According to the international stage can be divided into 6 stages (C1—C6), of which C1: normal people have performance, do not need treatment; C2: in the standing position of the leg can be seen curved thickening superficial veins, higher than the skin, leg elevation or lying down can disappear, often have calf soreness, easy fatigue and other discomfort, this period can pay attention to maintenance, standing with elevated rest alternately, can prevent varicose veins aggravated; C3: varicose veins The varicose veins of the lower limbs protrude from the skin and are “earthworm-like” hovering over the lower limbs, which can be treated by elastic stockings or surgery, and is the best period for surgery; C4: excessive blood stagnation in the blood vessels, and the pressure in the veins is obviously increased, so that part of the blood components penetrate into the skin and subcutaneous tissue outside the blood vessels. The skin and subcutaneous tissues of the lower extremity, resulting in local skin redness, purple, until black (iron deposits in the blood), and the blood vessels lose elasticity and harden, itching at the skin color change, patients mostly come to the hospital in this period; C5: this period is the acute ulcer stage, the skin of the lower extremity foot boot area blackened and hardened, the skin under the action of external forces break down or even obvious bleeding, it is difficult to heal themselves, patients are mostly admitted to the hospital for emergency treatment. C6: recurrent venous ulcers without proper treatment, commonly found near the ankle joint and lower leg, commonly known as “old rotten leg”.