The venous network in the lower extremities commonly affected by CVI is divided into 3 systems. The first is superficial veins, which include the lesser and greater saphenous veins and their tributaries, as depicted in the 1st image below. The second is deep veins, which include the anterior tibial, posterior tibial, peroneal, popliteal, deep femoral, superficial femoral, and iliac veins. The third is perforating or communicating veins, as depicted in the 2nd and 3rd image below.

In patients with symptomatic greater saphenous varicosities, the presence of an occluded deep system must be ruled out. Deep occlusion is an absolute contraindication to vein ligation. Obtaining venographic studies of the deep venous system prior to superficial vein ligation is imperative.

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