This study looked at quantitative diffusion tensor and magnetisation transfer imaging measures in the spinal cord to assess lesion burden with high and low disability. 124 people with MS underwent 3-T cervical spinal cord MRI. They calculated the cross-sectional area, fractional anisotropy (FA), mean diffusivity (MD), perpendicular diffusivity, parallel diffusivity and magnetisation transfer ratio (MTR).
Results showed that FA, MD, MTR, perpendicular diffusivity, parallel diffusivity and spinal cord cross-sectional area were more abnormal in the high-vs low-disability subgroup of patients with low lesion count. All MRI measures apart from MTR and parallel diffusivity were more abnormal in the high-vs low-disability subgroup with high lesion counts.
After taking age and sex into consideration, all MRI measures retained differences in the low-lesion subgroup, except parallel diffusivity. While in the high lesion subgroup, only FA, MD and perpendicular diffusivity retained differences.
Therefore, quantitative MRI reflects clinically relevant differences, supporting the use of quantitative MRI in the clinical setting, where accurate measurement of disease burden is becoming very important for assessing treatment efficacy.
Oh J, Saidha S, Chen M
Neurology. 2013 Jan 16. [Epub ahead of print]
Read the abstract