Abstract
Cystic adventitial disease (CAD) is a rare cause of claudication in which a mucinous cyst forms within the adventitial layer of a blood vessel, most commonly the popliteal artery, resulting in luminal narrowing. This paper presents a case of a man in his mid-50s with unilateral lower limb popliteal artery CAD, which was not initially identified on either duplex ultrasonography or CT angiography. He was successfully treated with surgical resection of the affected segment of the popliteal artery and autologous vein grafting.