CO₂ Laser TAC±5-FU for Hypertrophic Scars: Split-Scar RCT

Background: Hypertrophic burn scars cause significant pain, pruritus, stiffness, functional impairment, and psychosocial distress. Fractional CO₂ laser therapy is widely used to improve scar pliability and texture by creating microthermal channels that remodel collagen and enhance drug penetration. Triamcinolone acetonide (TAC) is the current standard pharmacologic therapy, but clinical improvement is often incomplete. Multiple randomized trials and meta-analyses demonstrate that intralesional 5-fluorouracil (5-FU) combined with TAC yields superior scar flattening, improved pliability, and fewer steroid-related side effects compared with TAC alone. However, no study has evaluated whether this synergy translates to topical use when delivered through fractional CO₂ laser–assisted drug delivery (LADD). This represents a major gap in the field, especially given growing national use of LADD for hypertrophic scar management.

This prospective, triple-blinded, randomized split-scar clinical trial directly addresses this gap by comparing CO₂ laser–assisted TAC + 5-FU versus CO₂ laser–assisted TAC alone, generating the first Level I evidence for combined antimetabolite–steroid therapy delivered via LADD.