Hi, Thanks for writing in. It is important that you take complete treatment for DVT which is deep venous thrombosis and means a clot has formed in the deep veins of your leg. The medications and INR values are acceptable. In the leg, there are two channels of veins which help bring back deoxygenated blood to the hart. One is the deep venous system and the other being the superficial veins. When the deep veins have a clot, it is called deep venous thrombosis. This leads to shunting of blood to the superficial vines in a kind of reverse flow. These channels connecting superficial and deep veins are called perforators and they allow flow of blood from superficial to deep veins in normal circumstances. In your case, because there is a clot in the deep vein, blood around that region is showing reversal of flow with an incompetence in the perforator. This is called an incompetent perforator in the leg.