Longitudinal Changes in Quantitative Spinal Cord MRI in Multiple Sclerosis Patients: Results of a 5-year Study (S47.001)

Objective: To assess quantitative spinal cord(SC)-MRI measures over 5 years, and characterize the relationship between changes in quantitative SC-MRI with clinical disability. Background: Prior studies have shown that quantitative SC-MRI measures correlate with MS-related clinical disability, but the evaluation of longitudinal changes in quantitative SC-MRI in MS has been limited. Design/Methods: 75 MS patients underwent 3T SC-MRI and clinical assessment (expanded disability status scale[EDSS]) at baseline, 2, and 5 years. Regions-of-interest circumscribing axial SC cross-sectional area(CSA) at C3–C4 were used to obtain: CSA, fractional anisotropy(FA), mean, perpendicular, parallel diffusivity(MD, λ⊥, λ||,) and magnetization-transfer-ratio(MTR). Mixed-effects regression incorporating subject-specific intercepts and slopes was utilized to assess longitudinal change in SC-MRI measures. Pearson’s coefficient(r) assessed relationships between subject-specific slopes and follow-up EDSS scores. Results: SC-CSA and MTR decreased, while MD increased (p=0.009, p=0.03, p=0.09) over the follow-up period of 5.7 years. There were moderately strong correlations between subject-specific slopes of individual SC-MRI indices and follow-up EDSS scores at both 2 and 5 years[2 years: r with FA=−0.23(p Conclusions: In MS, changes in quantitative SC-MRI indices are measurable over 5 years, likely reflecting ongoing pathological processes. Of clinical relevance is that subject-specific trajectories of SC-MRI index changes at both 2 and 5 years are highly relevant to disability at follow-up, and subject-specific trajectories at 2 and 5 years are strongly correlated. These findings suggest that individual dynamics of change should be compared to average values when interpreting longitudinal SC-MRI measures, and that measuring short-term change is predictive of long-term clinical disability, which could expand the clinical utility of these techniques. Study Supported by: National MS Society, MS Society of Canada Disclosure: Dr. Oh has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with EMD-Serono, Novartis, Biogen-Idec, Sanofi-Genzyme, Roche, Teva. Dr. Oh has received research support from Biogen-Idec. Dr. Cybulsky has nothing to disclose. Dr. Chen has nothing to disclose. Dr. Suthiphosuwan has nothing to disclose. Dr. Seyman has nothing to disclose. Dr. Carass has nothing to disclose. Dr. Diener-West has nothing to disclose. Dr. Van Zijl has nothing to disclose. Dr. Prince has nothing to disclose. Dr. Reich has nothing to disclose. Dr. Calabresi has nothing to disclose.