ELECTRONIC POSTER - ismrm

14:30 4320. Profile-Based Cortical Parcellation to Detection of Cortical Multiple Sclerosis
Lesions
Christine Lucas Tardif 1 , John B. Richardson 2 , Claude Lepage 1 , D Louis Collins 1 , Alan C.
Evans 1 , G Bruce Pike 1
1 McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada; 2 Department of
Neuropathology, Montreal Neurological Institute/Hospital, Montreal, QC, Canada
Cortical grey matter (GM) multiple sclerosis lesions are difficult to segment in MR images due to poor contrast with normal appearing
GM and spatial variation in healthy GM. We propose using an observer-independent profile-based method for cortical parcellation to
detect cortical lesions. Following tissue classification and surface extraction, profiles are extended from the white matter surface to the
cortical surface. The cortex is parcellated according to profile intensity and shape using a kmeans classifier with squared Euclidean
distance. The method is tested on high-resolution MR data from a fixed postmortem MS brain, and validated using myelin basic
protein immunohistochemistry.
15:00 4321. Evidence of Distributed Subpial T2* Signal Changes at 7T in Multiple Sclerosis: An
Histogram Based Approach.
Caterina Mainero 1 , Carlos Lima 1 , Julien Cohen-Adad 1 , Doug Greve 1 , Amy Radding 1 ,
Thomas Benner 1 , R Philip Kinkel 2 , Bruce Fischl 1 , Bruce R. Rosen 1
1 A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United
States; 2 Neurology, Beth Israel Deaconess Medical Center, Boston, MA, United States
We investigated whether a histogram-based analysis of 7T T2* signal intensity in the cortex can show distributed subpial cortical
changes in 14 patients with multiple sclerosis (MS), as described histopathologically. We hypothesized that this show significantly
increased T2* signal intensity in patients vs controls. FLASH-T2* spoiled gradient-echo weighted images acquired at 7T. Pial and
white matter surfaces generated by FreeSurfer on a 3T MEMPR were overlaid on the 7T FLASH-T2* images. T2* intensities were
normalized to mean CSF intensity (T2*/CSF ) and then sampled 1mm inside the pial surface. The histogram-based analysis showed
significant, diffuse T2*/CSF signal increases in MS vs matched controls, particularly evident in frontal areas.
Thursday 13:30-15:30 Computer 76
13:30 4322. Optimisation of 3 T and 7 T T 2 * -Weighted MRI for the Detection of Small
Parenchymal Veins in MS Lesions
Jennifer Elizabeth Dixon 1 , Matthew John Brookes 1 , Emma C. Tallantyre 2 , Nikos
Evangelou 2 , Peter G. Morris 1
1 Sir Peter Mansfield Magnetic Resonance Centre, University of Nottingham, Nottingham, Nottinghamshire,
United Kingdom; 2 Department of Clinical Neurology, Nottingham University Hospital NHS Trust, Nottingham,
Nottinghamshire, United Kingdom
Post-mortem studies of MS lesions show a close spatial relationship to parenchymal veins. In vivo study of this has previously been
limited by the difficulties in demonstrating both lesions and veins on a single MR image. Recently, we have shown that T2*-weighted
MRI at 7T enables simultaneous visualisation of both structures, and found that 82% of white-matter MS lesions contained a
detectable vein. Here, we predict optimal scanning parameters for increasing the sensitivity of vessel detection and reducing the
inherent bias towards detection of veins with particular orientations.
14:00 4323. High Resolution Magnetic Susceptibility Mapping in Patients with Clinically
Isolated Syndrome
Ali Al-Radaideh 1 , Samuel Wharton 1 , Su-Yin Lim 2 , Christopher Tench 2 , Cris
Constantinescu 2 , Richard Bowtell 1 , Penny Gowland 1
1 Sir Peter Mansfield MR Centre, The University of Nottingham, Nottingham, Nottinghamshire, United
Kingdom; 2 Clinical Neurology, The University of Nottingham, Nottingham, Nottinghamshire, United Kingdom
Neurodegeneration in MS might be expected to cause an accumulation of iron in deep grey matter (dGM) structures. The aim of this
study is to measure the susceptibility of dGm structures in patients with Clinically Isolated Syndrome (CIS), an early manifestation of
MS.
14:30 4324. Iron-Sensitive Quantitative Methods for Multiple Sclerosis: Lesion Evolution and
Deep Grey Matter Iron Deposition
Robert Marc Lebel 1 , Amir Eissa 1 , Peter Seres 1 , Derek J. Emery 2 , Gregg Blevins 3 , Alan H.
Wilman 1
1 Biomedical Engineering, University of Alberta, Edmonton, Alberta, Canada; 2 Radiology and Diagnostic
Imaging, University of Alberta, Edmonton, Alberta, Canada; 3 Neurology, University of Alberta, Edmonton,
Alberta, Canada
Three iron-sensitive methods are applied at 4.7T for tracking iron-based changes in the brain of patients with relapsing-remitting
multiple sclerosis (MS). The methods are phase susceptibility, R2 and R2* mapping. Each method is applied with special high field
adaptations. They are used to track lesion progression as well as deep grey matter changes. Each measure provides unique contrast
and its own sensitivity and specificity to iron. Together these methods can provide new insight into MS progression.