Volumetric comparisons of supratentorial white matter hyperintensities on FLAIR MRI in patients with migraine and multiple sclerosis.

Migraine and multiple sclerosis (MS) can both cause white matter lesions that appear similar on conventional MRI. This study aimed to compare these abnormalities, and to find anatomical biomarkers specific for migraine. Supratentorial white matter hyperintensities (WMH) of 17 migraineurs and 15 patients with MS were counted, volumetrically analyzed, and their lobar distribution assessed on fluid-attenuated inversion recovery MRI. We found that migraine WMH affected mainly the deep white matter and subcortical U-fibers, belonged to the anterior circulation, appeared more frequently in the frontal and parietal lobes, showed no difference in average size between lobes, and were smaller and fewer than in MS. Most of the MS WMH were in the frontal lobe and were the smallest average size, while the fewest WMH with the largest size were in the occipital lobe. The pattern of supratentorial WMH appearance differs between the two groups; however, accurate differential diagnosis of WMH by conventional MRI is probably not possible in individual patients.