[Unruptured intracranial aneurysms associated with vascular disorder of the vertebro-basilar system: report of five cases].

: Among fifty-two angiographically examined patients of vertebro-basilar disorder, incidental intracranial aneurysms were found in five cases. These were four males and a female, ages ranging from 42-67 year old. Vertebro-basilar disorders were ischemic origin in three cases and hemorrhage in two cases. Locations of incidental aneurysms were the internal carotid artery, middle cerebral artery, anterior communicating artery and basilar artery. They were multiple in three cases. They were operated on radically, except one case whose status seemed to be untolerable to the operation. Intervals between strokes and operations were 51-81 days. In spite of successful operation, mild to moderate disturbances of consciousness appeared in three cases. In two cases they were subsided in a week, but in one case it persisted for two months. Fortunately, final results in all operative cases were good. These transient deterioration of consciousness level might probably be ascribed to vertebro-basilar insufficiency once subsided but resumed due to the operative affections. Through a small experience of four cases, three points would be discussed to prevent such hazards. 1) Extreme systemic hypotension as well as hypertension should be avoided during operation. 2) GOF might be an anesthesia of choice in such cases. 3) Operation should be favorably waited for more than six months after the ictus.