Procedure: 6 to 9 ultraviolet B treatments
Treatments with ultraviolet B with gradually progressive doses
Other Name: phototherapy
Procedure: Skin biopsies
4 mm punch biopsies of the skin
Other Name: Skin biopsy, skin sample
Patients with vitiligo received 6-9 ultraviolet B treatments, 2 to 3 times weekly. Minimal erythema dose (MED) testing was done at baseline and after all treatments; the percent change in MED was analysed as a measure of photoadaptation. The percent decrease in cyclobutane pyrimidine dimers (CPDs) over 24 hours after a single exposure of 1 MED was analysed on vitiliginous and normal skin.