Comparative efficacy and safety of single-pulse mode vs. six-pulse mode 1,064 nm Q-switched neodymium-doped yttrium aluminum garnet laser for treating facial pigmentary disorders in Republic of Korea: retrospective clinical study

Background: Facial pigmentary disorders, including melasma, post-inflammatory hyperpigmentation, and solar lentigines, present significant therapeutic challenges in dermatology.The 1,064 nm Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser has been established as an effective treatment modality for these conditions.This study aimed to compare the clinical efficacy and safety profile of singlepulse mode vs. six-pulse mode 1,064 nm Q-switched Nd:YAG laser treatment for facial pigmentary disorders. Methods:The retrospective analysis included 40 patients with facial pigmentary disorders, who were divided equally into two groups: one treated with the single-pulse mode (n = 20) and the other with the six-pulse mode (n = 20).Outcomes were evaluated using medical records and pre-and post-treatment photographs. Results:The six-pulse mode group demonstrated significantly superior improvement in pigmentation compared to the single-pulse mode group (mean score, 4.05 vs. 3.3; p < 0.05).The Mann-Whitney U test yielded a U statistic of 92.5 with statistical significance (p < 0.05).Both treatment modalities exhibited comparable safety profiles, with only mild, transient erythema and edema that resolved within 24-48 hours.No significant adverse effects were observed in either group. Conclusion:The six-pulse mode 1,064 nm Q-switched Nd:YAG laser demonstrated superior therapeutic efficacy compared to the single-pulse mode for treating facial pigmentary disorders while maintaining an equivalent safety profile.These findings support the clinical application of multi-pulse technology, particularly for patients with refractory pigmentary conditions.