Efficacy and adverse reactions of fractional CO2 lasers for treating papular acne scars: a retrospective study of 35 patients.

Papular acne scars are a special type of acne scar, and the prevalence and treatment of this disease have rarely been reported in the literature; moreover, the prevalence of this disease is often neglected, and treatment is difficult. Our study revealed a high prevalence of this type of acne scar in the clinic and explored an effective and safe method. This retrospective study aimed to analyse the prevalence of papular acne scarring among patients attending our Dermatology Laser Clinic and evaluate the clinical efficacy of fractional CO2 lasers. We retrieved the data of 370 patients with acne scarring who visited our hospital between April 2021 and November 2022 and analysed the prevalence of papillary acne scarring among them. Among these patients, 35 underwent CO₂ laser treatment using an artificial grid pattern. A total of three treatments were administered, with a two-month interval between each session. Scar assessment was conducted using the Global Scar Scale (GSS) and the Acne Scar Clinical Assessment (ECCA) scale, along with physician visual evaluation and patient satisfaction surveys, both before the first treatment and one month after the final treatment. Adverse reactions were recorded during follow-up visits after each treatment. Among the 370 patients with acne scarring, 128 exhibited papular acne scarring, resulting in a prevalence rate of 34.6%. Among them, 37.5% were male and 32.6% were female. A total of 90.6% of patients had combined other types of acne scarring, while 9.4% had papular acne scarring exclusively. Following CO₂ laser grid treatment, there was a significant reduction in GSS scores and ECCA values, accompanied by a noticeable improvement in physician visual evaluation and patient satisfaction scores. Papular acne scarring has a relatively high incidence rate, and there is no significant sex difference. It often coexists with other types of acne scarring. CO₂ laser treatment using an artificial grid pattern effectively improved papular acne scarring with a good safety profile.