Asymmetrical bilateral persistent sciatic artery complicated with right limb thrombosis: A rare CTA finding

Persistent Sciatic Artery (PSA) is a rare congenital vascular anomaly resulting from the failure of the embryonic axial artery regression. Its bilateral occurrence is even rarer, carrying a risk of serious complications such as aneurysm formation or thrombosis. This report describes the case of bilateral PSA in a 67-year-old male with a history of diabetes and hypertension who presented with symptoms of intermittent claudication in his right lower limb. Computed Tomography Angiography (CTA) confirmed the presence of bilateral PSA and revealed a striking asymmetrical presentation. The right limb showed a ``complete'' PSA with a hypoplastic superficial femoral artery (SFA) and an extensive 33-cm intraluminal thrombosis. In contrast, the left limb demonstrated an ``incomplete'' PSA with a patent, dominant SFA. This case underscores the necessity of considering uncommon vascular abnormalities, especially their asymmetrical manifestations, in the differential diagnosis of lower limb ischemia. Furthermore, it highlights the critical role of CTA as the gold standard for accurate preoperative vascular mapping, since failing to identify this anatomical asymmetry may result in iatrogenic injury and inappropriate surgical planning.