A Report of Two Cases of Adventitial Cystic Disease of the Popliteal Artery.

Two patients were admitted to our department because of recent aggravation of claudication in the leg, which was exacerbated by walking. They were diagnosed as having a Baker cyst or acute thrombosis in the popliteal fossa at another hospital. There was no evidence of ischemia, and the ankle brachial index was normal. Computed tomography and magnetic resonance imaging were performed, revealing a cystic mass of the popliteal artery (PA). Intraoperatively, the cystic lesion was found within the adventitia of the PA; based on the biopsy findings, both patients were diagnosed as having adventitial cystic disease of the PA.