[Extra-popliteal localizations of adventitial cysts. Review of the literature].

Cystic adventitial disease is an uncommon vascular anomaly first described in 1947 in the external iliac artery. The preferential localization is the popliteal artery although other arteries and veins may also be involved though not always recognized. There have been 45 extra-popliteal localizations of adventitial cysts reported in the literature. Thirty cases involved an artery an 15 a vein. The iliofemoral axis, with 33 reported cases, is the preferential localization of these extra-popliteal adventitial cysts (including 22 arteries and 11 veins). All the other cases also involved a vessel near an articulation (knee, ankle, elbow, wrist). Despite a preferential popliteal arterial localization only one case involved the popliteal vein. The diagnosis is rarely made before surgery, probably because of the nonspecific clinical presentation. Ultrasonography should allow better recognition of these adventitial cysts, eliminating an aneurysm or a synovial cyst, and evidencing the localization of the cyst within the vessel wall.