Abstract
Forty-two cases with a total of 50 untreated unruptured cerebral aneurysms, who were experienced during 6 years from April 1979 to March 1985, were studied in this report. There were 15 males and 27 females and their age range was 38 to 75 years with a mean age of 60.4 years. 16 aneurysms located on the internal carotid artery, 14 on the anterior cerebral artery, 9 on the middle cerebral artery, 3 on the posterior cerebral artery, and 8 on the vertebrobasilar artery. 42 aneurysms were less than 10 mm in diameter, 4 from 10 to 20 mm, and 4 larger than 20 mm. Hypertension was associated in 12 cases, cerebral infarction in 7, head injury in 4, moyamoya disease in 2, and so on. Reasons for not operating were as follows : severe disability due to initial subarachnoid hemorrhage or underlying diseases in 13, advanced age in 8, unwillingness in 13, not notify to patient or family in 4, and technical problems for operation in 3. 4 aneurysms enlarged, 2 disappeared, and 8 unchanged by the follows-up examinations. 4 cases had bleeding from unruptured cerebral aneurysm, and three of these bleeding were fatal. One of them was operated on and had an uneventful course.
At present, unruptured cerebral aneurysms are becoming on increasing important neurological problems. It is very significant to clarify the natural history of this lesion.
