Electronic Poster Session - Neuro B
  Neuro: Miscellaneous 3632-3655
  fMRI of Brain Disorders 3656-3678
  Head & Neck Imaging 3679-3695
  Clinical Diffusion & Microstructure 3696-3719
  Clinical Diffusion & Tractography 3720-3740
  Aging & Dementia 3741-3764

Neuro: Miscellaneous
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  10:00 - 11:00

  Computer #  
3632.   25 MRI biomarkers capable of detecting effects of an experimental pharmacologic therapy for idiopathic Normal Pressure Hydrocephalus
Milos Ivkovic1, Heather Katzen2, Ilhami Kovanlikaya1, Ahmet Bagci2, Linda Heier1, Noam Alperin2, Ashish Raj1, and Norman Relkin1
1Weill Cornell Medical College, New York City, NY, United States, 2University of Miami School of Medicine, Miami, FL

There are no proven pharmacologic treatments for Normal Pressure Hydrocephalus (NPH). Acetazolamide (ACZ) is known to reduce CSF production and interstitial edema. We hypothesized that a low dose of ACZ would reduce CSF production and brain interstitial fluid in NPH. By using a combination of DW-MRI, T1 and T2-FLAIR images, we unequivocally determined that ACZ reduced WM abnormalities and interstitial brain water in NPH patients. T2-FLAIR and T1 volumetrics showed consistent reduction in WM pathology. By the use of DW-MRI, we were able to detect changes within the remaining areas of WM signal abnormalities which would otherwise have gone unnoticed.

3633.   26 Cerebellar white matter abnormalities following primary blast injury
Christine MacDonald1, Ann Johnson1, James Sorrell1, Thomas Malone1, Dana Cooper1, Elliot Nelson2, Nicole Werner1, Joshua Shimony3, Matthew Parsons3, Abraham Snyder3, Marcus Raichle3, Raymond Fang4, Stephen Flaherty5, Michael Russell6, and David Brody1
1Neurology, Washington University, Saint Louis, MO, United States, 2Psychiatry, Washington Univeristy, Saint Louis, MO, United States, 3Radiology, Washington University, Saint Louis, MO, United States, 4Landstuhl Regional Medical Center, Landstuhl, Germany, 5Cape Fear Valley Medical Center, Fayetteville, NC, United States, 6HQ, US MEDCOM, United States

The effects of blast exposure on human brain in the absence of head impact are unknown. Previous clinical studies, experimental animal models, and computational modeling of blast describe changes to cerebellum and brainstem. In a unique group of US military personnel with isolated, primary blast-related traumatic brain injury and no other insult, we found DTI abnormalities consistent with white matter injury in 75% of subjects specifically in the cerebellum. These findings support the hypothesis that there may be a specific contribution of blast to brain injury in the absence of head impact and that cerebellum may be particularly vulnerable.

3634.   27 White Matter Damage in Gulf War Illness Patients: A Quantitative MRI Relaxometry Study
Kaundinya Gopinath1,2, Saurabh Vaidya2, Sandeepkumar Ganji2, Sergey Cheshkov2, Robert Haley3, and Richard Briggs2,3
1Department of Radiology & Imaging Sciences, Emory University, Atlanta, GA, United States, 2Department of Radiology, UT Southwestern Medical Center, Dallas, TX, United States, 3Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, United States

Gulf War Illness (GWI) is a multi-symptom disorder characterized by cognition, emotion and sensory deficits. This study used a multi-slice multi-echo T2-mapping sequence to examine WM integrity in GWI veterans with Syndromes1 (Syn1), Syn2 and Syn3, and age-matched controls. The control group’s WM T2s were similar to those observed in T2 relaxometry studies of intact WM. Syn2 and Syn3 groups exhibited WM impairment in the form of increased T2 relaxation times compared to controls, in important WM areas such as the cholinergic pathway which serve a number of cognitive functions. Thus WM impairment could be an important marker for GWI.

3635.   28 Verification of Chronic Hippocampus Perfusion Abnormalities in Ill Gulf War Veterans from a Representative National Sample
Xiufeng Li1,2, Jeffrey S. Spence3,4, David M. Buhner4, Robert W. Haley4, and Richard W. Briggs2,4
1Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States, 2Radiology, UT Southwestern Medical Center, Dallas, TX, United States, 3Clinical Sciences, UT Southwestern Medical Center, Dallas, TX, United States, 4Internal Medicine, UT Southwestern Medical Center, Dallas, TX, United States

New ASL hippocampus perfusion study results of Gulf War veterans recruited from a representative national sample of over 8,000 veterans corroborate previous SPECT and ASL results of Gulf War veterans selected from the 24th U.S. Naval Reserve Mobile Construction Battalion that show chronic and perhaps progressive hippocampal perfusion dysfunction both at baseline and in response to challenge with the short-acting, reversible cholinesterase inhibitor physostigmine. The ASL physostigmine challenge test is a valuable biomarker for the diagnosis of Gulf War illness and is practical enough to be implemented diagnostically in a clinical setting.

3636.   29 Diffusion Tensor Tractography Studies correlate with Neuropsychometric tests in patients of vitamin B12 deficiency with normal appearing brain on conventional MRI
Pradeep K. Gupta1, R. K. Garg2, R. Verma2, V. K. Paliwal3, M. K. Singh2, Y. Rai1, R. S. Rathore4, and R. K. Gupta1
1Department of Radiodiagnosis, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, UP, India, 2Department of Neurology, Chattrapati Sahuji Maharaj Medical University, Lucknow, UP, India, 3Department of Neurology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, UP, India, 4Department of Mathematics & Statistics, Indian Institute of Technology, Kanpur, UP, India

Vitamin B-12 deficiency may leads to microstructural changes in brain white matter. The purpose of this study was to determine the change in DTI metrics in brain white matter and to find out its association with cognitive function among patients with vitamin B-12 deficiency. In this study, we included 8 patients with vitamin B-12 deficiency and 9 healthy controls. ATR and PTR fibers showed significant reduction in FA values with abnormal cognitive function in these patients. These changes in ATR and PTR in patients with vitamin B12 deficiency with normal appearing conventional MRI suggest these findings may be used as image biomarkers of B12 deficiency in future.

3637.   30 Structural brain signature of FTLD driven by granulin mutation
Valentina Battistoni1, Barbara Borroni2, Giovanni Giulietti1, Antonella Alberici2, Enrico Premi2, Carlo Cerini2, Silvana Archetti3, Roberto Gasparotti4, Carlo Caltagirone5,6, Alessandro Padovani2, and Marco Bozzali1
1Neuroimaging Laboratory, Santa Lucia Foundation IRCCS, Rome, Italy, 2Centre for Ageing Brain and Neurodegenerative Disorder, Neurology Unit, University of Brescia, Brescia, Italy, 3III Laboratory of Biotechnology, Brescia Hospital, Brescia, Italy, 4Neuroradiology Unit, University of Brescia, Brescia, Italy, 5Department of Clinical and Behavioural Neurology, Santa Lucia Foundation IRCCS, Rome, Italy, 6Department of Neuroscience, University of Rome 'Tor Vergata', Rome, Italy

Using diffusion MRI, we investigated the contribution of white matter damage in accounting for the clinical features driven by the GRN Thr272fs mutation in fronto-temporal lobar degeneration (FTLD). VBM showed atrophy of left medial frontal grey matter in mutation carriers (VBM analysis) compared to non-mutation carrier patients. Voxel-wise group comparisons showed anterior regions of FA reduction and increased MD in mutation carrier patients in the anterior corpus callosum. Post-hoc analysis showed a correlation between grey and white matter abnormalities in mutation carrier patients. Although this correlation does not imply causality between the two events, this cannot be ruled out.

3638.   31 TBSS analysis in MSA
Aaron M Rulseh1, Jiri Keller2, Robert Rusina3, Hana Brozova4, Robert Jech4, and Josef Vymazal2
1Dept. of Radiology, Na Homolce Hospital, Prague, Czech Republic, 2Na Homolce Hospital, Czech Republic, 3Faculty Thomayer Hospital, Czech Republic,4Dept. of Neurology, Charles University in Prague, 1st Faculty of Medicine, Czech Republic

Multiple System Atrophy (MSA) is a sporadic, progressive disease characterized by autonomic dysfunction with varying degrees of parkinsonian and/or cerebellar features, and has been postulated that MSA is a primary oligodendrogliopathy. Twenty patients with probable MSA and twenty healthy volunteers were included. White matter changes in MSA are widespread and not limited to discrete regions. Dramatic changes in RD with nearly unaltered AD support previous studies reporting oligodendrocytes are primarily affected in MSA. Further studies examining white matter changes in diverse regions may extend the utility of DTI in the diagnosis of MSA.

3639.   32 CSF and brain atrophy investigation in neurodegenerative diseases
Bader Chaarani1, Jadwiga Zmudka1, Joel Daouk1, Catherine Gondry-Jouet2, Roger Bouzerar1, and Olivier Baledent1
1University Hospital, Amiens, France, 2Radiology, University Hospital, Amiens, France


3640.   33 Comparing MR Estimate of Intracranial Pressure with Valve Opening Pressure in Shunted Patients
Noam Alperin1, Marc Muehlmann2, Inga Koerte2, Markus Lehner2, Aurelia Peraud2, and Birgit Ertl-Wagner2
1University of Miami, Miami, FL, United States, 2University of Munich, Munich, Germany

Reliable noninvasive MR measurement of intracranial pressure (MRICP) may have an important diagnostic role in neurosurgical problems related to altered CSF dynamics. The reliability of the MRICP methodology was assessed by comparing derived MRICP values with shunt opening pressure setup in shunted patients with various CSF related disorders. Under the assumption that ICP values in these patients is well approximated by the shunt opening pressure, a reliable noninvasive estimate of ICP should demonstrate a good correspondence between these two values.

3641.   34 Diffusion Tensor Imaging of the Human Optic Nerve in vivo Using SENSE Accelerated Multi-shot 2D Navigated EPI
Ha-Kyu Jeong1,2, Blake E. Dewey1,3, Jane A. T. Hirtle1,4, Adam W. Anderson1,5, John C. Gore1,2, and Seth A. Smith1,2
1Vanderbilt University Institute of Imaging Science, Nashville, TN, United States, 2Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States, 3Physics and Astronomy, Vanderbilt University, Nashville, TN, United States, 4Psychology and Human Development, Vanderbilt University, Nashville, TN, United States, 5Biomedical Engineering, Vanderbilt University, Nashville, TN, United States

Imaging optic nerve has been considered as technically challenging due to small size, presence of air-filled sinuses and confounding signals from surrounding structures. Typically, single-shot EPI has been used for DW optic nerve imaging combined with ZOOM, reduced FOV or outer-volume-suppression techniques. However, these studies still suffer low SNR and residual EPI-related artifacts. This study presents the first DW multi-shot optic nerve imaging with SENSE and 2D navigator for reduced EPI artifacts and correction of motion-induced linear and non-linear shot-to-shot phase variations. Using developed pulse sequence and reconstruction methods, clear DW optic nerve images are presented free of ghosting and reasonable diffusion indices.

3642.   35 Diffusion-weighted MR Neurography of Extremity Nerves and the Initial Clinical Applications
lian xin zhao1, guang bin wang1, Queenie Chan2, and wei bo chen2
1Shandong Medical Imaging Research Institute, Shandong University, jinan, shandong, China, 2Philips Healthcare

The purpose of this study was to demonstrate the feasibility of diffusion-weighted (DW) magnetic resonance (MR) neurography of extremity nerves and evaluate the potential clinical applications. DW MR neurography images were displayed using a three-dimensional (3D) maximum intensity projection and evaluated in forty-seven healthy volunteers and eight patients. The results indicate that DW MR neurography is feasible for providing 3D visualization of major extremity nerves. This study suggests that the use of DW MR neurography, as complementary to conventional MR imaging, will improve depiction and evaluation of nerve anatomy and pathology, and their anatomic relationship with a comprehensive overview.

3643.   36 Assembling the large-scale human connectome: How do we partition the brain?
Etay Ziv1, Olga Tymofiyeva1, Christopher P Hess1, Donna M Ferriero2, A James Barkovich1, and Duan Xu1
1Department of Radiology & Biomedical Imaging, UCSF, San Francisco, CA, United States, 2Department of Pediatrics, UCSF, San Francisco, CA, United States

Structural connectivity networks derived from diffusion MRI vary with choice of brain parcellation. In adults, parcellation and subsequent assembly of the large-scale human connectome relies heavily on brain atlases. However, in the context of the rapidly developing pediatric brain, such approaches introduce problematic biases. Here we present a network-driven brain parcellation that does not rely on brain atlases and propose a method to define the optimal number and size of nodes.

3644.   37 Pharmacological Magnetic Resonance Imaging (phMRI) in healthy subjects using an i.v. challenge with d-amphetamine
Marieke Schouw1, Anne Marije Kaag1, Matthan W.A. Caan1, Jan Booij2, A. J. Nederveen1, and Liesbeth Reneman1
1Department of Radiology, Academic Medical Center, Amsterdam, Noord-Holland, Netherlands, 2Department of Nuclear medicine, Academic Medical Center, Amsterdam, Noord-Holland, Netherlands


3645.   38 T2* of Myelin Water Edited by Longitudinal Relaxographic Imaging
Christian Labadie1,2, Abdul-Rahman Allouche2, Monique Aubert-Frécon2, and Harald E Möller1
1Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, 2Laboratoire de Spectrométrie Ionique et Moléculaire, Université Claude Bernard, Lyon, France

The interpretation of the early longitudinal relaxation of water in the human brain at high field (B0 ≥ 3 T) is related to an assumption on the exchange rate of water between the confined environment of tight myelin and other spaces: fast exchange is compatible with a magnetization transfer model between semi-solid protons of the myelin membranes and water, whereas slow exchange suggests the distinct observation of mobile water in myelin with a short T1.

3646.   39 Postmortal DWI of the brain and comparison with in vivo data
Jin Yamamura1, Tony Schmidt1, Roland Fischer2, Jerry Wang3, and Gerhard Adam1
1Diagnostic and Interventional Radiology, University Medical Center Hamburg-Eppendorf, Hamburg, Hamburg, Germany, 2Children's Hospital and Research Center Oakland, Oakland, California, United States, 3Department of Radiology, Children's Medical Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States

DWI of the Brain in Forensic Medicine

3647.   40 Influence of Volume Conductor Model Errors on EEG Dipole Source Localization in Neonates
Ivana Despotovic1, Perumpillichira J. Cherian2, Maarten De Vos3, Hans Hallez1, Paul Govaert4, Maarten Lequin5, Gerhard H. Visser2, Renate Renate M. Swarte4, Ewout Vansteenkiste1, Sabine Van Huffel3, and Wilfried Philips1
1Ghent University, MEDISIP-IPI-IBBT, Ghent, Belgium, 2Erasmus MC-Sophia, University Medical Center Rotterdam, Department of Clinical Neurophysiology, Rotterdam, Netherlands, 3Katholieke Universiteit Leuven, ESAT-IBBT-K.U. Leuven Future Health Department, Leuven, Belgium, 4Erasmus MC-Sophia, Department of Neonatology, Rotterdam, Netherlands, 5Erasmus MC-Sophia, Department of Pediatric Radiology, Rotterdam, Netherlands

Integrating MRI and EEG data for 3D localization of active sources in the brain is an important diagnostic tool in patients with neurological disorders. However, this method has not yet been sufficiently studied in neonates. To investigate its feasibility, we developed an integrated method for dipole source localization in neonates based on a realistic head model. Here, we present our method and explore its sensitivity to electrode mislocalization and the variations in neonatal skull conductivity and geometry. Experimental results indicate that EEG source imaging is feasible in neonates and with further developments this technique can be a useful diagnostic tool.

3648.   41 Brain Diffusion and Perfusion Alternations in Chronic Obstructive Pulmonary Disease (COPD)
Geon-Ho Jahng1, Chang-Woo Ryu1, Min-Ji Kim1, Hyug-Gi Kim1, Sun Mi Kim1, Dal Mo Yang1, Dong Wook Sung2, and Woo-Suk Choi2
1Radiology, Kyung Hee University Hospital at Gangdong, Kyung Hee University, Seoul, Seoul, Korea, 2Radiology, Kyung Hee University Hospital, Kyung Hee University, Seoul, Seoul, Korea

A cognitive deficit is a common problem in patients with chronic obstructive pulmonary disease (COPD). To prospectively evaluate if MRI can demonstrate the microstructural volume loss, the diffusion and/or cerebral blood flow (CBF) changes in subjects with COPD compared with cognitively normal (CN) elderly subjects, 6 subjects with severe COPD, 13 with moderate COPD, and 12 CN subjects underwent isotropic volumetric T1-weighted imaging and diffusion tensor imaging (DTI), and arterial spin labeling perfusion imaging. Voxel-based statistical analyses among groups were performed on brain volumes, fractional anisotropy (FA) and trace, and CBF by ANOVA tests.

3649.   42 Micro-structural alterations in the brain of well-treated HIV+ patients with minor neurocognitive disorders: a multi-contrast MRI study at 3T.
Cristina Granziera1,2, Alessandro Daducci3, Samanta Simioni1, Matthias Cavassini4, Alexis Roche2, Djalel Meskaldij3, Melanie Michel5, Alexandra Calmy6, Bernard Hirschel6, Gunnar Krueger2,7, and Renaud Du-Pasquier1
1Department of clinical neurosciences, CHUV, Lausanne, VD, Switzerland, 2Advanced clinical imaging technology, EPFL, Lausanne, VD, Switzerland, 3EPFL STI IEL LTS5, EPFL, Lausanne, VD, Switzerland, 4Department of infectious diseases, CHUV, Lausanne, VD, Switzerland, 5Neuropsychology, HUG, Geneva, Switzerland, 6Infectious diseases, HUG, Geneva, Switzerland, 7Heathcare sector IM&WS S, Siemens Schweiz AG, Renens, VD, Switzerland

Since the introduction of highly active antiretroviral therapies, the prognosis of HIV patients has improved but the prevalence of minor neurocognitive disorders (MND) has increased. In this study, we used a multi-contrast MRI approach at 3T, to assess brain micro-structural characteristics in MND+ HIV+ patients, MND- HIV+ patients and healthy controls (HC). Our findings show the presence of micro-structural brain alterations in MND+ patients compared to MND- and HC, suggesting loss of structural integrity. In addition, they suggest that a multi-contrast MRI approach at high field may be a powerful approach to understand the physiopathology of MND.

3650.   43 Age related morphometric and metabolic changes in pediatric brains
Hedok Lee1, Zvi Jacob1, Haifang Li2, Ruth Reinsel1, Shaonan Zhang1, and Helene Benveniste1
1Anesthesiology, State University of New York at Stony Brook, Stony Brook, New York, United States, 2Radiology, State University of New York at Stony Brook, Stony Brook, New York

There is little information about brain growth and metabolic changes in children less than 8 years of age. We employed computerized whole brain analysis to analyze age related morphometric changes, in addition to characterizing metabolic status using proton magnetic resonance spectroscopy (1HMRS) in children 2-7 years of age. We found structures belonging to the limbic system and motor control are prominent areas of structural growth during this period while metabolite concentrations appear to be relatively stable during the brain maturation.

3651.   44 Evidence for Larger Extra Ventricular Cranial CSF Volume in Idiopathic Intracranial Hypertension
Noam Alperin1, Sudarshan Ranganathan1, Potyra Aroucha1, Alexis Morante2, Joshua Pasol1, and Byron L Lam1
1University of Miami, Miami, FL, United States, 2University of Miami

Idiopathic intracranial hypertension (IIH) is characterized by elevated intracranial pressure (ICP) of unknown cause. It is widely accepted that IIH is associated with impaired absorption of CSF. Impaired CSF absorption is also the assumed cause for normal pressure hydrocephalous in the elderly. However, unlike hydrocephalous, brain ventricles remain small in IIH. Therefore, if IIH is indeed associated with impaired absorption, an increased extra ventricular CSF volume is expected in IIH. Intra and extra ventricular Cranial CSF volumes have been assessed in cohorts of IIH patients and matches control subjects to verify if this is indeed the case.

3652.   45 Evidence for typical and atypical gray and white matter pathology in frontal lobe epilepsy and different types of temporal lobe epilepsy
Susanne G. Mueller1, Karl Young2, Michael M. Weiner2, and Kenneth D. Laxer3
1Center for Imaging of Neurodegenerative Diseases, San Francisco, CA, United States, 2Center for Imaging of Neurodegenerative Diseases, 3Pacific Epilepsy Program, California Pacifc Medical Center

Synopsis: Voxel-based image analysis approaches, demonstrated different, characteristic abnormality patterns different types of non-lesional partial epilepsy. It is unknown to what degree these patterns exist in individual patients. A two-level multi-modality imaging Bayesian network approach is used with the following aims: 1. to characterize the subtype specific structural abnormalities in non-lesional TLE-MTS, TLE-no and FLE using GAMMA. 2. to the second-level Bayesian network which allows for a robust imaging based subtype classification of single subjects by combining the information obtained at the first level. 3. to identify typical, e.g. FLE gray, and atypical patterns in TLE-MTS, TLE-no and FLE.

3653.   46 Global and Regional Mean Diffusivity Changes in Patients with Obstructive Sleep Apnea
Rajesh Kumar1, Alexa Chavez1, Paul M Macey2,3, Mary A Woo2, Frisca L Yan-Go4, and Ronald M Harper1,3
1Neurobiology, University of California at Los Angeles, Los Angeles, CA, United States, 2UCLA School of Nursing, University of California at Los Angeles, Los Angeles, CA, United States, 3Brain Research Institute, University of California at Los Angeles, Los Angeles, CA, United States, 4Neurology, University of California at Los Angeles, Los Angeles, CA, United States

Obstructive sleep apnea (OSA) patients show brain injury in autonomic, cognitive, and mood regulatory regions; however, it is unknown whether the predominant pathology is acute or chronic in newly-diagnosed, treatment-naïve OSA subjects. We examined global and regional mean-diffusivity (MD), which measures average water diffusion within tissue and is capable of differentiating acute from chronic changes, in newly-diagnosed OSA subjects. Global MD values were reduced in OSA, reflected as localized changes in multiple brain sites, and included medullary, cerebellar, basal-ganglia, and limbic regions. The pathological state in newly-diagnosed OSA subjects likely represents acute pathological processes in tissue, possibly induced by hypoxia.

3654.   47 Structural abnormalities in the thalamus of migraine patients: a multi-parametric study at high field.
Cristina Granziera1,2, Alessandro Daducci3, David Romascano2, Alexis Roche2, Gunther Helms4, Gunnar Krueger2,5, and Nouchine Hadjikhani6,7
1Department of clinical neurosciences, CHUV, Lausanne, VD, Switzerland, 2Advanced clinical imaging technology, EPFL, Lausanne, VD, Switzerland,3ST/IEL/LTS5, EPFL, Lausanne, VD, Switzerland, 4Dept. of Cognitive Neurology, MR-Research in Neurology and Psychiatry, Goettingen, Germany,5Healthcare Sector IM&WS S, Siemens Schweiz AG, Renens, VD, Switzerland, 6BMI/SV/GRHAD, EPFL, Lausanne, Vd, Switzerland, 7Radiology, Martinos center, MGH and Harvard medical school, Charlestown, MA, Switzerland

The thalamus is an important relay of pain processing pathways and exerts a pivotal role in cortical excitability control. In this study, we examined the structural characteristics of the thalamus in a group of migraine patients and healthy controls using a multi-parametric approach at high field MRI (3T). We showed that patients suffering from migraine with aura had different micro-structural features in numerous thalamic nuclei compared to migraineurs without aura and non-migraineurs, pointing at iron accumulation in some thalamic nuclei and at increased cellular presence in others. The observed alterations encompassed the somato-sensory, limbic and visual thalamic regions.

3655.   48 An automated approach for the quantification of brain oxygen metabolism
Peiying Liu1, Yan Cao2, Jinsoo Uh1, and Hanzhang Lu1
1Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States, 2Department of Mathematical Science, University of Texas at Dallas, Dallas, Texas, United States

CMRO2 is an important index of tissue viability and brain function. A previous study proposed an MRI technique to estimate whole-brain CMRO2 by combining non-invasive measures of CBF, arterial and venous oxygenation, which is fast and reliable. The only major obstacle of this technique before wider applications is the slice positioning of the phase-contrast MRI scans for CBF measurement requires considerable training and expertise. We developed an automatic positioning algorithm for the phase-contrast MRI based on image analysis of a time-of-flight angiogram, and thus provide a turn-key solution for the quantitative evaluation of the whole-brain CMRO2, which has minimal operator-dependence.
Electronic Poster Session - Neuro B

fMRI of Brain Disorders
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  11:00 - 12:00

  Computer #  
3656.   25 Translational BOLD fMRI in mice and man: precinical and clinical treatment approaches
Andreas Hess1, Juergen Rech2, Arnd Doerfler3, Georg Kollias4, Olaf Sporns5, and Georg Schett2
1Institute of Experimental and Clinical Pharmacology and Toxicology, FAU Erlangen-Nuremberg, Erlangen, Germany, 2Department of Internal Medicine 3, Erlangen, Germany, 3of Neuroradiology, FAU Erlangen-Nuremberg, Erlangen, Germany, 4Institute of Immunology; Alexander Fleming Biomedical Sciences Research Center, Vari, Greece, 5Department of Psychological and Brain Sciences, Programs in Neuroscience and Cognitive Science, Indiana, United States

Pain is the key symptom in patients with arthritis. We hypothesized that hypernociception due to chronic TNF overexpression leads to an altered pain processing. Using fMRI we demonstrated that mice overexpressing human tumor necrosis factor (hTNF), as well as rheumatoid arthritis patients exhibit more intensive brain activity upon nociceptive stimuli. Graph-theoretical connectivity analysis showed rewiring under chronic pain conditions i.e. tight clustering of thalamus and periaqueductal grey. Neutralization of TNF by antibodies rapidly reversed this hypernociception in mice and men. This similarity of pain related effects in mouse and man facilitates a translational approach for searching for novel analgesics.

3657.   26 Investigation of the chronic effect of streptozotocin-induced diabetes on cerebrovascular reactivity and BOLD fmri response to electrical forepaw stimulation
Edward S. Hui1, Shiliang Huang2, Yen-Yu Shih2, and Timothy Q. Duong2
1Dept of Radiology, Medical University of South Carolina, Charleston, South Carolina, United States, 2Research Imaging Institute, UTHSCSA, San Antonio, Texas, United States

Somatosensory responses to nociceptive and non-nociceptive stimuli were altered in the peripheral nervous system (PNS) of diabetic rats (first month after STZ injection) and patients. However, more evidences suggested that the central nervous system (CNS) was also involved. For instance, the evoked potential amplitude in S1 was reduced at 8 weeks of diabetes. Furthermore, a resting state fMRI, which examines neuronal connectivity, study showed impairment of the attention network to external stimuli in diabetic patientm. The goal of the current study was therefore to examine the longitudinal and chronic effect of diabetes on CNS using fMRI and CO2 challenge.

3658.   27 "Form Follows Function": Anatomic and Functional Localization of Eloquent Cortex
Mai-Lan Ho1, Rafael Rojas1, and David Hackney1
1Radiology, BIDMC, Boston, MA, United States

The purposes of this exhibit are: 1. Describe imaging signs of major cortical regions on conventional CT and MR, with attention to the central sulcus and surrounding anatomic landmarks. 2. Establish the validity of anatomic techniques for localizing eloquent cortex, based on correlation to functional MRI (fMRI) activation maps in selected case studies. 3. Identify scenarios in which technical, patient, and lesion factors may limit anatomic and/or functional characterization.

3659.   28 Effectiveness of four different clinical language paradigms for language lateralization: a ROI analysis
Domenico Zacá1, Joshua Nickerson2, Gerard Deib1, and Jay J Pillai1
1Division of Neuroradiology Johns Hopkins University School of Medicine, Baltimore, MD, United States, 2Division of Neuroradiology, The University of Vermont School of Medicine, Burlington, VT, United States

Language hemispheric dominance determined by BOLD fMRI can depend on the paradigm as well as the region of interest (ROI) considered for the lateralization index (LI) computation. In this retrospective study of 41 brain tumor patients referred for presurgical language mapping we compared the effectiveness of lateralization of four language tasks in anatomical and functional language ROIs. Two expressive tasks, rhyming and silent word generation, were the best lateralizing tasks in expressive ROIs, whereas the receptive and semantic tasks, sentence completion and listening comprehension, did not perform better than the expressive tasks for lateralization in receptive ROIs.

3660.   29 Cerebrovascular reactivity (CVR) mapping in patients with low grade gliomas undergoing presurgical mapping with BOLD fMRI
Domenico Zacá1, and Jay J Pillai1
1Division of Neuroradiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States

Angiogenesis in high grade gliomas often causes neurovascular uncoupling (NVU), making detection of eloquent cortex near these lesions difficult by BOLD fMRI. Little is known about the prevalence of NVU in low grade gliomas not characterized by angiogenesis. In this study 8 patients with low grade gliomas demonstrated ipsilesional reduced motor activation and reduced cerebrovascular reactivity (CVR) following a breath hold (BH) task compared to contralesional homologous areas. These results demonstrate the impact of NVU on presurgical BOLD fMRI activation maps in these patients and the utility of BH CVR for detection of potential NVU.

Paola Valsasina1, Maria A. Rocca2, Letizia Panicari2, Gianna Riccitelli2, Flavia Mattioli3, Ruggero Capra4, Chiara Stampatori3, Giancarlo Comi5, and Massimo Filippi1
1Neuroimaging Research Unit, Institute of Experimental Neurology, San Raffaele Scientific Institute and Vita-Salute San Raffaele University, Milan, Italy, Italy, 2Neuroimaging Research Unit, Institute of Experimental Neurology, San Raffaele Scientific Institute and Vita-Salute San Raffaele University, Milan, Italy, 3Clinical Neuropsychology Unit, Spedali Civili of Brescia, Brescia, Italy, 4Multiple Sclerosis Centre, Spedali Civili of Brescia, Brescia, Italy, 5Department of Neurology, San Raffaele Scientific Institute and Vita-Salute San Raffaele University, Milan, Italy, Italy

In this study, we used seed-voxel correlation analysis to investigate resting state (RS) functional connectivity (FC) of the anterior cingulate cortex (ACC) in two groups of patients with multiple sclerosis (MS): a treatment group, performing 12 weeks of cognitive rehabilitation of attention/information processing and executive functions, and a control group. At follow up, increased FC between the ACC, the right middle frontal gyrus and inferior parietal lobe was detected in the treated group, while decreased FC between the ACC, the cerebellum and the middle temporal gyrus was detected in the control group.

3662.   31 A Whole-Brain Network Analysis in Patients With Hereditary and Acquired Peripheral Neuropathy
Maria A. Rocca1, Paola Valsasina1, Raffaella Fazio2, Stefano Previtali2, Elisabetta Pagani1, Andrea Falini3, Giancarlo Comi2, and Massimo Filippi1
1Neuroimaging Research Unit, Institute of Experimental Neurology, San Raffaele Scientific Institute and Vita-Salute San Raffaele University, Milan, Italy, Italy, 2Department of Neurology, San Raffaele Scientific Institute and Vita-Salute San Raffaele University, Milan, Italy, Italy, 3Department of Neuroradiology, San Raffaele Scientific Institute and Vita-Salute San Raffaele University, Milan, Italy

We assessed functional connectivity (FC) at resting state (RS) in 25 patients with acquired (A) and hereditary (H) peripheral neuropathy (PN). Compared with controls, PN patients showed decreased FC in the secondary visual network and increased FC in the auditory network. Moreover, APN patients showed decreased FC in the motor, default mode and salience networks. Conversely, increased FC was found in the salience network of HPN patients. Enhanced inter-network connectivity among sensory and motor networks was found in both PN patient groups vs. controls. Such an enhancement was more evident in HPN than in APN patients.

3663.   32 Brain activation on sexual orientation in female-to-male transsexuals: A functional MR imaging study
Tae-Hoon Kim1, Seok-Kwun Kim2, and Gwang-Woo Jeong1,3
1Research Institute of Medical Imaging, Chonnam National University Medical School, Gwangju, Korea, 2Plastic and Reconstructive Surgery, Dong-A University Hospital, Busan, Korea, 3Radiology, Chonnam National University Medical School, Gwangju, Korea

Present inferences postulate that the perception of the own sex is linked to sexual differentiation of the brain and that perception in transsexuals differs from the body phenotype. Such a discrepancy is believed to be possible because sex differentiation of the brain occurs later in development than sex differentiation of genitals. Therefore, this implies that neuroanatomy plays a important role in determining transsexualism or gender identity. Recently, Gizewski et al. reported that male-to-female (MtF) transsexuals showed specific cerebral activation in response to visual erotic stimuli, indicating a tendency of female-like cerebral processing in transsexualism. However, female-to-male (FtM) transsexuals are little known. Therefore, this study was to evaluate the brain activation in response to visual erotic stimuli for cross-gender identity in FtM transsexuals by using fMRI.

3664.   33 Semantic and lexical language deficits in left temporal lobe epilepsy patients using BOLD
Senthil S Kumaran1, Kapil Chaudhary2, Manjari Tripathi2, and Sarat Chandra3
1Department of N.M.R., All India Institute of Medical Sciences, New Delhi, Delhi, India, 2Department of Neurology, All India Institute of Medical Sciences, New Delhi, Delhi, India, 3Department of NeuroSurgery, All India Institute of Medical Sciences, New Delhi, Delhi, India

Left temporal lobe epilepsy (LTLE) is a common cause of mesial temporal sclerosis (MTS) which affects the language networks. In this study we evaluated the presurgical language deficits with increasing complexity from semantic to lexical components in LTLE patients due to MTS using BOLD.

3665.   34 Functional connectivity analysis reveals disrupted interhemispheric connectivity in unilateral neocortical epilepsy
Edward J Novotny1,2, Andrew Poliakov3, Sandra Poliachik3, Seth Friedman3, Dennis Shaw3, and Jeffrey Ojemann1,4
1Pediatrics, University of Washington, Seattle, WA, United States, 2Neurology, University of Washington, Seattle, WA, United States, 3Radiology, Seattle Children's Hospital, Seattle, WA, United States, 4Neurosurgery, University of Washington, Seattle, WA

Functional connectivity MRI (fcMRI) – an analysis technique based on task-free, resting state fMRI recording -- can demonstrate disruption of connectivity in certain disease states, including epilepsy. We found that interhemispheric connectivity of resting state networks are clearly disrupted in a group of subjects being evaluated for surgical treatment of their epilepsy. These findings demonstrate that this technique may be important as part of the evaluation of subjects with epilepsy and used to investigate the relationship to surgical outcome and comorbid neuropsychological disturbances.

3666.   35 Resting State Functional Connectivity in Tuberous Sclerosis Complex and Refractory Epilepsy
Ahmad Mohamed1,2, Richard Masterton2,3, John Archer2,3, David Abbot2,3, Michael Kean4, Simon Harvey1,3, and Graeme Jackson2,3
1Department of Neurology, Royal Children's Hospital, Melbourne, Victoria, Australia, 2Brain Research Institute, Melbourne, Victoria, Australia, 3Department of Medicine, University of Melbourne, Victoria, Australia, 4Medical Imaging Department, Royal Children's Hospital, Melbourne, Victoria, Australia

This study aimed to test if functional connectivity (FC) can be used to differentiate epileptogenic from non-epileptogenic cortical tubers in four children with tuberous sclerosis complex and refractory seizures. FC was assessed using partial correlation between band-pass filtered (0.01-0.1 Hz) fMRI signal time-courses averaged within regions-of-interest placed in tubers, thalami and posterior default mode network (DMN) regions. No statistically significant difference in tuber-tuber, tuber-thalami and tuber-DMN FC was noted at either individual or group level. The few subjects, imaging under general anaesthesia and lack of simultaneous EEG recording potentially limit the study.

3667.   36 Relationship between gray matter concentration and resting functional connectivity to the thalamus: Evidence of the temporal lobe epilepsy seizure network
Martha J Holmes1,2, Zhaohua Ding1,2, Xue Yang3, Bennett A Landman2,3, John C Gore1,2, Bassel Abou-Khalil4, Hasan H Sonmezturk4, and Victoria L Morgan1,2
1Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States, 2Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States, 3Electrical Engineering, Vanderbilt University, Nashville, TN, United States, 4Neurology, Vanderbilt University, Nashville, TN, United States

Temporal lobe epilepsy (TLE) is associated with gray matter loss and changes in functional connectivity. The objective of our analysis is to examine the voxel-wise relationship between gray matter concentration (GMC) and resting state functional connectivity to the thalamus in TLE. We found the following: a cluster in the left precuneus/posterior cingulate demonstrated increased negative connectivity to the left thalamus as GMC decreased, and a cluster in the left putamen/insula displayed increased connectivity as GMC decreased in the thalamus. The changes in GMC and functional connectivity in these structures provides further evidence of their involvement in the TLE seizure network.

3668.   37 Tactile perception and Braille semantic task in late blind subjects using fMRI: understanding Braille dots and objects
Ankeeta Sharma1, Senthil S Kumaran1, and Rohit Saxena2
1Department of N.M.R., All India Institute of Medical Sciences, New Delhi, Delhi, India, 2Dr.R.P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, Delhi, India

The loss of one sensory modality results in an increased use of the remaining intact sensory systems; to improve their efficiency, and may result in cortical reorganization processes. We evaluated tactile preception in relation to language reading (using Braille input) in late blind subjects, to understand how they differentiate braille dots from the shapes and objects.

3669.   38 Mapping the different asymmetry of normal controls and first episode drug naïve schzophrenia patients by Voxel-Based Morphometry
Ling Zou1, Wei Deng2, Tao Li2, and Qiyong Gong3
1Radiology, West China Hospital,Sichuan Uiversity, Chengdu, Sichuan, China, 2psychiatry, West China Hospital,Sichuan Uiversity, 3CMRRC, Radiology Department, West China Hospital,Sichuan Uiversity

Asymmetry of two halves of brain is recognized as a fundamental property and the basis for optimal brain function division. Abnormal asymmetry that may generated in early stage of neurodevelopment was found in schizophrenia patients. However, most studies used the ROI based analysis, which resulted in the failure of exploring overall asymmetry changes. We applied optimized voxel based morphometry (VBM) study on the level of whole brain in normal controls and first-episode, antipsychotic-naive schizophrenia patients, consequently observed overall lateralization patterns and their decease and aberrance in schizophrenia patients. Future study is necessary to gain further insight into our findings.

3670.   39 Atypical auditory-visual integration mechanism in Borderline Personality Disorder: A fMRI analysis using emotional congruence and incongruence in music and facial images
Jeong-Won Jeong1, Jeffrey G Kuentzel2, Vibhav A Diwadkar3, Carla D Chugani4, Varun Shandal5, Harry T Chugani6, and Diane C Chugani7
1Pediatrics and Neurology, Wayne State University, Detroit, MI, United States, 2Psychology, Wayne State University, 3Behavioral Neuroscience, Wayne State University, 4Counseling and Psychological Services, Florida Gulf Coast University, 5PET center, Wayne State University, 6Pediatrics, Neurology, and Radiology, Wayne State University, 7Pediatrics and Radiology, Wayne State University

Borderline personality disorder (BPD) is a prevalent mental illness characterized by pervasive instability in emotion, interpersonal relationships, self-image, and behavior. The hallmark features of BPD are affective instability and severe mood swings but there have been few functional imaging studies to investigate neuronal substrates underlying these features in BPD patients. Our previous fMRI study reported that there were significant Blood Oxygen Level Dependent (BOLD) signal increases in the superior temporal gyrus (STG) and fusiform gyrus (FG) of healthy young adults, which respond to emotionally congruent and incongruent music-face images, respectively. We presume that these BOLD gains in STG and FG underlie emotion perception that responds to emotional congruence in multi-modal sensory inputs. This study extends our fMRI technique to examine how STG and FG of BPD patients respond to emotionally paired music-face images, which might provide a mechanism related to elevated response to emotional stimuli.

3671.   40 Altered Cerebral Effective Connectivity in Theory-of-Mind in Autism Spectrum Disorders
Karthik Ramakrishnan Sreenivasan1, Gopikrishna Deshpande1,2, Hrishikesh Deshpande3, and Rajesh K Kana4
1AU MRI Research Center,Department of Electrical and Computer Engineering, Auburn University, Auburn, Alabama, United States, 2Department of Psychology, Auburn University, Auburn, Alabama, United States, 3Department of Biomedical Engineering, University of Alabama, Birmingham, Alabama, United States, 4Department of Psychology, University of Alabama, Birmingham, Alabama, United States

The current study focuses on effective brain connectivity in an fMRI study of Theory-of-Mind (ToM) in high-functioning adults with autism. fMRI time series were first deconvolved with cubature Kalman filter and then the underlying neuronal states subsequently input to a multivariate autoregressive model for finding effective connectivity paths. The results showed that connectivity between ToM regions was greater in control as compared to Autism and those paths mediated the relationship between subject category (control/autism) and behavioral metrics such as Autism Quotient and Mind in the Eyes score.

3672.   41 Disturbed Brain Complex Network in Attention-Deficit/Hyperactivity Disorder
Meilin Liang1, Pan Lin1, Ming Zhang2, Chengyu Li1, Xin Liu1, Chenwang Jin2, and Chen Niu2
1Key Laboratory of Biomedical Information Engineering of Education Ministry, Xian Jiaotong University, Xi'an, Shaanxi, China, 2Department of Medical Imaging, the First Affiliated Hospital of Medical College,Xian Jiaotong University, Xi'an, Shaanxi, China

Attention-deficit/hyperactivity disorder (ADHD) is a commonly observed neurobehavioral disorders of childhood, but its pathogenic mechanism is still unclear. The graph theory deals with the whole brain as a complex network that owns its unique topological properties. It supplies a novel insight into the investigating of human brain network to find how ADHD affect the brain function. The purpose of this study was to investigate the topological properties of complex network in ADHD, and find the disturbed connectivity regions of ADHD patients¡¯ brain using graph theory.

3673.   42 Altered Default Mode Network Functional Connectivity in Amyotrophic Lateral Sclerosis
Pan Lin1, Ming Zhang2, Chenwang Jin2, Cuiping Mao2, Chen Niu2, Xin Liu1, Zhigang Min2, Qiaoting Jin3, and Jingxia Dang3
1Key Laboratory of Biomedical Information Engineering of Education Ministry,Xi'an Jiaotong University, Xi'an, Shannxi, China, 2Department of Medical Imaging, the First Affiliated Hospital of Medical College,Xian Jiaotong University, Xi'an, Shaanxi, China, 3Department of Neurology, the First Affiliated Hospital of Xian Jiaotong University, Xi'an, Shaanxi, China

Characterization of the default mode network as a complex network of functionally interacting dynamic systems has received great interest for clinical application. ALS is a progresssive disease that is associated with motor disorder. Little is know about how ALS affects the defualt mode network. The aim of this study is to assess the complex network of DMN while in the resting state, which can provide greated insight into how DMN functional networks are affected by ALS.

3674.   43 Evaluation of auditory processing in blind people: a comparison of semantic and auditory perception
Ankeeta Sharma1, Senthil S Kumaran1, and Rohit Saxena2
1Department of N.M.R., All India Institute of Medical Sciences, New Delhi, Delhi, India, 2Dr.R.P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, Delhi, India

Blind Children show altered brain activity in early visual cortex and develop their hearing better to compensate the loss of vision. We evaluated BOLD activity due to sounds, orientation and semantic processing through auditory cues in late blind subjects. Auditory and perception discrimination showed cross-modal activity in visual cortex, suggesting that reorganization may be limited to perception and less affected by attention.

3675.   44 Functional MRI of Working Memory in Patients of Mild Traumatic Brain Injury
Yen-Peng Liao1, Chi-Jen Chen1, Chih-Hsiung Wu2, Hui-Ling Hsu1, Ying-Chi Tseng1, Ho-Ling Liu3, and Wen-Ta Chiu4
1Department of Medical Imaging, Taipei Medical University - Shuang Ho Hospital, New Taipei City, Taiwan, Taiwan, 2Surgery, Taipei Medical University - Shuang Ho Hospital, New Taipei City, Taiwan, Taiwan, 3Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan County, Taiwan, Taiwan, 4Graduate Institute of Injury Prevention and Control, Taipei Medical University, Taipei City, Taiwan

Previous functional MRI studies of mild traumatic brain injury (MTBI) patients have indeed shown altered patterns of activation during working memory (WM) task. However, the results were inconsistent. This study aimed to analyze the brain activation patterns in response to n-back WM loads after MTBI. The results showed that MTBI-induced differences in WM functional activity were observed in the absence of differences in neuropsychological performance, suggesting that this approach may increase sensitivity to MTBI compared with neuropsychological evaluation alone. The results also lend further evidence to the potential for cerebral plasticity to maintain performance levels on WM tasks after MTBI.

3676.   45 Withdrawn


3677.   46 Defrosting Parkinson’s disease: exploring the neural correlates of freezing of gait.
James M Shine1, Philip Ward2, Elie Matar1, Sharon Naismith1, and Simon Lewis1
1Brain and Mind Research Institute, The University of Sydney, Sydney, NSW, Australia, 2School of Psychiatry, The University of New South Wales

Freezing of gait (FOG) is a devastating symptom of advanced Parkinson’s disease in which patients suddenly feel as though their feet have become “stuck to the ground”. Despite a well-characterised clinical phenotype, the condition remains poorly understood. To remedy this, we have combined fMRI with a novel virtual reality walking paradigm, allowing the safe recreation of freezing of gait episodes and the subsequent exploration of the neural correlates of these episodes. In a cohort of 16 patients, we found robust patterns of activation that were consistent with the predictions of a recently-proposed model.

3678.   47 Brain activation patterns and brain volume changes associated with explicit retrieval of unpleasant and neutral words in patients with obsessive compulsive disorder
Shin-Eui Park1, Gwang-Won Kim2, Jong-Chul Yang3, Gyung-Ho Jeong4, Heoung-Keun Kang2, and Gwang-Woo Jeong1,2
1Interdisciplinary Program of Biomedical Engineering, Chonnam National University, Gwang Ju, Korea, 2Radiology, Chonnam National University Medical School, Gwang Ju, Korea, 3psychiatry, Chonbuk national University medical school, 4Radiology, Chonbuk national University Medical school

Obsessive compulsive disorder (OCD) is an anxiety disorder characterized by intrusive thoughts that produce uneasiness, apprehension, fear, or worry, by repetitive behaviors aimed at reducing the associated anxiety, or by a combination of such obsessions and compulsions so the author attempts to investigate about explicit memory of Obsessive compulsive disorder
Electronic Poster Session - Neuro B

Head & Neck Imaging
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  10:00 - 11:00

  Computer #  
3679.   49 Contributions of in-plane CSF flow to the derivation of intracranial compliance: a three-direction cine phase-contrast flow study.
Yi-Ying Wu1,2, Yu-Wei Tang3, Hsu-Hsia Peng4, Cheng-Wen Ko5, Cheng-Wen Ko5,6, Hsiao-Wen Chung7,8, and Teng-Yi Huang3
1Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei,Taiwan, Taiwan, 2National Taiwan University, Taipei,Taiwan, Taiwan, Taiwan, 3National Taiwan University of Science and Technology, 4National Tsing Hua University, 5Computer Science and Engineering, National Sun Yat-Sen University, 6National Sun Yat-Sen University, 7Biomedical Electronics and Bioinformatics, National Taiwan University, 8National Taiwan University

Previous studies have proposed noninvasive phase-contrast flow mapping magnetic resonance imaging method to estimate ICC based on blood/CSF flow rates and CSF pressure gradient. Assuming that the CSF flow direction is mainly caudocranial in the spinal canal at the measurement sites, the phase-contrast technique needs to be applied with only one velocity encoding direction, which greatly shortens the scan time. In this study, we attempted to verify this assumption by using three-direction measurements to examine the contributions of various terms that might cause estimation inaccuracies in MR imaging-based ICC measurements.

3680.   50 Estimation of perilymph enhancement after intrarympanic administration of Gd-DTPA by fast T1-mapping with dual flip angle 3D-spoiled gradient echo sequence
Shinji Naganawa1, Masahiro Yamazaki1, Hisashi Kawai1, and Tsutomu Nakashima2
1Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan, 2Department of Otorhynolaryngology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan

FT1 mapping by 3D-GRE can predict poor enhancement of inner ear after intratympanic Gd injection, therefore unnecessary long MR scans can be avoided.

3681.   51 Signal intensity changes of the cochlea in patients with cerebellopontine meningioma on isotropic 3D fluid-attenuated inversion recovery MR imaging at 3 T; comparison with vestibular schwannoma
Jin Wook Choi1, Hyung-Jin Kim1, Sung Tae Kim1, Pyoung Jeon1, Keon Ha Kim1, and Hong Sik Byun1
1Radiology, Samsung Medical Center, Kangnamgu, Seoul, Korea

The signal intensity (SI) of the labyrinth in patients with vestibular schwannoma (VS) is known to be increased on FLAIR MRI due to increased protein concentration within the perilymph. We compared SI changes of the cochlear in patients with cerebellopontine angle (CPA) meningioma with VS on 3D FLAIR imaging. The SIs of the cochlear in patients with CPA/IAC meningioma are significantly lower than those in patients with VS on 3D FLAIR imaging. There may exist more complex mechanisms other than mechanical obstruction of the IAC to explain the cause of increased protein concentration in the perilymph in patients with VS.

3682.   52 Kinetic Analysis of DCE-MRI in Head and Neck by Using the Dynamic Tracer Concentration in Jugular Veins
Jing Yuan1, Steven Kwok Keung Chow1, David Ka Wai Yeung1, Anil T Ahuja1, and Ann D King1
1Imaging and Interventional Radiology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong

Dynamic tracer concentration in veins, although as blood collecting vessels, was proposed as a mathematical input function for head and neck DCE-MRI kinetic analysis to compensate for the arterial blood in-flow effect. The tracer concentration in veins and arteries should be theoretically equal in a single-pool and low-permeability model. Dynamic concentration-time-curves (CTCs) in arteries and veins were used for Tofts parameter estimation. Remarkable inter-slice concentration differences were found in arteries and resulted in considerable parameter estimation inconsistency. As comparison, the in-flow effect was significantly reduced and consistent kinetic parameter estimation was achieved by using the venous CTCs.

3683.   53 Efficacy of diffusion-weighted MR imaging and PET/CT for predicting tumor response to chemoradiation therapy in squamous cell carcinoma of head and neck
Munetaka Matoba1, Yasuaki Kuginuki1, Ichiro Toyoda1, Naoto Watanabe1, and Hisao Tonami1
1radiology, kanazawa medical university, daigaku 1-1, Ishikawa, Japan

Purpose : To evaluate the efficacy of ADC and SUV for prediction of treatment response to chemoradiotherapy in squamous cell carcinoma of head and neck. Methods : DWI was performed before treatment, and 3 weeks after the start of treatment (3w-Tx). PET/CT was performed before treatment. The relationship between the RECIST and imaging parameters was examined. Results : The change in ADC within 3w-Tx and SUV significantly correlated with the tumor decrease. The CR group showed significantly higher increase in ADC of 3w-Tx than the PR group. Conclusion : ADC and SUV may be used for prediction of tumor response.

3684.   54 Non-Gaussian Analysis of Diffusion-Weighted Imaging in Nasopharyngeal Carcinoma at 3T
Jing Yuan1, Steven Kwok Keung Chow1, David Ka Wai Yeung1, Yujia Li1, Anil T Ahuja1, and Ann D King1
1Imaging and Interventional Radiology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong

This pilot study is to investigate the feasibility of non-Gaussian diffusion models, including diffusion kurtosis imaging (DKI), stretched exponential model (SEM), intravoxel incoherent motion (IVIM) and statistical model, for 3T diffusion-weighted imaging (DWI) analysis in patients with nasopharyngeal carcinoma (NPC). The results showed that at an extended b-value range up to 1500s/mm2, all non-Gaussian models yielded better diffusion signal fitting than the normal mono-exponential model for both primary tumors and metastatic nodes. Additional to the nominal diffusion coefficient, other non-Gaussian parameters could be extracted as potential biomarkers for NPC lesion detection and characterization in clinical applications.

3685.   55 Utility of high-resolution readout-segmented diffusion weighted imaging of the parotid gland
Shigeaki Umeoka1, Nobuko Morisawa1, Masako Kataoka1, David Andrew Porter2, and Kaori Togashi1
1Diagnostic Imaing & Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Kyoto, Japan, 2Siemens AG, Erlangen, Germany

Read-out segmented echo-planar imaging (RS-EPI) combined with 2D-navigator-based reacquision has been recently established with high resolution with distortion-free, reduced susceptibility artifact and blurring from T2* signal decay compared to conventional single-shot EPI (SS-EPI). RS-EPI DWI of the central neural system has been documented to improve image quality. In our study, RS-EPI DWI could reduce susceptibility artifact and provide better delineation and visualization of internal structure of the parotid gland. Although further improvement might be necessary to shorten the scan time, this newly-developed RS-EPI MRI could be a promising tool to visualize and evaluate the head & neck organs.

3686.   56 MR Elastography of Salivary Gland Masses: Preliminary Results
Kunwar Bhatia1, Philippe Garteiser2, Ralph Sinkus2, David Yeung3, Jing Yuan1, Yolanda Lee3, Ann King1, and Anil Ahuja1
1Imaging and Interventional Radiology, Chinese University of Hong Kong, Shatin, N.T., Hong Kong, 2Department of Radiology and INSERM U773,3Imaging and Interventional Radiology, Prince of Wales Hospital, Shatin, N.T., Hong Kong

Problem: Conventional imaging has suboptimal diagnostic accuracy for salivary masses. Methods: A study of MR elastography was conducted in nine patients with cytologically-confirmed salivary tumours using a customized mechanical driver and gradient echo MR sequences with fractional motion encoding. Recovered shear moduli (|G*| stiffness) for tumours and normal contralateral glands (controls) were compared using t-tests. Results: Pooled data of |G*| in tumours (0.83±0.47 kPa) overlapped with controls (0.59±0.32 kPa)(p=0.23). However, ratios of |G*|tumour:|G*|control for individual patients exceeded 1 in 8/9 cases (1.41±0.37, p=0.01). Conclusion: Preliminary results suggests that normalized shear moduli on MRE may differentiate salivary tumours from normal glands.

3687.   57 Real-time MRI of Speaking: Preliminary Experience at a Temporal Resolution of 33ms
Aaron Niebergall1, Shuo Zhang1, Martin Uecker1,2, and Jens Frahm1
1Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut fuer biophysikalische Chemie, Goettingen, Germany, 2Electrical Engineering and Computer Science, University of California, Berkeley, California, United States

Previous dynamic studies of speaking mechanism using MRI suffer mainly from susceptibility artifacts and insufficient temporal resolution. Here, we applied the recently introduced real-time MRI technique based on radial FLASH acquisition and nonlinear inverse reconstruction. Typical images had an in-plane resolution of 1.5 mm and acquisition times of 33 ms (30 fps), and are free from susceptibility or motion artifacts. The movies successfully resolved the rapid and coordinated movements of the main articulators such as the lips, tongue, velum and vocal folds, during production of vowels, consonants, words and sentences. It thus promises a useful tool to study speech production.

58 Measurement of upper airway compliance using dynamic MRI
Yoon-Chul Kim1, Ximing Wang2, Winston Tran2, Michael C.K. Khoo2, and Krishna S. Nayak1
1Electrical Engineering, University of Southern California, Los Angeles, CA, United States, 2Biomedical Engineering, University of Southern California, Los Angeles, CA, United States

In research studies of obstructive sleep apnea, upper airway (UA) compliance (related to the amount of change in UA cross-sectional area per unit pressure) is a measure of airway collapsibility. Fiberoptic endoscopy is used to measure the area but is invasive. We present a new MR imaging protocol that simultaneously acquires dynamic airway images and physiological signals and is compatible with an external airway occlusion setup. UA compliance was measured after synchronization of the UA area and mask pressure dynamics. The measurements in two volunteers during wakefulness suggest that the velopharyngeal site is likely to collapse first over the oropharyngeal site.

3689.   59 Simulation of Nasal Air Flow from High Resolution MRI Images of Patients with Empty Nose Syndrome
Arthur Wunderlich1, Marc Scheithauer2, Fabian Sommer2, and Wolfgang Freund1
1Diagnostic and Interventional Radiology, Univ.-Clinic Ulm, Ulm, Germany, 2ENT Dept., Univ.-Clinic Ulm, Ulm, Germany

To study the nasal air flow with finite volume methods, we investigated ten patients with high-resolution MRI during breathing of a) room air, b) menthol and c) after inhalation of the decongestant xylometazoline. Nose cavities were segmented from MRI data and flow was simulated with mathematical methods. Results were compared to those of a healthy control. Simulations show the flow distribution in the nasal cavities and its dependence on medication. In patients, flow is divided nearly equal between both nasal cavities, in contradiction to the physiological flow pattern observed in controls where one nose cavity manages most of the flow.

3690.   60 DCE-MRI for Assessing Antiangiogenic Drug Effect in a Mouse with Choroidal Neovascularization
Jae-Hun Kim1, Ji Hoon Cha1, Geun Ho Im2, Julius Chung3, and Jung Hee Lee1
1Department of Radiology, Sungkyunkwan University School of Medicine, Seoul, Korea, 2Center for Molecular and Cellular Imaging, Samsung Biomedical Research Institute, 3Samsung Advanced Institute for Health Sciences & Technology, Sungkyunkwan University

Dynamic contrast-enhanced magnetic resonance imaging provides parameters indicating permeability of tumor microvessels which has been shown to be closely related to angiogenesis. In this study, we tested that DCE-MRI can provide a non-invasive imaging biomarker to evaluate anti-angiogenic efficacy of macular degeneration. Our results demonstrated that there were significant changes between permeability parameters computed from drug treated and control group at 14 days (P < 0.01). These findings show the feasibility of permeability parameter as noninvasive biomarker for antiangiogenic drug evaluation in a mouse with choroidal neovascularization

3691.   61 Determination of T1-Dependence on Oxygenation in the Eye Using a Simple Phantom Model
Nicholas G Dowell1, Edward H Hughes2, Andrew Simpson2, and Paul S Tofts1
1Brighton and Sussex Medical School, Brighton, United Kingdom, 2Sussex Eye Hospital, Brighton, United Kingdom

The relaxation parameter T1 has a dependence on the partial pressure of O2 (pO2), since T1 is reduced by the presence of paramagnetic O2. Here we discuss the construction of a pO2 phantom that can be used to precisely determine this T1 dependence on pO2, with the intention of performing precise measures of oxygenation in the vitreous humour (the clear gel between the lens and the retina) in the eye. We present the relation between pO2 and T1 for balanced salt solution (BSS), which is used as a replacement for the extracted vitreous humour following a vitrectomy.

3692.   62 Vitreous Oxygenation Measured by T1 mapping in the Eye Reveals No Increased Oxygenation Following Vitrectomy
Nicholas G Dowell1, Edward H Hughes2, Andrew Simpson2, and Paul S Tofts1
1Brighton and Sussex Medical School, Brighton, United Kingdom, 2Sussex Eye Hospital, Brighton, United Kingdom

We use a T1 mapping technique to determine the partial pressure of oxygen (pO2) of the vitreous humour (the clear gel that fills the eyeball between the lens and the retina) in a group of patients undergoing a vitrectomy (the extraction of the vitreous). We measured pO2 in 9 patients before and after vitrectomy and showed that there was no increase in vitreous oxygenation. This finding could have implications for the understanding of the therapeutic benefits of vitrectomy and may help improve patient treatment. The technique itself provides a non-invasive approach to pO2 measurement that will permit longitudinal studies of the oxygenation mechanism of the eye.

3693.   63 Age-Related Changes of Bone Marrow in the Mandible with Quantitative MRI
Kotaro Sekiya1,2, Osamu Sakai1, Memi Watanabe1, Rohini N. Nadgir1, Joseph H. Liao1, Shun Sakai1, Takashi Kaneda3, and Hernan Jara1
1Boston Medical Center, Boston University School of Medicine, Boston, MA, United States, 2Nihon University Graduate School of Dentistry at Matsudo, Matsudo, Chiba, Japan, 3Department of Radiology, Nihon University School of Dentistry at Matsudo, Matsudo, Chiba, Japan

Purpose: To investigate age-related changes of bone marrow in the mandible using quantitative MRI. Methods: 36 subjects were imaged using the mixed-TSE sequence at 1.5T. The mandible was manually segmented, and further divided into 5 regions. T1 and T2 relaxation time histograms and volumes of the entire mandible and 5 sub-segments were analyzed. Results: T1 and T2 histograms demonstrated expected age-related yellow marrow conversion. Conclusion: Expected progression of marrow change in the mandible by visual estimates is confirmed quantitatively; such quantitative analysis may prove useful in detecting subtle marrow abnormalities prior to becoming visually apparent.

3694.   64 Comparative Study of a Professional Tenor in a Tilting MR-Scanner - Does Supine Position Change the Configuration of the Vocal Tract?
Michael Burdumy1,2, Louisa Traser2, Marco Vicari1,3, Matthias Weigel1, Bernhard Richter2, Jürgen Hennig1, Maxim Zaitsev1, and Matthias Echternach2
1Department of Radiology, Medical Physics, University Medical Center Freiburg, Freiburg, Germany, 2Department of Musicians' Medicine, University Medical Center Freiburg, Freiburg, Germany, 3Esaote S.p.a., Genoa, Italy

Only recently MR Imaging has been used to investigate movement patterns in the vocal tract during singing. In our study we compare structures of the vocal tract of a professional tenor while either in supine or prone position using a tilting 0.25T MR-Scanner. The tenor was instructed to sing an ascending scale in both supine and prone position. Then, distances between anatomical landmarks were measured in the acquired sagittal images. Our results indicate only minor differences in these distances in respect to posture.

3695.   65 In vivo pre-operative magnetisation transfer ratio for detection of thyroid malignancy
Sidhartha Nagala1, Mary McLean2, Piyush Jani1, and John Griffiths2
1Otolaryngology, Addenbrooke's Hospital, Cambridge, United Kingdom, 2Cambridge Research Institute, Cancer Research UK, Cambridge, United Kingdom

A demand for new screening tests to discriminate between different thyroid tumors exists. One ex vivo study utilized magnetization transfer ratios to differentiate between normal thyroid, benign and malignant thyroid tumors. In this work, we present the results of the first in vivo study in five normal volunteers and 25 patients with suspected thyroid tumors, prior to surgery. The sensitivity and specificity to discriminate between benign and malignant thyroid tumors using this technique were comparable to the current gold standard, ultrasound-guided needle biopsy. It has potential future clinical use, and maybe valuable when combined with other imaging techniques.
Electronic Poster Session - Neuro B

Clinical Diffusion & Microstructure
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  11:00 - 12:00

  Computer #  
3696.   49 VBM study of Diurnal Variations of Brain Diffusion in Healthy Adults
Chunxiang Jiang1, Lijuan Zhang*1, Xiaojing Long1, Weiqi Liao1, and Wenhui Huang1
1Shenzhen Institutes of Advanced Technology,Chinese Academy of Sciences, Shenzhen, Guangdong, China

Diurnal alteration of diffusion parameters were observed in grey and subgyral white matter of healthy human brain. Peak ADC changes were found to locate in bilateral occipital lingual and calcarine regions while peak FA changes were located in the frontal lobes. Changes in brain diffusion parameters may reflect the underlying circadian physiological variations of human brain.

3697.   50 The Voxel-Based Comparison of Fractional Anisotropy and Mean Diffusivity between the Elderly and Young Using TBSS
Fan-Pei Gloria Yang1, Yao-Chia Shih2,3, Ming-Chieh Mindy Fang1, Kayako Matsuo3, Shen-Hsing Annabel Chen4, Toshiharu Nakai5, and Wen-Yih Issac Tseng3,6
1Department of Foreign Languages and Literature, National Tsing Hua University, Hsinchu, Taiwan, 2Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan, 3Center for Optoelectronic Biomedicine, National Taiwan University College of Medicine, Taipei, Taiwan, 4Division of Psychology, School of Humanities and Social Sciences, Nanyang Technological University, Singapore, Singapore, 5National Center for Geriatrics and Gerontology, Aichi, Japan, 6Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan

Age related decreases in fractional anisotropy (FA) and increases in mean diffusivity (MD) were observed across the entire white matter (WM) skeleton as well as in specific WM tracts. In this study, TBSS was applied to FA and MD images to examine the differences in WM integrity between healthy elderly and young participants. The efficient registration by TBSS successfully demonstrated the differences between healthy young and elderly groups. FA and MD shared the most significant difference in corona radiata. In conclusion, the findings demonstrate the effectiveness of TBSS as a population-wise measure of the WM change on a voxel-by-voxel basis.

3698.   51 High-resolution diffusion tensor imaging of the hippocampus: a comparative study of multi-shot vs. single-shot acquisitions
Ryo Sakamoto1, Tomohisa Okada1, Koji Sakai2, Akira Yamamoto1, Mitsunori Kanagaki1, Seiko Kasahara1, Emiko Morimoto1, Takeshi Sawada1, Thorsten Feiweier3, David Andrew Porter3, and Kaori Togashi1
1Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan, 2Department of Human Health Science, Kyoto University Graduate School of Medicine, Kyoto, Japan, 3Siemens AG, Erlangen, Germany

High-resolution DTI with reasonable reproducibility in acceptable scan time for the hippocampus and structures at its vicinity are highly important for detection of faint pathological changes of neurological disorders. Both of two latest high-resolution DTI sequences, single-shot Advanced (Adv)-DTI using a single refocusing RF with distortion correction and multi-shot readout segmented (RS)-DTI, showed high reproducibility of ADC. RS-DTI had less distortion and was considered more accurate for population-based analysis. For FA, Adv-DTI was superior, probably due to higher SNR. In either case, CSF had much higher variance and it had better be excluded from further analysis such as voxel-based morphometry.

3699.   52 In-vivo Detection of Intracortical Myelinated Fibers in Human Hippocampal Formation: Submillimeter Resolution Diffusion Tensor Imaging Compared with Histological Findings
Takashi Yoshiura1, Akio Hiwatashi1, Satoshi Suzuki2, Tsuyoshi Okamoto3, Osamu Togao1, Koji Yamashita1, Kazufumi Kikuchi1, and Hiroshi Honda1
1Department of Clinical Radiology, Kyushu University, Fukuoka, Japan, 2Department of Neuropathology, Kyushu University, Fukuoka, Japan, 3Department of Advanced Medical Initiatives, Kyusuh University, Fukuoka, Japan

Intracortical myelinated fiber (ICMF) is an essential component to characterize microarchitecture of the cerebral cortex. Our purpose was to test the feasibility of in-vivo detection of ICMF in the human hippocampal formation by high-resolution diffusion tensor (DT) imaging. DT images of the hippocampal formation were obtained with an in-plane resolution of 0.85 mm. Fractional anisotropy (FA) in 3 different cortical subregions were compared. FA in subiculum was significantly higher than those in the other regions, which was in accordance with histological findings in myelin-stained specimens. Results suggested that in-vivo detection of ICMF using high resolution DT imaging is feasible.

3700.   53 The application of multiple b-value DWI with a stretched-exponential model in preoperative grading of cerebral gliomas
Wen-zhen Zhu1, and He Wang2
1Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China, 2Applied Science Lab, GE Healthcare

The diffusion attenuation of brain water does not follow monoexponential decay and will deviate from straightness when b-factor exceed 1000 s/mm². The purpose of this study was to evaluate the application value of multiple b-value DWI with stretched- exponential model in grading of astrocytomas.The results demonsttrated that the quantitative parameters (DCC and ) of stretched exponential model multi-b DWI provides a more accurate estimate in the preoperative grading of gliomas than ADC of the standard mono-exponential model DWI, which can be new imaging markers to differentiate the grade of gliomas and evaluate the effectiveness of therapy.

3701.   54 On using structural network patterns for prediction of genetic risks in Schizophrenia
Madhura A Ingalhalikar1, Luke Bloy1, Drew Parker1, Raquel Gur2, Ruben Gur2, and Ragini Verma1
1Section of Biomedical Image Analysis, University of Pennsylvania, Philadelphia, Pennsylvania, United States, 2Brain Behavior Laboratory, University of Pennsylvania, Philadelphia, Pennsylvania, United States

This study investigates the presence of endophenotypic brain patterns in the family members of patients with schizophrenia via a structural network analysis. High dimensional gender specific classifiers based on local and global network properties were constructed for patients diagnosed with schizophrenia or schizoaffective disorder and healthy controls. The classifier associated a distributed network connectivity score (DNCS) with each of the asymptomatic family member. Forty percent of the FM’s were classified closer to patients. Furthermore, females displayed enhanced genetic susceptibility based on the specificity of the classifier and the DNCS scores of the family members.

3702.   55 Principal Diffusion Direction in Relation to the Geometry of the Cortical Surface in Multiple Sclerosis
Elisabetta Pagani1, Maria A. Rocca1, Paolo Preziosa1, Sarlota Mesaros2, Bruno Colombo3, Mark A. Horsfield4, Andrea Falini5, Giancarlo Comi3, and Massimo Filippi1
1Neuroimaging Research Unit, Institute of Experimental Neurology, San Raffaele Scientific Institute and Vita-Salute San Raffaele University, Milan, Italy, Italy, 2Clinic of Neurology, Faculty of Medicine, University of Belgrade, Belgrade, Yugoslavia, 3Department of Neurology, San Raffaele Scientific Institute and Vita-Salute San Raffaele University, Milan, Italy, Italy, 4Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom,5Department of Neuroradiology, San Raffaele Scientific Institute and Vita-Salute San Raffaele University, Milan, Italy, Italy

In 113 multiple sclerosis (MS) patients and 35 healthy subjects, we calculated the angle between the principal diffusion direction and the cortical surface within each voxel of the brain cortex. It has previously been suggested that, in normal mature GM no preferential direction for diffusion exists, because of the cellular structures components that run both parallel (dendrites) and perpendicular (neurons and neuritis) to the cortex. MS patients (particularly those with the progressive disease clinical phenotypes) had an increased number of GM voxels with an angle close to 90 degrees, suggesting a degeneration of the structures running perpendicular to the cortical surface.

3703.   56 Microstructural Abnormalities in the Corpus Callosum of Patients with Pelizaeus-Merzbacher Disease with Different PLP1 Mutations.
Malek I Makki1, Jeremy Laukka2,3, and James Garbern4
1MRI Research, University Children Hospital Zurich, Zurich, Switzerland, 2Radiology and Neurology, Michigan State University, East Lansing, Mi, United States, 3Neurology, Wayne State University, Detroit, Mi, United States, 4Molecular Medicine and Genetics, Wayne State University, Detroit, Mi, United States

DTI was performed on twelve patients with Pelizaeus-Merzbacher disease. These had different PLP1 mutation categories: null, moderate, and severe. Patients with moderate mutation exhibited the lowest radial diffusion and ADC and the highest FA in the splenium. This suggested hypomyelination and axonopathy. We also observed significant differences in radial diffusion and anisotropy between moderate and null mutations in the splenium showing that these patients have mild reduction in myelin with generally preserved axons.

3704.   57 A comparison of HARDI and restricted diffusion q-space imaging for assessment of auditory nerve integrity
David K. Wright1,2, David B. Grayden3, Jhodie R. Duncan1, and Leigh A. Johnston1,3
1Florey Neuroscience Institutes, Parkville, Victoria, Australia, 2Centre for Neuroscience, University of Melbourne, Melbourne, Victoria, Australia,3NeuroEngineering Laboratory, Electrical and Electronic Engineering, University of Melbourne

Cochlear implants have been remarkably successful in providing hearing to the profoundly deaf, however there is great variability in the benefit that individual cochlear implant users experience. It is accepted that the condition of the auditory nerve correlates with implant success. To date, diffusion imaging studies have focused on higher auditory pathways rather than assessing the auditory nerve itself. As such, we assess high angular resolution diffusion imaging and q-space approaches in ex vivo rat cochlea, with the aim of developing a clinical tool to predict the viability of cochlea implantation prior to surgery.

3705.   58 Unilateral Sensorineural Hearing Loss in Children is Predicted by Reduced Mean Diffusivity in the Sublenticular Region of the Left Internal Capsule
Vincent J Schmithorst1, Scott K Holland2, and Robert W Keith3
1Radiology, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA, United States, 2Children's Hospital, Pediatric Neuroimaging Research Consortium, Cincinnati, OH, United States, 3Audiology, University of Cincinnati, Cincinnati, OH, United States

Diffusion tensor imaging (DTI) and multi-voxel pattern analysis (MVPA) were performed on normal-hearing children and children with unilateral sensorineural hearing loss (USNHL). USNHL was predicted by reduced mean diffusivity (MD) in the sublenticular part of the left internal capsule, and the reduced MD was the result of decreased radial diffusivity (RD). Our results likely indicate activity-dependent changes in myelination in children with USNHL in the final part of the auditory pathway in the left hemisphere. The decreased MD did not correlate with higher-order auditory performance, indicating a likely cortical etiology for these deficits in children with USNHL.

3706.   59 Alterations of the inferior longitudinal fasciculus in congenital and late blindness
Nina L. Reislev1,2, Maurice Ptito1,3, Ron Kupers2, Hartwig R. Siebner1,2, and Tim B. Dyrby1
1Danish Research Center for Magnetic Resonance, section 340, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark, 2Department for Neuroscience and Pharmacology, Faculty of Health Sciences, Copenhagen University, Copenhagen, Denmark, 3Université de Montréal, School of Optometry, Montréal, Québec, Canada

This study examines the effect of the functional reorganization in the visually deprived human brain on the underlying white matter microstructure. White matter changes were examined in the inferior longitudinal fasciculus (ILF) that belongs to the ventral visual pathway. Diffusion weighted MRI was acquired in 6 congenitally blind, 6 late blind, and 6 matched sighted controls. Left and right ILF were extracted from deterministic tractography. Diffusion parameters related to microstructural properties were determined. We found that compared to control subjects, congenitally blind and late blind subjects had significantly lower fractional anisotropy of ILF.

3707.   60 VEGF enhance the permeability of the blood-brain barrier
Shize Jiang1, Rui Xia1, Lei Wang1, and Fabao Gao1
1Department of Radiology, Molecular Imaging Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China

The blood-brain barrier (BBB) is one of the most important interfaces that keep the homeostasis of brain. However, it also prevents drugs from entering in morbid state. VEGF is an important growth factor that promotes neovascularization. We think it might be helpful to increase the permeability of the BBB. To test this hypothesis, we used KM mice with the venous injection of Hu-VEGF165 and detect the permeability of the BBB both in MRI and histological methods. We find that VEGF can increase the permeability of the BBB and may be a new direction for the CNS drugs delivery.

3708.   61 Brain core temperature of mild head trauma patients as assessed by DWI
Jun Tazoe1, Kei Yamada1, Koji Sakai2, and Kentaro Akazawa1
1Radiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Kyoto, Japan, 2Human Health Science, Graduate School of Medicine, Kyoto University, Kyoto, Kyoto, Japan

Brain temperature is known to increase in severe head trauma patients. In mild head trauma cases, however, temperature measurement is not possible and the alteration in brain temperature has not been assessed. We tried assessing their cerebral ventricular temperature by DWI. 20 patients of within-30-day from mild head trauma were compared with the normal controls (14 subjects). 4 patients at the over-30-day period were compared to other groups. In our study, the temperature difference was found statistically significant when within-30-day and normal controls were compared. This decrease in temperature was considered to be the reflection of decline in metabolism.

3709.   62 Posttraumatic white matter diffusivity changes in postmortem brain
Nikolaus Krebs1,2, Christian Langkammer3, Stefan Ropele3, Franz Fazekas3, Walter Goessler4, Kathrin Yen5, and Eva Scheurer1,2
1Ludwig Boltzmann Institute for Clinical-Forensic Imaging, Graz, Austria, 2Medical University, Graz, Austria, 3Department of Neurology, Medical University, Graz, Austria, 4Institute of Chemistry - Analytical Chemistry, Karl-Franzens University, Graz, Austria, 5Institute of Legal Medicine and Traffic Medicine, University Hospital, Heidelberg, Germany

Diffuse axonal injury can be observed following traumatic brain injury (TBI) and might be associated with diffusivity changes. Therefore, fractional anisotropy and mean diffusivity values were investigated using in situ diffusion tensor imaging in corpses having died of TBI and an uninjured age and temperature matched control group. Additionally, wet-to-dry mass ratios of the same regions were determined to estimate influence of posttraumatic edema. Decreased fractional anisotropy and significantly increased mean diffusivity values were observed in posttraumatic white matter regions. In combination with indifferent wet-to-dry mass ratios these results might suggest a direct influence of traumatic injury on postmortem diffusivity.

3710.   63 Pathophysiological changes in contusions post traumatic brain injury: insights from diffusion tensor imaging
Virginia Newcombe1,2, Guy Williams2, Joanne Outtrim1, Doris Chatfield1, Giulia Abate1, Thomas Geeraerts1, Anne Manktelow1, Hywel Room1, Leela Mariappen1, Peter Hutchinson3, Jonathan Coles1, and David Menon1,2
1Division of Anaesthesia, Cambridge University, Cambridge, Cambridgeshire, United Kingdom, 2Wolfson Brain Imaging Centre, Cambridge University, Cambridge, Cambridgeshire, United Kingdom, 3Academic Department of Neurosurgery, Cambridge University, Cambridge, Cambridgeshire, United Kingdom

Traumatic brain injury (TBI) is often exacerbated by secondary events that lead to secondary brain injury, and represent potentially modifiable cause of mortality and morbidity post TBI. One potential means of improving such translation is to characterise tissue at risk using early imaging studies, and define markers of injury progression in these tissue compartments to use as biomarkers. This study used diffusion tensor imaging to characterise contusions and their growth during the acute phase of injury. Distinct regions were observed including a low diffusivity rim that may represent an area of at risk tissue (a “traumatic penumbra”) following TBI which may be a potential target for therapy.

3711.   64 Detecting Mild Traumatic Brain Injury at the Acute Stage: a Diffusion Tensor Imaging Investigation and Neurocognitive assessment
Zhifeng Kou1, Ramtilak Gattu2, Randall Benson3, Hardik Doshi4, Jie Yang5, Valerie Mika4, Grace Ma6, Robert Welch7, John Woodard8, Scott Millis9, and E Mark Haacke1
1Biomedical Engineering and Radiology, Wayne State University School of Medicine, Detroit, MI, United States, 2Radiology, Wayne State University School of Medicine, Detroit, MI, United States, 3Neurology and Radiology, Wayne State University School of Medicine, Detroit, MI, 4Biomedical Engineering, Wayne State University, Detroit, MI, United States, 5Radiology, Wayne State University, Detroit, MI, United States, 6Wayne State University School of Medicine, Detroit, MI, United States, 7Emergency Medicine, Wayne State University School of Medicine, Detroit, MI, United States, 8Psychology, Wayne State University, Detroit, MI, United States, 9Physical Medicine and Rehabilitation, Wayne State University, Detroit, MI, United States

There is limited data reported the neurocognitive status and their injury pattern of mild traumatic brain injury at the acute stage. Our data demonstrated significant neurocognitive deficits and DTI white matter lesions in mild traumatic brain injury patients at the acute stage.

3712.   65 Microscopic damage to the left hemisphere contributes in determining neglect in patients with a right focal lesion
Chiara Mastropasqua1,2, Marco Bozzali1, Mara Cercignani1,3, Barbara Basile1, Sonia Bonnì4, and Giacomo Koch4,5
1Neuroimaging laboratory, Santa Lucia Foundation IRCCS, Rome, Italy, 2Neuroscience, Trieste University, Trieste, Italy, 3Brighton & Sussex Medical School,Clinical Imaging Sciences Centre, University of Sussex, Brighton, United Kingdom, 4Laboratory of Clinical and Behavioural Neurology, Santa Lucia Foundation IRCCS, Rome, Italy, 5Stroke Unit, Department of Neuroscience, University of Rome Tor Vergata, Rome, Italy

Using tract-based spatial statistics (TBSS), we investigated the contribution of left hemisphere (LH) microstructural white matter (WM) changes in accounting for the presence and severity of hemispatial neglect in patients suffering from right-side stroke. TBSS analysis revealed a diffuse reduction of FA in most WM tracts of the LH, and a an association between neuropsychological measures of neglect severity and FA values in the region of the CC connecting the two parietal cortices. This study supports, on a microstructural basis, the theory that hemispatial neglect originates, by disconnection mechanism, from an unbalance of interhemispheric interaction between the two parietal cortices.

3713.   66 Neurostructural integrity is damaged by HCV mono-infection and HIV/HCV Co-infection: A Diffusion Tensor Imaging Study
Manoj Kumar Sarma1, Rajakumar Nagarajan1, April Thames2, Vanessa Streiff 3, Tim Arentsen3, Stella Panos4, Jason Smith3, Charles H Hinkin2,3, and M. Albert Thomas1
1Radiological Sciences, UCLA School of Medicine, Los Angeles, CA, United States, 2Psychiatry, UCLA School of Medicine, Los Angeles, CA, United States, 3VA Greater Los Angeles Healthcare Service, Los Angeles, CA, United States, 4UCLA School of Medicine, Los Angeles, CA, United States

The synergistic effects of human immunodeficiency virus (HIV) co-infection on Hepatitis C virus (HCV) remains poorly understood with only a few studies on neuropsychological sequelae. Here, using diffusion tensor imaging and employing an automated atlas based analysis, we examined the neurostructural effects of HCV mono-infection and HIV/HCV co-infection through two markers, mean diffusivity (MD) and fractional anisotropy (FA). We investigated sixteen HCV mono-infected, eleven HIV/HCV co-infected, and fifteen healthy controls. We found widespread brain regions with elevation of MD and increase/decrease of FA values in both HCV/HIV co-infected and HCV mono-infected adults relative to healthy controls. The decrease in white matter (WM) integrity is best seen in increases in MD. Indications of WM axonal integrity present a more complicated picture, with both increased and decreased FA.

3714.   67 Fractional Anisotropy Differences in Basal Ganglia in Neurological and Neurodegenerative disorders
Gonzalo Pajares1, Juan Antonio Hernández-Tamames2, Pablo García-Polo3, Norberto Malpica2, Ana Ramos4, and Juan Álvarez-Linera5
1Fundación CIEN - Fundación Reina Sofía, Madrid, Madrid, Spain, 2Universidad Rey Juan Carlos, Spain, 3Centro de Tecnología Biomédica, Spain, 4Hospital Universitario 12 de Octubre, Spain, 5Hospital Ruber Internacional, Spain

The aim of the present work is to study differences in the basal ganglia in several diseases, using Diffusion Tensor Imaging. Although no differences in gray matter are expected when using this technique, an increase in Fractional Anisotropy values has been observed in patients with respect to controls. Depending on the pathology, this increase affecs different structures: substantia nigra in PD; pallidus, putamen and substantia nigra in PSP, or pallidus, putamen and frontal cortex in m-MCI and AD. These results seem to related to the accumulation of iron in the brain.

3715.   68 Diffusion tensor imaging analysis with tract-based spatial statistics of the white matter abnormalities in early-treated phenylketonuria
Huiling Peng1, Amanda J. Moffitt1, Dawn Peck1, Desirée A. White2, and Shawn E. Christ1
1University of Missouri, Columbia, Missouri, United States, 2Washington University, St. Louis, Missouri, United States

Phenylketonuria (PKU) is a genetic condition characterized by an impaired ability to metabolize the amino acid phenylalanine into tyrosine, a precursor of dopamine and other neurotransmitters. The aim of this study was to investigate white matter fiber changes in individuals with early-treated PKU (ETPKU) by means of tract-based spatial statistics (TBSS) approach. Significant reductions of axial, radial, and mean diffusivity were detected in numerous white matter tracts of patients with ETPKU compared to normal controls. A negative correlation between age and mean value of all diffusivity of the whole brain white matter skeleton was also found within the ETPKU group.

3716.   69 Selective white matter connectivity loss (LoCo) identified in the brain-reward system of alcohol dependent individuals
Amy Kuceyeski1, Dieter Meyerhoff2,3, Timothy Durazzo2,3, and Ashish Raj1
1Radiology, Weill Cornell Medical College, New York, NY, United States, 2Radiology and Biomedical Engineering, University of California San Francisco, San Francisco, CA, United States, 3Center for Imaging of Neurodegenerative Diseases, San Francisco Veterans Administration Medical Center, San Francisco, CA, United States

In this study, we implement a recently developed measure called the Comparative Connectivity Loss (CCL) that gives the amount of white matter connectivity disruption for a particular gray matter region, and apply it to a group of alcohol-dependent cohorts. We show that the Brain Reward System is preferentially disrupted, without leading to more widespread and global network changes. We also show that the CCL is a more sensitive and specific metric than gray matter atrophy when differentiating between alcohol dependent individuals and non/light drinking controls.

3717.   70 Abnormal anterior corpus callosum white matter integrity in heavy smokers revealed by tract-based spatial statistics
Fuchun Lin1, Guangyao Wu2, Shiqi Yang2, Haopeng Peng2, Prasanna Ghimire2, Ling Zhu2, Guobing Liu2, and Hao Lei1
1State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China, 2Department of Magnetic Resonance Imaging, Zhongnan Hospital, Wuhan University, Wuhan, China

Tract-based spatial statistics was used to investigate white matter integrity in heavy smokers. Compared to healthy non-smokers, smokers show abnormalities in the left anterior corpus callosum connecting the bilateral orbifrontal and prefrontal cortices. The decreased FA in this region was reflected by decreased axial diffusivity and increased radial diffusivity, which is probably caused by axonal loss and disrupted integrity of myelin. Moreover, in smokers, radial diffusivity in the left anterior corpus callosum was positively correlated with the duration of smoking. Our findings suggested that longer exposure to cigarette smoking is associated with decreased microstructural integrity of the left anterior corpus callosum in smokers.

Yamada Hirofumi1, Yamamoto Akira1, Okada Tomohisa1, Kanagaki Mitsunori1, Kasahara Seiko1, Sawada Takeshi1, Morimoto Emiko1, Sakamoto Ryo1, Okuchi Sachi1, and Togashi Kaori1
1Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University, Kyoto, Kyoto, Japan

We investigated diffusion tensor imaging (DTI) parameters of the optic radiation by region of interest (ROI) analysis of readout segmented DTI (RS-DTI) with healthy volunteers. In ROI analysis we observed significant differences of radial diffusivity (RD), fractional anisotropy (FA) and apparent diffusion coefficient (ADC) between the external sagittal stratum and the internal sagittal stratum. We suppose these differences may reflect the disparities of myelination rather than that of axonal density.

3719.   72 DTI assessment of sensory-motor pathways in children with cerebral palsy
Anastasiya Batrachenko1,2, Arnaud Guidon1,3, Jessica Sun4, Mohamad Mikati5, Joanne Kurtzberg6,7, and Allen W Song1,8
1Brain Imaging and Analysis Center, Duke University, Durham, North Carolina, United States, 2Medical Physics, Duke University, Durham, North Carolina, United States, 3Biomedical Engineering, Duke University, Durham, North Carolina, United States, 4Pediatrics, Pediatric Oncology, Duke University, Durham, NC, United States, 5Pediatric Neurology, Duke University, Durham, North Carolina, United States, 6Pediatrics, Pediatrics Blood & Marrow Transplantation, Duke University, Durham, NC, United States, 7Pathology, Duke University, Durham, NC, United States, 8Radiology, Duke University, Durham, North Carolina, United States

In this study, we correlate diffusion connectivity metrics of the corticospinal tract with clinical behavioral scores in children with cerebral palsy undergoing autologous cord blood stem cell treatment. In diplegic and quadriplegic patients, total tract volumes were shown to have a significant inverse linear correlation with the disease severity scores. In hemiplegic patients, the fraction of the affected tract volume generally tends to decrease with greater disease severity, but also suggests cases of possible functional compensation by the unaffected tract. Standardized quantitative DTI will furthermore help characterize causes and effects of cerebral palsy manifestations and the treatment response mechanisms.
Electronic Poster Session - Neuro B

Clinical Diffusion & Tractography
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  10:00 - 11:00

  Computer #  
Clarisse Longo dos Santos1,2, Oliver Riff1, Claire Ewenczyk3,4, Jerôme Yelnik3,5, Cecile Gaudebout3,4, Eric Bardinet2,6, Linda Marrakchi-Kacem1,3, Sara Fernandez Vidal3,6, Chantal Francois3,5, Marie-Laure Welter3,4, Bertrand Gaymard3,4, Cecile Gallea2,3, Salma Mesmoudi5, Sophie Lecomte1, Habib Benali5, Stephane Lehericy2,3, Marie Vidailhet3,4, and Cyril Poupon1
1Neurospin, CEA/I2BM, Gif-sur-Yvette, France, 2CR-ICM / CENIR, Paris, France, 3CR-ICM / AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Faculté de Médecine, Paris, 4Centre d’Investigation Clinique, Fédération des Maladies du Système Nerveux, France, 5INSERM, 6CNRS-UMR7225, France

We have combined structural and diffusion magnetic resonance imaging to investigate the connectivity of the pedunculopontine nucleus (PPN) region in Parkinson's disease and Progressive supranuclear palsy patients. A total of 87 participants were recruited, including 45 patients PD, 12 patients PSP and 30 age-matched controls. Images were acquired using a 3T (Trio Siemens; T1; T2; diffusion 60 directions b-value 1500s/mm²) and a 7T (Trio Siemens; T2* 0.6x0.6x0.6mm3). Data analysis was performed using BrainVISA/Connectomist-2.0 and FreeSurfer tools. Preliminary results suggest that the method used here can effectively show the topographical representation of the connections between PPN and the motor cortex.

3721.   74 Can structural connectivity studies be performed in children with servere ataxias?
Stephen Rose1, Kerstin Pannek2, Kate Sinclair3, and Martin Lavin4
1University of Queensland, Brisbane, Queensland, Australia, 2University of Queensland, 3Royal Childrens Hospital, 4Queensland Institue for Medical Research

Structural connectivity studies employing diffusion-weighted MRI (dMRI) and probabilistic tractography can provide new insight into the loss in integrity of important white matter (WM) motor pathways. However, such imaging studies in children with severe ataxias present a significant challenge, due to the likelihood of artifacts induced by involuntary head movement. To overcome this constraint, we have developed an image processing strategy to reduce such effects and present novel information about the degeneration of specific cerebellar-corticomotor pathways in children with ataxia-telangiectasia (A-T). Such information improves our understanding of the clinical phenotype in A-T.

3722.   75 Impact of Fiber Tracking on Neurosurgery Using an Intra-operative 3.0T MR System
Sanju Lama1, Boguslaw Tomanek2, and Garnette R Sutherland1
1Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada, 2Clinical Neurosciences, Experimental Imaging Center, University of Calgary, Calgary, Alberta, Canada

Intra-operative MR imaging (iMRI) and fiber tracking using Diffusion Tensor Imaging (DTI) provides 3D knowledge of white matter tracts anatomy and their relationship to neurosurgical pathology intra-operatively. Image quality and definition is dependent on magnetic and gradient field strengths. A single center prospective study including 177 patients using 3.0T iMRI system, showed that intra-operative DTI tractography can be a valuable adjunct to neurosurgery affecting neurosurgical planning in up to 16% of cases. Furthermore such a discipline provided an excellent educational forum for the discussion of white matter anatomy in relation to the target lesion amongst residents and staff neurosurgeons.

3723.   76 The impact of extreme prematurity on motor tract development in adolescence
Linda Chan1, Deanne K Thompson1, Peter J Anderson1, Alan Connelly2, Jeanie Cheong1, and Lex W Doyle1
1Murdoch Childrens Research Institute, Royal Children's Hospital, University of Melbourne, Melbourne, Victoria, Australia, 23Brain Research Institute, Florey Neuroscience Institutes, Melbourne, Victoria, Australia

Extremely preterm birth or extremely low birth weight are associated with brain white matter abnormalities and motor impairments. Structural and diffusion MRIs were obtained in 186 extremely preterm and 136 full-term adolescents at 18 years of age. Constrained spherical deconvolution tractography was performed. Extremely preterm infants had altered microstructural organization in the superior corticospinal tract regions, which related to neonatal brain injury. Motor impairment was related to reduced tract volume. Thus, preterm adolescents may have delayed corticospinal tract development. This may be a consequence of neonatal brain injury, and may relate to impaired motor outcomes in extreme prematurity.

3724.   77 Delayed, progressive white matter loss following traumatic brain injury, demonstrated using probabilistic tractography
Virginia Newcombe1, Linus Schumacher2, Guy Williams3, Jo Outtrim1, Anne Manktelow1, Jonathan Coles1, Peter Hutchinson4, Marta Correia2, and David Menon1
1Division of Anaesthesia, Cambridge University, Cambridge, Cambridgeshire, United Kingdom, 2MRC Cognition and Brain Sciences Unit, Cambridge University, 3Wolfson Brain Imaging Centre, Cambridge University, 4Academic Department of Neurosurgery, Cambridge University

Traumatic brain injury (TBI) is a major cause of morbidity and mortality worldwide. It is clear that many of the sequelae are not just direct consequences of the acute but event represent dynamic processes with changes occurring many years after the precipitating injury. In this study, the temporal course of white matter injury from acute to chronic phases after injury was quantified using probabilistic tractography. Such knowledge of longitudinal change is important to aid interpretation of imaging findings, to provide further insight into pathophysiology, and help to provide a framework that allows DTI to be used as an imaging biomarker of therapy response.

3725.   78 DTI tractography reveals changes in the optic radiation of patients with persistent visual failure following surgery for tumours causing optic chiasm compression
Andrew D Nichols1,2, Bradford A Moffat3,4, Helen V Danesh-Meyer5, and Andrew H Kaye1,2
1Department of Surgery (RMH/WH), University of Melbourne, Melbourne, Victoria, Australia, 2Department of Neurosurgery, Royal Melbourne Hospital, Melbourne, Victoria, Australia, 3Department of Radiology, University of Melbourne, Melbourne, Victoria, Australia, 4Department of Radiology, Royal Melbourne Hospital, Melbourne, Victoria, Australia, 5Department of Ophthalmology, University of Auckland, Auckland, New Zealand

Brain tumours can cause optic chiasm compression and lead to visual deficits. This is the first study to use diffusion tensor imaging tractography of the optic radiation to investigate the downstream effects of brain tumours in these patients. In this study, patients with persistent visual deficits lasting over one year post surgery show decreased fractional anisotropy, increased radial diffusivity and decreased optic radiation size compared to patients with normal vision. Additional diffusion tensor imaging tractography studies of the visual pathway in these patients will continue to investigate the relationship between tumours causing optic chiasm compression and visual deficits.

3726.   79 Altered functional significance of structural connectivity for language processing in autism spectrum disorders
Yu-Chun Lo1, Susan Shur-Fen Gau2, and Wen-Yih Isaac Tseng1,3
1Center for Optoelectronic Biomedicine, National Taiwan University College of Medicine, Taipei, Taiwan, 2Department of Psychiatry, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan, 3Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan

This study investigated structural connectivity of the dorsal and ventral pathways of the language network using diffusion spectrum imaging tractogrpahy, and its functional significance corresponding to verbal IQ (VIQ) and verbal comprehension index (VCI). The results showed that structural connectivity of the left dorsal pathway in neurotypicals was associated with VIQ (r = 0.493, p=.0027), whereas structural connectivity of the left ventral pathway was associated with VCI (r = 0.447, p=.0048). These findings suggest that the functional significance of structural connectivity for language processing is altered in ASD.

3727.   80 Diffusion Spectrum Imaging Tractography Study of Ventral and Dorsal Pathways for Language in Schizophrenia
Chen-Hao Wu1, Hai-Go Hwu2, Chih-Ming Liu2, Chen-Chung Liu2, Chung-Ming Chen1, and Wen-Yih Isaac Tseng3,4
1Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan, 2Department of Psychiatry, National Taiwan University Hospital, Taipei, Taiwan, 3Center for Optoelectronic Biomedicine, National Taiwan University College of Medicine, Taipei, Taiwan, 4Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan

Diffusion Spectrum Imaging Tractography Study of Ventral and Dorsal Pathways for Language in Schizophrenia Schizophrenia is a mental disorder that goes along with progressively feeble symptoms. The clinical manifestations include auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking with significant social or occupational dysfunction. Abnormalities within language-related brain structures have been associated with clinical symptoms in schizophrenia. Recent functional and anatomical studies suggest that two distinct white matter tracts, called ventral and dorsal pathways provide communication between the two regions that are crucial to language processing. In this study, we used diffusion spectrum imaging tractography to reconstruct the connections involved in the ventral and dorsal pathways for language and to study the alteration of its structural connectivity in schizophrenia.

3728.   81 An objective tractography method using a diffusion spectrum imaging (DSI) template
Yu-Chun Lo1, Yung-Chin Hsu2, Hsiao-Lan Sharon Wang1, and Wen-Yih Isaac Tseng1,3
1Center for Optoelectronic Biomedicine, National Taiwan University College of Medicine, Taipei, Taiwan, 2Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Taiwan, 3Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan

Diffusion tractography has raised interests in the neuroscience community for in vivo tracking of white matter fiber pathways. This technique, however, requires substantial maneuver and thus very subjective and less reproducible. In this study we proposed a standard procedure of tractography that could minimize the human intervention. This procedure entailed a diffusion spectrum imaging (DSI) template on which interested fiber pathways and their ROIs were determined once for all. The proposed method may improve the reproducibility and efficiency of tractography-based analysis that involves multiple pathways in a large number of subjects.

3729.   82 The LoCo (Loss in Connectivity) tool: a new way to investigate changes to the structural brain network in various types of disease or injury
Amy Kuceyeski1, Norman Relkin2,3, and Ashish Raj1
1Radiology, Weill Cornell Medical College, New York, New York, United States, 2Neurology and Neuroscience, Weill Cornell Medical College, New York, New York, United States, 3NewYork-Presbyterian Hospital, New York, NY, United States

There are many tools to assess pathologic brain changes with MRI, but, to our knowledge, the LoCo (Loss in Connection) Tool presented here is the first that associates localized white matter (WM) lesions with disruptions in gray matter connectivity as a step toward understanding the lesions’ functional implications. This tool uses tractograms (set of WM fibers) from a large set of normal healthy individuals in a common space (MNI) to assess structural local and global network disruption related to a WM lesion mask. We apply this methodology to patients with Normal Pressure Hydrocephalus, and show large amounts of orbital-frontal disruption.

3730.   83 Integration of Tractography with Deep Brain Stimulation Modeling
Kyle Taljan1,2, Angela Noecker2, Ken Sakaie3, Mark Lowe3, and Cameron McIntyre2
1Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States, 2Biomedical Engineering, Cleveland Clinic Lerner Research Institute, Cleveland, OH, United States, 3Cleveland Clinic Imaging Institute, Cleveland, OH, United States

Deep brain stimulation, an effective treatment of movement disorders such as Parkinson's disease, can cause cognitive side effects. It is hypothesized that stimulation of tissue connected to motor cortex is beneficial whereas stimulation of tissue connected to nonmotor regions leads to side effects. Previous work showed a reduction in side effects by optimizing stimulation so that the volume of tissue activated was limited to motor regions of the subthalamic nucleus. We use tractography to compare anatomical connectivity of a VTA associated with side effects and one that limited side effects. The VTA associated with side effects showed greater anatomical connectivity to non-motor cortical regions than the model based VTA. This preliminary result points to the potential of integrating diffusion MR-based tractography with stimulation modeling in deep brain stimulation to improve patient outcomes.

3731.   84 Characterization of Pediatric Bipolar Disorder with Quantitative HARDI Tractography Metrics
Ryan Payne Cabeen1, Daniel Dickstein2, and David H Laidlaw1
1Computer Science, Brown University, Providence, RI, United States, 2Psychiatry & Human Behavior, Brown University, Providence, RI, United States

We computed and compared quantitative diffusion tractography metrics in three children with bipolar disorder (BD) and three typically-developing controls (TDC) without psychiatric illness. An automated process was used to choose tracks connecting the amygdala and accumbens, a track of interest (TOI) chosen a priori from previous findings in voxel-based morphometry (VBM) and resting state functional connectivity (RSFC) analysis. We found decreases in mean FA and sum length-weighted FA in left hemisphere tracks of the BD group. No differences were found in right hemisphere metrics or subcortical volumes.

3732.   85 Understanding the Effects of Prematurity on the Visual System using Diffusion MRI
Dolly Thai1, Deanne K Thompson1,2, Lex W Doyle1,3, Jeanie Cheong1,3, Michael J Kean1, Jeff Neil4, Terrie E Inder1,4, Peter J Anderson1, and Rod W Hunt1
1Murdoch Childrens Research Institute, Royal Children's Hospital, University of Melbourne, Melbourne, Victoria, Australia, 2Centre for Neuroscience, Florey Neuroscience Institutes,University of Melbourne, Melbourne, Victoria, Australia, 3Royal Women's Hospital, Melbourne, Victoria, Australia, 4St Louis Children’s Hospital, Washington University in St Louis, St Louis, Missouri, United States

Children born very preterm are at risk of developing visual impairments. This study examines 142 very preterm and 32 full-term 7 year old children scanned with a 3T MRI scanner. Optic radiations were reconstructed using constrained spherical deconvolution. Radial diffusivity was significantly higher in preterm children, thus myelination appears to be particularly disrupted, especially in the more anterior segments of the optic radiation. These changes were associated with visual field defects and poorer visual acuity. In conclusion, the microstructural organisation of the optic radiation is less developed in preterm children, which negatively impacts visual function at seven years.

3733.   86 Quantitative Evaluation of Cortico-callosal Wallerian Degeneration with Diffusion Tensor Imaging in Moderate Traumatic Brain Injury
Richa Trivedi1, Maria M D'souza1, Hemal Grover1, Ajay Chaudhary2, Pawan Kumar1, Prabhjot Kaur1, Rajendra P Tripathi1, and Subash Khushu1
1Institute of Nuclear Medicine and Allied Sciences, Delhi, Delhi, India, 2Neurosurgery, Dr. Ram Manohar Lohia Hospital, Delhi, Delhi, India

Given the widespread interhemispheric connections that course through the corpus callosum (CC), callosal pathway disruptions can have a profound impact on cognitive functioning. Serial quantitative diffusion tensor tractography was performed in five patients with moderate unifrontal lobe TBI. On follow-up study, significantly reduced callosal FA values were observed on moving from controls to injured hemisphere through contra-lateral normal appearing hemisphere in the subregions of anterior CC. We conclude that DTT based quantification in frontal lobe injury may be useful for wide spread assessment of DAI in callosal fibers and help in prognosticating disease outcome.

3734.   87 Spread of discharges through tracks identified with diffusion tractography may explain transient splenial "lesions" in epilepsy
David Vaughan1, Jacques-Donald Tournier1,2, Alan Connelly1,2, and Graeme Jackson1,2
1Brain Research Institute, Florey Neuroscience Institutes, Melbourne, Victoria, Australia, 2Department of Medicine, University of Melbourne, Victoria, Australia

A transient "lesion" of the splenium of the corpus callosum occasionally occurs in patients with epilepsy. The cause remains unknown. We present probabilistic fibre tracking in such a patient, from the ictal onset zone to the contralateral region of seizure spread. Tracks that traversed the corpus callosum all passed through the splenium at the site of the lesion, and similar tracks were identified in non-epileptic controls. We suggest the lesion is related to excess epileptic activity in this pathway.

3735.   88 A Parametric Approach to Evaluating the Statistical Significance of Pathway Dependent Diffusion Measures
Mark J Lowe1, Ken E Sakaie1, Jian Lin1, Lael Stone2, and Micheal D Phillips1
1Imaging Institute, Cleveland Clinic, Cleveland, OH, United States, 2Neurologic Institute, Cleveland Clinic, Cleveland, OH, United States

We have previously introduced pathway dependent diffusion measures as a way of determining functionally relevant disease burden in multiple sclerosis. This method determines the mean diffusion properties (i.e. FA, radial diffusivity, longitudinal diffusivity) along a pathway determined with probabilistic tractography. There is a significant drawback to the method in that the sensitivity can be quite low due to the fact that tissue diffusion parameters will vary substantially along some pathways. In this study, we utilize a parametric approach to determining local pathway diffusion properties and derive a statistical approach to determine if a given fiber path contains significant disease burden.

3736.   89 Skeletonized white matter atlas and atlas-based segmentation
Shengwei Zhang1, and Konstantinos Arfanakis1
1Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, United States

This work demonstrated that diffusion imaging studies employing automated ROI selection by means of conventional atlas-based segmentation suffer from misregistration. We adopted the main principles of TBSS and proposed an alternative automated approach, termed here “skeletonized atlas-based segmentation”, which is relatively immune to misregistration. Furthermore, a new skeletonized atlas was developed in ICBM152 space based on the IIT2 DTI template. The combination of the whole brain DTI template and skeletonized WM atlas has the potential to increase the accuracy and sensitivity of both voxel-wise and ROI analyses in DTI as well as high-angular resolution diffusion imaging studies.

3737.   90 Information Theory Based Quantification Of DTI Alterations In Cognitive Impairment
Norbert W. Schuff1,2, Yu Zhang3, Karl Young4, Howard Rosen4, and Michael W. Weiner1,5
1UCSF, San Francisco, CA, United States, 2VAMC, San Francisco, California, United States, 3UCSF, San Francisco, California, United States, 4UCSF, 5VAMC

The best approach for maximizing information from diffusion tensor imaging (DTI) is a matter of intense debate, especially when it comes to quantifying the integrity of nerve fiber bundles. We explored the value of information theoretic measures, such as Kullback-Leibler divergence, for quantifying DTI variations along fibers as indeces of fiber uniformity. Simulations suggest that the approach is useful for capturing global and local features. We also applied the approach to experimental DTI data from patients with cognitive impairments, including Alzheimer’s disease (AD). The results are consistent with the idea that AD is associated with diminishing structures within fiber bundles.

3738.   91 Respiratory Triggered Diffusion Tensor Imaging MR of the kidney at 3T
Lorenzo Mannelli1, Theodore J Dubinsky1, Mariam Moshiri1, Manjiri K Dighe1, and Jeffrey H Maki1
1University of Washington, Seattle, WA, United States

The kidney is very appealing to be studied with DTI because of the renal medulla radially oriented architecture. The main challanges are differentiating the vascular flow from the tubular flow, and an acquisition tecnique easy to apply in clinical practice

3739.   92 High-field brain structural connectivity at 7T compared to 3T using HARDI
Liang Zhan1, Neda Jahanshad1, Christophe Lenglet2, Bryon A. Mueller3, Guillermo Sapiro4, Noam Harel2, Kelvin O. Lim3, and Paul M. Thompson1
1Department of Neurology, University of California, Los Angeles, Los Angeles, CA, United States, 2Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States, 3Dept. of Psychiatry, Univ. of Minnesota, Minneapolis, MN, United States, 4Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, United States

High-field diffusion imaging can be used to map anatomical connectivity in the living brain, but little is known about how the resulting connectivity maps compare to those obtained at lower fields. Five young healthy subjects (two male, age: 32.4±14.6 years) were scanned at 3T and with a 7T protocol with 1.5mm isotropic voxels (called “7T-1.5mm” below). To assess field strength effects while keeping voxel size constant, we also scanned 2 of the 5 subjects using a protocol called “7T-2mm” for comparison purposes. Connections between rostral anterior cingulate and the lateral orbitofrontal, caudal middle frontal and rostral middle frontal cortex in the left hemisphere were more prominent at 7T-1.5mm, and showed the most significant differences by protocol. Smaller voxels allowed more connections to be recovered, particularly shorter ones, and this affected the relative prominence of different connections in the matrices.

3740.   93 Investigation of vibration induced artifacts in clinical diffusion weighted imaging of the brain
Madison Berl1, Lindsay Walker2, Joelle Sarlls3, and Carlo Pierpaoli4
1Children's Research Institute, Children's National Medical Center, Washington, DC, United States, 2Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, United States, 3STBB, National Institutes of Health, Bethesda, MD, United States,4NICHD, National Institutes of Health, Bethesda, MD, United States

We expand on a systematic vibration artifact in three important ways: 1) the artifact is more widespread than first described, 2) we offer another potential solution to reduce the artifact and 3) identify that the artifact may be the basis of a clinical misinterpretation that has been cited as evidence to change policy and practice.
Electronic Poster Session - Neuro B

Aging & Dementia
Click on to view the abstract pdf and click on to view the video presentation. (Not all presentations are available.)
Wednesday 9 May 2012
Exhibition Hall  11:00 - 12:00

  Computer #  
73 Brain Iron Levels Across the Japanese Macaque Lifespan
Yosef A. Berlow1,2, Steve Kohama3, James Pollaro1, Manoj Sammi1, and William Rooney1,2
1Advanced Imaging Research Center, Oregon Health & Science University, Portland, OR, United States, 2Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States, 3Oregon National Primate Research Center, Oregon Health & Science University, Portland, OR, United States

This study measured age associated brain iron accumulation in Japanese macaques (JM) and humans. Eighty-eight JM and 43 healthy human control subject were included. Proton density and T2-weighted TSE images were used to calculate R2 maps. The effects of age on R2 were modeled in caudate, putamen and pallidum. JM R2 values increase rapidly during the first two decades of life and then begin to plateau at levels that are much greater than those seen in humans. These findings suggest that JM accumulate brain iron throughout their adulthood and attain brain iron concentrations that are much greater than humans.

3742.   74 Arterial spin labeling reproducibility and potential for predicting hemodynamic alterations in older adults at risk for Alzheimer’s disease
Tracy L. Wilson1, Brandon A. Ally2,3, Erin P. Hussey3, Swati D. Rane1, Tricia A. Thornton-Wells4,5, Shashwath A. Meda4,5, John C. Gore1, and Manus J. Donahue1,2
1Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States, 2Psychiatry, Vanderbilt University, Nashville, TN, 3Neurology, Vanderbilt University, Nashville, TN, 4Center for Human Genetics Research, Vanderbilt University, Nashville, TN, 5Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN

Noninvasive MRI approaches capable of assessing tissue-level modulations in cerebral hemodynamics hold significant potential for gauging disease severity and progression in patients with, and at-risk for, Alzheimer's disease (AD). We implemented a customized arterial spin labeling (ASL) sequence specifically capable of assessing cerebral blood flow (CBF), simultaneously in cortical and subcortical structures. The ASL technique implemented showed high reproducibility in young and older adults. In patients, we observed positive relationships between cortical CBF and cognitive performance in all volunteers, but an inverse trend between hippocampus CBF and cognitive performance in at-risk and control participants.

3743.   75 Aging Effects on Cerebrovascular Response to Breath Holdings as Measured by Blood Oxygenation-Level Dependent MRI
Yuan-Yu Hsu1,2, Ho-Ling Liu3, Ling-Yi Huang1,3, and Kun-Eng Lim1,2
1Radiology, Buddhist Tzu Chi General Hospital-Taipei Branch, Xindien, Taipei, Taiwan, 2School of Medicine, Tzu Chi University, Hualien, Hualien, Taiwan,3Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan

This study aimed to evaluate the regional differences in cerebrovascular response to hypercapnia challenges between young and elderly adults. Twenty young (F/M = 10/10, mean age = 28.2 y/o) and twenty elderly (F/M = 12/8, mean age = 64.4 y/o) adults were studied by 3-T BOLD MRI during repeated 15-second breath-holdings. Significant breath-hold regulated BOLD signal increases were identified in gray matters. Compared to the young group, the elderly had a 50% decrease in the activation volume. There were significantly less BOLD signal increase in amygdala and dentate nucleus in elderly than in young adults (P < 0.001).

3744.   76 Multi-modal MRI analysis for assessing memory impairment in the early stages of AD
Swati Rane1, Tracy Porchak1, Brandon Ally2, Erin Hussey2, Tricia Thornton-Wells3,4, Shashwath Meda3, John C Gore1,5, and Manus Donahue1,6
1Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States,2Neurology, Psychiatry, Vanderbilt University, Nashville, TN, United States, 3Center for Human Genetics Research, Vanderbilt University, Nashville, TN, United States, 4Molecular Physics and Biophysics, Vanderbilt University, Nashville, TN, United States, 5Biomedical Engineering, Vanderbilt University, Nashville, TN, United States, 6Psychiatry, Vanderbilt University, Nashville, TN, United States

A multi-modal comparison comprising of baseline BOLD and ASL was employed to compare mechanisms of verbal memory deficits in healthy older adults, adults at risk of Alzheimer’s disease and adults with MCI. Alterations in the default mode network and their correlation with baseline blood flow were studied. Further, synchrony of BOLD fluctuations between the hippocampus and the precuneus/posterior cingulate regions of the brain was evaluated and correlated with verbal memory (CERAD) scores.

3745.   77 Early alterations in cerebral oxygen extraction in autosomal-dominant Alzheimer's Disease
Dustin Kenneth Ragan1,2, Randall Bateman3,4, Virginia D Buckles3,4, Jose A Pineda1,3, John C Morris3,4, and Tammie LS Benzinger2,4
1Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, United States, 2Department of Radiology, Washington University School of Medicine, St. Louis, MO, United States, 3Department of Neurology, Washington University School of Medicine, St. Louis, MO, United States,4Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO, United States

We investigated early changes to cerebral oxygen extraction in patients who had a familiar history of autosomal-dominant Alzheimer’s Disease by measuring magnetic susceptibility in cerebral veins. Oxygen extraction was showed a decrease around the age of onset, with a return to normal values 5 years after onset. This may indicate an important early marker of the disease process.

3746.   78 A comparative study of rCBF maps with Arterial Spin Labeling and FDG-PET in Dementia and Alzheimer's Disease
Pablo Garcia-Polo Garcia1, Juan Antonio Hernández-Tamames2, Roberto García-Álvarez3, Eva Alfayate4, and Juan Álvarez-Linera5
1Neuroimaging Lab., Centre for Biomedical Imaging, Pozuelo de Alarcón, Madrid, Spain, 2Universidad Rey Juan Carlos, Móstoles, Madrid, Spain,3Research and Collaborations Department, GE Healthcare, Buc, France, 4Cien Foundation - Centre for Alzheimer's Disease Queen Sofia Foundation, Madrid, Spain, 5Hospital Ruber Internacional, Madrid, Spain

Alzheimer's disease (AD) is a type of dementia that exhibits decreased perfusion-metabolism and GM loss in the brain. This work examines the correlation between both rCBF-ASL and FDG-PET in a group of 24 subjects. In addition, ASL was utilized in a second group of 99 subjects (Control, MCI and AD) to assess hypoperfusion in AD. Significant correlation between rCBF and FDG-PET was found. Hypoperfusion patterns were seen in posterior cingulate and posterior lobes in AD. This work demonstrates both: a high correlation between ASL and FDG-PET, and the capability of ASL to become a promising technique to monitor the AD.

3747.   79 Atlas-based quantification with machine-learning based characterization of DTI from patients with mild cognitive impairment and Alzheimer’s disease
Kenichi Oishi1, Michelle M Mielke2,3, Michael I Miller4, Marilyn S Albert5, Constantine G Lyketsos2, and Susumu Mori6,7
1Radiology, Johns Hopkins University, Baltimore, MD, United States, 2Psychiatry and Behavioral Sciences, Johns Hopkins University, 32Division of Epidemiology, College of Medicine, Mayo Clinic, 4Center for Imaging Science, Johns Hopkins University, 5Neurology, Johns Hopkins University,6Radiology, Johns Hopkins University, 7F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute

We applied a machine-learning framework to characterize anatomical alterations of early-stage Alzheimer’s disease (AD), and to investigate a classifier that can predict conversion from mild cognitive impairment (MCI) to AD within 36 months. The Eve atlas was used to measure the fractional anisotropy (FA) and mean diffusivity (MD) of 148 brain structures, followed by principal component analysis (PCA) and support vector machine-based classification. PCA detected subtle but widespread FA&MD alterations related to AD. The trained classifier could differentiate MCI-converters from non-converters with sensitivity of 0.67 and specificity of 1, supporting the potential of DTI in identifying early-stage AD patients.

80 The LoCo: a measure of gray matter structural connectivity loss and its application to neurodegenerative disorders
Amy Kuceyeski1, Yu Zhang2,3, and Ashish Raj1
1Radiology, Weill Cornell Medical College, New York, New York, United States, 2Center for Imaging of Neurodegenerative Diseases, Department of Veteran's Affairs Medical Center, San Francisco, CA, United States, 3Radiology, University of California San Francisco, San Francisco, CA, United States

We implement a metric called Comparative Connectivity Loss (CCL) that gives the amount of structural white matter connectivity disruption incurred by a gray matter region for a particular pattern of white matter integrity loss. This metric is calculated on a standard atlas for three groups, Alzheimer's disease, fronto-temporal dementia, and age-matched normal controls. We show significant correlations of CCL with atrophy patterns in the two diseases. In addition, we show that the CCL outperforms gray matter atrophy when classifying individuals into the three groups, while having similar levels of accuracy with white matter integrity measures of radial and longitudinal diffusivity.

Nico D. Papinutto1,2, Sebastiano Galantucci2,3, Jorge Jovicich1, and Maria Luisa Gorno-Tempini2
1CIMeC, University of Trento, Mattarello, TN, Italy, 2University of California San Francisco, San Francisco, CA, United States, 3Scientific Institute and University Hospital San Raffaele, Milano, MI, Italy

The purpose of this study was to evaluate the extent and localization of white matter (WM) damages in individuals with primary progressive aphasia (PPA) by using Tract-Based Spatial Statistics (TBSS), extending the findings of previous voxel and tract-based analyses of multi-subject Diffusion Tensor Imaging (DTI) data. WM integrity was studied by comparing three groups of patients (three major subtypes of PPA: non-fluent/agrammatic (PNFA), semantic variant (SD) and logopenic variant (LPA)) with a group of age-matched healthy controls. Characteristic patterns of WM damage in the three major variants of primary progressive aphasia were evidenced and characterized by means of TBSS.

3750.   82 Multivariate analysis on hemispheric asymmetry alterations in differentiating mild cognitive impairment and Alzheimer's disease from healthy aging
Xiaojing Long1, Weiqi Liao1, Chunxiang Jiang1, Bensheng Qiu1, Yang Liu1, and Lijuan Zhang*1
1Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China

Relevant structural variates were collectively explored for a comprehensive morphological assessment on brain hemispheric asymmetry alterations among groups of healthy aging, mild cognitive impairment (MCI) converters, and Alzheimer’s disease (AD). Region specific preservation, reduction or reverse of hemispheric asymmetries were found to differ among groups of MCI and AD as compared with healthy aging, which may reflect the underlying mechanisms useful for disease diagnosis, differentiation and monitoring of MCI and AD.

83 Longitudinal Effects of Irradiation and Voluntary Exercise on Hippocampal Gray Matter Loss
Sarah Biedermann1, Johannes Fuss2, Claudia Falfán-Melgoza3, Lei Zheng3, Alexander Sartorius3, Gabi Ende1, Peter Gass2, and Wolfgang Weber-Fahr3
1Neuroimaging, Central Institute of Mental Health, Mannheim, Germany, 2Animal Models in Psychiatry, Central Institute of Mental Health, Mannheim, Germany, 3Translational Imaging, Central Institute of Mental Health, Mannheim, Germany

To reveal underlying mechanisms of exercise-induced gray matter increase, mice underwent hippocampal irradiation, blocking hippocampal neurogenesis, followed by voluntary wheel-running. Voxel based morphometry was performed before and after the exercise period. Age related decreased hippocampal gray matter was seen in all mice after the treatment period. Sham irradiated running mice had higher hippocampal gray matter compared to sedentary mice and a decreased loss of hippocampal gray matter over time, whereas irradiated mice did not have higher hippocampal gray matter after exercise. These findings indicate mechanisms of neuroplasticity in exercise induced hippocampal alterations.

84 Automated multi-atlas segmentation of anatomical brain MR images from elderly subjects.
Aikaterini Kotrotsou1, Niranjini Rajendran2, David A. Bennett2, and Konstantinos Arfanakis1,2
1Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, United States, 2Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, United States

An increasing number of studies use brain MRI to assess volumetric changes due to neurodegenerative diseases in the elderly. Crucial to these studies is segmentation of anatomical brain MRI data. Multi-atlas segmentation is one of the approaches used for automated labeling; however the performance of this method in subjects with age-related atrophy has not been thoroughly investigated. In this work, the performance of multi-atlas segmentation in data from elderly subjects (>80 years of age) was compared to that of FreeSurfer. It was demonstrated that multi-atlas segmentation provides results that are similar to those of FreeSurfer, in a fully automated manner.

85 Compositive morphological alterations in healthy ageing, mild cognitive impairment and Alzheimer's disease: An MANCOVA study
Weiqi LIAO1,2, Xiaojing LONG1,2, Lijuan ZHANG*1,2, Chunxiang JIANG1,2, and Wenhui HUANG1,2
1Paul C Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong Province, China, 2Key Lab of Health Informatics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong Province, China

Multivariate analysis of covariance was performed in addition to ANOVA to compositively evaluate brain morphological alteration indexed by surface area, curvature, cortical thickness, and subjacent white matter volume in groups of healthy ageing, mild cognitive impairment (MCI) converter and Alzheimer¡¯s disease (AD). Age independent global rather than regional specific alterations were revealed to differ significantly among the aforementioned groups. MANCOVA may possess the potential powerfulness of differentiating MCI and AD from healthy ageing where single structural index was not adequate to do so.

3754.   86 High resolution MRI at 21.1 T of the hippocampus and temporal lobe white matter in the differential classification of Alzheimer’s Disease and Diffuse Lewy Body Disorder
Parastou Foroutan1,2, Melissa M Murray3, Shinsuke Fujioka4, Katherine J Schweitzer4, Dennis W Dickson3, Zbigniew K Wszolek4, and Samuel Colles Grant1,5
1Center for Interdisciplinary Magnetic Resonance, The National High Magnetic Field Laboratory, Tallahassee, Florida, United States, 2Imaging, The H. Lee Moffitt Cancer Center, Tampa, Florida, United States, 3Pathology and Neuroscience, The Mayo Clinic, Jacksonville, Florida, United States,4Neurology, The Mayo Clinic, Jacksonville, Florida, United States, 5Chemical & Biomedical Engineering, The Florida State University, Tallahassee, Florida, United States

The two most common forms of dementia are Alzheimer’s disease (AD) and diffuse Lewy Body disorder (DLBD), but clinical similarities make it difficult to distinguish between them. In this study, fixed postmortem sections of human hippocampi diagnosed with AD and DLBD were evaluated using MRI at 21.1 T. The samples were analyzed using high resolution 3D datasets, diffusion-weighted imaging and relaxation maps of T2 and T2* compared to histology to identify MR biomarkers specific to the different pathologies. Data suggests that lower T2 and T2* times are correlated with chronic DLBD while increased relaxation and ADC coincide with chronic AD.

3755.   87 Distinct longitudinal cortical change in frontotemporal lobar degeneration and Alzheimer's disease
Brian B Avants1, Corey McMillan2, Philip A Cook1, James C. Gee3, and Murray Grossman2
1University of Pennsylvania, Philadelphia, PA, United States, 2Neurology, University of Pennsylvania, Philadelphia, PA, United States, 3Radiology, University of Pennsylvania, Philadelphia, PA, United States

We employ quantitative longitudinal neuroimaging to contrast cortical atrophy rates between controls and patients with Alzheimer's disease (AD) or frontotemporal degeneration (FTD) defined on the basis of autopsy-confirmed cerebrospinal fluid (CSF) values of tau:Abeta1-42 ratio. We demonstrate that unbiased quantification of specific cortical regions improves detection power over whole brain analysis in both AD and FTD.

3756.   88 Does Fluid Intake Before Scanning Affect Water Content Measured in Brain?
Sandra M. Meyers1, Irene M. Vavasour2, Cornelia Laule2,3, Shannon H. Kolind4,5, Roger Tam2,6, Burkhard Maedler7, David K. Li2,6, Alex L. MacKay1,2, and Anthony L. Traboulsee8
1Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada, 2Radiology, University of British Columbia, Vancouver, BC, Canada,3Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada, 4FMRIB Centre, University of Oxford, Oxford, United Kingdom, 5Neuroimaging, University College London, London, United Kingdom, 6MS/MRI Research Group, University of British Columbia, Vancouver, BC, Canada, 7University of Bonn, Bonn, Germany, 8Medicine, University of British Columbia, Vancouver, BC, Canada

Accurate water content (WC) measurement is valuable for assessing edema and monitoring effects of therapy. While hydration has been shown to significantly affect brain volume, the effect of fluid intake on MR brain WC is currently unknown. To investigate this question, 20 healthy volunteers were scanned at 3T with 3DT2 and IR sequences four times: (1) baseline, (2) after consuming 3L of water, and (3/4) twice after overnight dehydration. WC was calculated as the integral under the T2 distribution, relative to that of a water standard, with additional corrections. Hydration did not have a significant, measurable effect on brain WC.

3757.   89 3T Automated High Resolution MTR in Alzheimer's Disease and Healthy Elderly Subjects
Ying Wu1,2, Ryan Hutten1, Ana Barion3,4, Michael Mercury3,4, Zoran Grujic5, Victoria Braund3,4, Christopher Glielmi6, Nadia Abbasi1, Ann Ragin7, and Robert R. Edelman1
1Radiology, NorthShore University Health System, Evanston, IL, United States, 2Radiology, University of Chicago, Chicago, IL, United States,3Neurology, NorthShore University Health System, Glenview, IL, United States, 4Neurology, University of Chicago, Chicago, IL, United States,5Neurology, Central DuPage Hospital Neuroscience Institute, Winfield, IL, United States, 6Siemens Healthcare, Chicago, IL, United States, 7Radiology, Northwestern University, Chicago, IL, United States

We demonstrate the findings of a comprehensive automated high resolution magnetization transfer imaging at 3T. The method detected subtle brain changes in the hippocampus, caudate, putamen, cerebral cortex and white matter and differentiated mild Alzheimer’s group from the normal elderly control group. The field strength at 3T, as well as increased scan resolution for accurate quantification in small brain regions may have contributed to the additional positive findings that complement other MRI-derived measures of disease burden in AD. In addition, this automated method entirely removes operator induced measurement errors, which may contribute to both longitudinal and multi-center studies for the standardization of quantification.

90 A longitudinal study on age-related changes of T1rho relaxation in rat brain
Feng Zhao1, Jing Yuan1, Tian Jiu2, Gang Lu2, Queenie Chan3, Wai-Sang Poon2, and Yi-Xiang Wang1
1Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, 2Division of Neurosurgery, Department of Surgery, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, 3Philips Healthcare, Hong Kong

An alternate MRI contrast mechanism, T1rho relaxation, has been suggested as a sensitive biomarker to detect Alzheimer¡¯ disease and Parkinson¡¯s disease in patients. However, whether normal brain aging is associated with brain T1rho relaxation change remains unknown. In this study, we longitudinally measured T1rho values in the bilateral thalamus, hippocampus and cortices of 18 male Sprague-Dawley rats at 5, 8, 10 and 15 months old. A trend of T1rho value rising in these rat brain regions following aging was found.

91 Magnetization Transfer Contrast MRI as a Diagnostic Tool for Alzheimer’s Disease
Carlos J Perez-Torres1,2, and Robia G Pautler1,2
1Interdepartmental Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, Texas, United States, 2Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas, United States

Early diagnosis of Alzheimer’s Disease (AD) remains a critical challenge for the management of this disease. Most work has focused on non-invasive imaging of amyloid beta plaques. However, it is known that amyloid neurotoxicity begins before plaque formation, so techniques are needed that can identify AD before plaque formation. In this work, we apply Magnetization Transfer Contrast (MTC), an MRI methodology already in use clinically. Our results show an increase in MTC signal that predates plaque formation in the Tg2576 mouse model of AD. The source of the MTC signal appears to be Tau and not the expected amyloid beta.

3760.   92 Quantitative 7T Detection of Gadoteridol in the Ventricles of the Aging Human Brain
Valerie C. Anderson1, David P. Lenar1, Phillip C. Berryhill1, Joseph F. Quinn2, Jeffrey A. Kaye2, and William D. Rooney3
1Neurological Surgery, Oregon Health & Science University, Portland, OR, United States, 2Neurology, Oregon Health & Science University, Portland, OR, United States, 3Advanced Imaging Research Center, Oregon Health & Science University, Portland, OR, United States

1H2O R1 values were determined in the superior lateral ventricles of 34 healthy older subjects (68 plus-or-minus sign 6 yrs; 13 M, 21 F) at 7T before and 3 times (within 50 min) after gadoteridol (CR) administration. Fractional CSF volume was determined by segmentation of structural T1-w images. A significant inverse correlation of pre-CR R1 values with ventricular volume was observed. R1 values increased at each time point after injection of CR, confirming that administration of CR increases R1 in the ventricles of the human brain. R1 values after CR administration were increased significantly more in women than men.

3761.   93 Postmortem MRI Reveals Alterations in T2 Associated with Histopathologically Verified Alzheimer’s Disease and other Pathology in the Elderly Human Brain
Robert Dawe1, Julie Schneider1, David Bennett1, and Konstantinos Arfanakis1,2
1Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, United States, 2Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, United States

Using postmortem MRI, we mapped T2 in 228 fixed cerebral hemispheres. After spatial registration, we performed voxelwise analysis of covariance to identify T2 alterations associated with histopathologically confirmed Alzheimer’s disease and other neuropathology among the elderly. T2 prolongation was observed in association with Alzheimer’s disease in the white matter of the temporal, frontal, and parietal lobes. T2 prolongation in association with gross infarcts was observed throughout the majority of white matter and was most intense in the frontal lobe. This study demonstrates the utility of postmortem T2 mapping and provides candidates for MRI-based biomarkers of disease.

3762.   94 Semi-automatic detection of cerebral microbleeds on clinical 3.0T T2*-weighted images using the radial symmetry transform
Hugo J. Kuijf1, Manon Brundel2, Max A. Viergever1, Geert Jan Biessels2, and Koen L. Vincken1
1Image Sciences Institute, University Medical Center Utrecht, Utrecht, Netherlands, 2Department of Neurology, Rudolf Magnus Institute of NeuroScience, UMC Utrecht

The current standard for cerebral microbleed detection is visual rating, which is laborious and has limited reproducibility. Semi-automated methods for detection of microbleeds on clinical images have been suggested before, but suffer from a large number of false positives. In this study, we present a method for microbleed detection based on the radial symmetry transform. This results in a high sensitivity of 75% and a limited number of false positives, requiring just two minutes of rater time to censor them. Furthermore, the method outperforms other known methods in terms of specificity.

3763.   95 White matter microstructure in a healthy population aged 50-65; automated tractography method and TBSS.
Live Eikenes1, Eelke Visser2, and Asta Håberg1
1Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway, 2Donders Institute for Brain, Cognition and Behaviour, Centre for Cognitive Neuroimaging, Radboud University Nijmegen, Nijmegen, Netherlands

White matter (WM) microstructure were studied at the population level in a cohort of 1006 healthy participants (50-65 years) using a new automated tractography method and tract-based spatial statistics (TBSS). The tractography results demonstrated that mean fractional anisotropy (FA) and volume of corpus callosum was higher in males compared to females. TBSS showed decreased FA in large areas of the white matter with increasing age, and higher FA in females than males in the occipital lobe, and higher FA in males than females in the deep central WM structures and in association tracts in the frontal and temporal lobes.

3764.   96 T2-weighted MRI increases machine learning accuracy in Alzheimer's disease
L. Z. Diaz-de-Grenu1, G. B. Williams1, J. Acosta-Cabronero1, J. M. Pereira1, and P. J. Nestor1
1Clinical Neurosciences, University of Cambridge, Cambridge, Cambridgeshire, United Kingdom

Support vector machines (SVM) using T1-weighted images offer moderate accuracy in diagnosing Alzheimer’s disease (AD). Recent work suggests, however, that T2-weighted scans may contain more pathologically relevant information. This study, therefore, tested if T2 data could improve SVM classification. T1 and T2 were compared in whole-brain images and regions of interest (ROI) known to be affected in AD. An ROI focused on the mesial temporal lobe (known to be atrophic) yielded similar accuracy for T1 and T2 (both 88.5%), however adding ROIs known to be rich in beta-amyloid improved diagnostic accuracy (92.3%) but only when using T2 data.