Case Study: Cystic Adventitial Disease of the Popliteal Artery

Introduction —Adventitial cystic disease is an unusual cause of lower-extremity ischemia. It affects large arteries, typically where the artery is near a joint space, and the popliteal artery is most commonly involved. Methods —A 60-year-old man with venous insufficiency and prior deep vein thrombosis was referred for a lower-extremity venous evaluation. He had chronic degenerative joint disease, with bilateral knee osteoarthritis, but a history of exertional right calf pain was elicited. His right femoral and popliteal pulses were normal, but the posterior tibial pulse was diminished and the dorsal pedal artery pulse was absent. A lower-extremity duplex ultrasound examination was performed, including conventional and panoramic B-mode imaging, color Doppler and power Doppler imaging, and pulsed flow assessment. Results —Chronic deep and superficial venous thrombosis was identified in the right lower extremity. During the examination, the right popliteal artery was noted to be abnormal. Imaging showed the flow lumen in the popliteal artery to be visibly narrowed by more than 50%. Peak systolic velocities (PSV) in the proximal popliteal artery were 82 cm/sec, with a normal triphasic waveform, but the PSV increased to 221 cm/sec through the stenotic segment. The luminal narrowing was limited to an approximately 3 cm segment of the popliteal artery. There was no visible plaque or evidence of vascular calcification. The lumen appeared compressed by hypoechoic, septated cystic material. There was no flow within the well-visualized cystic structure. The findings were subsequently correlated with arteriography. Adventitial cystic disease of the popliteal artery was diagnosed. The patient underwent successful right popliteal artery cystectomy. Intra-operative and post-operative duplex evaluations demonstrated normal findings. Conclusion —Cystic adventitial disease is a rare disorder that can compromise arterial perfusion to the leg and it is one nonatherosclerotic cause of intermittent claudication. In some cases, the popliteal artery may occlude. Incidental arterial disease may be encountered frequently with lower extremity venous duplex scanning. With a careful examination by a thorough technologist, rare and interesting pathology, such as cystic adventitial disease, is possible.