Background Over the past decade, coil embolization of intracranial aneurysm has proved to be both safe and effective. A major concern coil embolization is the recurrence of aneurysm requiring re-treatment. Low coil packing leading to coil compaction has been associated with a higher risk of aneurysm recurrence. In this study, we evaluate packing density, aneurysm recurrence and complication rates associated with different endovascular techniques.

Methods The prospectively collected data from the SMART registry was interrogated. Only patients with unruptured aneurysms were included in these analyses. Patients were divided into four groups according on the endovascular treatment modality used: group 1 (primary coiling), group 2 (balloon assisted coiling), group 3 (stent assisted coiling), and group 4 (balloon and stent assisted coiling). Baseline characteristics, aneurysm features, packing density, complication and recurrence rates were compared between the groups.

Results Total of 607 patients were included in this study. Of those, 240 were in group 1, 68 in group 2, 287 in group 3, and 22 in group 4. Median age was 61 (IQR, 53–69), and 75% were females (table 1). There was no difference in aneurysm size, or duration of coil deployment. Wide neck aneurysms were more prevalent in groups 3 and 4 compared to groups 1 and 2 (group 3; 72.8%, group 4; 81.8%, group 1; 57.9%, and group 2; 61.8%, P=0.008). While there was no difference in packing density between the groups at initial treatment, at 1-year, complete occlusion (RR class 1) was achieved at a higher rate in groups 3 and 4 (75%) compared to 1 (62.6%) and group 2 (42.6%) P<0.001. There was higher rate of device related complications within 24 hours in group 4 compared to groups 1, 2 and 3 (group 4 13.6%, groups 1,2 and 3; 1.3%, 4.4%, 2.4% respectively, P=0.004).

Conclusions In patients with unruptured intracranial aneurysms, the use of primary coiling and balloon assisted coiling was associated with similar packing density to stent or stent plus balloon assisted coiling, though with lower rates of aneurysm obliteration at 1 year. Combined stent and balloon assisted coiling was associated with higher rates of immediate complications. Further prospective studies are warranted to confirm our findings.

Disclosures S. Al Kasab: None. E. Almallouhi: None. M. Anadani: None. M. Sattur: None. A. Spiotta: None.