Introduction The ruptured aneurysm at dorsal wall of internal carotid artery (ICA) has therapeutic dilemma. Nowadays, endovascular procedure with flow diversion using stents is considered as new emerging therapeutic modality. We retrospectively review our cases.

Material and method From 2010 Aug. to 2014 Dec, total 12 cases of ruptured aneurysm at dorsal wall of ICA, treated with endovascular procedures were enrolled. The saccular aneurysm was defined as same or higher height compared to neck. The blister aneurysm was defined as 1) wider neck compared to height, 2) no discrete neck, 3) retained dye filling into sac, 4) irregular contour. The treatment modalities and final neurologic outcome were assessed.

Results The mean age was 49.8 years and female was dominant (10 patients). The saccular pattern showed in 3 cases (25%) and blister type was 9 cases (75%). In saccular type, only 1 case used stent (33%). In blister type, all cases performed stent assist coiling. The average number of stent was 2.67. The earlier 4 case (2010–2011) and later 5 cases (2012–2014) showed average 1.5 stents with loose packing density and average 3.2 stents with dense one, respectively. In saccular group of 3 cases, the modified Rankin scales at 6 month were 0, 0 and 6 (brain edema). In blister group of 9 cases, those were 0 (6 cases; 67%), 2 (1 case; 8.3%) and 4 (2 cases; 16.7%). The earlier 4 cases showed poor outcome compared to later group, but the number of stent and coil packing density did not correlated with final outcome.

Conclusion Compared to saccular type, the blister type of ICA dorsal wall aneurysm showed definite predominance of stent assist coiling. The results of endovascular procedures of both types are satisfactory. In blister type, the final outcome do not completely correlated with flow diversion concept.

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