Patient and aneurysm characteristics in multiple intracranial aneurysms

Multiple aneurysms occur in up to one-third of people with intracranial aneurysms. Of such patients, epidemiological data, clinical information, and aneurysm characteristics (of both unruptured and ruptured aneurysms in the same patients) were gathered in this retrospective review.

Ninety-nine patients operated on for multiple intracranial aneurysms at the Department of Neurosurgery, University Hospital Zurich, Switzerland, between 1994 and 2003 were assessed, 90% with subarachnoid hemorrhage (SAH), 10% with incidental aneurysms.

The female to male ratio was 3:1, median age was 53 years. SAH symptoms included acute headache (74%), decrease of consciousness (54%), nausea and vomiting (40%), epileptic seizure (11%). Neurological signs were meningism (40%), cranial nerve paresis (12%), none (28%). Chronic headache was the major complaint (40%) in patients with incidental aneurysms, 20% had paresis of extraocular muscles. History of smoking and hypertension was present in 47% and 35%. There were 265 aneurysms (median number per patient, 2; range, 2-8), 95% were small (< or = 10 mm), 4.5% large, 0.5% giant (> 25 mm); 34% were ruptured, 66% unruptured (median size, 7 mm vs. 4 mm; p < 0.0001). Most aneurysms (27%) were on the middle cerebral artery bifurcation. Most ruptured aneurysms (18%) were on the anterior communicating artery and were 10 mm or smaller. Eighty-one percent of patients had (non-surgery related) SAH complications: cerebral vasospasm (44%), post-SAH hydrocephalus (36%), cerebral infarction (36%), intracerebral (25%) and intraventricular (21%) bleeding. Glasgow Outcome Scale score at 3 months was 4 or 5 in 73%.

Ruptured aneurysms were significantly larger than unruptured ones. Although discussed controversially, most of our population's ruptured aneurysms were 10mm or smaller in size. Considering this, our study may contribute to improve the management of patients with intracranial aneurysms.