Ruptured Aneurysm in Complete Duplication of the Posterior Cerebral Artery: Successful Treatment With Endovascular Coiling

The fetal posterior cerebral artery (FPCA) variant is rare, and among these, complete duplication of the posterior cerebral artery (PCA) represents the rarest form. In this case report, we describe a 39-year-old woman with an aneurysm arising from complete duplication of the PCA. The aneurysm was successfully occluded while preserving FPCA patency using endovascular coiling with the double-microcatheter technique, and no recurrence of the aneurysm was observed on brain magnetic resonance angiography (MRA) at six-month follow-up. To the best of our knowledge, this is the first reported case of an aneurysm arising from complete duplication of the PCA that was successfully treated by endovascular coiling. We highlight the anatomical characteristics of complete duplication of the PCA, the utility of multimodal imaging in identifying FPCA variant, and the need to preserve the FPCA during aneurysm treatment to prevent PCA territory infarction.