Comparison of multiple 1565 nm fractional Er: glass laser and single fractional CO2 laser in the treatment of atrophic acne scars: a prospective, randomized split-face study.

Both ablative fractional laser (AFL) and non-ablative fractional laser (NAFL) are gaining popularity in the treatment of atrophic acne scars. However, single NAFL may not be as effective as single AFL in clinical practice. This split-face and evaluator-blind study compared the efficacy and safety of multiple consecutive NAFL (1565 nm Er: glass laser) and a single AFL (10600 nm CO₂ laser) in the treatment of facial atrophic acne scars. 13 subjects with V, U and M-shape atrophic scars were treated with either NAFL group (once a month for 3 consecutive sessions of 1565 nm Er: glass laser) or AFL group (a single session of fractional CO₂ laser). We found that both AFL group and NAFL group showed decreased 4-point scale and ECCA scores for respective V, U, M types, but there was no statistically difference between the two groups. NAFL group showed lower pain score, less oozing and crusting, and shorter duration of the adverse effects as well. The average satisfaction score was higher in NAFL group, although there was no statistically significance. In conclusion, consecutive triple NAFL treatment could approach a single AFL treatment for atrophic acne scars, while NAFL treatment causes less pain and fewer adverse events.