Comparison of electrodesiccation and potassium-titanyl-phosphate laser for treatment of dermatosis papulosa nigra

BACKGROUND There is a lack of randomized split-face studies investigating treatments for dermatosis papulosa nigra (DPN) in dark skin. OBJECTIVE To compare the efficacy, safety, and tolerability of potassium-titanyl-phosphate (KTP) laser with efficacy, safety, and tolerability of electrodesiccation in the treatment of DPN in subjects with Fitzpatrick skin phototypes IV to VI. METHODS Fourteen subjects with Fitzpatrick skin phototypes IV to VI were randomized to receive two KTP laser treatments 4 weeks apart to half of the face. The contralateral half received two electrodesiccation treatments 4 weeks apart. Response was evaluated by photography reviewed by blinded dermatologists at 4 weeks after the second treatment. A treatment quality questionnaire about side effects and cosmetic outcome was also administered. RESULTS Difference in improvement of DPN between the KTP side and the electrodesiccation side per each rater (p=.99, p=.54) and per raters combined (p=.50) did not reach statistical significance. There was no treatment difference for subjective effectiveness (p=.06) or subjective confidence improvement (p=.99), although there was a significant treatment difference for subjective discomfort (p=.002) in favor of KTP. Both treatments were well tolerated without significant adverse effects. CONCLUSIONS Although treatment of DPN with KTP laser and electrodesiccation are comparable in efficacy, KTP laser is preferable for patient comfort. The authors have indicated no significant interest with commercial supporters.