Factors affecting the durability of coil embolization for intracranial aneurysms

Abstract

OBJECTIVE: Endovascular coil embolization for ruptured and unruptured intracranial aneurysms has proven to be safe and effective treatment modality. However, its long term durability still remains to be improved. This study aims to depict factors affecting the durability of coiled aneurysms by analysis of patient characteristics, aneurysm factors, and treatment outcome. METHODS: Data for patients treated with endovascular coil occlusion in Yonsei university medical center between 2005 and 2009 were retrospectively reviewed. Patient and aneurysm characteristics, treatment outcome, and follow up results were collected and statistically analyzed to determine factors that affect in durability of coil embolization.RESULTS: 228 aneurysms in 208 patients had adequate follow up data for evaluation of durability after coil embolization. 37 (16.2%) aneurysms recurred after an average of 19.5 months follow up. Patient factor associated with durability was treatment after rupture. Aneurysm factors such as size, depth, volume of aneurysm, aspect and bottleneck ratio were associated with durability. Treatment factors that were associated with durability were length of embolized coil, packing density, completeness of occlusion, and use of stent. Follow up duration and angiography as mode of follow up was also related to durability. Multivariate logistic regression identified volume of aneurysm, treatment after rupture, use of stent, and angiography as mode of follow up as significant predictors affecting durability after coil embolization.CONCLUSION: The possible risk factors that affect the durability of coil embolization were larger aneurysm volume, treatment after rupture, and absence of stent remodeling. These factors may be considered for clinicians in case of deciding for coil embolization of intracranial aneurysms and long term follow up may be needed in presence of such risk factors