Two cases of symptomatic adventitial cystic disease involving the popliteal artery and femoral vein.

Adventitial cystic disease is a rare condition involving mucinous cysts within the adventitial layer of arteries or veins. We report two distinct cases: one in the popliteal artery presenting with intermittent claudication and another in the femoral vein presenting with limb swelling and pain. The diagnosis was established based on characteristic imaging findings, and both lesions were completely excised without recurrence. The arterial cyst contained clear gelatinous fluid, and the venous cyst contained hemorrhagic material, possibly related to anticoagulant use. Adventitial cystic disease should be considered in the differential diagnosis of peripheral vascular conditions owing to its variable presentation.