Introduction: As the paradigm of aneurysm treatment has changed to either coiling or clipping of aneurysms, a common question is whether clipping of previously coiled and recurrent aneurysms is safe. Previously ruptured and embolized ACOM aneurysms have been found to have a high recurrence rate by our group and we have proposed that stent assisted coiling or clipping may be potential ways to retreat these aneurysms. We looked at the complication rate from clipping of previously coiled ACOM aneurysms compared to the complication rate from clipping previously untreated ACOM aneurysms.

Methods: In an IRB approved study, we looked retrospectively at 489 aneurysms clipped from 2007-2015 at the Cleveland Clinic. 84 patients were ACOM aneurysms that were clipped. 6 of these patients had been previously coiled. Complications were measured at time of surgery, <30 days, 6 years, 1 year and 5 years and included stroke, seizures, subdural collections, and wound infections.

Results: 1 patient of the 6 with aneurysms that had undergone clipping post embolization had a subdural fluid collection that resolved over time. 14 patients of 78 treated primarily by clipping had complications including 6 wound infections, 1 developed seizures, and 5 strokes with one being atrial fibrillation related. There was no statistical difference between the number of complications in the clipping post coiling group (17%) compared to the primary clipping groups (18%).

Conclusions: Though this study is limited by being retrospective and having a small number of patients in the previously coiled group, our data suggests that clipping of previously coiled ACOM aneurysms is as safe as clipping primarily coiled aneurysms.

Patient Care: This study will guide physicians in retreatment options for patients with recurrent ACOM aneurysms.

Learning Objectives: Clipping of previously coiled ACOM aneurysms is as safe as clipping primarily.

References: Moore, NZ, M. Lang, A. Bauer, S. John, R. Cerejo, P. Rasmussen, M. Bain. Rehemorrhage and Recurrence Rates of ACOM Aneurysms Post Embolization. Submitted for publication to Journal of Neurosurgery.