TRADITIONAL POSTER - ismrm

Poster Sessions
veins and iron-rich regions in human brain. In this study, we show that the susceptibility-induced contrast in gradient-echo phase images can improve
detection of amyloid plaques.
2323. Automatic Detection of Amyloid Plaques on Ex Vivo APP/PS1 Mouse Brain Using a Zoom T2-
Weighted Spin Echo Sequence
Benjamin Marty 1 , Céline Giraudeau 1 , Julien Flament 1 , Sidi Mohamed Ahmed Ghaly 1 , Franck
Lethimonnier 1 , Fawzi Boumezbeur 1 , Julien Valette 1 , Sébastien Mériaux 1
1 CEA/DSV/I2BM/Neurospin, Gif-Sur-Yvette, France
Amyloid plaques are a marker of Alzheimer's disease which are traditionally detected as hypointense signals on T2*-weighted images due to the presence of
iron. This study proposes a comparison between the images of an ex vivo APP/PS1 mouse brain obtained using a conventional T2* gradient echo sequence
and a zoom adiabatic T2 spin echo sequence. This comparison, based on the ability of both sequences to allow successful plaques detection using an
automatic home-made procedure, reveals that T2 contrast allows resolving amyloid plaques with a better specificity than T2* contrast, which is disturbed by
the hypointense signals coming from blood vessels.
2324. Anatomical Phenotyping of Rett Syndrome in the Mouse
Jacob Ellegood 1 , Jason P. Lerch 1 , R Mark Henkelman 1
1 Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada
Rett Syndrome is an X-linked disorder, which primarily affects females, and is caused by mutations to the Mecp2 gene. A commonly used mouse model of
RTT involves a truncation of the Mecp2 gene at codon 308. The purpose of this study was to examine the volume changes in the Mecp2 308 Rett syndrome
mouse model with high resolution MRI. Volume changes were found in many regions, for example, significant decreases were found in the cerebral cortex
as well as increases in the cerebellar cortex and ventricles.
2325. A Transversal and Longitudinal MRI Study in Patients with Cervical Dystonia Using VBM Analysis.
Porzia Totaro 1 , Eytan Raz, Gian Marco Contessa, Francesca Tona, Giovanni Fabbrini, Alfredo Berardelli,
Carlo Colosimo, Luigi Bozzao, patrizia pantano 2
1 Department of Neurological Sciences, Sapienza University of Rome, Rome, Italy; 2 Sapienza University of Rome, Rome, Italy, Italy
A transversal and longitudinal MRI study in patients with cervical dystonia using voxel-wise comparison of the local Gray Matter concentration.
2326. MRI of the Lumbar Spine at 7 Tesla in Healthy Volunteers and a Patient with Spina Bifida
Astrid Ellen Grams 1,2 , Oliver Kraff, 12 , Lale Umutlu 1,2 , Stefan Maderwald, 12 , Philipp Dammann, 2,3 , Mark E.
Ladd, 12 , Michael Forsting 1,2 , Elke Ruth Gizewski 1,2
1 Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, NRW, Germany;
2 Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Hospital Essen, Essen, NRW, Germany; 3 Department of
Neurosurgery, University Hospital Essen, Essen, NRW, Germany
In the present study the feasibility of imaging of the lumbar spine and its adjacent structures under healthy and under pathological conditions at 7 Tesla was
investigated. A combination of a 3D-CISS and a 3D-VIBE sequence comprehended imaging of the vertebrae, the intervertebral discs, the bony neural
foramina, the facet joints, the dural sac and the intraspinal portions of the spinal nerves.
2327. Voxel-Based Morphometric Analysis of Gray and White Matter in Perinatally HIV-Infected Youth
Manoj Kumar Sarma 1 , Rajakumar Nagarajan 1 , Michael Albert Thomas 1 , Judy Hayes 2 , Jaime Deville 3 ,
Karin Nielsen 3 , David Michalik 4 , Whitney B. Pope 1 , Margaret A. Keller 2
1 Radiological Sciences, UCLA, Los Angeles, CA, United States; 2 Pediatrics, Harbor-UCLA Medical Center, Torrance, CA, United
States; 3 Pediatrics, UCLA, Los Angeles, CA, United States; 4 Miller’s Children’s Hospital, Long Beach, CA, United States
Voxel-based morphometry was used to compare both gray and white matter volume in perinatally human immunodeficiency virus (HIV)-infected youth
versus healthy controls. HIV patients had reduced gray matter volume in the bilateral caudate nucleus, left parietal lobe, but an increase of gray matter
volume in the frontal lobe, posterior temporal lobe, and parietal lobe. Striking white matter volume reductions were found in the temporal lobe, pons, right
pre-frontal area, corpus callosum and the junction of the thalamus and mid brain. These findings suggest the sensitivity of VBM in evaluating GM and WM
abnormalities in perinatally HIV-infected youth.
2328. The Effects of Voxel Size and Image Smoothing on R2* Measurements of the Human Brain
Christian Denk 1 , Alexander Rauscher 1
1 UBC MRI Research Centre, University of British Columbia, Vancouver, BC, Canada
Quantitative imaging of the R2* relaxation rate employing multiple echoes can be used to assess blood oxygenation and iron content in neural structures.
However, R2* is not a strictly intrinsic tissue property, as it also depends on the spatial relationship between voxel geometry and background field
inhomogeneities. These background field inhomogeneities cause additional signal decay. To investigate the influence of spatial resolution and smoothing on
R2* values, we acquired images with high spatial resolution and applied spatial smoothing to the complex data, which simulates acquisition at lower spatial
resolution, and to the magnitude data. We found that both changes in spatial resolution and spatial smoothing of magnitude of high resolution data leads to
strong changes in R2*, which suggests that R2* values should be interpreted in the light of data acquisition parameters as well as data smoothing.