Migraine: evaluation by MR

Twenty-four patients clinically diagnosed as having migraine (17 of the classic or common type and seven of the complicated type) were evaluated on a 0.5-T or 0.6-T superconductive MR imaging unit with the objective of detecting associated parenchymal lesions. Thirteen (54%) of the patients had normal MR studies. Eleven (46%) of the patients (seven with classic or common and four with complicated migraine) showed well-defined lesions with prolonged T2 signal intensity. The lesions associated with classic migraine were focal and predominantly distributed in the periventricular white matter, bilateral in four and unilateral in three. In the group with complicated migraine, larger cortical abnormalities similar to infarcts were seen in three patients and multiple bilateral focal white matter lesions were seen in one. Almost all the lesions were evident only on T2-weighted studies; a few exhibited hypointense signal intensity on T1-weighted studies. The focal periventricular white matter lesions were not necessarily associated with neurologic deficits, but the cortical lesions were. Our study indicates that parenchymal changes are frequently associated with migraine and that MR may well be the screening and diagnostic method of choice for their detection and evaluation.