MULTIPLE INTRACRANIAL ANEURYSMS IN A DEFINED POPULATION - PROSPECTIVEANGIOGRAPHIC AND CLINICAL-STUDY

MULTIPLE INTRACRANIAL ANEURYSMS (MIA) have been detected in up to one- third of patients with cerebral aneurysms. Three main external factors influence these figures as follows: the quality of angiographies, the quantity of vessels studied, and referral policy. In a 1-year prospec tive study, we determined the incidence of MIA in a defined catchment area in East Finland by investigating all of the patients with intracr anial aneurysms with panangiography. In 114 unselected patients, a tot al of 170 intracranial aneurysms were detected, and, of these, 39 (34% ) harbored MIA. In contrast to most other reports, there was a male pr edominance in patients with MIA, and half of these men had hypertensio n. Intracavernous carotid and pericallosal aneurysms were more frequen t in patients with MIA. The number of asymptomatic vertebrobasilar ane urysms was extremely low, and most of the nonruptured aneurysms were f ound in bilateral carotid angiograms. In spite of the active search, t he proportion of vertebrobasilar aneurysms remained at 6%. Although ou r surgical policy was most active, one-third of the asymptomatic aneur ysms remained untreated, mainly because of the poor condition of the p atient.