Combining Low Power Fractional CO With QS-NdYAG Toning in the Treatment of Melasma Reduces the Incidence of Punctate Leukoderma

Background And Objectives: Q-switched Nd:YAG (QS-Nd:YAG) toning (low fluence, large spot size, and high frequency) has been used successfully for the treatment of melasma, especially in dark skin phototypes. Punctate leukoderma was found to be a frequent complication that reduced the safety of this procedure. Combining low power fractional CO laser, which is another effective melasma laser therapy, might improve the efficacy and safety of this procedure. The aim of this study was to evaluate  the effect of combining low power fractional CO laser with QS-Nd:YAG toning in the treatment of melasma.

Study Design/materials And Methods: A randomized comparative split-face study included a total of 30 patients with bilateral, symmetrical melasma. All patients received QS-Nd:YAG toning on one randomly selected side of the face, while the other side randomly received either low power fractional CO alone (group A) or combined QS-Nd:YAG toning with low power fractional CO (group B). QS-Nd:YAG toning sessions were scheduled every two weeks for nine consecutive sessions, and low power fractional CO sessions were received every 4 weeks for three consecutive sessions. The assessment was done using the modified melasma area and severity index (mMASI) score, spectrophotometry (melanin index [MI] and erythema index [EI]), photography, blinded physician assessment, and patient satisfaction (at baseline, 1 week and 8-12 weeks after the last treatment sessions).

Results: A significant reduction in the mMASI score and MI was obtained with all treatment regimens. On comparing different modalities, group A reduction in mMASI and MI was significantly greater on the side receiving QS-ND:YAG toning (64.03% and 8.27%, respectively), than the side receiving low power fractional CO laser alone (36.02%. 2.64%, respectively). On the other hand, reduction of mMASI score and MI showed no statistical significance between the side receiving QS-Nd:YAG toning alone and the combined modality. Punctate leukoderma occurred in four cases (13%) on the side receiving QS-Nd:YAG toning.

Conclusion: QS-Nd:YAG toning is significantly more effective than low power fractional CO in the treatment of melasma when used separately. Although combining low power fractional CO with QS-Nd:YAG toning does not increase its efficacy, it minimizes the incidence of the undesirable punctate leukoderma complication and achieves lower recurrence. This combination can thus be recommended as a safe and effective measure for the treatment of melasma. © 2021 Wiley Periodicals LLC.