Elderly Patients with Ongoing Migraine Show Reduced Gray Matter Volume in Second Somatosensory Cortex

To identify structural changes in gray matter in suspected migraine generators (the hypothalamus and/or brainstem nuclei) and pain pathways and to evaluate whether structural changes in migraine are definitive or resolve with age.

Voxel-based morphometry (VBM) was used to assess differences in gray matter between 39 healthy controls (HC), 25 episodic migraine (EM) subjects, and 37 subjects with a history of migraine (HM). In addition, morphometric changes were specifically investigated in suspected migraine generators and/or pain pathways. For statistical analyses, t tests between the groups were performed, and a correction for multiple comparisons was used.

Whole-brain analysis did not reveal any gray or white matter changes. However, when the analysis was limited to the pain matrix, a lower gray matter volume was observed in the left second somatosensory (SII) cortex in EM subjects compared to HC subjects. This volume was significantly reduced in the EM group compared to the HC group and to the HM group, but not in the HM group compared to the HC group.

Morphometric abnormalities in the SII in subjects with ongoing migraine but not in subjects with a resolved migrainous disease are likely to characterize a migrainous state rather than be a marker of brain susceptibility to migraine.