The document discusses venous disease and varicose veins. It begins by describing the anatomy of the venous system in the legs, including the deep and superficial venous systems that are connected by perforating veins. Valves in the veins normally prevent backflow, but when they become incompetent, venous insufficiency can occur. Common symptoms include aching, heaviness, and pain in the legs that worsens with prolonged standing or sitting. Treatment options include compression therapy and surgery to remove varicose veins or close perforating veins. Sclerotherapy can also be used to treat small varicose veins.