Fractional CO₂ Laser to Treat Surgical Scars: A System Review and Meta-Analysis on Optimal Timing

Background: Surgical scars with textural changes can be disfiguring and uncomfortable for patients. Various laser therapies have shown promise in softening and flattening these scars. Therefore, the authors conducted a systematic review and meta-analysis on the efficacy of fractional CO₂ laser in treating surgical scars.

Objective: This study aims to present evidence from controlled trials investigating the efficacy of ablative carbon dioxide fractional laser in treating surgical scars.

Materials and methods: A literature search of Medline (via PubMed), Ovid, Web of Science, and Embase for relevant trials was conducted before March 2024. After assessing for inclusion, data extraction was performed using Population, Intervention, Comparison, Outcomes and Study criteria (PICOS). Quality, validity, and risk of bias were assessed using the RevMan5.3 risk of bias assessment tool.

Results: A total of 14 controlled trials involving 492 participants or postsurgical scars were included in the system review and meta-analysis. Both in RCT and non-RCT settings, fractional CO₂ laser therapy exhibited the same efficacious outcomes, with MD values of -0.63 (95% CI: -1.15 to -0.12; I² = 70%; p = 0.02) and - 1.86 (95% CI: -2.65 to -1.07; I² = 85%; p < 0.001), respectively. Moreover, furthermore analysis illustrated that initiating FRACTIONAL CO2 LASER treatment sessions at or within 1 month after surgery significantly reduced postoperative scars compared to control groups and groups on treatments initiated more than 3 months after surgery (MD: -1.66; 95% CI: -2.31 to -1.01; I² = 89%; p < 0.001 and MD: -1.93; 95% CI: -2.24 to -1.62; I² = 48%; p < 0.001). However, fractional CO₂ laser treatment administered over 3 months after surgery did not significantly improve postoperative scars (MD: -0.17; 95% CI: -0.56 to 0.21; I² = 37%; p = 0.37).

Conclusion: The systematic review and meta-analysis provide robust support for the efficacy of fractional CO₂ laser in treating surgical scars, particularly when administered at or within 1 month after surgery. One treatment session within 1 month after surgery also can produce significant results, but most clinical trials support 2-3 treatment sessions or more.