755-nm picosecond laser plus topical 20% azelaic acid compared to topical 20% azelaic acid alone for the treatment of melasma: a randomized, split-face and controlled trial.

PURPOSE: Melasma remains a refractory skin condition that needs to be actively explored. Azelaic acid has been used for decades as a topical agent to improve melasma through multiple mechanisms, however, there is a lack of research on its combination with laser therapy. This study evaluated the effectiveness of isolated treatment with topical 20% azelaic acid and its combination with 755-nm picosecond laser in facial melasma patients. METHODS: A randomized, evaluator-blinded, controlled study was conducted on 30 subjects with facial melasma in a single center from October 2021 to April 2022. All subjects received topical 20% azelaic acid cream (AA) for 24 weeks, and after 4 weeks, a hemiface was randomly assigned to receive 755-nm picosecond (PS) laser therapy once every 4 weeks for 3 treatments. Treatment efficacy was determined by mMASI score evaluations, dermoscopic assessment, reflectance confocal microscopy (RCM) assessments and patient's satisfaction assessments (PSA). RESULTS: Treatment with 20% azelaic acid, with or without picosecond laser therapy, significantly reduced the hemi-mMASI score (P < 0.0001) and resulted in higher patient satisfaction. Improvements in dermoscopic and RCM assessments were observed in both sides of the face over time, with no difference between the two sides. RCM exhibited better dentritic cell improvement in the combined treatment side. No patients had serious adverse effects at the end of treatment or during the follow-up period. CONCLUSION: The additional use of picosecond laser therapy showed no clinical difference except for subtle differences detected by RCM assessments.The study was registered in the Chinese Clinical Trial Registry (ChiCTR2100051294; 18 September 2021).

Laser therapy in the treatment of melasma: a systematic review and meta-analysis.

Melasma is a highly prevalent and cosmetically disfiguring pigmented skin disease. The post-treatment results are often unsatisfactory. A large number of clinical trials have tried to prove the effectiveness of the combination therapy involving laser therapy, but the results have been indeterminate. This study aimed to evaluate the effectiveness of laser treatment for melasma via a systematic review and meta-analysis. We respectively searched 4 databases and clinicaltrials.gov as of June 8, 2021. Two researchers independently searched for literature and extracted data. Study outcomes were computed by weighted mean differences (WMD). All statistical analyses were performed by the Review Manager version 5.3, STATA version 14 software at 95% confidence interval. We obtained 22 eligible studies which involved a total of 694 patients. After the heterogeneity test and sensitivity analysis, we took a subgroup meta-analysis on the before and after treatment of different laser types. We found that most lasers and laser-based combinations were associated with reduced melasma area and severity index (MASI), such as low-fluence Q-switch 1,064-nm Nd: YAG laser (QSNYL) (WMD: - 2.76; 95% CI: - 3.53 to - 1.99), fractional ablative CO2 laser (WMD: - 9.36; 95% CI: - 12.51 to - 6.21), and fractional ablative 2940-nm Er: YAG laser (WMD: - 2,72; 95% CI: - 3.94 to - 1.49). Significant decrease was seen in neither MASI score of non-ablative 1550-nm fractional laser (WMD: - 1.29; 95% CI: - 2.80 to 0.21) and picosecond laser (WMD: - 0.58; 95% CI: - 1.43 to 0.27), nor melanin index (MI) of low-fluence QSNYL treatment (WMD: 10.17; 95% CI: - 4.11 to 24.46). When using laser to treat melasma, various adverse reactions may occur, most of which will resolve quickly without subsequent treatment, such as edema, erythema, scaling, and burning sensation after treatment. However, for patients with darker skin, there are risks of postinflammatory hyperpigmentation and hypopigmentation. The laser and laser-based combination treatment for melasma could significantly reduce the MASI score, which was showed by our systematic review and meta-analysis.