Comparing fractional CO₂ laser and needling-based modalities in facial acne scar treatment: a comprehensive systematic review and meta-analysis.

Facial acne scarring is a widely prevalent dermatological disease manifested as a permanent aftereffect of acne vulgaris. While fractional CO₂ laser and needling procedures are essential to treating atrophic acne scars, comparative and safety data remains limited. This systematic review and meta-analysis directly compares their efficacy and safety. According to PRISMA guidelines, PubMed, Cochrane, Google Scholar, and ClinicalTrials.gov were systematically searched. Only studies comparing fractional CO₂ laser with needling-based monotherapy treating facial atrophic acne scars in adults were included. A random-effects model was employed for meta-analysis using Review Manager (RevMan) to compare efficacy and safety outcomes. A total of 17 studies were included in the meta-analysis. For primary efficacy outcomes, the results were non-significant for mean scar score reduction (SMD: -1.08, 95% CI: [-2.48, 0.32], I² = 97%) or mean quantitative scar reduction (SMD: 0.12, 95% CI: [-0.80, 1.04], I² = 92%), with significant heterogeneity. However, categorical treatment success was significantly high for CO₂ laser (RR: 1.10, 95% CI: [1.01, 1.20], I² = 0%). For safety outcomes, fractional CO₂ laser showed significantly high risk of post-inflammatory hyperpigmentation (PIH) as compared to standard microneedling (RR: 3.04, 95% CI: [1.49, 6.21], I² = 3%), but showed significantly low pain scores as compared to RF microneedling (SMD: -0.74, 95% CI: [-1.27, -0.21], I² = 0%). No significant differences were found for erythema, crusting/scabbing, or edema. Both fractional CO₂ laser and microneedling procedures show comparable efficacy in treating atrophic acne scars, however, patient variables such as skin type, scar type, and possible complications should be taken into consideration. Moreover, further tailored therapies are crucial to treating acne scars with low risk for complications.