Endovascular treatment of spontaneous intracranial fusiform and dissecting aneurysms: outcomes related to imaging classification of 309 cases

Abstract Objective This study aimed to propose a modified classification of spontaneous intracranial dissecting aneurysms (IDAs) and to guide the treatment for IDAs. Methods Between January 2010 and December 2015, 3183 consecutive patients were referred to our department for endovascular treatment of a cerebral aneurysm and 309 patients harboring 323 spontaneous IDAs were identified from them. Based on a modified imaging classification, spontaneous IDAs were classified into four subtypes: classic dissecting aneurysm, segmental ectasia, dolichoectatic dissecting aneurysm, and large mural bleeding ectasia. The logistic regression analysis was performed to find predictors of clinical outcome of patients. Results Of the 323 IDAs, 216 (66.87%) were treated with stent-assisted coiling, 47 (14.55%) with internal trapping, and 60 (18.58%) with sole stenting. Of the 309 patients, 8 (2.59%) suffered intraoperative complications and 40 (12.94%) had postoperative complications; 9 patients (2.79%) died and 1 (0.32%) had severe disability. The mean duration of clinical follow-up of the 309 patients was 10.40 months (range, 3–72 months). Imaging follow-up was available for 262 patients (274 IDAs) with a mean duration 7.10 months (range, 3–60 months), and 24 (9.16%) aneurysm recurrences was noted. Aneurysm type was the only independent predictor of different outcome by logistic regression analysis ( P =0.004). Conclusions There was a strong relationship between the subtypes of the spontaneous IDAs and their clinical course. This classification was confirmed as helpful in assessing the prognosis of patients and guiding their treatment.