Endovascular Treatment of Complex Distal Posterior Cerebral Artery Aneurysms with the Pipeline Embolization Device

Objective To assess the safety and efficacy of the Pipeline Embolization Device (PED) for endovascular treatment of complex, distal posterior cerebral artery (PCA) aneurysms. Methods We conducted a retrospective review of patients who underwent endovascular treatment of complex PCA aneurysms with PED from November 2012 to December 2015. A total of 4 patients were identified and treated. Twelve-month angiographic and clinical follow-up was available for all patients. Results Mean aneurysm size (largest diameter) was 10.0 mm, and all aneurysms originated at the P2 segment or beyond. Technical success was achieved in all patients. All patients were treated with a single PED; adjunctive intrasaccular coil was also placed in one patient. All patients achieved a favorable postprocedural outcome (modified Rankin Scale score = 0) with no new neurologic deficits. No patients experienced neurologic complications or perforator infarction, and presenting symptoms resolved in all patients. Follow-up cerebral angiography at 12 months in 3 patients showed complete occlusion (Raymond-Roy Occlusion Classification class 1) and minimal residual aneurysm filling (Raymond-Roy Occlusion Classification class 2) in 1 patient. A small degree of focal stenosis was present in 2 patients within the PED at 12-month follow-up that was associated with mild decrease in flow within the distal PCA branches. Conclusions PED use provides a practical and viable treatment option for complex, distal PCA aneurysms. Based on our limited institutional experience, PED use for treatment of complex, distal PCA aneurysms in select patients appears safe and effective.