Flow Diversion Using Pipeline Embolization Device (PED) for Intracerebral and Extracerebral Pseudoaneurysms: A Systematic Review and Meta-analysis of the Current Literature

Introduction: Pseudoaneurysms are complex lesions associated with high incidence of rupture and mortality. Flow diverters have been proposed as an alternative treatment to preserve the flow through the parent artery. We investigated the safety and the short ( < 1 year) and long-term (≥1 year) aneurysm occlusion rates following the treatment of intracerebral and extracerebral pseudoaneurysms using the Pipeline Embolization Device (PED).

Methods: An electronic database search for full-text English articles was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Studies of any design with at least 4 patients with intracranial or extracranial pseudoaneurysms treated with PED were included in our analysis. The primary safety endpoint was the incidence of post-procedural complications. The primary efficacy endpoint was the complete aneurysmal occlusion rate.

Results: We included 9 studies with a total of 90 patients harboring 96 pseudoaneurysms. The mean age was 38.2 years, and 37.8% were women. The mean pseudoaneurysm size was 4.9 mm. Most pseudoaneurysms were unruptured, and the etiology was traumatic brain injury in 33.3%, spontaneous in 21.9%, and iatrogenic injury in 19.8%. Twenty-nine(30.2%) pseudoaneurysms were located in the cervical ICA, while 15.5% and 12.5% were in the petrous and cavernous segments of ICA, respectively. Thirty-three pseudoaneurysms were treated with ≥ 2 devices, and 8 received adjunctive coils. The mean clinical and angiographic follow-ups were 10.6 and 12.8 months, respectively. The short-term and long-term complete occlusion rate was, respectively, 79%(95%,CI 66%-88%, p=0.82) and the 84%(95%,CI 70%- 92%, p=0.95). Complication rates were 8 % for iatrogenic dissection (95%,CI 3%-16%, p=0.94), 10% for silent thromboembolism(95%,CI 5%-21%,p=0.77) and 12% for symptomatic thromboembolism (95%,CI 6%-23%, p=0.48). No hemorrhage was noted following treatment at the last follow-up.

Conclusion : Symptomatic stroke was the most represented complication, followed by silent thromboembolism. The complete occlusion rate of pseudoaneurysms treated with PED was high and increased over time.