| Brain lesions |
| High signal on T2-weighted and FLAIR MRI sequences (more than nine lesions) |
| When actively inflamed, often enhanced with gadolinium contrast |
| Position abutting ventricles (often perpendicular) |
| Juxtacortical position (gray-white junction) |
| Involvement of brainstem, cerebellum, or corpus callosum |
| Spinal cord lesions |
| One or two vertebral segments in length |
| Incomplete cross-sectional involvement (dorsolateral common) |
| Less likely to enhance with gadolinium contrast |
| No cord swelling |
| Better seen with STIR MRI sequences |