Melasma is an acquired pigmentation disorder with complex pathogenesis. In addition to the dysfunction of melanocytes, the imbalance of the microenvironment, particularly the multicellular interactions among keratinocytes, fibroblasts, vascular endothelial cells, mast cells, and sebocytes, also contributes to the progression of melasma. This review summarizes relevant research progress on melanocytes and their microenvironment in the pathogenesis of melasma, as well as advances in the treatment of melasma.

Objective To observe and analyze the clinical efficacy and safety of carvedilol combined with dual-wavelength pulsed dye laser in the treatment of rosacea.Methods A retrospective analysis was per-formed on 50 patients with rosacea mainly characterized by flushing,erythema,and telangiectasia who were treated with dual-wavelength pulsed dye laser in the Department of Dermatology of this hospital from October 2023 to October 2024.They were divided into the observation group and the control group according to differ-ent treatment methods,with 25 cases in each group.The control group received dual-wavelength pulsed dye la-ser treatment,while the observation group received carvedilol combined with dual-wavelength pulsed dye laser treatment.The clinical erythema assessment(CEA)scale and physician global assessment(PGA)were used to evaluate the efficacy of the two groups,and the occurrence of adverse reactions was recorded.Results After treatment,the CEA scores of both groups were lower than those before treatment.The CEA score of the ob-servation group was lower than that of the control group,and the PGA score was higher than that of the con-trol group,with statistically significant differences(P<0.05).No singnifcant adverse reactions occurred in ei-ther group.Conclusion Carvedilol combined with dual-wavelength pulsed dye laser is more effective than sin-gle dual-wavelength pulsed dye laser in the treatment of rosacea,and the treatment method is safe.

Melasma is an acquired pigmentation disorder with complex pathogenesis. In addition to the dysfunction of melanocytes, the imbalance of the microenvironment, particularly the multicellular interactions among keratinocytes, fibroblasts, vascular endothelial cells, mast cells, and sebocytes, also contributes to the progression of melasma. This review summarizes relevant research progress on melanocytes and their microenvironment in the pathogenesis of melasma, as well as advances in the treatment of melasma.