title: Efficacy and safety of Q-switched 1,064-nm neodymium-doped yttrium aluminum garnet laser treatment of melasma.
abstract: BACKGROUND
  Melasma is a common pigmentary disorder that affects all skin types but is seen more in individuals with Fitzpatrick skin type IV to VI. Safe and effective treatment options for melasma need to be explored. Already proven effective for the treatment of pigmentary disorders, lasers have been used to treat melasma in recent years.
  
  
  OBJECTIVE
  To evaluate the efficacy and safety profile of a 1,064-nm Q-switched neodymium-doped yttrium aluminum garnet (QS Nd:YAG) laser in the treatment of melasma.
  
  
  METHODS
  Fifty patients were recruited for this study (47 female; 3 male). All were treated using the 1,064-nm QS Nd:YAG laser at low energy levels weekly for nine sessions. Follow-up was done 3 months after the final laser session, and recurrence rates were evaluated. Digital photographs were taken and the melanin index (MI) measured before each treatment visit and after the final treatment. Melasma Area and Severity Index (MASI) scores were evaluated for all of the patients. Patients were required to evaluate their satisfaction at the end of the nine treatments. We also used a confocal laser scanning microscope (CLSM) for several patients to investigate pathologic changes at baseline, after the treatments, and at the time of recurrence. Statistical analysis was performed to evaluate clinical response and factors related to the therapeutic outcome.
  
  
  RESULTS
  Mean MI decreased 35.8%, from 70.0 at baseline to 44.9 after the treatment (p<.001). Mean MASI scores decreased 61.3% after therapy (from 10.6-4.1, p<.001); 70% of patients had more than a 50% decrease in their MASI values, and 10% had 100% clearance. Recurrence rate at the 3-month follow-up was 64%. CLSM findings indicated less melanin in the treated regions, although it increased at recurrence. Multiple linear regression indicated that the therapeutic outcome depended on disease severity at baseline (p=.001, R=0.494). Minimal adverse events were observed during the study.
  
  
  CONCLUSIONS
  The 1,064-nm QS Nd:YAG laser is an effective and safe treatment for melasma, although recurrence rates remain high, and further adjunctive therapy needs to be explored to prevent this recurrence.
authors: Dermatology Department, Xiangtan Central Hospital, Hunan, China.
authors: Xi
authors: X
authors: Zhou
authors: Michael H
authors: MH
authors: Gold
authors: Zhong
authors: Z
authors: Lu
authors: Ying
authors: Y
authors: Li