๐ ็ธฝ็ฎ้ ๏ฝ ๐ ่ฑๆๅๆ๏ผๆฌ็ฏ๏ผ ๏ฝ ๐ ๅฎๆด็ฟป่ญฏ ๏ฝ โญ ็ฒพ่ฏ็ญ่จ
Blue hypermelanosis
Blue hypermelanosis
The excess melanin is present in the dermis, which lends a blue color to the lesion (Tyndall effect), and the pigmentation is not accentuated on Woodโs lamp examination.
The dermal pigmentation is due to pigmentary incontinence (PI) caused by basal cell layer damage, and the melanin may be present either free in the dermis or within melanophages. Other causes include ectopic dermal melanocytes and exogenous pigment deposition.
Mixed hypermelanosis is due to increased pigment present in both epidermis and dermis.