Adventitial cystic disease of the popliteal artery as a cause of intermittent claudication: not your usual suspect. Report of one case Adventitial cystic disease of the popliteal artery is a rare condition of uncertain etiology, which presents as intermittent claudication of the lower extremity in middle-age patients. We report a 44-year-old man presenting with intermittent claudication of his left leg. MR angiography showed cystic parietal lesions that caused compression with partial occlusion of the left popliteal artery. Surgical resection of the affected segment was performed, with venous graft interposition. The histopathological analysis of the surgical specimen was consistent with cystic adventitial disease.