Skin Pigmentation Disorders: Hyperpigmentation & Hypopigmentation
The two most common skin disorders are hyperpigmentation (skin darkening) and hypopigmentation (skin lightening. The quantity and activity of melanocytes is the major determinant of these disorders.
United States Simi Paknikar Skin Pigmentation Disorders Pigmentation Disorders Skin Pigmentation Functional Characterization
Source: medindia.net