PIGMENTARY CHANGES IN AGED AND PHOTOAGED SKIN

Progress has been made in defining the structural and functional alter ations that occur in skin with age. Changes caused solely by longevity have been delineated from changes due to long-term sun exposure, Unev en pigmentation is 1 of the major changes in the gross morphologic cha racteristics of the aging skin and is much more marked in sun-exposed areas. In the epidermis, melanin pigments are good indicators of photo aging. Ultraviolet radiation plays a major role in the induction of me lanocyte aging and may severely damage the melanocyte system of the sk in, resulting in both hypermelanotic and hypomelanotic lesions.