2" preparation. Furthermore, "sensitized" flow-compensation at the "in-plane flow" imaging plane, that was more flow-voided in parallel direction of flow and phase-encode. This optimal sequence can be used for 3D volumetric black-blood angiography and vessel wall imaging.

Thursday May 12th
  13:30 - 15:30 Computer 107

13:30 4286.   Measuring the change in mechanical properties of upper airway soft tissues in obstructive sleep apnea using magnetic resonance elastography 
Elizabeth Nye1, Shaokoon Cheng1, Simon Gandevia2, David McKenzie3, Ralph Sinkus4, and Lynne Bilston2
1Neuroscience Research Australia, Sydney, NSW, Australia, 2Neuroscience Research Australia, Australia, 3University of New South Wales, Australia, 4Centre de Recherches Biomédicales Bichat-Beaujon, France

The pathophysiological mechanisms of obstructive sleep apnoea (OSA) are unclear and the change in mechanical properties of soft tissues and tongue muscles is likely to play an important role in the disorder. In this study, magnetic resonance elastography is used to probe the mechanical properties of the tongue and soft palate in five OSA patients and healthy normal subjects. Results shows that while the shear moduli of the tongue is significantly softer in the OSA patients (p < 0.05), the mechanical properties of the soft palate between the 2 subject groups are not significantly different (p > 0.05).

14:00 4287.   MRI of Head and Neck Cancer Patients for Radiotherapy Treatment Planning 
Scott Hanvey1, Martin Glegg2, and John Foster3
1Department of Clinical Physics and Bioengineering, Beatson West of Scotland Cancer Centre, Glasgow, Lanarkshire, United Kingdom, 2Beatson West of Scotland Cancer Centre, 3Glasgow Cardiac Magnetic Resonance Unit

In radiotherapy accurate localisation and definition of the planning target volume and its relationship to organs at risk is very important. For head and neck cancer patients MRI offers superior target delineation over CT. However, if the MRI scan is not acquired in the treatment position this can lead to a mismatch when registering with CT. The purpose of this study was to investigate 20 oropharynx cancer patients to determine whether it is necessary to immobilise patients for their MR radiotherapy planning scan or if a normal diagnostic MRI would suffice.

14:30 4288.   Echo-planar versus PROPELLER diffusion-weighted imaging at 3T for assessment of thyroid tumors 
Sidhartha Nagala1, Mary A McLean2, Daniel Scoffings3, Andrew N Priest3, Piyush Jani1, and John R Griffiths2
1Otolaryngology, Addenbrooke's Hospital, Cambridge, Cambridgeshire, United Kingdom, 2Cancer Research UK, Cambridge Research Institute, United Kingdom, 3Radiology, Addenbrooke's Hospital, Cambridge, United Kingdom

Diffusion weighted imaging has recently been used to differentiate between benign and malignant thyroid nodules. We compared the successfulness of EPI versus PROPELLER at 3T in the thyroid region. Images were evaluated by a consultant neuroradiologist on Functool software. We report visibly less distorted images using PROPELLER resulting in an increase in interpretable images. Our preliminary results show promise in differentiating between benign and malignant nodules. However, PROPELLER consistently produced higher ADC values than EPI. The cause of this is unclear and requires further investigation before PROPELLER can be recommended as the sequence of choice in this region.

15:00 4289.   Evaluation of the vocal tract with real time MRI in professional male altos 
Matthias Echternach1, Louisa Traser2, Bernhard Richter1, and Michael Markl3
1Institute of Musicians`Medicine, Freiburg University Medical Center, Freiburg, Germany, 2Charite, Berlin, Germany, 3Department of Radiology, Medical Physics, Freiburg University Medical Center, Freiburg, Germany

Aim of this study was to analyse vocal tract shapes in male alto register functions. Dynamic real time MRI of 8 frames per second was used to analyze the vocal tract profile in 7 professional male altos who sang on the vowel /a/ an ascending and descending scale from G3 to E4. The scale included their register transition from modal register falsetto. Register transitions from modal register to stage falsetto were associated with increased lip opening, jaw retraction, elevation and back positioning of the tongue, pharynx narrowing, uvula elevation, drop of larynx height and tilting of the larynx.

Electronic Posters : Neuroimaging
Click on to view the abstract pdf and click on to view the video presentation.
Spine/Spinal Cord

Monday May 9th
Exhibition Hall  14:00 - 16:00 Computer 108

14:00 4290.   Spinal cord 1H-MR spectroscopy in patients after brachial plexus root re-implantation 
Enrico De Vita1,2, Carolina Kachramanoglou1, Claudia AM Wheeler-Kingshott3, David L Thomas1, David Choi1, Alan Thompson1, and Olga Ciccarelli1
1Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, United Kingdom, 2Lysholm Department of Radiology, National Hospital for Neurology and Neurosurgery, London, United Kingdom, 3Department of Neuroinflammation, UCL Institute of Neurology, London, United Kingdom

We assessed whether 1H-MR spectroscopy of the spinal cord above the re-implanted brachial plexus roots is sensitive to pathological changes occurring in this region. A single-voxel caridac gated PRESS sequence with CHESS water suppression was obtained between C1 and C3 using a 3T scanner in patients who underwent re-implantation and healthy controls. Patients showed increased myo-Inositol/Creatine plus Phosphocreatine ratio when compared with healthy controls, suggesting reactive gliosis above the site of injury. Future studies will include patients with brachial plexus avulsion who did not undergo re-implantation, in order to understand whether this technique is sensitive to microscopic changes specific to re-implantation.

14:30 4291.   Diffusion Weighted Imaging of Spinal Tumors with Reduced Field of View EPI 
Samantha J Holdsworth1, Rafael O'Halloran1, Kristen Yeom1, Murat Aksoy1, Stefan Skare2, and Roland Bammer1
1Department of Radiology, Stanford University, Palo Alto, CA, United States, 2Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden

Diffusion-weighted (DW) and diffusion-tensor (DT) imaging has shown to be important for the assessment of spinal cord pathologies. Spinal cord DTI has been limited due to off-resonance effects that cause large geometric distortion in EPI. The zonally oblique multislice (ZOOM)-EPI technique is an approach which uses a tilted refocusing pulse to reduce the phase-encoding FOV, by which it accelerates phase-encode k-space traversal, thus reducing geometric distortion. Here we demonstrate the feasibility of ZOOM-EPI for assessing spinal tumors at 1.5T and 3T. To demonstrate the potential for further improvements in this technique, we also present distortion-corrected images acquired on a healthy volunteer at 3T.

15:00 4292.   4D flow characteristics of cerebrospinal fluid dynamics at the craniocervical junction and the cervical spinal canal in patients with Chiari malformation type I 
Alexander Christian Bunck1, Jan-Robert Kröger1, Alena Jüttner1, Angela Brentrup2, Barbara Fiedler3, Gerard R Crelier4, Wolfram Schwindt1, Walter Heindel1, Thomas Niederstadt1, and David Maintz1
1Department of Clinical Radiology, University Hospital of Münster, Münster, Germany, 2Department of Neurosurgery, University Hospital of Münster, Münster, Germany,3Department of Pediatrics, University Hospital of Münster, Münster, Germany, 4Institute for Biomedical Engineering, ETH and University of Zurich, Zurich, Switzerland

4D phase contrast imaging allows for a detailed analysis of alterations in cerebrospinal fluid dynamics in patients with Chiari malformation type I. Typical flow patterns are identified and related to symptoms and presence of concomitant syrinx.

15:30 4293.   Detection of spinal cord abnormality on Diffusion Tensor Imaging (DTI) in patients with unilateral deficit using pattern classification 
Arturo Cardenas-Blanco1, Santanu Chakraborty2, Fahad Alkherayf3, Eve Tsai3, Mark Schweitzer2, and Thanh Nguyen2
1Diagnostic Imaging Department, The Ottawa Hospital, Ottawa, Ontario, Canada, 2Radiology, The Ottawa Hospital, Ottawa, Ontario, Canada, 3Neurosurgery, The Ottawa Hospital, Ottawa, Ontario

Conventional magnetic resonance imaging in the spinal Cord (SC) is often insufficient to diagnose, asses the stage and progression of disease. Abnormalities seen on conventional MRI are often unreleated to clinical findings. During the last years, Diffusion Tensor Imaging (DTI) has become the preferred tool to analyze white matter properties, fibre organization and mobility of the water molecules, reflected by Fractional Anisotropy (FA) and Mean Diffusivity (MD) respectively. To reduce the discrepancies between MR findings and clinical presentations we introduce a new model to analyze spinal cord images based on pattern classification. Looking at the interrelationship of quantitative MR parameters in healthy spinal cord, a pattern classification algorithm was trained in healhty subjects and tested in patients with unilateral deficits.

Tuesday May 10th
  13:30 - 15:30 Computer 108

13:30 4294.   Detection of Nerve Injury with Diffusion Weighted Wide Band Steady State Free Precession (DW-WBSSFP) in the Lumbar Spine 
Giovanna Danagoulian1, Rivka R Colen2, Krishna Nayak3, Srinivasan Mukundan2, Ferenc Jolesz2, and Ehud J Schmidt2
1Brigham and Women's Hospital, Boston, MA, United States, 2Brigham and Women's Hospital, 3University of Southern California

3D High-resolution Wide-band Steady State Free Precession (WBSSFP), a variant of SSFP with alternating short and long repetition times (TRs) that allows for high-resolution spine imaging, a result of reduced susceptibility artifacts, was further modified to include diffusion gradients in its short-TR period. The new sequence, Diffusion-weighted WBSSFP (DW-WBSSFP) was applied to detecting nerve injury, based on changes in diffusion, in the extra-dural spine. In a cohort of patients with degenerative spine diseases, DW-WBSSP detected large change in diffusion not seen in normals.

Paola Valsasina1, Maria Assunta Rocca1, Stefania Sala1, Mark Andrew Horsfield2, Patrick Stroman3, Martina Absinta1, Giancarlo Comi4, and Massimo Filippi1
1Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Hospital, Milan, Milan, Italy, 2Department of Cardiovascular Sciences, University of Leicester, Leicester, Leicester, United Kingdom, 3Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada, 4Department of Neurology, San Raffaele Hospital, Milan, Milan, Italy

Aim of this study was to apply a recently developed semi-automated method for cord normalization to high-resolution 3D T1-weighted images, in order to perform coregistration of cervical cord images in a common standard space and voxel-based analysis of cord atrophy. Images were acquired from 41 healthy controls and 31 patients with relapsing-remitting multiple sclerosis (MS). For each subject, normalization process was successfully run and cord masks were created with a semi-automatic approach based on active surface. Statistical analysis of these masks allowed the creation of cervical cord probability maps and voxel-wise comparison of cord volume between controls and MS patients.

14:30 4296.   Peripheral Nerve Imaging with 3D Gradient Recalled Echo-Selective Species Imaging Sequence at 3.0T: A Preliminary Study 
Hao Shen1, Guang Cao2, Xin Lou3, Ailian Zhang3, Jinfeng Li3, Zhikui Xiao1, Qian Jiang4, and Anthony T Vu5
1Global Applied Science Laboratory, GE Healthcare, Beijing, Beijing, China, People's Republic of, 2Global Applied Science Laboratory, GE Healthcare, Hong Kong, China, People's Republic of, 3Department of Radiology, Chinese PLA General Hospital, Beijing, Beijing, China, People's Republic of, 4MR Modality, GE Healthcare, Shanghai, Shanghai, China, People's Republic of, 5MR PSD/Applications Engineering, GE Healthcare, Waukesha, Wisconsin, United States

Magnetic resonance nerve imaging is playing an important role in evaluating some diseases of nerves and nerve bundles. In this study, we applied a three-dimensional Gradient Recalled Echo ¨C Selective Species Imaging (GRE-SSI) sequence to image the peripheral nerve on a 3.0T scanner.

15:00 4297.   Pain or no pain: Paradigm to image lower back pain with fMRI 
Harish A Sharma1, Raj Gupta2, and William Olivero3
1Department of Medical Biophysics, University of Western Ontario, London, ON, Canada, 2Medicine, University of Illinois, 3Neurosurgery, Carle Foundation Hospital

Low back pain affects millions of patients. fMRI studies have made significant contributions to the understanding of how the brain processes pain. However, most of the studies have involved normal subjects subjected to painful stimuli during fMRI. Studying patients with acute pain has been difficult because of motion artifact and the difficulty in altering the patients painful experience during fMRI. We elected to study patients with back pain and radiculopathy from a herniated disc using various maneuvers like leg raise, dorsiflexion of the foot and tensing of the muscles of thigh in an attempt to alter the pain perception to determine if we could reliably obtain fMRI images when the patients pain scale rating changed during the maneuvers.

Wednesday May 11th
  13:30 - 15:30 Computer 108

13:30 4298.   Magnetic resonance spectroscopy of human cervical spondylosis at 3T 
Rajakumar Nagarajan1, Michael Albert Thomas1, Benjamin M Ellingson1, Langston Holly2, and Noriko Salamon1
1Radiological Sciences, University of California Los Angeles, Los Angeles, California, United States, 2Neurosurgery, University of California Los Angeles

Cervical spondylosis is a general term for age-related wear and tear affecting the joints in the neck. Proton (1H) magnetic resonance spectroscopy (MRS) has been widely used over the last few years to differentiate metabolic changes associated with neurological disease in the brain. This present study attempts to quantitate metabolites in cervical spine using point resolved spectroscopy (PRESS) on a 3T MRI scanner processed by the LC model software. Our preliminary results show significantly increased total choline, and increasing trend of lactate (Lac) and decreasing trend of N-acetylaspartate (NAA) in the spondylosis patient group.

14:00 4299.   Evidence of Wallerian degeneration in the human spinal cord using in vivo high-resolution DTI and magnetization transfer 
Julien Cohen-Adad1,2, Bradley Buchbinder2,3, Lawrence L Wald1,4, and Anne Louise Oaklander2,3
1A.A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States, 2Harvard Medical School, Boston, MA, United States, 3Massachusetts General Hospital, Boston, MA, United States, 4Harvard-MIT Division of Health Sciences and Technology, MIT, Cambridge, MA, United States

We combined high resolution diffusion-weighted, magnetization transfer and conventional MRI of the spinal cord in a patient with focal cervical cord injury (SCI). Concomitant analysis of images suggested anterograde Wallerian degeneration in the dorsal left pathway. The correlation between DW and MT measurements and the neurological abnormalities provides incentive to perform multi-parametric spinal MRI to better distinguish demyelination and degeneration after SCI.

14:30 4300.   Understanding the fMRI response to thermal stimuli in the human spinal cord 
Christopher Alan Kidd1, Rachael Lee Bosma1, and Patrick W. Stroman1,2
1Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada, 2Departments of Diagnostic Radiology and Physics, Queen's University, Kingston, Ontario, Canada

Spinal fMRI is a means of assessing changes of neuronal function after spinal cord injury. To use spinal fMRI as a clinical tool, healthy spinal cord responses must first be characterized. Using a HASTE sequence, fMRI protocols were carried out in healthy individuals by applying thermal stimulation to four disparate dermatomes activating cervical, upper and lower thoracic, and lumbar segments of the spinal cord. Our findings show that similar signal responses occur within the cervical and lumbar segments, and contrasting activity patterns in thoracic segments. Furthermore, all levels of the cord show neuronal activation corresponding to a change in temperature.

15:00 4301.   MRI Monitoring of Neural Precursor Cell Transplantation Therapy in a Rat Spinal Cord Injury Model 
Rafal Janik1, Greg Hawryluk2,3, Kimberly Lara Desmond4, Ryan Fobel4, Micheal Fehlings2,3, and Greg J Stanisz1,4
1Imaging Research, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada, 2Division of Neurosurgery, University of Toronto, Toronto, Ontario, Canada, 3Krembil Neuroscience Centre, Toronto Western Research Institute, Toronto, Ontario, Canada, 4Department of Biophysics, University of Toronto, Toronto, Ontario, Canada

7T quantitative MR measurements (DTI, QT2, T1, and MT) of rats with spinal cord injuries were performed to monitor the efficacy of neural precursor cell (NPC) transplantation therapy. The parameter maps from all of the scans were used to automatically segment healthy neural tissue from lesional tissue and CSF. Total neural tissue measured by MR and histology was higher in NPC transplanted animals. T1 relaxation rates were lower in NPC transplanted animals suggesting reduced inflammation and CSF infiltration. In vivo MR measures of tissue preservation showed a statistically significant correlation (p<0.05) of 0.63 with histology.

Thursday May 12th
  13:30 - 15:30 Computer 108

13:30 4302.   BLADE in sagittal T2-weighted imaging of the cervical spine: value for spinal cord lesions 
Claudia Fellner1, Cynthia Menzel1,2, Christian Stroszczynski1, and Thomas Finkenzeller1,3
1Institute of Radiology, University Medical Center Regensburg, Regensburg, Germany, 2Institute of Radiology and Neuroradiology, Krankenhaus Barmherzige Brüder, Regensburg, Germany, 3Institute of Diagnostic and Interventional Radiology, Klinikum Weiden, Weiden, Germany

To evaluate the BLADE technique for sagittal T2-weighted imaging of the cervical spine for the diagnosis of spinal cord lesions, BLADE and TSE sequences were compared in 25 patients with 37 spinal cord lesions. Visual evaluation was done by 2 independent readers. BLADE was statistically superior (P<0.05) to TSE regarding image sharpness and delineation of the dura; the diagnostic reliability for the depiction of the spinal cord was also better with BLADE (P=0.056). Contrast of spinal cord lesions was very similar using BLADE and TSE. Therefore, BLADE can be used for routine sagittal T2-weighted imaging of the cervical spine.

14:00 4303.   Improved T1 Weighted Dynamic Contrast Enhanced MRI to Probe Microvascularity and Assessment of Spine Bone Marrow 
Mohan Pauliah1, Kyung K Peck1,2, Yoshiya Josh Yamada3, Eric Lis1,4, Michelle S Bradbury1,5, and Sasan Karimi1
1Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, United States, 2Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, United States, 3Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York, United States, 4Interventional Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, United States, 5Molecular Imaging, Memorial Sloan Kettering Cancer Center, New York, New York, United States

Noninvasive characterization of the vascular microenvironment has not been fully investigated in bone marrow diseases. Current clinical evaluations and prognosis based on conventional MRI are markedly limited. Measuring the changes in tumor hemodynamics would give insight into tumor heterogeneity. We aimed to develop an imaging biomarker to facilitate the decision-making process and establish a robust technique to unravel the complexity of tumor vasculature that may aid in therapeutic management by employing the improved T1 weighted DCE MR algorithm. We propose a non-invasive technique to improve the accuracy of perfusion metrics of bone marrow and enable visual appreciation that characterize marrow heterogeneity and differentiate between different conditions that affect the marrow pathophysiologically.

14:30 4304.   Diffusion Tensor Imaging Characteristics of Normal Human Cervical Spinal Cord at 3T 
Khin Khin Tha1, Satoshi Terae2, Kinya Ishizaka2, Tomoyuki Okuaki3, Makoto Hirotani4, Kentaro Kobayashi2, Marc van Cauteren5, and Hiroki Shirato1
1Dept. of Radiobiology and Medical Engineering, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan, 2Dept. of Radiology, Hokkaido University Hospital, 3Medical Satellite Yaesu Clinic, 4Dept. of Neurology, Hokkaido University Graduate School of Medicine, 5Philips Healthcare Asia Pacific

rFOV-DTI was performed to cervical spinal cord of 43 normal healthy subjects. DTI characteristics varied with anatomical location, gender, and age. Laterality was also observed. Normative values are necessary in evaluation of diseases of spinal cord.

15:00 4305.   Diffusion tensor imaging changes in the spinal cord of amyotrophic lateral sclerosis patients 
Wim Van Hecke1, Louise Emsell2, Caroline Sage3, Stefan Sunaert3, and Paul M Parizel4
1University of Antwerp, Antwerp, Antwerp, Belgium, 2The Murdoch Childrens Research Institute, Australia, 3University of Leuven, Belgium, 4University of Antwerp, Belgium

Diffusion tensor tractography was used to delineate the spinal cord in patients with amyotrphic lateral sclerosis (ALS) and healthy control subjects. The FA of the ALS patients was significantly lower than in the control subjects, especially in levels C3-C5.

Electronic Posters : Neuroimaging
Click on to view the abstract pdf and click on to view the video presentation.
Developing Brain I

Monday May 9th
Exhibition Hall  14:00 - 16:00 Computer 109

14:00 4306.   Infant 0-1-2 Brain Atlases for MRI Segmentation and Normalization 
Feng Shi1, Guorong Wu1, Pew-Thian Yap1, Hongjun Jia1, John H. Gilmore2, Weili Lin1, and Dinggang Shen1
1Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 2Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States

Direct applying adult or even pediatric atlases may compromise accuracy in analyzing infant brain images. In this abstract, we introduce a set of brain atlases which are dedicated for neonates, 1-year-olds, and 2-year-olds. Each atlas comprises a set of 3D images made up of the intensity model, tissue probability maps, and anatomical parcellation map. These components are constructed with the help of state-of-the-art infant MR segmentation and groupwise registration methods, applied on a set of infant images which are longitudinally acquired from 95 healthy infants. These atlases are publicly available on our website, http://bric.unc.edu/ideagroup/free-softwares/.

14:30 4307.   Longitudinal DTI in Young Children with Prenatal Methamphetamine Exposure: A 3 Year Follow-Up Study 
Linda Chang1, Kazim Gumus1, Ashley Saito1, Aaron Hoo1, Alexandra Pritchett1, Daniel Alicata1, Christine Cloak1, and Thomas Ernst1
1Department of Medicine, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, Hawaii, United States

Methamphetamine is a neurotoxic drug but its effects on brain development has not been well studied. 118 children were enrolled at ages 3-4 years (50 METH-exposed prenatally, 68 un-exposed controls); DTI was performed annually over 3 years. An automated-atlas approach with LDDMM in MRIStudio was used for data analyses. Despite similar physical characteristics (including head circumference), global cognitive function (on Stanford-Binet), and parental education, intelligence and mood, METH-exposed children had lower mean diffusion throughout and abnormal fractional anisotropy compared to un-exposed controls. These diffusion abnormalities persisted over the 3-year follow-up period. Further correlations will be performed with cognitive measurements.

15:00 4308.   Age associated changes in subcortical structures in preadolescent children 
L. Tugan Muftuler1, Angela T Cheriyan2, Kevin M Head3, Min-Ying Su1, Claudia Buss3, Curt A Sandman3, and Elysia P Davis3
1Center for Functional Onco-imaging, University of California, Irvine, CA, United States, 2Biological Sciences, University of California, Irvine, CA, 3Psychiatry and Human Behavior, University of California, Orange, CA

There is evidence that abnormal brain development during childhood is a risk factor for various cognitive and psychiatric disorders. Although cortical development from childhood until early adulthood has been studied by several groups, there is very limited normative data available on subcortical structures of typically developing children, especially within the narrow preadolescent age range. We analyzed high resolution MRI images from 103 normally developing preadolescent children to study age associated differences in major subcortical structures. We found that the major age-associated changes were seen in the medial dorsal thalamus between ages 6 and 10.

15:30 4309.   Feasibility of non-invasive quantitative MRI measurements of cerebral vascular reactivity using a computer controlled stimulus in children with sickle cell disease 
Andrea Kassner1,2, Jackie Leung2, Fatima Nathoo3, Stephanie Dorner4, Joseph A Fisher5, Manohar Shroff2, Gabrielle de Veber6, and Suzan Williams7
1Medical Imaging, University of Toronto, Toronto, Ontario, Canada, 2Diagnostic Imaging, The Hospital for Sick Children, Toronto, Ontario, Canada, 3Respiratory therapy, The Hospital for Sick Children, Toronto, Ontario, Canada, 4Thornhill Research Inc., Toronto, Ontario, Canada, 5Physiology, University of Toronto, Toronto, Ontario, Canada, 6Neurology, Hospital for Sick Children, Toronto, Ontario, Canada, 7Hematology, Hospital for Sick Children, Toronto, Ontario, Canada

Sickle cell disease (SCD) is the major cause of stroke in children leading to mortality or long-term disability. A noninvasive means of measuring cerebral blood flow (CBF) reserve would facilitate assessment and clinical management of these patients. BOLD MRI has been used as a surrogate for CBF changes in response to a vasoactive stimulus such as partial pressure of CO2 (PCO2). However, within the pediatric population, CVR studies are not common. We imaged 11 SCD patients using a system able to target end-tidal PCO2 in synchrony with BOLD MRI, and found a strong concordance between CVR and angiographic findings.

Tuesday May 10th
  13:30 - 15:30 Computer 109

13:30 4310.   Neurogenetics in the Pediatric Brain: A 1H MRS Study of Brain Development 
Jack Knight-Scott1, and Sarah Andrea Wijtenburg1
1Radiology, CHOA, Atlanta, Georgia, United States

Understanding normal brain development is essential to all basic and clinical research on pediatric brain disorders. In this work, we examine neurochemistry in the pediatric brain using STEAM at 3-T. In general, we detect higher neurogenetic activity in the pediatric brain, with nine metabolites showing significant differences from the adult brain. Relative to the adult brain, phosphorylethanolamine and GABA showed the largest increase; however, the most striking difference was the elevation of the 1.63-ppm M4 macrocmolecule resonance in the adult brain.

14:00 4311.   Identifying growth velocity discontinuities in the first postnatal year brain development with diffusion tensor imaging 
Yasheng Chen1, Hongtu Zhu2, Jiaping Wang2, Hongyu An1, Dinggang Shen1, and Weili Lin1
1Radiology, Univ. of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 2Biostatistics, Univ. of North Carolina at Chapel Hill, Chapel Hill, NC, United States

With 105 longitudinal DTI datasets acquired from 35 healthy full-term infants, we have demonstrated that almost all brain regions (excluding corpus callosum splenium) demonstrating a significant change in growth velocities after 100 days during the first postnatal year for DTI parameters including FA and MD. These results agree with previous postmortem histological findings that a more rapid myelination occurs within the 43~54 post conceptual weeks. Thus, it is very promising to correlate the growth trajectories of DTI parameters with the development of early postnatal white matter myelination.

14:30 4312.   Development of axonal pathways in preadolescent children 
L. Tugan Muftuler1, Anna Wiebel2, Sandra Waeldin2, Min-Ying Su1, Claudia Buss3, Curt A Sandman3, and Elysia P Davis3
1Center for Functional Onco-imaging, University of California, Irvine, CA, United States, 2University of Trier, Germany, 3Psychiatry and Human Behavior, University of California, Orange, CA

Abnormal brain development during childhood increases the risks for various cognitive and psychiatric disorders. Therefore understanding normal brain development is important to study these abnormalities. We studied age-associated changes in major pathways of the cerebral white matter in children using high resolution DTI. We focused our study on a narrow age range during late childhood, which is a critical phase in cognitive development. Furthermore, we conducted whole brain analysis to study changes in FA and MD along all major fiber tracts. Our findings illustrate changes in fiber pathways of the brain at a higher detail than previously reported.

15:00 4313.   Temporal evolution of brain metabolic substrates differs among major anatomical lobes during the first months of life in human 
Yang Yang1, Hongyu An2, Feng Shi2, Wei Gao2, Dinggang Shen2, and Weili Lin2
1Department of Biomedical Engineering and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 2Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States

In this study, a 3D 1H-MRS method was employed to investigate early brain metabolic maturation in the first months of life in human. We found that development of neuronal functions largely occurs during the first 3 months of life, followed by a plateau from 3 to 6 months. We also found that rather stable NAA/Cr ratio in the occipital lobe may suggest that a large part of metabolic substrate of visual function may have already completed by the time of birth.

Wednesday May 11th
  13:30 - 15:30 Computer 109

13:30 4314.   Elastic Registration Based Neonatal Brain Segmentation 
Petronella Anbeek1, Britt J.M. van Kooij1, Floris Groenendaal1, Linda S. de Vries1, and Manon J.N.L. Benders1
1Neonatology, Wilhelmina Children's Hospital, Utrecht, Netherlands

A powerful fully automatic technique for neonatal brain segmentation is proposed, based on elastic registration combined with K-nearest neighbor classification. The method uses two routine diagnostic MR images: 3D-T1- and T2-weighted, and segments 8 brain structures simultaneously: (un)myelinated white matter, cortical gray matter, basal ganglia, cerebro-spinal fluid, ventricles, brainstem and cerebellum. Results are evaluated by comparison with a gold standard, showing high Dice similarity indexes (0.80-0.92) for 7 tissues. This technique is suitable for large and longitudinal neonatal brain analysis studies.

14:00 4315.   Absolute brain metabolite concentrations in non-acute Maple Syrup Urine Disease 
Emilie Ruth Muelly1, Don C. Bigler1, Kevin A. Strauss2, Pavlina Todorova3, D. Holmes Morton2, Julie Mack4, Arabinda Choudhary4, David O. Aleman1, Jeff Vesek4, Megan Taylor Sutton1, Scott C. Bunce1, and Gregory J. Moore5
1Center for Emerging Neurotechnology & Imaging, Penn State Hershey Neurosciences Institute, Penn State College of Medicine, Hershey, PA, United States, 2Clinic for Special Children, Strasburg, PA, 3Division of Basic Sciences, University of Texas Southwestern Medical Center, Dallas, TX, 4Radiology, Penn State College of Medicine, Hershey, PA, United States, 5Radiology, Geisinger Medical Center, Danville, PA

Maple Syrup Urine Disease (MSUD) is an inborn error of metabolism of branched-chain amino acids. Illness and stress puts MSUD patients at risk of acute crises and encephalopathy despite adequate dietary treatment. Chronically, neuropsychiatric sequelae such as depression, anxiety may develop. The effects of MSUD on neurochemistry in the chronic state is unknown. We conducted single voxel proton magnetic resonance spectroscopy in three brain regions in MSUD patients and their unaffected siblings. MSUD patients exhibited decreased N-acetylaspartate, creatine, and glutamate. These findings suggest impaired energy production and neurotransmitter depletion, two theories of pathogenesis of neuropsychiatric sequelae in MSUD.

14:30 4316.   Longitudinal guided level-sets for consistent neonatal image segmentation 
Li Wang1, Feng Shi1, John H Gilmore2, Weili Lin3, and Dinggang Shen1
1IDEA Lab, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 2Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 3MRI Lab, Department of Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States

Accurate segmentation of neonatal brain MR images in longitudinal MRI studies plays an important role in revealing neurodevelopmental disorders. Due to poor image quality, it still remains challenging to segment neonatal brain images. Most existing methods are voxel-based and work on only the single time-point image, and thus cannot benefit from the tissue distribution information which can be provided by the late-time-point images. In this paper, we propose a novel longitudinal guided level-sets method for consistent neonatal image segmentation, by combining intensity information, atlas prior, cortical thickness, and longitudinal information into a variational framework.

15:00 4317.   Sharp curvature in frontal lobe white matter pathways of children with autism spectrum disorder 
Jeong-Won Jeong1,2, Ajay Kumar1,2, Senthil K. Sundaram1,2, Harry T. Chigani1,2, and Diane C. Chugani2,3
1Pediatrics, Neurology, Wayne State University, Detroit, Michigan, United States, 2PET center, Children's Hospital of Michigan, Detroit, Michigan, United States, 3Radiology, Wayne State University, Detroit

The purpose of this study was to examine the curvature of frontal lobe tracts in ASD children using an objective tract based morphometry analysis and investigate the curvature-specific changes in diffusion parameters of these tracts. Significantly higher curvatures were found in children with ASD, especially at the parieto-temporal junction for arcuate fasciculus, at the fronto-temporal junction for uncinate fasciculus, and at the midline of the corpus callosum in genu. In addition, the children with ASD showed higher radial diffusivity at the bending regions of arcuate fasciculus, uncinate fasciculus, ang corpus callosum in genu, respectively.

Thursday May 12th
  13:30 - 15:30 Computer 109

13:30 4318.   Impairment of the medullary veins on neonatal subependymal hemorrhage using susceptibility-weighted imaging 
Tetsu Niwa1, Noriko Aida1, Yasuhiko Tachibana1, Reiko Watanabe1, Tetsuhiko Okabe1,2, and Jun Shibasaki3
1Radiology, Kanagawa Children's Medical Center, Yokohama, Kanagawa, Japan, 2Radiology, Yokohama City University, Yokohama, Japan, 3Neonatology, Kanagawa Children's Medical Center

Subependymal hemorrhage (SEH) occurs with a hypoxic-ischemic injury especially in preterm infants. We assessed the visualization of the branches of the deep veins in infants with SEH according to SEH grade. We found more frequently impaired branches of the medullary veins in infants with SEH-Grade IV. On the contrary, SEH with lower grade showed less frequent relation to the impairment of the medullary veins. SEH with parenchymal hemorrhage may be accompanied with more frequent impairment of the branches of the medullary veins.

14:00 4319.   3-Tesla Cerebral Proton Magnetic Resonance Spectroscopy in Healthy Term and Extremely Preterm Infants 
Yuxiang Zhou1, Nehal A. Parikh2, Katrina Burson2, and Ponnada A Narayana1
1Diagnostic & Interventional Imaging, University of Texas Health Science Center at Houston, Houston, Texas, United States, 2Dept. of Pediatrics, University of Texas Health Science Center at Houston, Houston, Texas, United States

Cerebral proton MR spectroscopy was performed on 65 very preterm and 12 healthy term neonates, which offers a wealth of data on tissue biochemistry in various brain regions. Significant variations in the metabolite levels have been observed in the neonatal brains at different locations and between term and preterm neonates. These metabolites can represent potential biomarkers of the underlying pathology in extremely preterm neonates. Our ongoing work, correlating metabolites with neonatal risk factors and NDI, will further determine the value of MRS cerebral metabolites as biomarkers of brain development/injury in extremely preterm infants.

14:30 4320.   Longitudinal Analysis of Tissue Property Changes in Multi-modal MRI of the Developing Preterm Brain 
Ahmed Serag1, Paul Aljabar1, Gareth Ball2, Serena J Counsell2, James P Boardman2,3, Daniel Rueckert1, and Jo V Hajnal2
1Department of Computing, Imperial College London, London, United Kingdom, 2Imaging Sciences Department, MRC Institute of Clinical Sciences, Imperial College London, London, United Kingdom, 3Simpson Centre for Reproductive Health, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom

Preterm birth is associated with abnormal brain development and long-term neurodevelopmental impairment. Quantitative magnetic resonance (MR) studies of preterm brain injury have focused on morphological features such as shape and volume and on measures of tissue microstructure obtained from diffusion tensor imaging. In this work, we focus on longitudinal changes in signal intensity, which can offer a useful marker for mapping developmental changes. The study shows that signal change analysis on a large cohort is feasible, and it can serve as a marker for developmental brain changes, both normal and abnormal, which might ultimately lead to a better understanding of the trajectory of early brain maturation.

15:00 4321.   Automated Partial Volume Tissue Classification in Preterm Neonates 
Dallas Card1, Revital Nossin-Manor1,2, and John G Sled3,4
1Diagnostic Imaging, The Hospital for Sick Children, Toronto, Ontario, Canada, 2Neurosciences & Mental Health, Research Institute, The Hospital for Sick Children, Toronto, Ontaro, Canada, 3Physiology & Experimental Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada, 4Medical Biophysics, The University of Toronto, Toronto, Ontario, Canada

Automated tissue classification in very preterm neonates presents unique challenges which commonly result in the misclassification of partial volume voxels. This abstract presents an alternative approach to this problem, based on the trimmed minimum covariance determinant method. This algorithm was used to segment the brains of 44 very preterm neonates into white matter, grey matter, cerebral spinal fluid, and two partial volume classes. Our results show clear differentiation between classes with the partial volume voxels correctly labeled in most cases. An inter-rater comparison involving 12 subjects confirmed its reliability, with all mean Dice coefficients greater than 0.8.

Electronic Posters : Neuroimaging
Click on to view the abstract pdf and click on to view the video presentation.
Developing Brain II

Monday May 9th
Exhibition Hall  14:00 - 16:00 Computer 110

14:00 4322.   Assessment of the maturation of the optic radiation in children and adolescents with probabilistic tractography 
Michael Dayan1, Monica Munoz2,3, Sebastian Jentschke2,4, Martin J Chadwick2,5, Janine Cooper2, Kate Riney6, Faraneh Vargha-Khadem2, and Chris Alan Clark1
1Imaging & Biophysics, UCL Institute of Child Health, London, United Kingdom, 2Developmental Cognitive Neuroscience Unit, UCL Institute of Child Health, London, United Kingdom, 3School of Medicine, University of Castilla–La Mancha, Albacete, Spain, 4Free University, Cluster of Excellence "Languages of Emotion", Berlin, Germany,5Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, London, United Kingdom, 6Neurosciences Unit, UCL Institute of Child Health, London, United Kingdom

The optic radiation is a white matter structure part of the visual pathway known to be myelin mature by the age of 3 years old. This study based on a cohort of 70 children assessed if any age related change and any effect of gender and hemisphere could be found through multiple regression analysis applied to the diffusion tensor imaging (DTI) parameters (FA, lower case Greek lambda||, lower case Greek lambda¬) computed within tracts reconstructed from probabilistic tractography. For lower case Greek lambda|| and lower case Greek lambda¬ a significant dependence on hemisphere was demonstrated. An age effect was shown for lower case Greek lambda|| in males left hemisphere (p < 0.008) and for lower case Greek lambda¬ for both hemisphere in males (p<0.01) but only in the right hemisphere for females (p < 0.01). Strong evidence for an age effect was also found for FA (p=0.00001). This work suggests that changes in the optic radiation are occurring up to adulthood and are varying according to hemisphere and gender.

14:30 4323.   Time Course of Diffusion Restriction in Neonates with Hypoxic Ischemic Encephalopathy Treated with Hypothermia 
Nathalie Bednarek1, Jared Wilkinson1, Amit Mathur1, Preethi Srinivasakumar1, Jeff Neil1, Terrie Inder1, and Joshua Shimony1
1Washington University School of Medicine, St. Louis, MO, United States

Hypoxic ischemic encephalopathy (HIE) in infants is often treated with hypothermia during the early days of life. Knowledge of the time course of diffusion changes after ischemia is critical for accurate radiologic interpretation and deciding the optimal time to order the MRI. This study demonstrates that the time course of diffusion changes in infants with HIE treated with hypothermia is different from those not treated with hypothermia.

Salil Soman1, Samantha J Holdsworth2, Patrick David Barnes1, Roland Bammer2, and Kristen Yeom1
1Department of Radiology, Stanford University, Stanford, California, United States, 2Department of Radiology, Lucas Center, Stanford University, Stanford, California, United States

Susceptibility Weighted imaging (SWI) utilizes 3D gradient echo (GRE) acquisition post-processing to accentuate blood products, but takes up to 10 minutes, (compared to the 2-3 minutes for conventional 2D GRE ), limiting its utility. We performed SWI post processing on 50 conventional 2D GRE studies and found more than half demonstrated either additional or more conspicuous findings. We also found the SWI phase unwrapped image could help distinguish hemorrhage from calcification. COnventional 2D GRE findings such as venous thromboses were less distinctive on SWI processed images due to increased conspicuity of thrombosed and non thrombosed venous structures. Overall, we found the SWI post processed technique of 2D GRE sequences enhanced clinical utility.

15:30 4325.   Grey and White Matter Differences in 1H-MRS Metabolic Ratios in the Preterm Brain 
Dallas Card1, John G Sled2,3, Aideen M Moore4,5, Hilary E Whyte4,5, and Margot J Taylor1,6
1Diagnostic Imaging, The Hospital for Sick Children, Toronto, Ontario, Canada, 2Physiology & Experimental Medicine, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada, 3Medical Biophysics, The University of Toronto, Toronto, Ontario, Canada, 4Neonatology, The Hospital for Sick Children, Toronto, Ontario, Canada, 5Paediatrics, The University of Toronto, Toronto, Ontario, Canada, 6Medical Imaging, The University of Toronto, Toronto, Ontario, Canada

Magnetic Resonance Spectroscopic Imaging (MRSI) provides a metabolic snapshot of the brain, and therefore has the potential to provide important insight into preterm brain development. We have combined a short MRSI scan with a fully-automated spectroscopy analysis pipeline and tissue classification to provide estimates of metabolite ratios in 55 very preterm neonates scanned within two weeks of birth. A one-way ANOVA demonstrated a significant difference between white matter and grey matter for both N-Acetylaspartate (NAA) / Choline and NAA / Creatine. In addition, NAA/Choline significant increased with age in grey matter over the preterm period.

Tuesday May 10th
  13:30 - 15:30 Computer 110

13:30 4326.   Feasibility of functional resting-state measurements of the fetal brain 
Veronika Schöpf1,2, Gregor Kasprian1, Christian M Mitter1, Peter C Brugger3, and Daniela Prayer1
1Department of Radiology, Division of Neuroradiology, Medical University Vienna, Vienna, Vienna, Austria, 2MR Centre of Excellence, Medical University Vienna, Vienna, Vienna, Austria, 3Center of Anatomy and Cell Biology, Integrative Morphology Group, Medical University Vienna, Vienna, Vienna, Austria

FMRI has already been used to study fetal brain activity in utero using different kind of stimulation methods. The underlying neuronal mechanisms strongly connected to gestational weeks of these activity networks have not been described yet. In this study we used functional connectivity analyses allowing the characterization of interregional neural interactions during spontaneous activity during rest to study those underlying mechanisms, aiming at specifying the differences of functionally connected cortical networks over fetal brain development stages.

14:00 4327.   DTI based tractography of fetal periventricular crossroad regions in utero 
Christian Mitter1, Gregor Kasprian1, Peter Christian Brugger2, Laura Perju-Dumbrava3, Ivica Kostovic4, and Daniela Prayer1
1Department of Radiology, Division of Neuroradiology, Medical University of Vienna, Vienna, Austria, 2Center of Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria, 3Institute of Neurology, Medical University of Vienna, Vienna, Austria, 4Croatian Institute for Brain Research, University of Zagreb School of Medicine, Zagreb, Croatia

Various fetal brain abnormalities are associated with MR signal alterations of periventricular crossroad regions. We used DTI and tractography to segment and characterize individual white matter fiber tracts within periventricular crossroad regions in living unsedated fetuses in utero between gestational week 20 and 34. 7 Fetuses underwent 1.5 Tesla MR imaging during routine clinical fetal MR examinations. DTI postprocessing with tractography was performed by using a multiple ROI approach. By using tractography we were able to segment the posterior periventricular crossroad region into sagitally oriented strata of thalamocortical, corticopontine, external capsule and association fibers.

14:30 4328.   Atlas-based T2 Relaxometry of the Developing Child Brain: Serial and Cross-sectional Analysis 
Khader M Hasan1, Indika S Walimuni1, Larry A Kramer1, and Linda Ewing-Cobbs2
1Radiology, UTHSCH, Houston, Texas, United States, 2Pediatrics, UTHSCH, Houston, Texas, United States

Compared to contradictory and amble volumetric reports on the developing child brain, there has been no comprehensive account of the application of brain atlas-based methods to map the regional tissue relaxation. In this work, we present for the first time a T2 relaxation vs. age atlas of the developing child brain. We have also compared the relaxation times between the right and left hemispheres. Given several previous reports on the accumulation of non-heme iron in deep subcortical and cortical gray matter (GM) structures as reflected by the decrease in T2 relaxation time, we also hypothesized that serial monitoring of the deep gray mater T2 relaxation time would offer a reliable means to assess sensitivity of for serial changes. We demonstrate weak gender effects, regional hetrogeniety, laterality, age-dependence and the sensitivity of the T2 relaxation time and utility in following development-related changes.

15:00 4329.   Simultaneous High Resolution Ex-vivo Diffusion Imaging of White Matter and Muscles 
Thomas Benner1, Allison Stevens1, Michelle Roy1, and Bruce Fischl1
1Radiology, Athinoula A. Martinos Center, Charlestown, MA, United States

A fetal ex-vivo brain was imaged using diffusion-weighted steady state free procession (DW-SSFP) imaging for simultaneous fiber tracking of white matter and muscle tissue. The sample was scanned for 56 hours at 7 T at a spatial resolution of 0.4x0.4x0.4 mm3 isotropic using a custom solenoid coil. White matter fiber tracking worked well and facial, neck, and extraocular muscles were clearly visible.

Wednesday May 11th
  13:30 - 15:30 Computer 110

13:30 4330.   Relationship between the arcuate fasciculus and cortical structure in pediatric patients with polymicrogyria: a pilot study. 
Michael John Paldino1, Rudolph Pienaar2, Annapurna Poduri3, Katyucia Macedo Rodrigues1, and Patricia Ellen Grant1
1Radiology, Children's Hospital Boston, Boston, MA, United States, 2Newborn Medicine, Children's Hospital Boston, Boston, MA, United States, 3Neurology, Children's Hospital Boston, Boston, MA, United States

Polymicrogyria consists of abnormal cortical lamination, with most severe involvement of layer 5. This pathologic description predicts abnormal white matter connectivity primarily within projection pathways. We have demonstrated a clinically-relevant impact of polymicrogyria on the arcuate fasciculus in pediatric patients with polymicrogyria. These preliminary results suggest a significant effect on the establishment of cortico-cortical connections and furthermore imply abnormal cortical structure beyond layer 5 in patients with polymicrogyria. These data promulgate the potential for tract-based measures of connectivity to probe cortical structure.

14:00 4331.   Do DTI Indices Correlate with Neurological Status of Neonates with Congenital Heart Disease Before and After Cardiopulmonary Bypass Surgery? 
Rabia Liamlahi1, Walter Knirsch1, Bea Latal2, Michael von Rhein3, Ianina Scheer4, Hintendu Dave5, Achim Schmitz6, Vera Bernet7, Christian Kellenberger4, and Malek I Makki4
1Cardiology, University Children Hospital, Zurich, Switzerland, 2Child Development, University Children Hospital, Zurich, Switzerland, 3Child Development Center, University Children Hospital, Zurich, Switzerland, 4Diagnostic Imaging, University Children Hospital, Zurich, Switzerland, 5Congenital Cardiovascular Surgery, University Children Hospital, Zurich, 6Anesthesia, University Children Hospital, Zurich, Switzerland, 7Pediatric Intensive Care, University Children Hospital, Zurich, Switzerland

Using DTI we studied the cortico-spinal tracts (posterior limb internal capsule, cerebral peduncle and inferior cortico-spinal) of neonates with severe congenital heart disease before and after cardiopulmonary bypass surgery during first weeks of life. In addition we performed neurodevelopmental assessment, and generated a combined score of bearing, muscle tone and movement, and correlated it with white-matter microstructural changes. Before surgery there was no significant correlation between any DTI indices (ADC, FA, parallel and perpendicular diffusions). After surgery, our results clearly demonstrate an association between low FA in the left cerebral peduncle and poor motor fucntion (p < 0.001).

14:30 4332.   Application of Snapshot Inversion recovery (SNAPIR) in neonatal patients with Snaphot-to-Volume-Reconstruction (SVR): a pilot study at 3 Tesla 
Ash Ederies1, Amy K McGuinness2, Nora Tusor1, Joanna M Allsop2, Serena J Counsell2, Rita G Nunes2, Zhi Qing Wu2, Jo V Hajnal2, Mary A Rutherford2, and Christina Malamateniou2
1Neonatal Imaging Group, Imaging Sciences Department, MRC Clinical Sciences Centre, Hammersmith Hospital, Imperial College London, London, United Kingdom, 2Robert Steiner MRI Unit, Imaging Sciences Department, MRC Clinical Sciences Centre, Hammersmith Hospital, Imperial College London, London, United Kingdom

Previous studies on fetal patients have shown that Snapshot Inversion Recovery (SNAPIR) is a potentially robust motion-resistant T1-weighted alternative, offering improved anatomy delineation. Although multi-shot are the preferred acquisitions for imaging the neonatal brain, single-shot acquisitions such as SNAPIR may be advantageous for delineating the anatomy in the presence of neonatal motion. To compensate for the lower signal-to-noise-ratio and resolution introduced by single-shot techniques, dynamic scanning and image registration in the form of Snapshot-to-Volume-Reconstruction (SVR) may be used in combination. This pilot study discusses the benefits and challenges of SNAPIR and SVR in neonates and suggests areas for future optimisation.

15:00 4333.   Comparison of DTI Metrics in Neonates Obtained with Manual ROI Analysis vs Modified TBSS 
Nancy K Rollins1,2, Youngseob Seo1,2, Lina Chalak1,2, Jonathan M Chia3, Gareth Ball4, and Zhiyue J Wang1,2
1University of Texas Southwestern Medical Center, Dallas, Texas, United States, 2Children's Medical Center, Dallas, Texas, United States, 3Philips Healthcare, Cleveland, Ohio, United States, 4Imperial College and MRC Clinical Science Center, London, United Kingdom

Diffusion tensor imaging (DTI) is being used to study brain maturation and disease effects on white matter. Manual region-of-interest (ROI) analysis which is widely used is operator-dependant, tedious, hypothesis driven, and impractical for comparison of groups or large numbers of subjects but does not require potentially confounding spatial normalization. Tract Based Spatial Statistics (TBSS) is an open source operator-independent platform which spatially normalizes tensor data; potentially problematic in neonates as the normalization templates used in adults have not been proven reliable to infants. We performed a direct comparison between manual ROI analysis and TBSS in infants using the modifications proposed by Ball to improve the reliability of TBSS in neonates and then report region-specific tensor metrics in infants 32 -49 weeks post conception age at the time of imaging.

Thursday May 12th
  13:30 - 15:30 Computer 110

13:30 4334.   Quantitative Assessment of the Cortico-Spinal Tracts in Neonates With Congenital Heart Disease Following Cardiopulmoray Bypass Surgery. 
Malek I Makki1, Rabia Liamlahi2, Hintendu Dave3, Ianina Scheer1, Walter Knirsch2, Bea Latal4, Achim Schmitz5, Vera Bernet6, and Christian Kellenberger1
1Diagnostic Imaging, University Children Hospital, Zurich, Switzerland, 2Cardiology, University Children Hospital, Zurich, Switzerland, 3Congenital Cardiovascular Surgery, University Children Hospital, Zurich, 4Child Development Center, University Children Hospital, Zurich, Switzerland, 5Anesthesia, University Children Hospital, Zurich, Switzerland, 6Pediatric Intensive Care, University Children Hospital, Zurich, Switzerland

We performed DT-MRI to study major white matter tracts of neonates with congenital heart disease. This investigation was carried out before and after cardiopulmonary bypass surgery. The inferior corticospinal tracts (CS), the cerebral peduncle (CP) and the posterior limb of internal capsule (PLIC) were studied bilaterally. In both pre-surgery and post-surgery groups we observed that: 1) left and right CS are statistically identical and 2) left and right CP are statistically identical. The PLIC demonstrated an asymmetric delay of white matter maturation observed pre-surgery (FAleft < FAright, p = 0.003) and post-surgery (FAleft < FAright, p = 0.022).

14:00 4335.   The application of T2 Star Weighted Angiography (SWAN) in Hypoxic-ischemic encephalopathy 
Zhengrong Xia1, Yuhua Li1, and He Wang2
1Department of Radiology, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, Shanghai, China, People's Republic of, 2Global Applied Science LaboratoryGlobal Applied Science Laboratory, GE Healthcare

The value of T2 Star Weighted Angiography(SWAN) in hypoxic-ischemic encephalopathy(HIE) was investigated. 105 neonates who suspected HIE underwent MR scanning on a GE HDx twin speed 3.0T MR scanner. All of these patients were evaluated with SWAN in addition to other conventional MRI techniques, including FLAIR, FSE, DWI. SWAN had higher sensitivity than other sequences for the detection of germinal matrix hemorrhage, intraventricular hemorrhage, which is a strong predictor for long-term neurologic and neuropsychologic outcomes. Furthermore, SWAN demonstrated that the lesions in preventricular white matter rarely contain hemorrhage. SWAN is recommended to become a part of routine HIE MRI protocols.

14:30 4336.   3D proton MR spectroscopy of normal-appearing brain in Tuberous Sclerosis Complex 
Ivan Kirov1, Sarah Milla1, Joseph Oved2, Orrin Devinsky3, Howard Weiner3, and Oded Gonen1
1Radiology, New York University, New York, NY, United States, 2School of Medicine, New York University, New York, United States, 3Neurosurgery, New York University, New York, NY, United States

Refractory epilepsy in Tuberous Sclerosis Complex (TSC) is treated by resection of the seizure locus localized by electro-encephalography. The traditional surgery target is the tuber, which is considered to be intrinsically epileptogenic. A subset of patients, however, experience epilepsy, but are tuber-free on conventional MRI and are often excluded from surgery. We used three-dimensional proton MR spectroscopy (1H-MRS) to examine the normal-appearing tissue in these patients. Our initial results reveal metabolic abnormalities in the tuber-free brain in TSC. 1H-MRS in this subset of patients may be a useful marker for identifying MR-occult pathology.

15:00 4337.   A Lobar-Based Curvature Analysis of Normal and Polymicrogyria Brain Surfaces in Children 
Michael Paldino1,2, Daniel Ginsburg1, Patricia Ellen Grant1,2, and Rudolph Pienaar1,2
1Radiology, Children's Hospital Boston, Boston, MA, United States, 2Radiology, Harvard Medical School, Boston, MA, United States

We perform a curvature-based analysis on a group of normal and a group of polymicrogyria brain surfaces. Our analysis is lobar based, and we consider the distribution of several intrinsic and extrinsic curvature functions. We show that PMG, even if presented locally, has general affects on the other brain regions.

Electronic Posters : Neuroimaging
Click on to view the abstract pdf and click on to view the video presentation.
Imaging of Psychiatric Disorders

Monday May 9th
Exhibition Hall  14:00 - 16:00 Computer 111

14:00 4338.   Brain functional connectivity reveals abnormal brain development in high risk bipolar infants 
Wei Gao1, John Gilmore2, Shun Xu3, and Weili Lin4
1Radiology and BRIC, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 2Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States, 3Computer Science, University of North Carolina at Chapel Hill, 4Radiology and BRIC, University of North Carolina at Chapel Hill

Given the high heritability of bipolar disorder (BD), the study of the offspring of BD parents (i.e., high-risk children) may provide an excellent model to delineate its pathophysiology during early development. In this study, 46 high-risk children aged at ~3wks, 1yr, and 2yrs were recruited to undergo a resting-state functional magnetic-resonance imaging (rs-fMRI) scan and graph theory analysis was employed to delineate potential abnormal functional connectivity development, particularly the global (GE) and local wiring efficiency (LE) for information transfer in the brain. Without any explicit symptoms at such young ages, we detected significant functional connectivity abnormality, which might potentially serve as more objective early diagnosis measures.

Milan Scheidegger1,2, Simone Grimm2,3, Alexander Fuchs1, Rainer Kraehenmann2, Heinz Boeker2, Erich Seifritz2, Peter Boesiger1, Martin Walter4, and Anke Henning1
1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland, 2Clinic of Affective Disorders and General Psychiatry, Psychiatric University Hospital Zurich, Zurich, Switzerland, 3Cluster Languages of Emotion, Freie Universität Berlin, Berlin, Germany, 4Clinical Affective Neuroimaging Laboratory, Psychiatric University Hospital, Magdeburg, Germany

Ketamine is a potent glutamatergic NMDA receptor antagonist with rapid antidepressant properties at subanaesthetic doses, thus providing a valuable research tool for the investigation of the neurobiology of major depressive disorder (MDD). This multimodal imaging study in 14 healthy subjects reveals the neuropharmacological effects of a single intravenous subanaesthetic ketamine infusion on fMRI-BOLD responses during an emotional processing task and their relationship to glutamatergic metabolite concentrations in the pregenual anterior cingulate cortex (PACC) assessed by proton magnetic resonance spectroscopy (1H-MRS) and indicates a close relationship between BOLD reactivity and glutamatergic metabolism after pharmacological stimulation.

15:00 4340.   Blunted hemodynamic response to a methylphenidate challenge in regular users of amphetamine: an ASL based pharmacological MRI study 
Marieke L.J. Schouw1, Matthan W.A. Caan1, Aart J. Nederveen1, and Liesbeth Reneman1
1Radiology, AMC, Amsterdam, Netherlands

In this study we used arterial spin labelling to compare the change in cerebral blood flow (CBF) in response to an oral challenge with methylphenidate between healthy controls and amphetamine users. CBF data before and after the challenge were averaged. We registered data to both individual space and standard space, looking at mean CBF in caudate, putamen, thalamus and hippocampus. In line with previous (PET) studies, a marked decrease in CBF in response to methylphenidate was seen in healthy controls, not amphetamine users. This blunted response is most likely caused by changes to the dopaminergic system induced by amphetamine use.

15:30 4341.   New Insight into Mechanism of Epileptogenesis with Dynamic T1 Contrast Perfusion MRI in Calcified Neurocysticercosis 
Rakesh Kumar Gupta1, Rishi Awasthi1, Prativa Sahoo2, Avantika Verma3, Vimal Kumar Paliwal4, Ramesh Venkatesan5, Kashi Nath Prasad3, and Ram KS Rathore2
1Radiodiagnosis, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India, Lucknow, Uttar Pradesh, India, 2Mathematics & Statistics, Indian Institute of Technology, Kanpur, Kanpur, Uttar Pradesh, India, 3Microbiology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India, Lucknow, Uttar Pradesh, India, 4Neurology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India, Lucknow, Uttar Pradesh, India, 5Wipro-GE Healthcare, Bangalore, Karnataka, India

DCE-MRI was performed on 30 patients with Neurocysticercosis (NCC), cysts which were found to be calcified on imaging. Various perfusion indices were analyzed and it was found that Kep, ve and MMP-9 expression were significantly higher in symptomatic as compared to asymptomatic patients. Moreover, a strong correlation of serum MMP-9 with Kep portend that Kep can be used to differentiate between symptomatic and asymptomatic patients.

Tuesday May 10th
  13:30 - 15:30 Computer 111

13:30 4342.   DTI detection of fear conditioning induced microstructural plasticity 
Abby Ying Ding1,2, Iris Y Zhou1,2, Qi Li3,4, Grainne M McAlonan3,4, and Ed X Wu1,2
1Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, Hong Kong SAR, China, People's Republic of, 2Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, Hong Kong SAR, China, People's Republic of, 3Department of Psychiatry, The University of Hong Kong, Hong Kong, Hong Kong SAR, China, People's Republic of, 4Centre for Reproduction Growth and Development, The University of Hong Kong, Hong Kong, Hong Kong SAR, China, People's Republic of

Fear conditioning is widely used to study the neural basis of learning and memory. Neural and cellular changes associated with learning memory have been suggested in specific regions by behavioral and histological studies. We employ DTI to assess the acute changes following fear conditioning. Significant FA changes were found in specific regions such as fimbria, amygdala, hippocampus, cingulum and piriform cortex. Our results indicated that plasticity began shortly after fear learning in limbic and white matter regions, and DTI is a valuable tool for detecting such microstructural plasticity.

14:00 4343.   Correlation between clinical data and metabolic abnormalities in inferior colliculus for schizophrenic patients with auditory hallucinations 
Bernardo Celda1, MCarmen Martínez-Bisbal2, Julio Sanjuan3, Eduardo J Aguilar4, Luis Martí-Bonmatí5, Enrique Mollá6, and Beatriz Martínez-Granados7
1Química Física, Universitat Valencia-CIBER-BBN, Burjassot, Valencia, Spain, 2Química Física, CIBER-BBN/Universitat de Valencia, Burjassot, Valencia, Spain, 3Psychiatry, Universitat de Valencia-CIBERSAM, Valencia, Valencia, Spain, 4Psychiatry, Hospital Sagunto-CIBERSAM, Sagunto, Valencia, Spain, 5Radiology, Hospital Dr. Peset, Valencia, Valencia, Spain, 6Radiology, Hospital La Ribera, Alzira, Valencia, Spain, 7Química Física, Universitat de Valencia, Burjassot, Valencia, Spain

The aim of this work is to study biochemical changes in inferior colliculus (IC) and the association with dimensions of auditory hallucinations (AH) in schizophrenics. MR spectroscopic imaging studies (1.5T,TE272ms) were performed in 30 right-handed chronic-schizophrenics (19 with AH, 11 without AH) and 28 controls. Right IC showed significant NAA/Cr reduction in hallucinators compared to controls. Schizophrenics showed loss of metabolic laterality observed in controls. Metabolic data in right IC were correlated with emotional AH items. The contribution of IC on neural underpinnings of AH is particularly relevant for right IC and is centred on attention-emotional component of this symptom.

14:30 4344.   Effects of Prenatal Cocaine Exposure on Human Brain Structures 
Xiangchuan Chen1, Claire D Coles2, Mary E Lynch2, Zhihao Li1, and Xiaoping Hu1
1Biomedical Imaging Technology Center, Emory University, Atlanta, Georgia, United States, 2Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, Georgia, United States

Investigation of brain structural outcomes induced by prenatal cocaine exposure (PCE) was performed by automatically segmenting the cerebral cortex and sub-cortical structures into various regions of interest (ROIs) with Freesurfer on T1-weighted images. No significant PCE effect was found on the volumes of sub-cortical ROIs. In contrast, the entire left and right cerebral cortices and a few cortical ROIs exhibited reduced volume by PCE. In addition, a gender difference in PCE effect was found, suggesting that female may be more vulnerable to PCE than male. Thus, the gender factor should be considered in future studies in this field.

15:00 4345.   Gray Matter Differences due to weeks of Excessive Long-distance Running and after recovery revealed by Voxel-Based Morphometry (VBM) 
Arthur Peter Wunderlich1, Sonja Faust2, Wolfgang Freund1, Uwe Schütz1, and Christan Billich1
1Dept. for Diagnostic and Interventional Radiology, Univ.-Clinic Ulm, Ulm, Germany, 2Univ.-Clinic Ulm, Germany

This paper deals with the investigaton of the gray matter brain plasticity as observed in candidates of an ultra-long-distance run. Before, during and after the trans-European foot race, some competitors were examined with high-resolution MRI. Data were analysed by means of voxel-based morphometry. Volume changes were most significant in the second half of the race. Gray matter volume reduction of visual association fields was the most prominent finding. Local volume gain was detected in Brodman Areas 10 and 42, which have been associated to volition. The changes were reversible upon follow-up after six months.

Wednesday May 11th
  13:30 - 15:30 Computer 111

13:30 4346.   Real-time Monitoring of In Vivo Human Brain Amino Acid Neurotransmitter Response to a Single Intravenous Dose of Ketamine in Major Depressive Disorder Using the 1H MRS J-editing Technique 
Dikoma C Shungu1, Matthew S Milak2, Larence S Kegeles2, Caitlin Proper2, Xiangling Mao1, and J John Mann2
1Radiology, Weill Cornell Medical College, New York, NY, United States, 2Psychiatry, College of Physicians and Surgeons of Columbia University, New York, NY

Acute intravenous administration of single sub-anesthetic doses of ketamine (KET) has been recently investigated as a potentially fast-acting treatment for major depressive disorder (MDD). The near immediate anti-depressant effects of KET, a noncompetitive glutamate (Glu) NMDA receptor antagonist, are postulated to involve the drug’s stimulation of a rapid increase in brain Glu that may then enhance transmission at metabotropic Glu receptor subtypes. Here, we report the results of a pilot in vivo human brain 1H MRS study that aimed to dynamically monitor Glu changes following acute intravenous administration of KET.

14:00 4347.   Brain Stem Motion in Acqueductal Stenosis Hydrocephalus 
Guillaume Calmon1,2, Olivier Balédent3, Marc Labrousse1,4, Catherine Gondry-Jouet3, Anthony Fichten3, Gabriela Hossu5, Jacques Felblinger1,5, and Marc Braun1,6
1IADI, INSERM U947, Nancy, France, 2GE Healthcare, Buc, France, 3Amiens University Hospital, Amiens, France, 4Faculty of Medecine and University Hospital, Reims, France, 5INSERM CIT801, CIC-IT, Nancy, France, 6Faculty of Medecine and University Hospital, Nancy, France

Phase-contrast MRI was used at the level of the brain stem in 22 volunteers and compared to 15 patients with non-communicating hydrocephalus. ROIs were manually drawn in the pons. Brain stem motion during the cardiac cycle was assessed in the cranio-caudal direction. Brain stem motion amplitude is significantly reduced in patient vs. volunteers (p = 0.009). Brain stem motion amplitude is reduced in healthy female versus healthy male (p = 0.018). Brain stem motion peaked 67 ms later in patients compared to volunteers. In conclusion, brain stem motion amplitude is reduced and the waveforms are modified in non-communicating hydrocephalus.

14:30 4348.   A multimodal imaging study of never-medicated adults with schizophrenia 
Elisa Canu1, Roberto Gasparotti2, Federica Agosta1, Paolo Valsecchi3, Giancarlo Comi4, Elisabetta Pagani1, Emilio Sacchetti3, and Massimo Filippi1
1Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, Scientific Institute and University Hospital San Raffaele, Milan, Italy,2Department of Diagnostic Imaging, University of Brescia, Spedali Civili, Brescia, Italy, 3Department of Psychiatry, Brescia University School of Medicine, Brescia, Italy,4Department of Neurology, Scientific Institute and University Hospital San Raffaele, Milan, Italy

Voxel based morphometry and Tract-based Spatial Statistics were used to assess volumetric and microstructural damage in 37 never-medicated schizophrenic patients vs. 17 healthy controls. Compared with controls, schizophrenic patients showed gray and white matter volume loss in the middle temporal lobes. Patients vs. controls also showed an increased mean diffusivity in the fornix, and a decreased fractional anisotropy in the corpus callosum, posterior cingulum, and parahippocampal region bilaterally. Schizophrenic patients demonstrated a complex pattern of parieto-temporo-occipital damage. Such a pattern is consistent with regions related to auditory hallucinations, and neurofunctional networks thought to be involved in the pathophysiology of schizophrenia.

15:00 4349.   Correlating Functional and Structural Connectivity of Default Mode Network with Dosage of Two Candidate Vulnerability Genes of Schizophrenia 
Su-Chun Huang1,2, Chih-Min Liu3, Hai-Go Hwu3, Chen-Chung Liu3, Fa-Hsuan Lin1, and Wen-Yih Isaac Tseng1,2
1Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan, 2Center for Optoelectronic Biomedicine, National Taiwan University College of Medicine, Taipei, Taiwan, 3Department of Psychiatry, National Taiwan University Hospital, Taipei, Taiwan

With the combined resting-state fMRI and diffusion spectrum imaging, the relationships were investigated between functional connectivity (FC), structural connectivity (SC) of the default mode network (DMN) and the dosage of candidate vulnerability genes (NRG1 and DISC1). Significant correlations were found between the gene dosage and FCs in two pairs of the DMN, i.e. the right medial frontalleft inferior parietal pair and the right inferior parietalright posterior cingulate cortex pair. Further, a significant correlation was found between the gene dosage and SC of bilateral posterior cingulate cortices. No significant correlation was found between the gene dosage and PANSS. Our results suggest that the gene dosage might influence FC and SC of the DMN, but not directly reflect clinical symptoms.

Thursday May 12th
  13:30 - 15:00 Computer 111

13:30 4350.   Proinflammatory cytokines correlates with MR imaging in patients with extrahepatic portal venous obstruction patients having minimal hepatic encephalopathy 
A Yadav1, S K Yadav2, A Srivastava3, S K Yachha3, M A Thomas4, V A Saraswat5, and R K Gupta1
1Departments of Radiodiagnosis, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India, Lucknow, UP, India, 2Departments of Radiodiagnosis, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India, lucknow, UP, India, 3Pediatric Gastroenterology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India, lucknow, UP, India, 4Department of Radiological Sciences, David Geffen School of Medicine at UCLA, California, California, Los Angels, United States, 5Gastroenterology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India, lucknow, UP, India

Minimal hepatic encephalopathy has been reported in extrahepatic portal venous obstruction patients, it is well established in cirrhotic patients. Proinflammatory cytokines and hyperammonemia play very important role in the pathogenesis of minimal hepatic encephalopathy in these patients. In extrahepatic portal venous obstruction, there is hyperammonemia and inflammation as evident by higher blood ammonia, TNF-α and IL6 levels. Significant correlation of blood ammonia, brain Glx, and mean diffusivity in various brain regions with pro-inflammatory cytokines suggests that both hyperammonemia and proinflammatory cytokines play a role in pathogenesis of cerebral edema leading to minimal hepatic encephalopathy in extrahepatic portal venous obstruction

14:00 4351.   MRI Morphological and Functional Connectivity Analysis of Thalamus in Mild Traumatic Brain Injury 
Yongxia Zhou1, Lin Tang1, Daniel K Sodickson1, Joseph Reaume1, Robert I Grossman1, and Yulin Ge1
1Radiology/Center for Biomedical Imaging, New York University School of Medicine, New York, NY, United States

Shape and thickness analysis as well as resting-state fMRI were performed for thalamic morphological and thalamocortical pathway changes in 23 patients with MTBI as compared to 18 normal controls. We were able to demonstrate slightly morphological changes (shape shrinkage with decreased thickness) of thalamus in MTBI patients. We also found disruption of thalamocortical functional networks indicated by reduced projected voxel number from BA39 (parietal angular area) and increased correlation strength with BA20 (inferior temporal area) in patients. Our results provide preliminary evidence of thalamic injury with both structural and functional changes in MTBI, which may have clinical relevance to cognition.

14:30 4352.   γ-Aminobutyric Acid (GABA) Modulates Functional Connectivity Network Strength in Adolescent Major Depressive Disorder 
Vilma Gabbay1, Benjamin Ely1, Soraja Bangaru1, Michael Milham1, Xiangling Mao2, Francisco X Castellanos1, and Dikoma C Shungu2
1Child Study Center, New York University School of Medicine, New York, NY, United States, 2Radiology, Weill Cornell Medical College, New York, NY, United States

This study aimed to examine the relationship between striatal functional connectivity (FC) and anterior cingulate cortex (ACC) GABA concentrations in adolescents with MDD and healthy controls. It was hypothesized that the ACC GABAergic system modulates fronto-striatal connectivity, and that this modulation is disrupted in adolescents with MDD.