Pipeline flex embolization device for the treatment of large unruptured posterior circulation aneurysms: Single-center experience.

PURPOSE To investigate the safety and effect of the Pipeline Embolization Device (PED) Flex device in the treatment of large unruptured posterior circulation aneurysms in a single center. MATERIALS AND METHODS Patients with large unruptured posterior circulation aneurysms which were treated with the PED Flex device were enrolled. The clinical, endovascular and follow-up data were analyzed, and the O'Kelly-Marotta (OKM) grading system was used to assess the aneurysm occlusion status. RESULTS Fourteen patients with 14 large posterior circulation aneurysms who were treated with the PED Flex device were enrolled. The maximal diameter of aneurysm was 17.0 ± 3.9 mm. Fourteen PED Flex devices were deployed in 14 patients, with a technical success rate of 100%. All stents covered the aneurysm neck with good wall adherence and patent parent artery. Ten (71.4%) aneurysms were treated with a single PED Flex device each, and four (28.6%) patients experienced additional coiling. No neurological complications occurred in the periprocedural period. The mRS was 0 in eleven (78.6%) patients, 1 in two (14.3%), and 2 in one (7.1%) at discharge. All patients were followed up at 6-28 months (median 18), with an mRS score of 0 in all patients. Twelve (85.7%) patients experienced digital subtraction angiography 6-28 (median 18) months after the embolization procedure, and the OKM grade was D in nine (75%), C in two (16.7%), and B in one (8.3%). CONCLUSION The Pipeline Flex Embolization Device can be safely applied to treat large unruptured posterior circulation aneurysms with a high complete aneurysm occlusion rate at follow-up.