Amnesia following the rupture and repair of an anterior communicating artery aneurysm.

Clinical analysis and neuropsychological criteria derived from experimental studies of human amnesic syndromes, particularly the alcoholic Korsakoff's syndrome, have been used to characterise an unusual form of amnesia that occurred in two patients after rupture of an anterior communication cerebral artery aneurysm. Intraoperative observation and multiple CT scans did not reveal focal brain damage. Arteriography showed that both patients had arterial vasospasm. The amnesia has persisted over three years since the surgery. Study of the characteristics of their amnesia showed several features in common with other amnesic syndromes, including severely depressed free recall, and less depressed recognition of visual and verbal material. Chronic amnesic syndromes with characteristics of classical amnesic syndromes occur infrequently after rupture and repair of intracranial aneurysms, and, if not caused by parenchymal haemorrhage, may follow pre-operative vasospasm.