A long-term follow-up study in direct cerebral aneurysm surgery.

A long-term follow-up study covering between one and twenty-two years after surgery was carried out on 177 patients with direct operations for cerebral aneurysms. Rebleeding was detected in five out of 18 patients with incomplete operations; one patient within 6 months and four patients within 5 to 8 years after surgery. The rebleeding rate of incompletely operated patients in the first decade was similar to that of untreated patients with ruptured aneurysms. This suggests that wrapping, coating and incomplete clipping procedures provide some protection against rebleeding in the first 6 months but little in the period extending beyond 5 years after surgery. Showing two types of newly-formed aneurysms after complete surgery and enlarged residual aneurysms after incomplete surgery, the possibility of rebleeding from these aneurysms is discussed in the present report.