1365 Enigmas of the Supraclinoidal Internal Carotid Artery: Meta-Analysis of Microsurgical Versus Endovascular Interventions for Blood Blister-Like Aneurysms

INTRODUCTION: Blister aneurysms (BAs) of the internal carotid artery (ICA) have high associated mortality and are challenging owing to their friable wall and poorly defined neck. Microsurgical and endovascular treatment options have been suggested, including bypass of the parent vessel to exclude the aneurysm. METHODS: Three databases were queried for primary studies comparing microsurgery to endovascular therapy for BAs of the ICA. All relevant studies published between 2000 and 2023 were eligible for inclusion. The following primary data points were extracted from each study: specific therapy employed, perioperative/periprocedural complications, and postoperative functional status (favorable versus unfavorable modified Rankin Score [mRS]).Ultimately, relevant data from all included studies were pooled for meta-analysis using the Mantel-Haenszel method with random-effects modeling. RESULTS: Among the 519 cases reported across 26 studies, 182 (32.6%) were surgical, while 337 (67.4%) involved endovascular treatment. The cohort's mean age was 47.0 years, and 248 (47.8%) patients were female. Functional outcomes were comparable between groups, with 83% of surgically treated patients and 85% of endovascularly-treated patients achieving a favorable outcome (p>0.05). However, across six studies directly comparing microsurgery to endovascular therapy, endovascular treatments demonstrated a higher rate of favorable (mRS = 0-2) functional outcomes (OR=2.49, 95% CI 1.12-5.55, p=0.02). CONCLUSIONS: The present meta-analysis suggests endovascular therapy is associated with increased odds of favorable functional outcomes, likely explained by the introduction of PEDs for flow diversion and the select use of stent-assisted coiling with overlapping stents.