Efficacy and Safety of Low Fluence Nd:YAG Laser Treatment in Melasma: A Meta-Analysis and Systematic Review

Low-fluence, multisession therapy of Nd:YAG laser has been widely used for treating melasma.To evaluate the efficacy and safety of low-fluence Nd:YAG laser toning for melasma using a systematic review and meta-analysis.The PubMed, Web of Science, Embase, and Cochrane Library databases were searched till December 2020. A total of 50 studies (1,772 patients) and 66 studies were selected for the evaluation of the efficacy and complications, retrospectively.The mean Melasma Area and Severity Index/modified Melasma Area and Severity Index scores for laser toning as monotherapy at <4, 4 to <8, 8 to <12, 12 to <24, and ≥24 weeks after treatment compared with that at pretreatment were -0.51, -0.91, -0.97, -0.92, 0.01 SD, whereas those as combination therapy were -1.64, -1.26, -0.94, not available, -1.45 SD, respectively. An increase in light value and a decrease in relative lightness index have remained up to 8 weeks after laser toning. Complications including hypopigmentation/leukoderma, postinflammatory hyperpigmentation, and recurrence were noted. The incidence of hypopigmentation/leukoderma correlated with the number of laser sessions (p = .036).Low-fluence Nd:YAG laser toning as combination therapy has shown better efficacy than monotherapy and the efficacy seems to diminish with time. This study suggests the positive correlation of hypopigmentation/leukoderma with the number of laser sessions.