Long-term Angiographic Recurrences After Selective Endovascular Treatment of Aneurysms with Detachable Coils

Background And Purpose: Our aim in this study was to assess the incidence and determining factors of angiographic recurrences after endovascular treatment of aneurysms.

Methods: A retrospective analysis of all patients with selective endosaccular coil occlusion of intracranial aneurysms prospectively collected from 1992 to 2002 was performed. There were 501 aneurysms in 466 patients (mean+/-SD age, 54.20+/-12.54 years; 74% female). Aneurysms were acutely ruptured (54.1%) or unruptured (45.9%). Mean+/-SD aneurysm size was 9.67+/-5.91 mm with a 4.31+/-1.97-mm neck. The most frequent sites were basilar bifurcation (27.7%) and carotid ophthalmic (18.0%) aneurysms. Recurrences were subjectively divided into minor and major (ideally necessitating re-treatment). The most significant predictors of angiographic recurrence were determined by logistic regression. These results were confirmed by chi2, t tests, or ANOVAs followed, when appropriate, by Tukey's contrasts.

Results: Short-term (< or =1 year) follow-up angiograms were available in 353 aneurysms (70.5%) and long-term (>1 year) follow-up angiograms, in 277 (55%), for a total of 383 (76.5%) followed up. Recurrences were found in 33.6% of treated aneurysms that were followed up and that appeared at a mean+/-SD time of 12.31+/-11.33 months after treatment. Major recurrences presented in 20.7% and appeared at a mean of 16.49+/-15.93 months. Three patients (0.8%) bled during a mean clinical follow-up period of 31.32+/-24.96 months. Variables determined to be significant predictors (P<0.05) of a recurrence included aneurysm size > or =10 mm, treatment during the acute phase of rupture, incomplete initial occlusions, and duration of follow-up.

Conclusions: Long-term monitoring of patients treated by endosaccular coiling is mandatory.