Multiple cerebral aneurysms--a reappraisal.

254 consecutive cases of angiographically demonstrated intracranial cerebral aneurysms occurring over a three year period were reviewed with specific reference to aneurysm multiplicity, site, patient age and the presence of infundibular abnormalities. The overall incidence of multiple aneurysms was 44.9%. Female patients accounted for 66.5% of all aneurysm cases. The incidence of multiplicity was higher in women (51.5%) than men (31.7%) and overall was higher in patients over 40 years of age (52.8%) compared to those under this age (26.3%). Infundibula occurred in 27.2% of all patients and 9.45% of all patients demonstrated infundibular dilatation of the origin of the posterior communicating artery.