Clinical efficacy of large-spot and low-energy Q switched Nd:YAG laser in the treatment of melasma

Objective To evaluate the effect of large-spot and low-energy Q switched Nd:YAG laser on melasma,and to observe the changes of melasma lesions with confocal laser scanning microscopy (CLSM) before and after the laser treatment.Methods Totally,45 patients aged from 24 to 48 years and diagnosed with facial melasma were included in this study,and treated with large-spot and low-energy Q switched Nd:YAG once a week for 10 or more sessions.CLSM was used to estimate the melanin content in melasma lesions before each irradiation and after the last irradiation.Results Among the 45 patients,8 ( 17.78％ ) were nearly cured,25 (55.56％) markedly improved,11 (24.44％) improved,and only 1 (2.22％) unimproved after the laser irradiation.The total response rate was 73.33％.As CLSM showed,there was an increment in melanin granules in melasma lesions compared with the normal skin surrounding melasma lesions,but a reduction in melanin granules was induced by the laser treatment in melasma lesions.Conclusions Large-spot and lowenergy Q switched Nd∶YAG laser is substantially effective and highly safe for the treatment of melasma,and CLSM can be used to evaluate the therapeutic effect of laser on melasma. Key words: Confocal laser scanning microscopy;  Melasma;  Laser