The transient global amnesia-migraine connection.

Twelve patients with transient global amnesia (TGA) were studied. Seven (58%) of the 12 had a headache during their attack; five (42%) of the 12 were migraineurs. Measurement of regional cerebral blood flow (rCBF) by the xenon Xe 133 inhalation method showed similar patterns of flow in five of the seven patients tested. The rCBF abnormalities were impaired vasomotor response in the watershed area between the middle cerebral artery and posterior cerebral artery territories, and/or focal ischemia in the inferior part of the temporal lobe. These rCBF abnormalities differed from those seen in patients with carotid transient ischemic attacks (TIAs) and vertebrobasilar TIAs. We speculate that the vasomotor phenomena in migraine may play a major role in the cause of TGA.