Low-power fractional CO₂ laser versus low-fluence Q-switch 1,064 nm Nd:YAG laser for treatment of melasma: a randomized, controlled, split-face study.

Background: Various laser treatments are currently available for melasma but their use remains challenging because of potential side effects.

Objective: The aim of this randomized controlled study was to compare the efficacy and safety of low-fluence Q-switch 1,064 nm Nd:YAG and low-power fractional CO2 laser using a split-face design.

Methods: A total of 40 female patients with symmetric melasma were enrolled to the study and each side of their face was randomly allocated to either low-fluence Q-switch 1,064 nm Nd:YAG or low-power fractional CO2 laser. They were treated every 3 weeks for five consecutive sessions and followed for 2 months after the last treatment session. Response to treatment was assessed using the Melanin Index (MI) score, modified Melasma Area and Severity Index (mMASI) score, and a subjective self-assessment method.

Results: At the 2-month follow-up visit, both sides of the face had statistically significant reductions in the MI and mMASI scores compared with the first visit (p < 0.001). The differences between the mean MI and mMASI scores at baseline and at 2-month follow-up were compared between the two treatments and results showed that the reduction of MI and mMASI score in the fractional CO2 laser-treated side was significantly more than on the Q-switch 1,064 nm Nd:YAG laser-treated side (p < 0.001). There were no significant adverse effects with either of the laser treatments.

Conclusions: The present study shows that low-power fractional CO2 laser is safe and effective and can be considered as a valuable approach in the treatment of melasma.