Perfusion weighted imaging during migraine: spontaneous visual aura and headache

Using perfusion weighted imaging, we studied 28 spontaneous migraine episod es; 7 during visual aura (n=6), 7 during the headache phase following visua l aura (n=3), and 14 cases of migraine without aura (n = 13). The data were analyzed using a region-of-interest-based approach. During aura, relative cerebral blood flow (rCBF) was significantly decreased (27%+/-0.07) in occi pital cortex contralateral to the affected hemifield. rCBV was decreased (1 5%+/-0.12) and mean transit time increased (32%+/-0.3), persisting up to 2. 5 h into the headache phase. Other brain regions did not show significant p erfusion changes. During migraine without aura, no significant hemodynamic changes were observed. In one patient who experienced both migraine with an d without aura, perfusion deficits were observed only during migraine with aura. These findings suggest that decremental blood flow changes in occipit al lobe are most characteristic of migraine with aura.