Bassem Hiba¹, Bader Chaarani¹, M. C. Beauvieux¹, G Rafard¹, Michèle Allard², Alan Stephant¹, Jean Michel Franconi¹, and Jean Louis Gallis^1
1UMR 5536 RMSB, CNRS-UB2, Bordeaux, France, ²UMR 5231, CNRS-UB2, Bordeaux, France

The aim of this work is to follow-up the earliest brain changes from the onset of vitamin A deprivation (VAD) in a rat model of brain degenerative process, using diffusion tensor imaging and anatomical MRI. 4 rats with VAD and 4 control rats were followed once a week along the first 6 weeks of VAD. This study demonstrated that the growth of total brain, striatum and hippocampus decreases from the 1st week, that dramatic increases in ventricular volumes occured at the 4th week and a significant decrease of the fraction anisotropy was detected only on the 6th week of VAD.

Rachelle Berger¹, Matthew Fenty², Michiyo Iba³, Virginia M.-Y. Lee³, John A. Detre⁴, and Ari Borthakur^2
1Biochemistry & Molecular Biophysics, University of Pennsylvania School of Medicine, Philadelphia, PA, United States, ²CMROI, Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, PA, United States, ³CNDR, Department of Pathology & Lab Medicine, University of Pennsylvania School of Medicine, ⁴CfN, Department of Neurology, University of Pennsylvania School of Medicine

This study measures the efficacy of T1 as a biomarker for tau pathology in the PS19 transgenic (Tg) mouse model of Alzheimer’s Disease (AD). While previous work has utilized only amyloid models of AD pathology, this animal model provides tantalizing possibility for investigating hyperphosphorylated tau protein that leads to intracellular neurofibrillary tangles using MRI for the first time. A significant decrease in T1 relaxation time was measured in Tg mice brains relative to age-matched wild-type mice. The current study will generate crucial baseline values that can be assessed in this animal model in longitudinal studies that test novel therapeutic agents.

Greetje Vanhoutte¹, Sandra Pereson², Bob Asselbergh², Christine Van Broeckhoven², and Anne-Marie Van der Linden^1
1Biomedical Sciences, Bio-Imaging Lab, University of Antwerp, Antwerp, Antwerp, Belgium, ²Molecular Genetics, VIB and Institute Born-Bunge, University of Antwerp, Antwerp, Antwerp, Belgium

In vivo detection of the amyloid deposits in the brain would be beneficial in terms of AD diagnosis and therapy follow-up. The presence of amyloid deposits results in an increasing number of diffusion barriers and higher microstructural complexity. Our DKI results reinforce the hypothesis that DKI is a more sensitive technique than its predecessor DTI to depict changes in brain regions with amyloid deposits. In this in vivo study we observed higher kurtosis values in the brains of APPPS1 mice as compared to littermates.

Alia Alia¹, Haud Noémie², Firat Kara¹, and Adam Hurlstone^2
1Leiden Institute of Chemistry, Leiden University, Leiden, South holland, Netherlands, ²University of Manchester, United Kingdom

Zebrafish is increasingly used as model organism for understanding various brain diseases including neurodegenerative disorders. Very recently the first zebrafish model for Cystic Leukoencephalopathy has been developed in which RNASET2 gene has been mutated. In this study we applied high resolution µMRI to visualize neurodegeneration in RNASET2 deficient zebrafish. T2-weighted MR imaging showed that RNASET2 deficient zebrafish exhibit frequent white matter anomalies which were scattered throughout the brain. T2 relaxation measurements suggest that theses lesions may be filled with CSF. Our results suggest that zebrafish model of Cystic Leukoencephalopathy develops similar lesions as found in human patients and show that µMRI can be successfully used to visualize neurodegeneration in zebrafish.

Firat Kara¹, Kristin Möbius¹, Mark A van Buchem², Huub JM de Groot¹, Reinhard Schliebs³, and Alia Alia^1,4
1Leiden Institute of Chemistry, Leiden University, Leiden, South holland, Netherlands, ²Department of Radiology, Leiden University Medical Centrum, Leiden, South holland, Netherlands,³Department of Neurochemistry, University of Leipzig, Leipzig, Germany, ⁴Department of Radiology, Leiden University Medical Centrum, Leiden, Netherlands

Glucose uptake and metabolism has been shown to be impaired during Alzheimer’s disease and is suggested to be an important cause of neurodegeneration. However the cause of impairment of glucose uptake/metabolism is AD brain and its correlation with plaque deposition is not clear. In this study, we longitudinally monitored, the change in glucose level in APPTG2576 mouse model of AD using in vivo MRS in conjunction with µMRI and ex vivo HR-MAS ¹H MRS. Our results indicate that decline in glucose level occur primarily in plaque affected areas of the brain of APPTG2576 mice and show a temporal correlation between glucose decline and plaque deposition in AD brain.

Anne Bertrand^1,2, Umer Khan², Dung Minh Hoang², Dmitry Novikov², Pavan Krishnamurthy³, Hameetha Banu Rajamohamed Sait³, Benjamin Winthrop Little², Einar M Sigurdsson³, and Youssef Zaim Wadghiri^2
1URA CEA-CNRS 2210, MIRCen, Fontenay-Aux-Roses, France, ²Radiology, NYULMC, New York, United States, ³Physiology & Neuroscience, NYULMC, New York, United States

Our aim was to study in vivo the neuronal transport in a mouse model of tauopathy, using manganese-enhanced MRI (MEMRI). We show that 1) JNPL3[P301L] mice display a progressive impairment of neuronal transport with aging; 2) the degree of neuronal transport impairment is correlated with the level of tauopathy in neurons. Thus, MEMRI provides a useful biomarker that can be used during the pre-clinical evaluation of new drugs against Alzheimer’s disease.

Malgorzata Marjanska¹, Stephen D Weigand², Geoffry L Curran², Thomas M Wengenack², Joseph F Poduslo², Michael Garwood¹, and Clifford R Jack, Jr.^2
1Radiology, University of Minnesota, Minneapolis, MN, United States, ²Mayo Clinic College of Medicine, Rochester, MN, United States

MRS was assessed as a non-invasive outcome measure capable of detecting metabolic alterations following passive immunization in a transgenic mouse model of Alzheimer’s disease (AD). Treatment of transgenic AD mice with either of two anti-A antibody regimes that have previously been demonstrated to reduce amyloid plaque load slowed the rate at which mIns normally increases in transgenic AD mice (APP-PS1) in a multi-dose treatment paradigm. ¹H MRS may provide an in vivo measure of anti-A therapeutic efficacy in pre-clinical studies.

Dung Minh Hoang¹, Jing Yang², Lindsay K Hill¹, Wai Tsui³, Yanjie Sun², Yongsheng Li², Mony De Leon³, Thomas Wisniewski^2,3, and Youssef Zaim Wadghiri^1
1Radiology, NYU School of Medicine, New York, NY, United States, ²Neurology, NYU School of Medicine, New York, NY, United States, ³Psychiatry, NYU School of Medicine, New York, NY, United States

Amyloid β (Aβ) plaques are one of the pathological hallmarks of Alzheimer’s disease (AD). Their visualization in the brain is very important to monitor AD progression and to evaluate the efficacy of therapeutic interventions. Numerous studies have investigated the visualization of Aβ plaques using MRI through endogenous detection both in human and in mouse brains. In the present study, we examined whether the use of ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles, chemically coupled with Aβ1-42 peptide along with mannitol through femoral intravenous injection can be effective to detect individual plaques using in vivo µMRI and map the amyloid burden throughout the brain.

Thomas Kaulisch¹, Holger Rosenbrock², and Detlef Stiller^1
1In-Vivo Imaging, Target Discovery Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany, ²CNS Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany

Acetylcholinesterase inhibitors (AChEI) are used for the treatment of mild cognitive impairment (MCI) symptoms in Alzheimer’s disease. Pharmacological MRI (phMRI) can be used to study the dose-response relationship of a pharmacological challenge in the brain. The AChEI donepizil was studied with an rCBV-based MR read-out in rats at two doses (0.2 and 0.5 mg/kg) and compared to challenge with nicotine or the carboanhydrase inhibitor acetazolamid (ACZ); the latter testing the cerebral vascular reserve. A clear dose-response relation was observed being most pronounced in cortical regions. High dose of donepezil yielded changes in rCBV nearly reaching the vascular reserve.

Sandhitsu Das¹, Brian Avants¹, John Pluta¹, Caryne Craige¹, Michael Weiner², Susanne Mueller², and Paul Yushkevich^1
1PICSL, Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States, ²VA Medical Center, University of California at San Francisco, San Francisco, CA, United States

We present the first attempt at measuring longitudinal atrophy rates within the subfields of the hippocampal formation from focal in vivo T2-weighted MRI (HF-MRI). Commonly used T1-weighted structural MRI does not have sufficient intensity contrast to distinguish subfields. In HF-MRI, on the other hand, subfields are distinguishable, but the image is highly anisotropic with high in-plane resolution in slices oriented perpendicular to the long axis of the hippocampus and thick slices -- this poses certain methodological challenges in processing HF-MRI data. We carefully adapt existing techniques to address these challenges and show that significant effects can be measured in a cohort of cognitively impaired patients in subfields such as CA1.

Keith R Thulborn¹, Debra Fleischman², R Shah², Ian C Atkinson¹, and Aiming Lu^1
1Center for Magnetic Resonance Research, University of Illinois at Chicago, Chicago, IL, United States, ²Rush Alzheimer's Disease Clinic, Rush University Medical Center, Chicago, IL

Alzheimer’s disease (AD) is a devastating neurodegenerative disease for which there is no early detection, no cure and no long lasting intervention. Early changes in cell density may offer an opportunity for detecting preclinical AD, a necessary first step design and evaluate interventions without the use of clinical disease as an outcome measure. We report on the use of quantitative sodium MR imaging for detecting cell density changes in the hippocampal regions of subjects with mild probable AD and mild cognitive impairment that can progress to AD.

Hubert Martinus Fonteijn¹, Matt J Clarkson², Marc Modat¹, Josephine Barnes², Manja Lehmann², Sebastien Ourselin¹, Nick C Fox², and Daniel C Alexander^1
1Computer Science, Centre for Medical Image Computing, London, United Kingdom, ²Institute of Neurology, Dementia Research Centre, London, United Kingdom

This abstract introduces a novel method for studying disease progression using cross-sectional data. The model describes disease progression as a series of events and treats each data point as a snapshot of this series. We calculate the probability that an event has happened and use a MCMC algorithm to construct plausible series of events from this probability. We demonstrate our model on serial T1 MRI data from a familial Alzheimer’s disease cohort. We calculate regional atrophy using non-linear registration methods and show progression of atrophy on a much finer level than previous studies, confirming progression patterns from pathological studies.

Robert J Dawe¹, Julie A Schneider², David A Bennett², and Konstantinos Arfanakis^1
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

Postmortem MRI of the human brain allows for comparison of imaging findings with histopathologic data, providing a unique opportunity to evaluate the sensitivity of new MRI techniques to tissue changes related to Alzheimer’s disease (AD) and other neurodegenerative diseases. The purpose of this work was to investigate differences in T2 relaxation times among postmortem brain specimens with low, intermediate, and high likelihood of AD, assessed histopathologically, according to the National Institute on Aging (NIA)-Reagan Institute criteria. T2 elevation was detected in periventricular and subcortical white matter regions, and T2 depression was detected in the globus pallidus and putamen.

Wenzhen Zhu¹, and Lingyun Zhao^2
1Department of Radiology, Tongji Hospital,Tongji Medical College, Wuhan, Hubei Province, China, People's Republic of, ²Department of Radiology, Tongji Hospital,Tongji Medical College

This study initially investigate the correlation of increased brain iron accumulation with the severity of cognitive impairment in patients with Alzheimer’s disease using advanced quantitative R2' mapping. The results revealed that R2' is a reliable parameter in measuring brain iron deposition in AD patients; Furthermore, regional R2' and brain iron concentration, especially which of bilateral hippocampus and parietal cortex, were significantly positive correlated with the severity of cognitive impairment, indicating that R2' can be used as an imaging marker to evaluate disease progression. R2' technique might provide exciting potential applications to the diagnosis, longitudinal monitoring, and therapeutic development for AD.

Jung Wook Suh¹, Hongzhi Wang¹, Sandhitsu Das¹, Brian Avants¹, and Paul A Yushkevich^1
1PICSL, Radiology, University of Pennsylvania, Philadelphia, PA, United States

Hippocampal volume is arguably the most widely accepted MRI-based Alzheimer’s disease (AD) biomarker. We provide a highly reliable, open-source, validated turnkey software solution for automatic measurement of hippocampal volume and atrophy in T1 MRI data. Such tool will enable rapid analysis of imaging data for disease progression and treatment effect evaluation in clinical applications.

Carlos J. Pérez-Torres^1,2, and Robia G Pautler^1,2
1Interdepartmental Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, Texas, United States, ²Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas, United States

Alzheimer’s disease (AD), the most common form of dementia, is an incurable and terminal progressive neurodegenerative disease. Accumulation of amyloid peptide is an early event in the disease and is one of the classical pathological hallmarks of AD. Magnetization Transfer Contrast (MTC) is a Magnetic Resonance Imaging (MRI) technique to specifically detect changes in macromolecule concentration. In this work, we show that MTC MRI is sensitive to large changes in amyloid as evidenced in a mouse model of advanced AD.

Elisa Scola¹, Federica Agosta², Elisa Canu², Lidia Sarro², Alessandra Marcone³, Chiara Cerami³, Giuseppe Magnani⁴, Francesca Caso⁴, Stefano Francesco Cappa^3,5, Massimo Filippi², and Andrea Falini^1,6
1Neuroradiology - CERMAC, San Raffaele Scientific Institute, Milan, Italy, ²Neuroimaging Research Unit, Scientific Institute and University San Raffaele Hospital, Milan, Italy, ³San Raffaele Turro Hospital, Department of Clinical Neurosciences, Milan, Italy, ⁴Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience, Scientific Institute and University San Raffaele Hospital, Milan, Italy, ⁵Vita Salute University and Department of Clinical Neurosciences, San Raffaele Scientific Institute, Milan, Italy, ⁶Vita Salute University, San Raffaele Scientific Institute, Milan, Italy

The aim of this study was to assess the patterns of white matter (WM) tract damage in behavioural variant frontotemporal dementia (bvFTD) and primary progressive aphasia (PPA). WM damage was investigated globally in a voxel-by-voxel analysis as well as in specific fibre tracts. DT MRI demonstrated specific patterns of WM damage in bvFTD and PPA patients. Although WM abnormalities mirrored the patterns of grey matter (GM) atrophy, diffusivity changes were also identified in more posterior brain regions, which may be atrophied later in the course of the disease.

David Raffelt^1,2, Stephen Rose³, J-Donald Tournier^4,5, Robert Henderson⁶, Stuart Crozier², Olivier Salvado¹, and Alan Connelly^4,5
1The Australian E-Health Research Centre, CSIRO, Brisbane, QLD, Australia, ²Biomedical Engineering, School of ITEE, University of Queensland, Brisbane, QLD, Australia, ³Centre for Advanced Imaging, University of Queensland, Brisbane, QLD, Australia, ⁴Brain Research Institute, Florey Neuroscience Institutes (Austin), Melbourne, VIC, Australia, ⁵Department of Medicine, University of Melbourne, Melbourne, VIC, Australia, ⁶Department of Neurology, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia

Motor Neurone Disease (MND) involves progressive degeneration of the motor neurons and is typically fatal within 2-5 years; consequently there is considerable need for neuroimaging biomarkers to aid prognosis and pharmaceutical development. In this work we demonstrate the use of a recently developed measure called Apparent Fibre Density (AFD) to detect differences in MND within pathways related to the motor cortex. In addition to corroborating previous findings in MND, this study demonstrates the clear advantage of using AFD analysis in the context of multiple fibre orientations, by identifying not only the location, but also the orientations along which differences exist.

Seyede Ghazal Mohades^1,2, Esli Struys¹, and Robert Luypaert^2
1VUB, Brussels, Brussels, Belgium, ²MRI, UZ Brussel, Brussels, Brussels, Belgium

This study is aimed to find differences in the structure of white matter of the brain between monolinguals and bilinguals. MR-DTI based tractography is used to track three sets of fibers in the areas that are of interest in linguistic studies (i.e. betwwenBroca’s and Wernicke’s areas, between broca’s area and corpus callosum and from anterior midbody of corpus callosum to primary motor cortex ). The results show that there is significant difference in FA value of fibers connecting Broca’s to Wernicke’s area and also the fibers that connect Broca’s area to corpus callosum between these two groups.

Jhih-Wei He¹, C-M Liu², H-G Hwu², C-C Liu², F-H Lin¹, and W-Y I Tseng^3
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

To understand the relationship between anatomical changes and clinical syndromes in schizophrenia, we used diffusion spectrum imaging (DSI) to compare the general fractional anisotropy (GFA) of the fornix between patients and controls, and explored the correlations between GFA values and PANSS subscores. Significant reduction of GFA in bilateral fornix was found in patients. We also found positive correlations between GFA of right fornix and subscore P7 (Hostility), G8 (Uncooperativeness), and a negative correlation between left fornix and subscore G10 (Disorientation). Our findings demonstrate the usefulness of DSI tractography to investigate the functional relevance of the white matter tracts in schizophrenia.

Robert J. Dawe¹, Julie A Schneider², David A Bennett², and Konstantinos Arfanakis^1,2
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

Diffusion tensor imaging (DTI) of ex vivo human brain specimens offers a unique opportunity for histopathologic verification of in vivo DTI findings. However, DTI data acquired ex vivo may be contaminated by postmortem changes to the tissue’s MR properties. In this work, human brain hemispheres were imaged with DTI over time up to one month postmortem. Mean diffusivity underwent a drastic reduction within one day postmortem. Postmortem fractional anisotropy was initially similar to antemortem values, but decreased substantially within one week postmortem.

Yi-Huan Wu¹, Yu-Chun Lo², Shur-Fen Susan Gau³, and Wen-Yih Isaac Tseng^4,5
1School of Medicine, National Taiwan University College of Medicine, Taipei, Taiwan, ²Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan, ³Department of Psychiatry, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan, ⁴Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan, ⁵Center for Optoelectronic Biomedicine, National Taiwan University College of Medicine, Taipei, Taiwan

Attention deficit/hyperactivity disorder (ADHD) is one of the most commonly diagnosed neurodevelopmental disorders in childhood. Deficits in neural circuits linking regions of the prefrontal cortex and the striatum (caudate nucleus and putamen) have been postulated to account for the core symptoms in ADHD. Using diffusion spectrum imaging, we found that children with ADHD had lower generalized fractional anisotropy of the fronto-striatal fibers compared with healthy children. This finding implies a disruption in the normal pattern of structural and functional connectivity in fronto-striatal brain regions in children with ADHD.

say Ayala-Soriano¹, Emma Webb², Kiran Seunarine³, Ruth Lions⁴, Tessa Mellow⁴, Michelle O'Reilly⁵, WK Chong⁶, Mehul Dattani⁷, Alki Liasis⁴, and C A Clark^3
1Imaging and Physics, Institute of Child health,Department of Neurosurgery, Great Ormond Street Hospital, London, UK, United Kingdom, ²Imaging and Physics,Institute of Child Health, United Kingdom, ³Imaging and Physics, Institute of Child Health, London, United Kingdom, ⁴Opthalmology, Great Ormond Street Hospital, London, United Kingdom, ⁵Neurosciences, Institute of Child Health, London, United Kingdom, ⁶Neuroradiology, Great Ormond Street Hospital, London, United Kingdom, ⁷Endocrinology, Great Ormond Street Hospital, London, United Kingdom

Optic nerve hypoplasia (ONH) is a congenital abnormality characterised by an underdevelopment of the optic nerve and is the third most common cause of severe visual impairment in children. ONH is a clinical diagnosis only and conventional MRI fails to detect all the cases. Eleven children with ONH aged 2 to 11 and 22 controls were enrolled in the study. TBSS analysis revealed that fractional anisotropy (FA) within the optic radiations was lower bilaterally in patients with ONH compared to controls (p < 0.05). TBSS analysis provided evidence for structural abnormality in the optic radiations in paediatric patients with ONH.

Stephen Rose¹, Kerstin Pannek¹, Andrea Guzzetta², and Roslyn Boyd^3
1Centre for Clinical Research, University of Queensland, Brisbane, Queensland, Australia, ²Department of Developmental Neuroscience, Stella Maris Scientific Institute, Pisa, Italy, ³Queensland Cerebral Palsy and Rehabilitation Research Centre, University of Queensland, Brisbane, Queensland, Australia

Unilateral periventricular brain lesions occurring early during the third trimester of pregnancy are a significant cause of congenital hemiplegia. However, little is known regarding the role of sensorimotor pathways that project directly into the primary motor cortex in controlling paretic hand function. In this study, we introduce an automated structural connectivity approach for correlating asymmetry indices derived for the corticospinal tracts and spinothalamic-corticothalamic pathways with clinical measures of paretic hand function. Our findings support the concept that preservation of afferent sensorimotor thalamic pathways has more influence on motor function control of the paretic hand than preservation of corticospinal tracts.

Samuel Groeschel¹, J.-Donald Tournier², Gemma Northam³, Torsten Baldeweg³, John Wyatt⁴, Brigitte Vollmer^5,6, and Alan Connelly^2
1Experimental Pediatric Neuroimaging and Developmental Medicine & Child Neurology, University Children's Hospital, Tuebingen, Germany, ²Brain Research Institute, Melbourne, Australia, ³UCL Institute of Child Health, London, United Kingdom, ⁴UCL Hospitals, London, United Kingdom, ⁵Karolinska Institute, Stockholm, Sweden, ⁶University of Southampton, United Kingdom

The objective of the present study is to investigate diffusion parameters along motor pathways in adolescents born preterm. HARDI data of 45 preterm adolescents and 31 term-born controls were analysed using Constrained Spherical Deconvolution and a probabilistic tracking algorithm. The major finding in this study is that disruption of WM microstructure in a single fibre region with resulting higher radial diffusivity leads to lower FA, whereas selective disruption of one fibre population in a crossing fibre region may lead to higher FA. These findings challenge the common simplistic interpretation of FA as a measure of WM tract integrity.

Philip Julian Broser¹, Faraneh Vargha-Khadem², and Chris A. Clark^3
1Imaging and Biophysics Unit, UCL Institute of Child Health, London, London, United Kingdom, ²Developmental Cognitive Neuroscience Unit, UCL Institute of Child Health, ³Imaging and Biophysics Unit, UCL Institute of Child Health, London, United Kingdom

In this study we developed a new method to analyze the thalamus and its constituent substructures based on probabilistic tractography. Probabilistic tractography is an MRI technique that estimates the likelihood of connection between two points in the brain by sampling the distribution of greatest diffusion directions in each voxel of the brain image. In contrast to the previously published methods, which are applied at the group level, our method can be used to analyze the thalamic substructures in individual datasets. The method was applied to a MRI data set of 43 healthy children. Using this data set and our method we compiled a standard map of the thalamic substructures and compared this with existing atlases. We envisage in future that this standard map and the proposed method will be useful for studies of thalamic damage, particularly in children, which can be applied in individual cases. This should make possible future studies of thalamic connectivity with correlation to neurological dysfunction.

Monica Bucci¹, Kelly Westlake¹, Christopher Nguyen¹, Bagrat Amirbekian¹, Srikantan Nagarajan¹, and Roland G Henry^1
1Department of Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States

Structural remodeling of white matter may occur in motor recovery after stroke. We mapped the structural connectivity of the network of hand motor function, by combining magneto-encephalography, with HARDI diffusion MRI, in 4 controls and 4 stroke subjects before and after a robotic rehabilitation intervention. In 4 control subjects we successfully mapped the structural connectivity of the motor network. When tracking in stroke patients we observed improved structural connectivity for the ipsilesional M1 connections to contralateral M1 and to the ipsilesional ventral PMC in the patient with the best recovery score and different degrees of structural changes in the others.

Maria Luisa Mandelli¹, Monica Bucci¹, Eduardo Caverzasi¹, Mehul Sampat¹, Grace Yoon², Patricia P Katz², Laura Julian², and Roland G Henry^1
1Department of Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States, ²Department of Medicine, UCSF, San Francisco, CA, United States

Systemic Lupus Erythematosus is an autoimmune disorder affecting the central (CNS) nervous system often occurring in the subcortical white matter. Diffusion Magnetic Resonance Imaging is an imaging tool of choice to detect subcortical white matter damage. The purpose of this study is to investigate whether Mean Diffusivity (MD), Fractional Anisotropy (FA), and eigenvalues in the white matter of the brain of Systemic Lupus Erythematosus (SLE) patients differ from those of healthy controls. SLE patients showed a significant decrease on FA (P=0.010) and on Axial Diffusivity (λ1) (P=0.017) measures compared to control subjects in the normal appearing white matter.

Ona Wu¹, Leonardo M Batista², Thomas Benner¹, A Gregory Sorensen¹, Karen L Furie², and David M. Greer^2,3
1Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States, ²Department of Neurology, Massachusetts General Hospital, Boston, MA, United States, ³Department of Neurology, Yale University, New Haven, CT, United States

Cardiac arrest survivors who were still comatose 3 days post-resuscitation were analyzed to investigate the utility of diffusion tensor imaging in identifying patients with a good chance of long-term recovery, defined by 6-month modified Rankin Scale score <=4. Imaging studies performed more than 72 hours from resuscitation showed significant differences in terms of good and poor outcome. Studies performed earlier than 72 hours were inconclusive between patients with good and poor outcome. For patients who are still in a comatose state, late imaging can provide useful information regarding the patient’s chances for recovery.

Jung-Hoon Lee^1,2, Sang-Young Kim¹, Kyung-Bae Lee^1,2, Do-Wan Lee¹, Youn-Bong Choi², and Bo-Young Choe^1
1Department of Biomedical Engineering, The Catholic University of Korea, Seoul, Korea, Republic of, ²Department of Radiology, Kyunghee University Medical Center, Seoul, Korea, Republic of

The purpose of this study was to determine if changes in fractional anisotropy (FA) and the apparent diffusion coefficient (ADC) of Broca's and Wernicke's areas could be observed in patients with Parkinson's disease (PD) by diffusion tensor imaging (DTI). The FA values in Broca's and Wernicke's areas of patients with PD were significantly decreased compared to controls. In addition, fiber-tractography helped to visualize the connection of nerve fibers in language areas of the left hemisphere. These results suggest that neurodegenerative changes occur in the language areas of patients with PD.

Seong-Eun Kim¹, John Rose², Ji Kang Park³, Eun-Kee Jeong¹, John Rock Hadley¹, Emilee S Minalga¹, and Dennis L Parker^1
1Utah Center for Advanced Imaging Research, Department of Radiology, University of Utah, Salt Lake City, Utah, United States, ²Department of Neurology, University of Utah, ³Department of Radiology, Jeju National University Hospital, Jeju, Korea, Republic of

DT parameters measured by DTI, such as FA enable more sensitive and specific detection and monitoring of structural changes caused by pathology such as edema and inflammation which occurs in acute optic neuritis. However, in vivo DTI of the optic nerve (ON) using the conventional 2Dsingleshot EPI is generally very challenging because of its small size and the presence of magnetic susceptibility artifacts. In this work we present the measurement of DT parameters such as mean diffusivity (MD), fraction anisotropy (FA), axial and radial diffusivities of normal and pathological ONs obtained with 2D ss-IMIV DWEPI and a dedicated 20-channel coil.

Peter Raab¹, Kathrin S Blum¹, Anita B Tryc², Annemarie Goldbecker², Ali Tabesh³, Heinrich Lanfermann¹, and Karin Weißenborn^2
1Neuroradiology, Hannover Medical School, Hannover, Germany, ²Neurology, Hannover Medical School, Hannover, Germany, ³Radiology, New York University, New York, United States

Neuropsychological impairments in liver disease often present as deficits in attention, memory and higher executive function. Different liver diseases like HCV infection as well as liver cirrhosis can lead to similar symptoms. Diffusion Kurtosis Imaging and 1H-MR-Spectroscopy were used to look for structural brain differences in these two types of liver disease, compared to normal data. The results for cirrhosis patients are consistent with increased water content due to the altered ammonia metabolism, whereas in HCV patients results indicate consistency with the idea of increased microglial activation in the basal ganglia due to the known brain invasion by the hepatitis-C-virus.

Zhi Wang¹, William FC Baar¨¦^2,3, Ron Kupers², Tim Dyrby², Olaf Paulson², Min Chen¹, Cheng Zhou¹, and Maurice Ptito^2
1Radiology, Beijing Hospital, Beijing, Beijing, China, People's Republic of, ²Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital, Hvidovre, Denmark, ³Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark

We extended further our previous results by exploring here the whole brain white matter organization in a large cohort of congenital blindness(CB) compared to normal sight controls(NS) by combining VBM-DARTEL and DTI. All components of the visual system were reduced, especially the bilateral superior colliculi. All structures belonging to the visual system showed significant reductions of anatomical connectivity. Eleven of thirteen NS showed the entire visual-related fiber tracts. On the contrary, only 2 of 13 CB demonstrated the similar fiber tracts.

Maarten Vaessen^1,2, Jacobus Jansen^1,2, Marielle Vlooswijk³, Paul Hofman^1,2, Marian Majoie^3,4, Albert Aldenkamp^2,4, and Walter Backes^1,2
1Radiology, Maastricht University Medical Centre, Maastricht, Netherlands, ²School for Mental Health and Neurosciences, Maastricht University, Maastricht, Netherlands, ³Neurology, Maastricht University Medical Centre, Maastricht, Netherlands, ⁴Epilepsy Centre Kempenhaeghe, Heeze, Netherlands

The relation between white matter connectivity abnormalities and cognitive decline in chronic epilepsy was investigated using graph theoretical network analysis on tractography derived volumetric structural network. Clustering and path lengths appeared abnormal in epilepsy patients with cognitive impairment and were strongly correlated with IQ and IQ discrepancy scores. These results suggest that epilepsy interferes with structural networks that play a role in cognitive impairment.

Madhura Ingalhalikar¹, Drew Parker¹, Timothy P.L. Roberts², and Ragini Verma^1
1Section of Biomedical Image Analysis, Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States, ²Lurie Family Foundations MEG Imaging Center, Childerns Hospital of Philadelphia, Philadelphia, PA

This work presents a paradigm for generating a pathology based marker of language impairment (LI) in Autism Spectrum Disorder (ASD). This is achieved by combining MEG and DTI features in a pattern classifier. These classifiers, in addition to group separation have a potential to quantify the degree of LI by assigning an abnormality score to each subject. Furthermore, the ranking of features gives a physiological insight into the pathology. A 3-way classification between LI-ASD, non-LI-ASD and typically developing (TD) controls was achieved with an average accuracy of 71.69% providing better understanding of LI than just using individual modalities.

Harini Eavani^1,2, Luke Bloy^2,3, John Herrington¹, Timothy L. Roberts⁴, Robert T Schultz¹, and Ragini Verma^2
1Center for Autism Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States, ²Section of Biomedical Image Analysis, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States, ³Department of Bioengineering, University of Pennsylvania, ⁴Lurie Family Foundations MEG Imaging Center

High Angular Resolution Diffusion Imaging(HARDI) is a new diffusion imaging protocol that can model complex white-matter better than Diffusion Tensor Imaging(DTI), which cannot delineate fiber-tracts across regions with fiber-crossings. In this study we establish the superiority of HARDI over DTI in identifying tracts by tracking the ArcuateFasciculus(AF) in a clinical population of children(8-18years) with autism. Results show that the AF is tracked significantly better in HARDI than DTI in all subjects and is closer to its anatomical definition. This establishes the feasibility of HARDI acquisition in clinical populations and can provide novel insight into the disease with subsequent tract-based analysis.

Jeffrey I Berman^1,2, and Timothy P. L. Roberts^1,2
1Radiology, Children's Hospital of Philadelphia, Philadelphia, PA, United States, ²Radiology, University of Pennsylvania, Philadelphia, PA, United States

It is necessary to develop robust methods of delineating the entire auditory radiation for quantitative studies in children with autism or language impairments. This work demonstrates the consistent ability of high angular resolution diffusion imaging (HARDI) fiber tracking to delineate the full length of the auditory radiation in a population of children. Diffusion MR was acquired from 6 children with autism spectrum disorder and 3 control children on a 3T Siemens scanner. The ability of HARDI and DTI fiber tracking to delineate the full auditory radiation were compared. HARDI fiber tracking successfully delineated the auditory radiation at a significantly higher rate than DTI fiber tracking.

Johanna Mårtensson^1,2, Markus Nilsson², Christina Elfgren³, Maria Landqvist³, Freddy Ståhlberg^2,4, Christer Nilsson³, Danielle van Westen^1,4, and Jimmy Lätt^1
1Center for Medical Imaging and Physiology, Lund University Hospital, Lund, Skane, Sweden, ²Department of Medical Radiation Physics, Lund University Hospital, Lund, Skane, Sweden, ³Geriatric Psychiatry, Department of Clinical Sciences, Lund University Hospital, Lund, Skane, Sweden, ⁴Department of Diagnostic Radiology, Lund University Hospital, Lund, Skane, Sweden

We present a method for spatial evaluation of MRI tractography data based on track co-registration using anatomical landmarks. The feasibility for clinical use was tested in a patient group suffering from semantic dementia. The analysis pinpointed specific areas of the track bundle where differences existed between the patient and healthy control group.

Cheuk Ying Tang^1,2, Emily Lauren Eaves¹, Kristen Dams-O'Connor³, Lap Ho⁴, David Carpenter¹, Johnny Ng¹, Wayne Gordon³, and Giulio M Pasinetti^2,4
1Radiology, Mount Sinai School of Medicine, New York, New York, United States, ²Psychiatry, Mount Sinai School of Medicine, New York, New York, United States, ³Rehabilitation Medicine, Mount Sinai School of Medicine, New York, New York, United States, ⁴Neurology, Mount Sinai School of Medicine, New York, New York, United States

Atrophy of the corpus callosum (CC) observed after traumatic brain injury (TBI) was assessed using diffusion tensor imaging. Prior to scanning, subjects completed a series of questionnaires to assess their emotional and cognitive functioning. A single severity score was ascertained for each TBI subject. TBI subjects reported lower emotional and cognitive scores and had lower fractional anisotropy (FA) in the CC compared to controls. The severity score negatively correlated with CC FA in the TBI group. This study indicates atrophy of the CC following TBI is due to demyelination and FA may be useful as a biological marker for TBI.

Chieh-En Jane Tseng¹, Wei-An Wang¹, Yu-Chun Arica Lo², Yi-Huan Markus Wu³, Chih-Min Liu⁴, Hai-Gwo Hwu⁴, and Wen-Yih Isaac Tseng^3,5
1Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan, ²Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan, ³Center for Optoelectronic Biomedicine, National Taiwan University College of Medicine, Taipei, Taiwan, ⁴Department of Psychiatry, National Taiwan University Hospital, Taipei, Taiwan, ⁵Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan

The mirror neuron system (MNS) has been hypothesized to be important in imitation and social cognition. Recent fMRI studies have reported MNS deficits in schizophrenia. The purpose of this study is to evaluate the white matter structure between the two areas in which mirror neurons have been identified, namely inferior frontal gyrus and inferior parietal lobule. As compared with the neurotypicals, patients showed no significant difference in generalized fractional anisotropy (GFA) bilaterally. In patients, however, positive correlations were found between the scores of social withdrawal and the GFA bilaterally.

shun qi¹, Hong Yin², feng yun mu³, and Yi Huan^3
1xijin hospital,the fourth military medical university, xi'an, shaanxi, China, People's Republic of, ²xijing hospital, China, People's Republic of, ³xijing hospital

Previous studies indicated that there were regional changes in the white matter and grey matter in amblyopia and that can be detected by the diffusion tensor imaging (DTI) and the high-resolution MRI image. However, the exact relationships between cortical thickness of visual cortex and integrity changes of optic radiation (ORs) fibers in anisometropic amblyopia are still unclear. The purpose of this study was to determine whether the changes of the visual cortex associate with integrity changes in the ORs fibers in amblyopia.

Andrew David Nichols¹, Brad Moffat², Helen Danesh-Meyer³, and Andrew H Kaye^4
1Department of Surgery RMH/WH, The University of Melbourne, Parkville, Victoria, Australia, ²Radiology, University of Melbourne, Parkville, Victoria, Australia, ³Ophthalmology, University of Auckland, Auckland, New Zealand, ⁴Department of Surgery (RMH/WH), The University of Melbourne, Parkville, Victoria, Australia

Pituitary tumours represent a significant proportion of intracranial tumours. Growth of pituitary tumours superiorly may cause compression of the optic chiasm and lead to visual failure or visual field deficits. This is potentially avoidable or reversible with surgical intervention. We have performed fMRI and DTI tractography on 7 patients with pituitary tumours to investigate the effects of pituitary tumours on the visual pathway. We believe that there is potential for fMRI and DTI biomarkers to improve and individualise the management of patients with pituitary tumours and influence timing of surgical intervention.

Richard Alan Jones¹, Binjian Sun¹, Robert Clark Brown², and Laura Hayes^1
1Radiology, CHOA, Atlanta, GA, United States, ²Hematology, CHOA, Atlanta, GA, United States

Children with sickle cell disease (SCD) whose brains are normal on conventional MRI often demonstrate neurocognitive impairments. This study uses diffusion tensor imaging to demonstrate differences in the white matter between controls, SCD subjects with radiologically normal brains and SCD subjects with mild gliosis. Extensive changes in the white matter were found for the mean diffusivity with these changes being more widespread in the gliosis group. The majority of the significant changes in the fractional anisotropy were confined to the corpus callosum of the gliosis group. DTI appears to be a sensitive biomarker for assessing the severity of SCD.

Louise Emsell^1,2, Wim Van Hecke^3,4, Camilla Langan¹, Gareth Barker⁵, Alexander Leemans⁶, Stefan Sunaert³, Peter McCarthy¹, Rachel Skinner¹, Dara M Cannon¹, and Colm McDonald^1
1NUI Galway, Galway, Co. Galway, Ireland, ²Developmental & Functional Brain Imaging, Murdoch Children's Research Institute, Melbourne, Victoria, Australia, ³Dept of Radiology, University Hospital Leuven, Belgium, ⁴University of Antwerp, Belgium, ⁵Institute of Psychiatry, London, United Kingdom, ⁶Imaging Sciences Institute, University Medical Center Utrecht, Utrecht, Netherlands

This study sought to identify trait related white matter microstructural abnormalities in 35 prospectively confirmed euthymic bipolar I disorder patients compared to 44 control subjects in a diffusion tensor imaging voxel-based analysis. The results reveal bilateral reductions in fractional anisotropy in the posterior cingulum, callosal splenium, corticospinal tract and cerebellum in patients, with no increases in FA. Illness duration was associated with FA increase in the posterior limb of the internal capsule, however there appeared to be no effect of lithium status on FA. Subtle WM alterations may be present in BD in remission and predispose to illness episodes.

Amritha Nayak¹, Lindsay Walker¹, Carlo Pierpaoli¹, and . the Brain Development Cooperative Group^2
1NICHD, National Institutes of Health, Bethesda, MD, United States, ²www.NIH-PediatricMRI.org

Multicenter DTI studies are becoming increasingly popular for their ability to improve the statistical power of a study by recruiting a large number of subjects. Data from multicenter studies can be heterogeneous in nature when no strict quality control requirements are enforced. We have designed quality assessment criteria to enable the identification of protocol errors and artifacts in multicenter DTI data, and described strategies to remediate the data to make it more compatible between sites.

Bradford A Moffat¹, Jeremy Lim¹, Pramit Phal¹, Christopher Kokkinos¹, and Patricia M Desmond^1
1Radiology, University of Melbourne, Parkville, VIC, Australia

The OR is a very important white matter structure that has proven to be problematic to track using DWI tractography algorithms. The aim of this research was to investigate whether diffusion weighted MRI (DWI) data acquired within a clinical neuroradiology MRI protocol could be used to accurately and robustly visualize the OR. The results of this study show constrained spherical deconvolution methods to have significant performance advantages over traditional tensor based tractography algorithms. Such comparative studies are necessary to validate tractography as clinical tool for neuronavigation and biomarker of axonal integrity.

Samuel Lapere¹, Evelien Carrette², Paul Boon², Kristl Vonck², Xavier De Tiège³, Els Fieremans⁴, Ali Tabesh⁴, Eric Achten¹, and Karel Deblaere^1
1Department of Radiology, Ghent University Hospital, Ghent, Belgium, ²Reference Centre for Refractory Epilepsy, Department of Neurology, Ghent University Hospital, Ghent, Belgium,³Laboratoire de Cartographie Fonctionnelle du Cerveau, ULB-Hôpital Erasme, Brussels, Belgium, ⁴Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY 10016, United States

In patients with refractory epilepsy, diffusion tensor imaging (DTI) can non-invasively provide valuable information on the microstructure and architecture of brain tissue in vivo and can be used to detect and evaluate microstructural alterations of white matter, even beyond the visually abnormal area. However, DTI has an important limitation because it incorrectly assumes that water diffusion in biological tissues occurs in an unrestricted manner and follows a Gaussian distribution, in which the diffusion weighted signal attenuatestion occurs monoexponentially with the strength and duration of the diffusion gradient (i.e. b-value). Diffusion kurtosis imaging (DKI) is an extension of the DTI technique which takes the deviation of restricted water diffusion in biological tissues from the Gaussian distribution (i.e. excess kurtosis characterizing the non-monoexponential signal decay) into account, thereby offering a more sensitive method of detecting subtle microstructural changes in neural tissue, both in the predominantly anisotropic white matter and the more isotropic grey matter . In this study, DKI was used in patients with refractory epilepsy with unknown seizure focus to examine both the region indicated by a preceding magnetoencephalography (MEG) exam (i.e. magnetic dipole cluster) and, if present, the grey matter abnormality visible on anatomical MRI scans. In patients with refractory epilepsy, preliminary results suggest that when using MEG to locate the potential seizure focus, diffusion kurtosis imaging is able to identify microstructural changes in both grey and white matter. Mean, radial and axial kurtosis values in the grey matter abnormality were significantly decreased with respect to the normal-appearing contralateral side.

Patricia E. Litkowski¹, Victor Liu¹, Kyung Peck², Zhigang Zhang³, Kathryn Beal⁴, and Robert J. Young^1
1Radiology, Memorial Sloan-Kettering Cancer Center, New York, New York, United States, ²Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, United States,³Epidemiology & Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York, United States, ⁴Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York, United States

Malignant gliomas are highly invasive tumors with poor clinical outcomes. Current treatment includes uniform radiation around the tumor region. Diffusion tensor imaging (DTI) is a promising modality that may more effectively inform radiation planning, particularly for local tumor growth. We used DTI to construct probabilistic maps based on seed ROI surrounding the tumors. The high-risk areas determined in our analysis showed a strong correlation with the locations of tumor progression, suggesting that DTI may be useful in planning targeted radiation therapy.

Fuchun Lin¹, Yan Zhou², Yasong Du³, Lindi Qin², Zhimin Zhao³, Jianrong Xu², and Hao Lei^1
1State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics & Mathematics, Chinese Academy of Sciences, Wuhan, Hubei, China, People's Republic of, ²Department of Radiology, RenJi Hospital, Jiao Tong University Medical School, Shanghai, China, People's Republic of, ³Department of Child and Adolescent Psychiatry, Shanghai Mental Health Center, Jiao Tong University, Shanghai, China, People's Republic of

Tract-based spatial statistics was used to investigate white matter (WM) integrity in adolescent students with Internet addiction disorder (IAD). Compared to healthy subjects, IAD adolescent students show has abnormalities in many white matter regions including the orbital frontal, superior temporal WM, together with several commissural, association, and projection fibers. Moreover, FAs in the left genu of corpus callosum and the left anterior corona radiation were negatively correlated with behavioral features. Our findings suggested that IAD has some common neurobiological mechanisms with substance addictions and diffusion tensor imaging might be valuable in providing data on neurological prognosis for IAD.

Y-C. Shih¹, H-H. Liou², K-C. Chu³, P-Y. Chen⁴, W-M. Huang⁵, F-H. Lin¹, and W-Y. I. Tseng^4,6
1Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan, ²Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan, ³Graduate Institute of Electrical Engineering, National Taiwan University, Taipei, Taiwan, ⁴Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan, ⁵Graduate Institute of Pharmacology, National Taiwan University College of Medicine, Taipei, Taiwan, ⁶Center for Optoelectronic Biomedicine, National Taiwan University College of Medicine, Taipei, Taiwan

In this study we investigated three association fibers including superior fronto-occipital fasciculus, cingulum bundles (CG) and uncinate fasciculus using diffusion spectrum imaging, and characterized the alteration in these association fibers in seven patients with left mesial temporal lobe epilepsy (mTLE) compared to controls. The patients showed increased structural connectivity in all association fibers except the inferior portion of the left CG. Furthermore, the CG changed its asymmetry from leftward to rightward. Our results suggest that the integrity of left CG ipsilateral to mTLE is affected directly. The increased structural connectivity in other tracts implies a mechanism of white matter plasticity.

Manzar Ashtari¹, Carolyn Mcilree², Melissa Naraine³, Laura Cyckowski⁴, Ruth Milanaik³, Li Kan³, Jeffrey Newcorn⁵, Josephine Elia¹, and Andrew Adesman^3
1Children's Hospital of Philadelphia, Philadelphia, PA, United States, ²University of Vermont Medical School, ³North Shore LIJ Health Systems, ⁴Children's Hospital of Philadelphia, ⁵Mount Sinai School of Medicine

This study is relevant to public health by further developing the science base regarding the white matter abnormalities underlying childhood ADHD as well as providing new insights into relationship between dopamine dysfunction and white matter development in ADHD children.

Lorna Harper^1,2, Edward Newman^1,2, Donald Hadley^1,2, and Donald Grosset^1,2
1University of Glasgow, Glasgow, Scotland, United Kingdom, ²Institute of Neurological Sciences, Glasgow, Scotland, United Kingdom

This study aims to validate previous work demonstrating a reduction in fractional anisotropy (FA) measured in the substantia nigra (SN) of Parkinson’s Disease (PD) patients. DTI studies were acquired in twenty patients together with dopamine transporter (DAT) imaging. DAT imaging was used to confirm the clinical diagnosis of PD before correlation between the radioligand uptake in the striatum and FA measured in the SN was investigated. Two of the patients were found not to have PD; however they also demonstrated a reduction in FA. No correlation was found between FA measured in the SN and radioligand uptake in the striatum.

Elin Haf Davies¹, Kiran Seunarine², Ashok Vellodi³, Tina Banks⁴, and Chris A Clark^2
1Metabolics, Institute of Child Health, London, United Kingdom, ²Neuroimaging and Biophysics, Institute of Child Health, London, United Kingdom, ³Metabolic, Great Ormond Street Hospital for Children NHS Trust, London, United Kingdom, ⁴Great Ormond Street Hospital for Children NHS Trust, London, United Kingdom

Gaucher disease is a lysosomal storage disorder. Diffusion Tensor Imaging (DTI) examines brain white matter tracts - expressed as fractional anisotropy (FA), mean diffusivity (MD), axial and radial diffusivity. Tract-based spatial statistics was used to compare DTI parameters in Gaucher patients to age-sex matched controls. Decreased FA and increased MD was observed in Type III patients, primarily in the middle cerebellar peduncle, with increased axial and radial diffusivity. Despite small, diffuse changes in FA and MD throughout the Type I brain, no significant difference is observed in the cerebellar peduncles. This is the first brain DTI study in Gaucher patients.

Hojjatollah Azadbakht¹, David M. Morris¹, Hamied A. Haroon¹, Brandon Whitcher², Julie Snowden³, and Geoff J Parker^1
1Imaging Science and Biomedical Engineering, School of Cancer and Imaging Sciences, University of Manchester, Manchester, United Kingdom, ²Clinical Imaging Centre, GlaxoSmithKline, London, United Kingdom, ³Greater Manchester Neuroscience Centre, Salford Royal Foundation Trust, Manchester, United Kingdom

While current literature has mainly focused on measuring the atrophy of whole brain, global grey and/or white matter (WM), specific lobes or grey matter structures (e.g. the hippocampus), it is likely that atrophy caused by conditions such as Alzheimer’s also affects WM tracts via degenerative processes. If specific tract systems are more prone to atrophy than others, then tractography-guided atrophy measurements may be more sensitive biomarkers of degeneration than less targeted methods. For this purpose, in this work we apply a novel method for quantifying the progression atrophy in Normal-Aged and AD subjects undergoing serial diffusion MRI scans 1-year apart.

Namhee Kim¹, Miriam Hulkower¹, Young Park¹, Tova Gardin¹, Jeremy Smith¹, Craig Branch¹, and Michael Lipton^1,2
1Gruss Magnetic Resonance Research Center, Department of Radiology, Albert Einstein College of Medicine, Bronx, NY, United States, ²Departments of Psychiatry and Behavioral Sciences, The Dominick P Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, United States

Group-wise analyses of DTI show white matter abnormalities in mild traumatic brain injury (mTBI). Due to variation in mechanism of injury, an approach to identifying loci of brain injury in individual subjects is needed to fully understand mTBI pathology and allow clinical diagnostic use of DTI. We propose a refined Z-score analysis of single subject FA data, which accounts for the variance in inference for an individual subject due to potentially high dependence on the composition of the control group. Our results demonstrate the robustness of the technique and its utility in consistently identifying white matter pathology in mTBI.

Torben Schneider¹, Zoltan Nagy², Claudia AM Wheeler-Kingshott¹, Alan J Thomson³, and Patrick Freund^2,3
1Department of Neuroinflammation, UCL Institute of Neurology, London, United Kingdom, ²Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, London, United Kingdom,³Department of Brain Repair & Rehabilitation, UCL Institute of Neurology, London, United Kingdom

We assessed the integrity of the axonal architecture in the spinal cord rostral to a traumatic cervical lesion and explored the relationship between diffusion tensor metrics and clinical disability. FA and AD were lower and MD and RD higher in the cervical cord rostral to the site of injury when compared to controls. In SCI subjects, FA in the cervical cord was positively associated with impaired motor and sensory function in the right lateral cortico-spinal tract. We conclude that spinal atrophy and clinical disability relate to spinal microanatomical sequel of traumatic injury in its chronic phase.

Simon Sean Keller¹, Tobias Ahrens¹, Siawoosh Mohammadi², Gabriel Möddel¹, Harald Kugel³, Bernd Weber⁴, E Bernd Ringelstein¹, and Michael Deppe^1
1Department of Neurology, University of Münster, Münster, Germany, ²Wellcome Trust Centre for Neuroimaging, University College London, United Kingdom, ³Department of Radiology, University of Münster, Münster, Germany, ⁴Department of Epileptology, University of Bonn, Germany

In this diffusion tensor imaging study, we show that patients with temporal lobe epilepsy with unknown cause (TLEu) have significant diffusion abnormalities of temporal lobe structures ipsilateral and contralateral to the side of seizure onset relative to age and sex matched neurologically healthy controls. We further show that bilateral parahippocampal and thalamic abnormalities correlate with the duration of TLEu.

Demian Wassermann¹, Peter Savadjiev¹, Yogesh Rathi¹, Sylvain Bouix¹, Marek Kubicki¹, Ron Kikinis¹, Martha Shenton¹, and Carl-Fredrik Westin^1
1Brigham and Women's Hospital & Harvard Medical School, Boston, Massachusetts, United States

We present a method for cluster-based analysis along white matter tracts. The method shows increased sensitivity with respect to state-of-the-art methods while retaining mathematical soundness. We prove our method on a specific white matter bundle in a population of 18 schizophrenic subjects and 23 healthy controls.