Pigmentation means coloring. Skin pigmentation disorders affect the color of your skin. Skin cells give your skin color by making a substance called melanin. When these cells become damaged or unhealthy, it affects melanin production.
Melanin is produced by cells called melanocytes in a process called melanogenesis. Melanin is triggered by an enzyme called tyrosinase, which creates the color of skin, eyes, and hair shades. Melanocytes produce two types of melanin: pheomelanin (red) and eumelanin (very dark brown).
Melanin controls the amount of ultraviolet (UV) radiation from the sun that penetrates the skin by absorption.
Increased melanin production, also known as hyperpigmentation, can be:
- ♦ Melasma describes the darkening of the skin.
- ♦ Chloasma describes skin discolorations caused by hormones. These hormonal changes are usually the result of pregnancy, birth control pills or estrogen replacement therapy.
- ♦ Solar lentigines , also known as "liver spots" or "senile freckles" refers to darkened spots on the skin caused by aging and the sun. These spots are quite common in adults with a long history of unprotected sun exposure.
after exposure to UV light, there are two different mechanisms involved. Firstly, the UVA-radiation creates oxidative stress, which in turn oxidizes existing melanin and leads to rapid darkening of the melanin. Secondly, there is an increase in production of melanin (melanogenesis). Melanogenesis leads to delayed tanning and first becomes visible about 72 hours after exposure.
Melasma can fade on its own. Some people, however, have melasma for years — or even a lifetime.
Chloasma is a required hypermelanosis of sun-exposed areas occurred during pregnancy and it can affect 50-70% of pregnant women.
Commonly known as age spots or liver spots. Benign sun-induced lesion that occurs in sun-exposed areas, e.g. face, arms, hands. Not associated with any medical conditions.
Telangiectasias or angioectasias are small dilated blood vessels near the surface of the skin or mucous membranes, measuring between 0.5 and 1 millimeter in diameter. They can develop anywhere on the body but are commonly seen on the face around the nose, cheeks, and chin. They can also develop on the legs, specifically on the upper thigh, below the knee joint, and around the ankles.
The causes of telangiectasia can be divided into congenital and acquired factors.
- ♦ Naevus flammeus (port-wine stain)
- ♦ Klippel-Trenaunay syndrome
- ♦ Maffucci's syndrome (multiple endochondromas & hemangiomas)
- ♦ Hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome)
- ♦ Ataxia-telangiectasia
- ♦ Sturge-Weber syndrome, a nevus formation in the skin supplied by the trigeminal nerve and associated with facial port-wine stains, glaucoma, meningeal angiomas and mental retardation.
main reason for acquired telangiectasia is hypertension.
Telangiectasia in the legs is often related to the presence of venous hypertension within underlying varicose veins.
Sclerotherapy is the "gold standard" and is preferred over laser for eliminating telangiectasiae and smaller varicose leg veins. A sclerosant medication is injected into the diseased vein so it hardens and eventually shrinks away. Recent evidence with foam sclerotherapy shows that the foam containing the irritating sclerosant quickly appears in the patient's heart and lungs, and then in some cases travels through a patent foramen ovale to the brain. This has led to concerns about the safety of sclerotherapy for telangectasias and spider veins. In some cases stroke and transient ischemic attacks have occurred after sclerotherapy.
Varicose veins and reticular leg veins, if present, must be treated prior to any treatment of the telangiectasia. Varicose veins can be treated with foam sclerotherapy, endovenous laser treatment, radiofrequency ablation or open surgery. The biggest risk, however, seems to occur with sclerotherapy, especially in terms of systemic risk of DVT, pulmonary embolism, and stroke.
Another issue that arises with the use of sclerotherapy to treat spider veins is staining, shadowing, telangetatic matting and ulceration. In addition, incompleteness of therapy is common, requiring multiple treatment sessions.
Telangiectasias on the face are often treated with a laser. Laser therapy uses a light beam that is pulsed onto the veins in order to seal them off, causing them to dissolve. These light-based treatments require adequate heating of the veins. These treatments can result in the destruction of sweat glands, the risk increases with the number of treatments.