Object Blood blister-like aneurysms (BBA) are aneurysms arising from the non-branching arterial trunk, which are usually small and located at the dorsal wall of supraclinoid internal carotid artery (ICA). These aneurysms are quite dangerous due to their fragile neck. This paper aims to evaluate the application of endovascular treatments in the treatment of BBA.

Methods Four hundred fifty-one patients diagnosed with aneurysmal SAH between Aug. 2010 and Dec. 2014 were collected at the Catholic University of Korea, Saint Vincent’s hospital. Thirteen patients had ICA dorsal wall aneurysms. A retrospective review of the aneurysm database in our institution identified 12 patients carrying ICA dorsal wall aneurysm planned to be treated by endovascular treatments. The clinical characteristics, angiographic outcome, and follow-up results were reviewed. Clinical characteristics included age, gender, Hunt and Hess grade, modified Fisher grade, type of treatment (coil embolization, surgical clipping), aneurysm type.

Results Stent-assisted coil embolization was successfully performed in 10 cases (83.3%). In terms of the stent usage, 2 patients were treated with single stent (16.6%), 2 patients were treated with double stent (16.6%), and 6 patients were treated with triple stent (50%). Six patients had rapid configurational changes during the treatment course (50%). Because rapid growth of this type of aneurysm had high re-bleeding tendency, we decided multiple stent deploying. In spite of multiple stent-assisted coil embolization, one patient occurred regrowth. All patients were followed up angiographically, and regrowth was observed in two patients (16.6%), one case was treated by further endovascular treatments without complications and another case was observed due to obliteration by thrombosed. The modified Rankin scale (mRS) score in living patients at discharge was 0 in five cases, 1 in one case, 3 in one case, and 4 in two cases. One patient died of severe brain edema. The mRS score at 1–57 months’ follow-up was 0 in eight cases, 2 in one case, and 4 in two cases.

Conclusions Because rapid growth of aneurysm had high re-bleeding tendency, we had done multiple stent deploying. The results of endovascular procedures of this type of aneurysm are satisfactory. But we don’t know yet, how many stents are enough. However multiple stent-assisted coil embolization can be considered as an alternative treatment option for rapid-growing dorsal wall aneurysms.

Disclosures D. Lee: None. J. Sung: None. J. Huh: None. Y. Ihn: None. S. Lee: None.