Multiple Sclerosis - Clinical Applications
Tuesday 21 April 2009
Room 310 16:00-18:00


Nicola de Stefano and Massimo Filippi

16:00  337. High Resolution Magnetization Transfer Imaging at 7T
    Olivier E. Mougin1, Ali al-Radaideh1, Ron Coxon1, Emma C. Tallantyre2, Matthew J. Brookes1, Nikos Evangelou3, Penny A. Gowland1
Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, Nottinghamshire, UK; 2Departement of Clinical Neurology, Medical School, University of Nottingham, Nottingham, Nottinghamshire, UK; 3School of Medical & Surgical Sciences, University of Nottingham, Nottingham, Nottinghamshire, UK
    High resolution (1x1x1mm3) MTR scans have been acquired at 7T using a novel imaging sequence. The MTR contrast has been compared between 7 and 3T, showing a greater grey matter (GM) / white matter (WM) contrast to noise ratio at 7T, providing a good delineation of WM lesions at high resolution with the MTR contrast. The sequence is being used to study white matter changes in MS patients.
16:12 338. Regions of Reduced Cortical Magnetization Transfer Ratio Detected in MS Patients Using Surface-Based Techniques
    Mishkin Derakhshan1, Zografos Caramanos1, Sridar Narayanan1, Donald Louis Collins1, Douglas Lorne Arnold1
Montreal Neurological Institue, McGill University, Montreal, QC, Canada
    The multiple sclerosis imaging community still struggles with the in vivo detection of cortical grey matter lesions. In this abstract we quantified the extent of subpial decreases of magnetization transfer ratio of the cortical grey matter, which may indicate regions of cortical demyelination, in groups of MS patients and healthy controls. To increase our sensitivity, we exploited the knowledge gained from pathological studies of the unique geometry of these lesions, and carried out our analyses on two-dimensional parametric surface models of the cortex, instead of the three-dimensional voxel-wise analyses traditionally used.
16:24 339. Optimisation of 7T Double-Inversion Recovery (DIR) Imaging to Improve Detection of MS Lesions In Vivo
    Jennifer Elizabeth Dixon1, Paul S. Morgan2,3, Matthew J. Brookes1, Ali M. Al-Radaideh1, Emma C. Tallantyre4, Nikos Evangelou4, Peter G. Morris1
Sir Peter Mansfield Magnetic Resonance Centre, University of Nottingham, Nottingham, Nottinghamshire, UK; 2Radiology & Radiological Science, Medical University of South Carolina, Charleston, SC, USA; 3Academic Radiology, University of Nottingham, Nottingham, Nottinghamshire, UK; 4Department of Clinical Neurology, University of Nottingham, Nottingham, Nottinghamshire, UK
    DIR sequences have proved useful in the detection of cortical MS lesions. However, the inherently low SNR of this sequence suggests the importance of developing it at higher field. This requires the determination of inversion times to provide the desired contrast between grey matter, white matter and CSF, and must address the effects of variation in flip angle due to B1 inhomogeneity at 7T, as well as reduce the TR to obtain clinically acceptable scan times. We use this theory to produce high-resolution images acquired at 7T, which show clearly areas of signal hyperintensity associated with MS lesions.
16:36 340. Detection of Cortical Lesions in Multiple Sclerosis Using FLAIR, DIR and Ultra High Field MPRAGE
    Emma Clare Tallantyre1, Jennifer E. Dixon2, Matthew J. Brookes2, Ali Al-Radaideh2, Paul S. Morgan3,4, Nikos Evangelou1, Peter G. Morris2
Clinical Neurology, Nottingham University, Nottingham, UK; 2Sir Peter Mansfield MR Centre, Nottingham University, Nottingham, UK; 3Radiology & Radiological Sciences, Medical University of South Carolina, Charleston, USA; 4Academic Radiology, Nottingham University, Nottingham, UK
    Objective: To investigate whether cortical MS lesions detected using 3T DIR are also seen using ultra high field (7T) MRI. Methods: MR imaging at 3T and 7T of 11 MS patients and 8 controls.  Results: DIR was susceptible to artefact in controls. A proportion of cortical lesions identified on 3T DIR appear to be genuine. However, enhanced spatial resolution of 7T MPRAGE better determines the anatomical location of lesions and some cortical hyperintensities on 3T DIR seem to arise from extracortical blood vessels. Conclusions: Ultra high field MRI increases sensitivity and specificity in the detection of cortical lesions.
16:48 341. Evaluation of Cortical Lesions Conspicuity in Multiple Sclerosis: 7T Vs 3T MRI
    Caterina Mainero1, Thomas Benner1, Amy Radding1, Rikke Jensen2, Andre van der Kouwe1, R P. Kinkel2, Bruce R. Rosen1
A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; 2Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA
    In this study we assessed the use of 7T MRI to (1) visualize cortical lesions, including all histopathological types, in patient with multiple sclerosis (MS); (2) characterize the contrast properties of cortical lesions including T2*, T2, T1, and phase images to assess which MR contrasts are more sensitive to cortical pathology; (3) compare the ability of the 7T images that showed higher contrast for cortical plaques with that from 3T in disclosing cortical MS pathology. 7T MRI, and particularly FLASH-T2* scans, showed greater potential than 3T MRI not only in detecting cortical lesions but also in characterizing them as described histopathologically.
17:00 342. High Resolution In-Vivo and Post-Mortem R2* and Phase Images of Multiple Sclerosis Lesions at 7 T
    Bing Yao1, Francesca Bagnato1, Hellmut Merkle1, Peter van Gelderen1, Fredric K. Cantor1, Joan Ohayon1, Henry McFarland1, Jeff H. Duyn1
NINDS, National Institutes of Health, Bethesda, MD , USA
    R2* and phase images have been exploited to investigate brain tissue microstructure. In this study, MS patients and brain specimens of an MS deceased patient were imaged using a 7 T MR scanner and the R2* and phase images were investigated. Heterogeneity appearances of the MS lesions are found in the high resolution R2* and phase images, for both in-vivo and extra-vivo tissues. We here aim at providing new insights on the major sources that contribute to the MRI contrast in MS lesions.
17:12 343. Demyelination and Remyelination in New Multiple Sclerosis Lesions: Insights from Serial Myelin Water Imaging
    Cornelia Laule1, Irene M. Vavasour1, Shannon H. Kolind2, Burkhard Maedler3, Anthony L. Traboulsee4, Penny Smyth4, Alex Rauscher1, John Hooge4, Virginia Devonshire4, Joel Oger4, Wayne Moore5, David KB Li1,4, Alex L. MacKay1,2
Radiology, UBC, Vancouver, BC, Canada; 2Physics & Astronomy, UBC, Vancouver, BC, Canada; 3Philips Healthcare, Vancouver, BC, Canada; 4Neurology, UBC, Vancouver, BC, Canada; 5Pathology & Laboratory Medicine, UBC, Vancouver, BC, Canada
    Histological studies show cycles of demyelination and remyelination occur in multiple sclerosis (MS) lesions. MR measures of myelin water fraction (MWF), water content (WC) and geometric mean T2 (GMT2) measured by multi-echo T2 relaxation provide insight into the myelination state of MS lesions.We utilized a 3D T2 relaxation sequence to follow MWF, WC, GMT2 and also measured T1 on a monthly basis to elucidate the time course of pathological changes in new MS lesions. The behaviour of new lesions varied between subjects, with some lesions showing recovery. WC and MWF can monitor the evolution of demyelination and remyelination in MS.
17:24 344. Whole-Brain Voxel-Wise Analysis of Myelin Water Volume Fraction in Multiple Sclerosis
    Sean CL Deoni1
Centre for Neuroimaging Sciences, London, UK
    The ability to distinguish affected, but normal appearing, white matter tissue has significant clinical application to MS and other de-myelinating disorders. Currently, this may be accomplished using histogram analysis, but at the expense of spatial information. Here we demonstrate a patient-specific approach, involving the comparison of voxel-wise myelin volume fraction values, obtained using the mcDESPOT multi-component relaxometry technique, to a reference population-matched atlas. We demonstrate the ability to visualize areas of significantly reduced myelin fraction within tissue that appears normal on conventional T1 or T2 weighted scans.
17:36 345. Differentiation of Pathological Processes and Clinical Forms in Multiple Sclerosis: A Tract Based Spatial Statistics Study
    Salem Hannoun1,2, Francoise Durand-Dubief1,3, Danielle Ibarrola2, Jean Christophe Comte2, Christian Confavreux3, Dominique Sappey-Marinier1,2
CREATIS-LRMN, UMR5220 CNRS & U630 INSERM & Université de Lyon, Bron, France; 2CERMEP-Imagerie du vivant, Bron, France; 3Hopital Neurologique, Groupement Hospitalier Est, Bron, France
    This study aims to characterize the pathological processes and differentiate the clinical forms of multiple sclerosis (MS) patients using tract based spatial statistics (TBSS). Significant decreases of FA values were observed in numerous white matter regions of MS patients (SP, PP and RR forms) when compared to control subjects. These decreases were also more pronounced when comparing patients with more advanced forms (SP and PP) to RR patients while no significant differences were observed between SP and PP groups. This technique constitutes an important new tool to follow the disease progression and better characterize the alterations extent between patients clinical status.
17:48 346. Application of Lesion Probability Maps to Predict Progression in Primary-Progressive Multiple Sclerosis: A 10-Year Multi-Centre Study
    Benedetta Bodini1, Marco Battaglini2, Nicola De Stefano2, Zhaleh Khaleeli1, Frederik Barkhof3, Bruno Brochet4, Vincent Dousset5, Massimo Filippi6, Xavier Montalban7, Chris Polman3, Marco Rovaris6, Alex Rovira7, Jaume Sastre-Garriga7, David H. Miller8, Rebecca Samson8, Olga Ciccarelli1, Alan J. Thompson1
Dept. of Brain Repair and Rehabilitation, Institute of Neurology, UCL, London, UK; 2Dept. of Neurological and Behavioural Sciences, University of Siena, Siena, Italy; 3Department of Radiology, MS Center, VU University Medical Centre, Amsterdam, Netherlands; 4Hopital Pellegrin, Centre Hospitalier Universitaire, Bordeaux, France; 5Bordeaux Neuroscience Institute, University Victor Segalen, Bordeaux, France; 6Neuroimaging Research Unit, San Raffaele Scientific Institute, Milan, Italy; 7Depts. of Neuroimmunology and Radiology, Hospital Vall d’Hebron, Barcelona, Spain; 8Dept. of Neuroinflammation, Institute of Neurology, UCL, London, London, UK
    The aim of this study was to assess whether the spatial distribution of T2 lesions predicted long-term progression in primary progressive multiple sclerosis (PPMS). To clarify this issue, we applied Lesion Probability Map, a novel technique, to a large cohort of PPMS patients followed-up over 10 years. We found that the spatial distribution of T2 lesions at baseline was relevant in predicting the risk of long-term progression. In particular, lesions in the motor and associative tracts correlated with more rapid clinical progression. We confirmed that male gender was associated with a worse long-term prognosis.