RESUMEN
Objective: This study evaluates the efficacy and safety of a new 675 nm laser source system on melasma. Background: Melasma is an acquired circumscribed hyperpigmented disorder that has a negative impact on patients' life quality. Different treatments are currently available. This study evaluates this new 675 nm laser source system, on melasma with the use of established parameters that guarantee minimum pain, the absence of side effects, and simplifying posttreatment management. Materials and methods: A total of 25 subjects (all women, 21-50 years old), with facial melasma and Fitzpatrick skin types I-III, were treated with three sessions of a new 675 nm laser system. Efficacy of treatment was evaluated using Melasma Severity Index (MSI) score before and 3 months after the last session. The appearance of side effects has also been monitored to evaluate safety. A preclinical study was executed to evaluate laser effectiveness on sheep skin. Results: All 25 subjects treated with the 675 nm laser had significant improvement in melasma according to MSI score (mean baseline MSI 26.4 ± 19.2; mean 3-month follow-up MSI 17.3 ± 15, p: 0.003). Histology in preclinical study showed selective damage of melanin-rich areas. No side effects have been observed except some minor erythematous reactions in two patients. Conclusions: Due to its high affinity with melanin, and its minimal interaction with the vascular component, novel 675 nm laser may be considered promising when treating benign pigmented lesions with a low risk of side effects and simple posttreatment management.