Introduction: Blister aneurysms (BA) are a rare subtype of intracranial aneurysms. Whether treated with surgical or endovascular approaches, these fragile aneurysms carry an elevated risk of morbidity due to their increased likelihood of intraprocedural rupture.

Methods: We conducted a systematic review of all ruptured internal carotid BA papers between 1980 and 2012. We restricted our analysis to papers, which included individual level patient data describing demographics, presentations, aneurysm location, management and outcomes.

Results: We have identified eighty-one patients with sufficient data to permit analysis. 80 % were female. The mean age at presentation was 52 years (range 24-74). 25 % were poor clinical grade. Fifty-four were treated surgically (direct surgical repair, wrapping, trapping with or without bypass) and twenty-seven were treated using endovascular methods (coiling, stent assisted coiling, stent alone, or trapping/vessel occlusion). Intraprocedural rupture rates were relatively high at 33 %. While definitive conclusions are difficult, there was a trend towards improved outcomes with both surgical and endovascular trapping approaches.

Conclusions: BAs remain challenging vascular lesions. Trapping may avoid some of the morbidity associated with direct repair strategies. Further comparative studies are needed to define the optimal approach to these aneurysms.

Patient Care: by approving the best treatment option for blister aneurysm will decrease morbidities and mortalities of this disease .

Learning Objectives: Studies addressing proper management of BBA are multiple one center focused small trials show different techniques, opinions and recommendations, indicate the need to review all BBA papers to find out the best treatment option for this kind of aneurysm.

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