Efficacy and Safety of Er:Glass versus CO2 Lasers in the Treatment of Atrophic Acne Scars: A Systematic Review and Meta-Analysis.

BACKGROUND

Fractional laser therapy is a cornerstone for atrophic acne scar treatment. While both ablative fractional CO2 and non-ablative fractional Er:Glass lasers are widely used, comprehensive comparative data on their efficacy, patient satisfaction, and complication profiles remain limited. This meta-analysis aimed to quantitatively compare these outcomes.

METHODS

A systematic literature search was performed in PubMed, Web of Science, and Cochrane Library up to March 5, 2025. Prospective randomized trials directly comparing Er:Glass and CO2 lasers for atrophic acne scars were included. Outcomes were effective rate (>50% improvement), patient satisfaction rate, pain (VAS), post-inflammatory hyperpigmentation (PIH) rate, duration of crusting and duration of erythema. Data were pooled using meta-analysis in R (meta package).

RESULTS

Four studies (98 participants) were included. Pooled analysis showed no significant difference in effective rate (OR = 0.43, 95% CI 0.03-5.98) or patient satisfaction rate (OR = 0.70, 95% CI 0.08-6.25) between lasers. PIH rates were similar (OR = 0.50, 95% CI 0.17-1.45). Er:Glass was associated with significantly less pain (MD = -1.70, 95% CI -2.13 to -1.28), shorter duration of crusting (MD = -3.53, 95% CI -4.55 to -2.52), and duration of erythema (MD = -3.16, 95% CI -3.58 to -2.74).

CONCLUSION

Er:Glass and CO2 fractional lasers demonstrate comparable efficacy and patient satisfaction for atrophic acne scars. Er:Glass offers significant advantages in reduced procedural pain and shorter recovery time, supporting its use as a safer alternative with similar effectiveness.

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