Long-term outcome of surgically treated unruptured cerebral aneurysms.

We report the surgical morbidity and mortality and the results of statistical analysis based on the long-term outcome (average 50.1 months) of 69 patients with unruptured cerebral aneurysms. These patients harbored a total of 76 unruptured cerebral aneurysms, 72 larger than 3 mm in diameter. All the latter were surgically treated. There was no operative mortality. Operative morbidity occurred in 5 patients (7.2%), including hemiplegia in 2 from obliteration of perforator vessels, transient memory impairment in 2 due to brain retraction, and transient oculomotor nerve palsy in 1 patient resulting from an unknown etiology. During the observation period, 53 patients (76.8%) had a good or fair outcome, 11 (15.9%) had a poor outcome, and 5 (7.3%) died from causes unrelated to the aneurysms, such as pneumonia, gastrointestinal bleeding, and heart failure. The 5-year survival rate was 94%. Statistical analysis of the long-term outcome of all patients showed no significantly important factor influencing long-term morbidity. Prophylactic surgery of aneurysm is recommended for low-risk patients who may develop eventual rupture of an aneurysm, but perforator vessels around the aneurysm should be preserved, clips should be properly placed, and brain retraction should be minimized.