Mortality and Morbidity of Surgery for Unruptured Intracranial Aneurysms

Abstract

Background and Purpose-Greater availability and improvement of neuroradiological techniques have resulted in more frequent detection of unruptured aneurysms. Because prognosis of subarachnoid hemorrhage is still poor, preventive surgery is increasingly considered as a therapeutic option. Elective surgery requires reliable data on its risks. Therefore, we performed a meta-analysis on the mortality and morbidity of surgery for unruptured intracranial aneurysms. Methods-Through Medline and additional searches by hand, we retrieved studies on clipping of unruptured (additional, symptomatic, or incidental) aneurysms published from 1966 through June 1996. Two authors independently extracted data. We used weighted linear regression for data analysis. Results-We included 61 studies that involved 2460 patients (57% female; mean age, 50 years) and at least 2568 unruptured aneurysms (27% Ͼ25 mm, 30% located in the posterior circulation). Mortality was 2.6% (95% confidence interval [CI], 2.0% to 3.3%). Permanent morbidity occurred in 10.9% (95% CI, 9.6% to 12.2%) of patients.Postoperative mortality was significantly lower in more recent years for nongiant aneurysms and aneurysms with an anterior location; the last 2 characteristics were also associated with a significantly lower morbidity. Conclusions-In studies published between 1966 and 1996 on clipping of unruptured aneurysms, mortality was 2.6% and morbidity was 10.9%. In calculating the pros and cons of preventive surgery, these proportions should be taken into account. (Stroke. 1998;29:1531-1538.)

Cost-effectiveness of preventive treatment of intracranial aneurysms

“…We used both ISUIA data and results from reviews on mortality and morbidity rates of preventive treatment in general. 4,18,19 We used a treatment-related mortality rate of clipping of 1.8% and a morbidity rate of 5.6%. 4,18 For coiling, we used a treatment-related mortality rate of 0.6% and a morbidity rate of 7%.…”

“…4,18,19 We used a treatment-related mortality rate of clipping of 1.8% and a morbidity rate of 5.6%. 4,18 For coiling, we used a treatment-related mortality rate of 0.6% and a morbidity rate of 7%. 19 We assumed that half of the patients with surgical morbidity and onethird of patients with endovascular morbidity became moderately to severely disabled.…”

“…19 We assumed that half of the patients with surgical morbidity and onethird of patients with endovascular morbidity became moderately to severely disabled. 4,18,19 Risk of development of a regrowth, reopening, or de novo aneurysm. After clipping, a regrowth rate of 0.3 to 0.5% per year has been reported.…”

The Merits of Endovascular Coil Surgery for Patients with Unruptured Intracranial Aneurysms

“…The ISUIA reported that 11% of patients with unruptured aneurysms presented with ischemic cerebrovascular disease 12) . Nagashima et al 10) .…”

Association analyses confirming a susceptibility locus for intracranial aneurysm at chromosome 14q23

“…Despite advances in diagnostic and treatment techniques, the prognosis of SAH remains unimproved. Prophylactic treatment by surgical clipping or endovascular coiling of an aneurysm prior to its rupture can reduce mortality and morbidity (Henkes et al 2004; International Study of Unruptured Intracranial Aneurysms Investigators 1998; Raaymakers et al 1998). However, it is costly and timeconsuming to detect unruptured aneurysms by performing periodic screening examinations by magnetic resonance angiography (MRA).…”