Joint Annual Meeting ISMRM-ESMRMB 2014 10-16 May 2014 Milan, Italy

Normal Brain Anatomy
Monday 12 May 2014
Silver  14:15 - 16:15 Moderators: Marco Catani, M.D., M.R.C.Psych., Feroze B. Mohamed, Ph.D.

14:15 0117.   
Literacy and the Arcuate Fasciculus
Michel Thiebaut de Schotten1,2, Laurent Cohen1, Eduardo Amemiya3, Lucia Braga3, and Stanislas Dehaene4
1Brain and Spine Institute, Paris, France, 2Natbrainlab - Institute of Psychiatry, London, United Kingdom, 3SARAH Network–International Center for Neurosciences and Rehabilitation, Brasilia, Brazil, 4Collège de France, Paris, France

The acquisition of literacy results from an effortful learning process that leads to functional changes in several cortical regions. We explored whether learning to read also leads to anatomical changes within the left intrahemispheric white matter pathways that interconnect these regions. We revealed that the acquisition of literacy is associated with a reinforcement of left temporo-parietal connections whose microstructure predicts overall reading performance and the functional specialization of the Visual Word Form Area. This anatomical magnetic resonance imaging marker may be useful to predict developmental reading disorders.

14:27 0118.   
A Combined High Spatial- and High Angular-Resolution Diffusion MRI Atlas of the Human Brainstem and Thalamus
Evan Calabrese1, Christine Hulette2, and G. Allan Johnson3
1Biomedical Engineering, Duke University, Durham, North Carolina, United States, 2Pathology, Duke University, Durham, North Carolina, United States,3Radiology, Duke University, Durham, North Carolina, United States

Deep brain stimulation (DBS) provides symptomatic relief from a number of otherwise refractory neurologic conditions through stimulation of small structures in the brainstem and diencephalon. As researchers and clinicians continue to investigate new DBS targets, there is a need for accurate 3D maps of brainstem anatomy and structural connectivity. Diffusion MRI can provide important insight, but clinical studies lack the spatial and/or angular (diffusion) resolution needed for detailed mapping. We present a high spatial- and high angular-resolution diffusion MRI atlas of the postmortem human brainstem and thalamus with an emphasis on structural mapping of DBS targets.

14:39 0119.   
Contralateral cerebello-thalamo-cortical pathways with prominent involvement of associative areas in humans in vivo
Fulvia Palesi1,2, Donald Tournier3,4, Fernando Calamante3,4, Nils Muhlert5,6, Gloria Castellazzi2,7, Declan Chard5,8, Egidio D'Angelo2,9, and Claudia A. M. Wheeler-Kingshott5
1Department of Physics, University of Pavia, Pavia, Pavia, Italy, 2Brain Connectivity Center, National Neurological Institute C. Mondino, Pavia, Pavia, Italy, 3The Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, Heidelberg, Australia, 4Department of Medicine, Austin Health and Northern Health, University of Melbourne, Heidelberg, Australia, 5NMR Research Unit, Department of Neuroinflammation, Queen Square MS Centre, UCL Institute of Neurology, London, United Kingdom, 6Department of Psychology, Cardiff University, Cardiff, United Kingdom, 7Department of Industrial and Information Engineering, University of Pavia, Pavia, Italy, 8National Institute for Health Research, UCLH Biomedical Research Centre, London, United Kingdom, 9Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy

In addition to motor functions, growing evidence indicates that in humans the cerebellum plays a significant role in cognition. This is occurs through connections with cerebral associative areas via synapsis in the thalamus. While recognizing that tractography provides an indirect evidence of anatomical connectivity between regions, using advanced diffusion MRI tractography we aimed to characterise the cerebello-thalamo-cortical pathway in terms of functional and anatomical areas touched by streamlines. Almost 80% of the streamlines reached the cerebellar hemispheres on one side and the associative cerebral cortex on the other, suggesting a prominent connectivity and supporting the coevolution of the two structures.

14:51 0120.   Multiple Echo and Inversion Time MPRAGE with Inner Loop GRAPPA Acceleration and Prospective Motion Correction for Minimally Distorted Multispectral Brain Morphometry
Andre J. W. van der Kouwe1, M. Dylan Tisdall1, Himanshu Bhat2, Bruce Fischl1, and Jonathan R. Polimeni1
1Radiology, Massachusetts General Hospital, Charlestown, MA, United States, 2Siemens Healthcare USA, Charlestown, MA, United States

Conventional MPRAGE suffers from blurring in the inner phase encoding direction (between inversions) and readout direction, due to T1 and T2* decay that broadens the point spread functions in these directions, respectively. This can be mitigated by combining multiple GRAPPA accelerated phase encoding blocks and multiple higher bandwidth echoes (shorter readouts that also reduce susceptibility distortion), respectively. This also enables estimation of absolute T1 and T2* times for each voxel. To minimize blurring, real-time prospective motion tracking with EPI volume navigators is included. The resulting generalized MPRAGE sequence provides high quality images for brain morphometry without affecting total acquisition time.

15:03 0121.   Quantitative properties (water content, relaxometry, MT) of the post mortem brain: a baseline for normal tissue
Ana-Maria Oros-Peusquens1 and N. Jon Shah1,2
1INM-4, Research Centre Jülich, Jülich, Germany, 2Department of Neurology, RWTH Aachen University, Aachen, Germany

MRI of fixed tissue is increasingly used to investigate the brain. However, properties of tissue change with fixation. This study investigates post mortem formalin-fixed brains quantitatively in order to provide a baseline for MR parameters characteristic of healthy brain tissue. The variability of several quantitative MRI parameters is characterized in fixed brain tissue obtained from donors unaffected by neurological conditions. Among other parameters, quantitative water content determined non-invasively with MRI is reported on whole human post mortem brains for the first time to our knowledge. Correlations between different parameters were investigated and compared to the same quantities measured in vivo.

15:15 0122.   Visualizing Intrathalamic Structures with Combined Use of MPRAGE and SWI at 7T
Allen Newton1,2, Benoit Dawant3, and Pierre D'Haese3
1Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States, 2Institute of Imaging Science, Vandebrilt University, Nashville, TN, United States, 3Electrical Engineering and Computer Science, Vanderbilt University, Nashville, TN, United States

Visualizing intrathalamic structures anatomically is important for guidance of surgical interventions, as well as validating existing thalamic parcellations from functional connectivity or DTI tractography, though it has proven quite difficult. Recent reports have begun to identify methods capable of identifying these structures via susceptibility weighted imaging, or by visualizing white matter boundaries between these structures using optimized MPRAGE acquisitions. We present evidence of the potential for the combined use of these techniques to increase the structures that can identified on an individual level. Furthermore, we demonstrate the utility of imaging with MPRAGE imaging with shorter inerversion delays for intrathalamic parcellation.

15:27 0123.   Region-specific microstructure of cortical areas revealed with high angular resolution diffusion MR microimaging
Manisha Aggarwal1, Olga Pletnikova2, Juan Troncoso2, and Susumu Mori1
1Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States, 2Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, United States

We demonstrate high angular resolution diffusion MR microimaging to resolve the region-specific microstructure of cortical areas in the fixed human brain. Diffusion MRI of cortical tissue microstructure is challenged by both the low anisotropy in gray matter microenvironments and the level of resolution necessary to delineate the layered architecture. Here, using 3D gradient and spin echo based acquisition, HARDI data of cortical specimens were acquired with 30 diffusion directions at 90 µm isotropic resolution. The diffusion micro-imaging data of the prefrontal, primary motor, and primary visual areas revealed the region-specific laminar microstructure of cortical gray matter with unprecedented detail.

15:39 0124.   
Brain volume variations in postmenopausal women: A voxel-based morphometry (VBM) study - permission withheld
Tae-Hoon Kim1 and Gwang-Woo Jeong2
1Research Institute of Medical Imaging, Chonnam National University Medical School, Gwangju, Korea, 2Radiology, Chonnam National University Medical School, Gwangju, Korea

During the past two decades, several studies in females of animal models and human have been performed to unveil the reproductive system changes and the complex interactions with the ovaries. However, morphologic variations in the central nerve system following menopause have not yet been studied. Therefore, this study utilized voxel-based morphormetry (VBM) to evaluate the age-related changes and the effects of menopause on the brain volumes in postmenopausal women.

15:51 0125.   Structural brain changes after rotarod training in mice
Jan Scholz1, Yosuke Niibori2, Paul Frankland2,3, and Jason Lerch1,4
1Mouse Imaging Centre, Hospital for Sick Children, Toronto, ON, Canada, 2Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON, Canada, 3Department of Psychology & Physiology, University of Toronto, Toronto, ON, Canada, 4Medical Biophysics, University of Toronto, Toronto, ON, Canada

Here we investigate how rotarod training affects brain volume and microstrucure using ex-vivo MRI in mice. The rotarod is a standard test that taxes motor coordination and balance. Volume of motor and balance-related regions increases after rotarod training. Volume of the motor cortex is positively correlated with rotarod performace. Diffusion imaging indicates that trained mice have higher FA in the hippocampus. Time spent on the rotarod is associated with higher FA in the hippocampus and lower FA in V1. By using complementary measures of microstructure and volume this study reveals the substantial structural reorganization of the adult mouse brain following a brief period of motor training.

16:03 0126.   Hippocampal surface dentation characteristics through sub-pixel segmentation
Yi Gao1 and Lawrence Ver Hoef1
1University of Alabama at Birmingham, Birmingham, AL, United States

We present a segmentation scheme utilizing sub-voxel precision for the hippocampal dentation structure extraction from 3T MR images. This reveals the degree of dentation varies between normal individuals from prominently dentated to minimally dentated.