Patients with chronic lower limb edema commonly suffered from extremities edema, pain, varicosities, venous stasis changes, and deep venous thrombosis. A common challenge for primary care physicians is to determine the cause and find an effective treatment for leg edema of unclear etiology. The aims of this project are to determine the cause of patients with chronic lower limb edema with conventional digital venography, the clinical value of role of 3D rotational venography or combined multidetector (MD)CT angiography and iliac venography using direct iliac venography for contrast administration via bilateral femoral catheterization (MDCT angiography/venography) with volume-rendering images supplementary to 2D digital venography in evaluation of patients with chronic lower limb edema.