Fractional CO₂ Laser for Pediatric Hypertrophic Scars: Lessons Learned from a Prematurely Terminated Split-Scar Trial

Assessing hypertrophic scar (HTS) interventions is challenging because scars continue to undergo dynamic changes. A split-scar design can distinguish treatment effects from natural HTS evolution. Despite promising reports of ablative fractional CO₂ lasers (AFCO₂Ls) for HTS, split-scar evidence, particularly in pediatric scars, remains limited.

To explore the feasibility of a split-scar design in assessing AFCO₂L's impact on pediatric HTS and to identify potential trends in treatment outcomes.

Initially designed as a prospective single-center split-scar randomized controlled trial, our study transitioned to a feasibility trial due to recruitment challenges. Pediatric patients aged 1-17 years with HTS suitable for split-scar evaluation received three AFCO₂L treatments at 6-8-week intervals, with outcomes assessed using the Vancouver Scar Scale (VSS), SCAR-Q, and Cutometer.

Recruitment was limited by COVID-19 restrictions, concerns about general anesthesia for split-scar treatment, and low interest in divided-scar interventions, resulting in only 6 participants with 9 scars enrolled, far below the target sample size of 44. This small heterogeneous sample precluded meaningful clinical outcome analysis.

Our feasibility trial highlights challenges in conducting rigorous pediatric HTS studies and the need for careful interpretation of evidence due to potential publication bias. Future trials should focus on tailored recruitment and comprehensive reporting to improve feasibility and reliability.