Background Current endovascular techniques have been widely used to treat paraclinoid aneurysms.

Methods From January 2009 to December 2011, 126 consecutive patients with 142 saccular paraclinoid aneurysms were treated with endovascular embolization at our institute. A retrospective review of the clinical and imaging data was performed.

Results Of the 142 aneurysms, 121 (86.2%) had small while 21 (14.8%) had large fundus size. 83 aneurysms (58.5%) were narrow necked and 59 (41.5%) were wide necked. The dome–neck ratio was favorable in 26 aneurysms (18.3%) and unfavorable in 116 (81.7%). 24 aneurysms (16.9%) were managed with coil embolization and 118 (83.1%) with a stent assisted coiling technique. Immediate angiography demonstrated complete occlusion in 62 (43.7%), neck remnant occlusion in 47 (33.1%), and residual aneurysm occlusion in 33 (23.2%) aneurysms. The overall recurrence rate in the 112 aneurysms with angiographic follow-up (8.88±3.40 months, mean±SD) was 12.5%. Of the 14 recurrent aneurysms, 10 were managed with endovascular treatment (six by stent assisted coiling, four by coiling) while four are under observation. There were six (4.3%) procedural complications during 137 procedures. Clinical follow-up was available for 119 patients (94%) with a follow-up time of 16.6±13.6 months, and the majority (98%) had a modified Rankin scale score of 0–1.

Conclusions The stent assisted coiling technique is effective for the treatment of paraclinoid aneurysms. Small paraclinoid aneurysms (≤10 mm) are suitable for endovascular treatment, with a low rate of recurrence. In contrast, large paraclinoid aneurysms (>10 mm) treated with current endovascular techniques exhibited a high rate of recurrence.