Effectiveness and safety of 2940-nm multifractional Er: YAG laser on acne scars.

Erbium: Yttrium-aluminum-garnet laser (Er: YAG) treatment has been used in resurfacing the acne scars for a long time; however, we could not find any study reporting the recovery rates after each session of the treatment. In this study, we aimed to report the improvement rates after each session. We retrospectively analyzed the data of 35 patients with acne scars treated with fractional ablative Er: YAG laser. The patients received one to four sessions of treatment with 4-week intervals and improvement rates were recorded after each session. Data are available on request from the authors. The improvement rate of the lesions varied between 1% and 25% in 34 patients at the end of the first session, while in one patient, the improvement rate was detected as 26% to 50%. At the end of the fourth session, the rate of improvement was 26% to 50% in 14 out of 24 patients and 51% to 75% in 10 patients. None of the patients showed a 76% to 100% improvement at the end of the fourth session, whereas 48.6% of the patients were satisfied with the treatment. In patients with a high expectation of an excellent improvement, a higher number of sessions of the laser treatment and/or combination treatments with different treatment methods should be planned.