Chronic exposure to ultraviolet light can result in skin thickening as well as elastic destruction of the skin. At least in one instance, the occupational exposure to the UVA light of the sun (UVB is blocked by many car windows) resulted in skin destruction on one side of the face. Microscopically,<unk><unk>  displays multiple dilated follicular cysts/milia and open comedones with severe solar elastosis in the background dermis.
Favre–Racouchot syndrome
Gougerot–Blum syndrome
Juberg-Hayward syndrome
Jeavons syndrome
McGillivray syndrome
Van Wyk and Grumbach syndrome
Bowen–Conradi syndrome
Bogart–Bacall syndrome