Clinical and Anatomical Characteristics of Perforator Aneurysms of the Posterior Cerebral Artery: A Single-Center Experience

Abstract

Introduction: Posterior cerebral artery (PCA) aneurysms represent up to 1% of all cerebral aneurysms. P1-P2 perforator aneurysms are thought to be even less prevalent and often require complex treatment strategies due to their anatomical and morphological characteristics, with risk of a perforator infarct. We studied the treatment of P1-P2 perforator aneurysms in a single-center cohort from a high-volume tertiary center, reporting clinical and anatomical characteristics, treatment strategies, and outcomes. Methods: A retrospective analysis of adult patients with a P1-P2 perforator aneurysm who presented at our institution between January 2000 and January 2023 was performed. The patients were analyzed for demographics, clinical presentation, imaging findings, treatment techniques, outcomes, and complications. Subgroup analyses between ruptured versus non-ruptured cases were included. Results: Out of 2733 patients with a cerebral aneurysm, 14 patients (0.5%) presented with a P1-P2 perforator aneurysm. All six patients with a ruptured aneurysm were treated by endovascular coiling, of whom one patient (16.7%) required surgical clipping of a recurrence. One out of eight (12.5%) patients with unruptured aneurysms was treated by surgical clipping. P1-P2 perforator aneurysms predominantly affected middle-aged individuals (median 59.5 years), with 10/14 (71.4%) being female. Endovascular coiling was the primary treatment modality overall, yielding favorable technical outcomes, however, it was complicated by a perforator infarct in two patients (33.3%) without new permanent morbidity or mortality secondary to treatment. Conclusions: P1-P2 perforator aneurysms are a rare subtype of intracranial aneurysm. Endovascular coiling could present an effective treatment modality; however, care should be taken for ischemic complications in the dependent perforator territory. Larger studies are required to provide more insights.

Keywords

• cerebral aneurysm
• posterior cerebral artery
• perforator artery
• endovascular coiling