BACKGROUND To date, no studies have compared the fractional picosecond 1064-nm laser (FxPico) and fractional carbon dioxide laser (FxCO2) for the treatment of acne scars. OBJECTIVE To compare the efficacy and safety between FxPico and FxCO2 for treating facial atrophic acne scars. MATERIALS AND METHODS Twenty-five Asian patients with mild to moderate atrophic acne scars underwent single sessions of randomized split-face treatment with FxPico and FxCO2. Clinical efficacy was assessed by photographs, skin imaging analysis, and patient satisfaction. The adverse events were recorded on every visit. Skin biopsies were performed immediately and 3 months after treatment. RESULTS The physician improvement scores for skin texture and atrophy significantly increased on the FxPico sides, but no significant difference was observed between FxPico and FxCO2. Skin imaging also showed significant improvement on both sides for scar volume. Postinflammatory hyperpigmentation (PIH) was not reported on FxPico sides, whereas 6 patients (24%) experienced mild PIH on FxCO2 sides. Immediate post-FxPico skin biopsy revealed laser-induced optical breakdown with photoacoustic columns. Collagen and elastic fibers increased at 3 months after both treatments. CONCLUSION FxPico was as effective as FxCO2 in treating atrophic acne scars, correlating with evidence of tissue remodeling with more safety profiles.

Background and Objectives Treatment of melasma with lasers remains a challenge due to its limited clinical efficacy in addition to high rates of recurrence and side effects. Recently, picosecond lasers have shown favorable results in treatment of benign pigmented lesions. To compare the efficacy and safety of using a 755‐nm picosecond laser for the treatment of melasma in a split‐face manner, having one side treated with a fractionated beam (diffractive lens array [DLA] coupling) and with a full‐beam (flat optics) on the other side. Study Design/Materials and Methods Eighteen subjects presenting with mixed‐type melasma were enrolled. Each patient was randomly treated with a 755‐nm picosecond laser coupled with DLA on one side of the face and without DLA (flat optics) on the other side. The laser was delivered through an 8‐mm spot size with an average fluence of 0.4 J/cm2 at 2.5 Hz for a total of two passes without pulse overlapping. All subjects received five monthly treatments. Subjective (clinical evaluation) and objective (color readings) assessments on the degree of pigment clearance and adverse effects were obtained at 1‐, 3‐, and 6‐month after the final treatment. Results At 6 months after the last treatment, physician‐rating scores were 1.50 ± 0.76 and 1.50 ± 0.65 of the DLA and flat‐optics sides, respectively. Pigment clearance significantly improved from 1 to 6 months after the treatment on each side (P = 0.019 on DLA and P = 0.023 on flat‐optics sides). No statistically significant differences in physician‐rating scores between the two treatment techniques were observed at all follow‐up visits. Objective assessments of melasma clearance corresponded to the clinical evaluation. However, the full‐beam (flat optics) provided lower incidence of pos‐tinflammatory hyperpigmentation than the fractioned one. Conclusions A 755‐nm picosecond laser is safe and effective for the treatment of melasma in dark‐skinned individuals. The use of DLA does not provide additional benefit over the flat optics in clearing pigmentation. Lasers Surg. Med. © 2020 Wiley Periodicals LLC

Background and Objective Fractional 1064‐nm picosecond‐domain laser has recently been utilized for the treatment of atrophic acne scars and showed promising results. However, data on the safety and efficacy of this procedure in dark‐skinned patients are limited. This prospective, self‐controlled study was conducted to objectively evaluate the safety and efficacy of a 1064‐nm picosecond laser coupled with a microlens array (MLA) for the treatment of atrophic acne scars on Asian skin. Study Design/Materials and Methods Twenty‐six subjects of Fitzpatrick skin types (FSTs) III and IV with atrophic acne scars were enrolled. All subjects were treated with a 1064‐nm picosecond laser (spot size of 8 mm, fluence of 1.0 J/cm2, a repetition rate of 10 Hz) in combination with the MLA handpiece for an average of three passes, for 6 monthly sessions. Objective (measurement of scar volume using three‐dimensional (3D) photography and skin roughness analysis using ultraviolet A‐light video camera) and subjective (clinical evaluation by two blinded dermatologists) assessments were obtained at baseline and at 1, 3, and 6 months after the final treatment. Results Statistically significant reduction of the scar volume from baseline at 1, 3, and 6 months after the final treatment were observed by 3D photography and ultraviolet A‐light video camera. At the 6‐month follow‐up, 50% (13 of 26) of the subjects were rated as having at least 50% improvement of the scars. The rate of improvement significantly increased from the 1‐month follow‐up to the 6‐month follow‐up (P = 0.013). Similarly, at the 6‐month follow‐up, the scar volume (P = 0.024) and skin roughness (P = 0.001) also significantly improved, in comparison with the baseline. Mild postinflammatory hyperpigmentation (PIH) was observed to develop in approximately 18% of all the treatment sessions. All cases of PIH were temporary and resolved within 4 weeks on average. Conclusions The 1064‐nm picosecond laser with MLA is a safe therapeutic alternative for the treatment of atrophic acne scars in dark‐skinned individuals. Lasers Surg. Med. © 2020 Wiley Periodicals LLC