Julien Cohen-Adad^1,2, Mohamed-Mounir El Mendili³, Stéphane Lehéricy⁴, Pierre-François Pradat⁵, Sophie Blancho⁶, Serge Rossignol⁷, and Habib Benali^3
1A.A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, United States, ²Harvard Medical School, Boston, MA, United States, ³UMR-678, INSERM-UPMC, Pitié-Salpêtrière Hospital, Paris, France, ⁴CENIR, CRICM, UPMC, UMR-S975, INSERM U975, CNRS UMR 7225, Groupe Hospitalier Pitie-Salpetriere, Paris, France, ⁵Fédération des Maladies du Système Nerveux, AP-HP, Pitié-Salpêtrière Hospital, Paris, France, ⁶Institut pour la Recherche sur la Moelle Epinière et l'Encéphale, France, ⁷GRSNC, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada

We combined diffusion-weighted imaging (DWI), Magnetization Transfer (MT) and atrophy measurements to evaluate the cervical spinal cord of patients with chronic spinal cord injury (SCI). We used high in-plane resolution to delineate dorsal and ventrolateral pathways. Significant differences were detected between patients and controls in the normal-appearing white matter and all metrics were remarkably well correlated with clinical disability. The specificity of axial and radial diffusivity and MT measurements suggests the detection of degeneration and demyelination in SCI patients. Combining DWI with MT imaging is a promising approach to gain specificity in characterizing spinal cord pathways in traumatic injury.

Laura Elizabeth Gonzalez-Lara^1,2, Xiaoyun Xu³, Arthur Brown^3,4, and Paula J Foster^1,2
1Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada, ²Department of Medical Biophysics, The University of Western Ontario, London, ON, Canada, ³Robarts Research Institute, London, ON, Canada, ⁴Department of Anatomy and Cell Biology, The University of Western Ontario, London, ON, Canada

Among the treatments being studied for spinal cord injury (SCI) an area of great interest is stem cell therapy. In animal models of SCI stem cells are commonly transplanted directly into the injured cord. We show that the noninvasive and 3D nature of MRI is crucial for gaining an appreciation of the location of transplanted stem cells and their fate over time. We show how MRI allows us to verify precise delivery of the cells to the intended target in vivo and to observe the overall distribution beyond the tissue or organ of interest at different time points.

Nadia Barakat¹, Louis Hunter², Jürgen Finsterbusch³, John Gaughan¹, Amer Samdani², MJ Mulcahey², Randal Betz², Scott Faro¹, and Feroze Mohamed^1
1Temple University, Philadelphia, PA, United States, ²Shriners Hospital For Children, ³University Medical Center Hamburg-Eppendorf, Hamburg, Germany

Diffusion Tensor Imaging (DTI) of the pediatric Spinal Cord (SC) poses several challenges. The small cord size has inherent low Signal-to-Noise Ratio (SNR) of the diffusion signal which is vital in MR imaging, respiration/cardiac movements cause artifacts, and echo planar imaging sequences used for obtaining diffusion indices cause eddy current distortions (1). The choice of the MRI pulse sequence and its proper optimization are crucial to successfully overcome these challenges. The purpose of this study was to (a) evaluate the validity and reliability of DTI in children using a newly developed inner-Field-of-View (iFoV) sequence with spatially selective 2D RF excitations (2), (b) examine reproducibility of the DTI measures and (c) investigate DTI parameters in children with and without Spinal Cord Injury (SCI).

Mohamed Tachrount¹, Guillaume Duhamel¹, André Maues de Paula², Jérôme Laurin³, Tanguy Marqueste³, Patrick Decherchi³, Patrick J Cozzone¹, and Virginie Callot^1
1Centre de Résonance Magnétique Biologique et Médicale (CRMBM, UMR 6612, CNRS), Faculté de Médecine, Université de la Méditerranée, Marseille, France, ²Service d’Anatomie Pathologique, Hôpital de la Timone, Marseille, France, ³Institut des Sciences du Mouvement (ISM, UMR CNRS 6233), Faculté des sciences, Université de la Méditerranée, Marseille, France

In this preliminary study, we used high-spatially resolved 1H-MRS, in combination with refine adjustments and dedicated quantification, to examine medullar and thalamic metabolic alterations following spinal cord injury in mice, from the very first days to six weeks after injury. Multi-slice DTI were concomitantly acquired at each time-point and immuno-histochemistry was performed to investigate correlation with both MRS and DTI data.

Yunyan Zhang¹, V. Wee Yong¹, R. John Hurlbert¹, and Steve Casha^2
1University of Calgary, Calgary, AB, Canada, ²Dalhousie University, Halifax, Nova Scotia, Canada

Acute spinal cord injury (SCI) in 50 patients treated with either minocycline (24) or placebo (26) was followed using quantitative MRI. Maximum canal compromise (MCC), maximum spinal cord compression (MSCC), the length and area of T2 hyperintensity on MR images were evaluated at day1, day7, week4, and week52 of injury. While not significantly different (p>0.05) the minocycline group tended to have less MSCC than the placebo group. Similar trend was identified in T2 lesion length and area but at a lesser extent. It suggests that minocycline may be beneficial in acute SCI which however is subject to further confirmation.

Maria Assunta Rocca^1,2, Mark A Horsfield³, Stefania Sala¹, Paola Valsasina¹, J Drulovic⁴, Maria Emma Rodegher², Domenico Caputo⁵, Massimiliano Copetti⁶, T Stosic-Opincal⁷, Sarlota Mesaros⁴, Giancarlo Comi², and Massimo Filippi^1,2
1Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, Scientific Institute and University Hospital San Raffaele, Milan, Italy,²Department of Neurology, Scientific Institute and University Hospital San Raffaele, Milan, Italy, ³Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom, ⁴Institute of Neurology, Clinical Centre of Serbia, Faculty of Medicine, University of Belgrade, Belgrade, ⁵Department of Neurology, Scientific Institute Fondazione Don Gnocchi, Milan, Italy, ⁶Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy, ⁷Institute of Radiology, Clinical Centre of Serbia, Faculty of Medicine, University of Belgrade, Belgrade

In this multi-center study, we applied a new semi-automatic method which allows segmenting the entire cervical cord, to investigate the correlation between cervical cord atrophy and clinical disability in 333 patients with multiple sclerosis (MS), spanning the major clinical phenotypes, with a wide range of clinical disability. Cervical cord area was significantly different among the different MS clinical phenotypes, and it was significantly associated with clinical disability, with a differential effect among disease clinical phenotypes. The stability of cervical cord area measurement among different centers supports its use as surrogate marker to monitor disease progression in multicenter trials.

Benjamin M Ellingson¹, John Grinstead², Josef Pfeuffer³, Thorsten Feiweier³, Langston Holly⁴, and Noriko Salamon^1
1Radiological Sciences, University of California Los Angeles, Los Angeles, CA, United States, ²Siemens Healthcare, Portland, OR, United States, ³Siemens Healthcare, Erlangen, Germany, ⁴Neurosurgery, University of California Los Angeles, Los Angeles, CA, United States

Cervical spondylotic myelopathy (CSM) is a common spinal disorder characterized by degeneration of verebral bodies, intervertebral disks, facet joints, and the associated ligaments typically resulting in formation of bony spurs and myelopathy. An imaging biomarker sensitive to the degree of neurological impairment and recovery after surgery is desired. In the current study, we utilize a custom 2D spatially selective RF excitation pulse combined with a reduced field-of-view single-shot echoplanar readout (Zoomed-EPI) to obtain high resolution, high-quality diffusion tensor images of the neurologically-intact spinal cord and the spinal cord of patients with CSM.

Henry Szu-Meng Chen¹, Nathan Holmes², Jie Liu², Wolfram Tetzlaff², and Piotr Kozlowski^1,2
1UBC MRI Research Centre, Vancouver, BC, Canada, ²ICORD, Vancouver, BC, Canada

Myelin water fraction (MWF) map and T2 relaxation time of myelin water were obtained from excised rat spinal cord at 3 and 8 weeks post injury. Electron microscopy (EM) was used to quantify myelin water content. MWF and T2 of myelin water at the injured fasciculus gracilis both decreased at 8 weeks. EM result indicated 2 to 3 time more myelin water in myelin debris than in intact myelin, which suggests that MWF is not an accurate measure of content of intact myelin when myelin debris is present due to the increased MWF in myelin debris.

Andreas Hock¹, Erin Leigh MacMillan², Alexander Fuchs¹, Roland Kreis², Peter Boesiger¹, Spyros Kollias³, and Anke Henning^1
1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland, ²Dept. of Clinical Research, University of Bern, Bern, Switzerland, ³University Hospital of Zurich, Institute of Neuroradiology, Zurich, Switzerland

1H non-water-suppressed MR spectroscopy with the metabolite cycling technique is introduced for measurements in the spinal cord. The high SNR of the water peak allows frequency alignment of FIDs before signal averaging to improve the spectral quality (line shape and SNR) of the metabolite peaks. A study on 3 volunteers demonstrates the feasibility of the method and results in a higher SNR for metabolite cycled spectra as compared with VAPOR water suppressed acquisitions: (mean ± SD) 6.3 ± 0.6, and 4.7 ± 0.6, respectively.

Adrienne N. Dula^1,2, Richard D. Dortch^1,2, Bennett A. Landman^1,3, John C. Gore^1,2, and Seth A. Smith^1,2
1Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States, ²Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States, ³Electrical Engineering and Computer Science, Vanderbilt University, Nashville, TN, United States

Chemical exchange saturation transfer (CEST) at 3T has been used to calculate the amide proton transfer asymmetry (APTasym) to detect subtle characteristics of multiple sclerosis (MS) lesions in the spinal cord. A white matter lesion in the dorsal column demonstrated T2 hyperintensity and a relative decrease in MTR. APTasym measures from the five healthy controls found a significant difference between gray matter and white matter. This difference can be attributed to differences in the exchange properties and concentrations of amide protons in healthy gray/white matter in the spinal cord.