Towards a new treatment paradigm for ruptured blood blister-like aneurysms of the internal carotid artery? A rapid systematic review

BACKGROUND AND PURPOSE: Owing to their peculiar features and rare occurrence, ruptured blood blister-like aneurysms (BBAs) of the internal carotid artery are challenging by both surgical and endovascular approaches and their proper management is uncertain. We therefore aimed to define the currently optimal treatment of ruptured BBAs in terms of mortality, outcome, rebleeding, and recurrence. METHOD: An in-depth search of electronic databases, gray literature and internet resources for ruptured BBAs was performed and complemented by data retrieval during neurosurgical congresses. Clinical and radiological characteristics, intervention details, outcomes, and the impact factor of the source journal were pooled. RESULTS: The pooled cohort comprised 311 patients. Neither surgical nor endovascular methods had an impact on clinical outcome, aneurysm regrowth, remote bleeding, or complication rate. By contrast, aneurysm clipping was a predictor of intraoperative bleeding (OR 6.5; 95% CI 1.2 to 34.3), and stent-assisted coiling increased the likelihood of a second treatment (OR 4.1; 95% CI 1.3 to 13.1), its conversion to another modality (OR 4.7; 95% CI 1.4 to 16.0), and incomplete aneurysm obliteration (OR 2.6; 95% CI 1.0 to 6.6). Higher impact journals were more likely to publish papers on endovascular techniques, particularly flow-diverter stents. CONCLUSIONS: None of the methods is unequivocally superior. Considering its inefficiency, stent-assisted coiling should be undertaken with caution. A time-delimited systematic review is needed to establish the most accurate treatment for ruptured BBAs.