Analysis Supports EVAR for Small Intracranial Aneurysms

January 1, 2010—In Stroke, Waleed Brinjikji et al published findings from a meta-analysis of published studies on the endovascular treatment of very small intracranial aneurysms, including 71 patients treated at the Mayo Clinic and Medical School in Rochester, Minnesota (2010;41:116–121).

According to the investigators, their findings suggest that treatment of very small aneurysms is feasible and effective in > 90% of treated aneurysms. However, the risk of periprocedural rupture is higher than that reported for larger aneurysms. Similarly, the combined rate of periprocedural mortality and morbidity is not negligible (7.3%) and should be considered when considering the best therapeutic option for these aneurysms, the investigators concluded.

As detailed in Stroke, the investigators conducted a computerized MEDLINE search of the literature for reports on the treatment of intracranial aneurysms with a maximum dimension of 3 mm by using the search terms small, tiny, intracranial aneurysm, endovascular, and coil. Seven studies, including the Mayo Clinic's consecutive case series of 71 intracranial aneurysms, were included in this study. The investigators extracted information regarding intraoperative complications, procedural mortality and morbidity, immediate- and long-term angiographic outcomes, and retreatment rate. The meta-analysis was performed with the statistical package Comprehensive Meta-Analysis (Biostat, Inc., Englewood, NJ).

The investigators found that approximately 61% of the aneurysms in this meta-analysis presented as ruptured, whereas 39% of the aneurysms were unruptured. The procedural rupture rate for very small aneurysms was 8.3% (95% confidence interval [CI], 6.0%–11.4%). The mortality rate due to procedural rupture was 2.4% (95% CI, 1.2%–4.7%). The morbidity rate due to thromboembolic complications was 1.9% (95% CI, 0.9%–3.9%). Subarachnoid hemorrhage within 1 month of treatment occurred in 1.6% (95% CI, 0.6%–3.7%) of cases. There was no statistically significant difference between unruptured and ruptured aneurysms for any of these outcomes, the investigators reported.