When dark pigments seem to appear on the skin, it is known as hyperpigmentation. This is because, the skin starts producing more melanin, which is a pigment responsible to give skin its color.
Hyperpigmentation can also be termed as dyschromia or increased pigmentation. There are certain areas of skin wherein melanin is produced in excess, resulting in formation of deposits, which result in producing skin patches that are darker than the skin in the surrounding area. The most commonly affected areas include those parts of body that are exposed to sun such as hands, arms and face.
Excessive sun exposure leads to formation of sunspots or freckles. When it comes to mountain areas of the United States of America or Australia the smallest of exposure or sun rays that can come through your window, may affect you. The sun is very strong in the above mentioned areas and slightest of sun exposure may result in freckles. The main components that characterize Melasma are the type of skin pigmentation and its distribution on the face. At times, your Plastic surgeon may recommend removing a small skin sample (numbed by local anesthetic) for assessment under the microscope (skin biopsy) so that other diagnoses may be ruled out.