Prospective Evaluation of a Fractional 675-nm Nonablative Laser for Atrophic Acne Scars in Fitzpatrick Skin Types III–IV

Abstract

Background: Energy-based treatments for atrophic acne scars (AAS) in darker skin phototypes must balance efficacy with pigmentary safety. While the nonablative 675-nm laser has shown promise with minimal risk of adverse effects, prospective data in Asian populations remain limited. This study evaluated the efficacy, tolerability, and safety of a 675-nm laser for AAS in Fitzpatrick skin types (FSTs) III–IV. Methods: Sixteen adults with AAS underwent 3 monthly sessions using sequential Moveo (low-fluence scanning) and Standard (fractional stamping) modes. Outcomes were assessed at baseline and at 1, 3, and 6 months after the final session, including Goodman and Baron quantitative scores (GBQGASGS), Antera® 3D imaging device, patient satisfaction, procedural pain, and adverse events. Results: GBQGASGS improved by 14.5% at 6 months after the final treatment (19.81 ± 7.31 to 16.94 ± 7.18; p = 0.001), with a 9.7% reduction evident 1 month after the second session (p = 0.017). Antera® 3D analysis demonstrated improvements in skin texture (12.91 ± 4.25 to 11.38 ± 3.97; p = 0.002) and scar volume (2.54 ± 1.33 to 2.04 ± 1.26; p = 0.001). At 6 months, blinded evaluators reported ≥ 25% improvement in 50% of subjects, while 69% of patients reported ≥ 25% improvement. Adverse events were of low incidence and transient in nature, and no serious complications occurred. Conclusions: The 675-nm laser demonstrated significant and sustained improvements in acne scar metrics in Asian patients with FST III–IV, supporting its role as a pigment-safe, nonablative option for atrophic acne scars in skin of color. Trial Registration: Thai Clinical Trials Registry: TCTR20250218009.