Multiple intracranial aneurysms in elderly patients.

The clinical characteristics of elderly patients with multiple intracranial aneurysms were studied. A total of 481 patients, in whom the exact location of their ruptured aneurysms could be confirmed, were classified into two age groups, that is, those aged 59 years or younger (group 1: 247 cases, 51%) and those aged 60 years or older (group 2: 234 cases, 49%). The incidences of multiple aneurysms were 30% for group 1 and 27% for group 2. This difference is statistically not significant. The rate of multiple aneurysms was less frequent in males than in females in group 2, whereas no difference could be found in group 1. The age distribution of patients with multiple aneurysms was basically similar to that of patients with single aneurysms. While the highest rupture rate was observed in the anterior communicating artery aneurysms of both groups, this tendency was more prominent in group 2 (79%) than in group 1 (59%). The rupture rates for other sites in group 2 were 50% for distal anterior cerebral artery aneurysms, 40% for internal carotid artery aneurysms and 28% for middle cerebral artery aneurysms. The pattern of surgical outcome showed no major differences between multiple and single aneurysms in either group 1 or 2. However, group 1 had better surgical results than group 2. Even though the surgical outcome for multiple aneurysms in elderly patients was satisfactory, awareness of the probability of rupture at each site is helpful, especially when it is necessary to decide whether unruptured aneurysms should be operated on or not.