Melasma, also known as liver spots, is a common hyperpigmented skin disease occurring on the face, which can develop in both men and women, but is mostly seen in middle-aged women. The lesions are pale brown, coffee-colored or dark black patches with different sizes and irregular shapes. The surface is smooth without scaling and inflammation, and there are no self-perceived symptoms. They often appear symmetrically on both cheeks in a butterfly shape, and can also be seen on cheekbones, forehead, eyebrows and around the mouth, with individual patients spreading to the whole face. Some patients have increased skin pigmentation in the areola, external genitalia, armpits and groin. The etiology and pathogenesis of melasma: 1, physiological reaction: in pregnant women, the disease gradually disappears after delivery in the third to fifth month of pregnancy, and can still develop after re-pregnancy, which may be related to the imbalance of progesterone and estrogen in the body. 2, symptomatic reactions: seen in patients with dysmenorrhea, menstrual disorders, chronic pelvic inflammatory disease, liver cirrhosis, chronic adrenocortical insufficiency, chronic ethanol poisoning, tuberculosis, chronic bronchitis in the elderly, bronchial dilatation, tumors, etc. 3, drug factors: oral contraceptives cause the most, generally occurring after 1-20 months of oral intake, accounting for about 20%. It has been proved that it is due to the combined effect of estrogen and progestin. 4, cosmetic factors: with the widespread use of cosmetics, cosmetics caused by pigmentation is increasing, cosmetic dermatitis often left pigmentation after subsiding. 5, nutritional factors: some people due to the lack of vitamin A, vitamin C, vitamin E, niacin, zinc or certain amino acids, can also make the disease occur or develop, after giving supplementation can get significantly better. 6, other factors: such as thermal stimulation. External medication, mental depression, frequent staying up late, excessive fatigue, etc. can also be contributing factors. Treatment of melasma: 1, systemic treatment: vitamin C orally, 1~3g per day, or 2g by injection. Vitamin C can reduce the darker oxidized pigment to lighter reduced pigment, and reduce dopaquinone to dopa, so as to inhibit the formation of melanin. However, it can only control and cannot eradicate melasma. 2.Laser treatment: Treatment with Q-switched pulsed gemstone laser followed by pulsed laser to destroy melanocytes and reduce epidermal melanin, thus achieving better results in treating dermal melasma. The principle of laser melasma removal is to use high-intensity light beam with specific wavelength to be absorbed by pigments or tissues in the skin. The laser breaks down the pigment substances deposited in the skin to make them decompose in nano-level time, and promotes the circulation of the basal skin to reduce the thermal damage effect of the treatment on the surrounding skin. As the pigment particles are gradually absorbed by the body, the color fades and finally disappears completely after several treatments. The effect of laser melasma removal is safe, less painful without leaving scars and has a rejuvenating effect. 3.Intense pulsed light treatment: Intense pulsed light uses broad spectrum to act directly on the skin surface to remove facial melasma and stimulate skin collagen growth. After skin rejuvenation treatment, facial chloasma quickly fades away. The treatment process is easy and comfortable, and a thorough skin care is done while removing the spots. As a kind of advanced high-tech beauty program, color light skin rejuvenation uses a specific broad-spectrum color light, which is directly irradiated on the surface of the skin. It can penetrate to the deeper layers of the skin, selectively act on the subcutaneous pigments or blood vessels, decompose pigmentation, close the abnormal red blood vessels, and lift all kinds of blemishes on your skin, while photons can also stimulate subcutaneous collagen growth, making your skin fresh, young, healthy and shiny. Intense pulsed light treatment is the new method to get rid of melasma at present.