Endovascular Treatment of an Anatomically Complex Iliac Lesion and a Review of Variant Iliac Venous Anatomy.

The diagnosis and treatment of pelvic venous disease is complicated by a number of potential venous anatomic variants. Stent-assisted recanalization of a chronically occluded left external iliac vein draining directly into the inferior vena cava, with absence of the left common iliac vein, is described here. Variant iliac venous anatomy is reviewed in 3 categories: additional iliac vessels, absence/shortening of iliac vessels, and deviations in the drainage pattern of iliac vessels. Additionally, variations of the ascending lumbar and iliolumbar veins, the identification of which can aid in the treatment of pelvic venous disease, are described.