Endovascular Treatment of Basilar Tip Aneurysms with Guglielmi Detachable Coils: Predictors of Immediate and Long-term Results with Multivariate Analysis—6-year Experience

Abstract

To analyze anatomic and clinical results and factors predictive of outcome in treatment of basilar tip aneurysms with Guglielmi detachable coils (GDCs). During 6 years, 55 unselected consecutive saccular aneurysms in 53 patients (mean age, 47 years) were treated with GDC occlusion. Forty-one (75%) aneurysms were ruptured (Hunt-Hess and Fisher grades were assigned in patients); 14 (25%), unruptured. Clinical and angiographic evaluations were performed 6 months after treatment and during follow-up (mean follow-up, 2 years). Multivariate analysis was used to determine factors predictive of outcome. GDC occlusion was a success in 52 (95%) aneurysms, a failure in two (4%), and not attempted in one (2%). Occlusion at final follow-up, evaluated in 44 aneurysms, was complete in 34 (77%), near complete in four (9%), and incomplete in six (14%). At 6-12 months, mean aneurysmal occlusion rate significantly worsened because of revascularization (P <.001) but improved at final follow-up because of reembolization in 10 aneurysms (P =.009); it remained stable (P =.351) between initial and final follow-up. Multivariate binary logistic regression indicated that before treatment started, aneurysmal neck size was the only independent predictor of initial occlusion rate (P =.002) and revascularization (P =.004). After the initial procedure, sac size and initial occlusion rate were independent predictors of revascularization (P =.004 and.008, respectively), irrespective of neck size. Occlusion rate at 6-12-month follow-up was the only independent predictor of that at final follow-up (P =.021), regardless of shape of aneurysm. Overall morbidity was 2% (one of 51); mortality, 6% (three of 51). Mortality correlated significantly with Hunt-Hess grade 4 at admission (P =.003) and incidence of vasospasm (P =.058). GDC occlusion proved to be a safe effective therapeutic alternative to surgery in patients with ruptured or unruptured basilar tip aneurysms. Morphologic and clinical factors were respectively identified as predictors of the optimal anatomic and clinical outcomes.