Laser treatment of burn scars
Key Points
- Fractional CO2 laser produces significant, sustained improvements in scar elasticity, thickness, appearance, and symptoms for mature hypertrophic burn scars, with effects lasting at least 6 months [2]
- PDL is safe and effective as an alternative to excisional surgery for facial hypertrophic burn scars, with over a decade of experience supporting its role [7][8]
- Adverse events from fractional CO2 laser are uncommon (2.4% of sessions), predominantly mild, and self-resolving [6]
- Consider combination PDL + AFCL for immature hypertrophic scars where combined treatment shows the greatest incremental benefit [4]
- Integrate laser therapy into a multimodality program: pressure therapy, silicone, and intralesional agents remain important [9][10]
- Start conservative scar management (pressure garments, silicone) early after wound closure and reserve laser therapy for persistent symptoms after adequate conservative treatment [11][12]
Overview
Hypertrophic scarring affects up to 70% of burn survivors [14] and remains the leading driver of long-term morbidity after burn injury. Laser therapy, particularly fractional ablative CO2 laser (AFCL) and pulsed dye laser (PDL), has emerged as a promising modality for improving scar pliability, appearance, and symptoms. It functions most effectively within a multimodality scar management program rather than as a standalone treatment.
Randomized controlled trial evidence
The ELABS (Early Laser for Burn Scars) trial represents the strongest randomized controlled evidence [1]. This multicenter RCT at seven UK centers randomized 153 participants to standard care plus three PDL treatments versus standard care alone. At six months, early PDL showed statistically significant improvement in patient-rated scar quality (POSAS, p=0.041) and participant perception of scar change (p=0.01). However, there were no significant differences in quality of life, observer-rated scar quality, or objective color measurement, suggesting that laser therapy's primary benefit may be patient-perceived rather than clinician-assessed [1].
Karimi Kivi et al.'s single-blinded RCT directly compared PDL alone, AFCL alone, and their combination for hypertrophic burn scars [4]. All groups showed significant VSS improvement, but combination therapy produced the most highlighted improvement, particularly in vascular bed and pliability. Combined treatment effectiveness was most pronounced in immature scars [4].
Fractional ablative CO2 laser
Miletta et al. conducted a multicenter prospective study of AFCL for mature hypertrophic burn scars [2]. Twenty-six subjects received at least one treatment, with 22 completing three treatments. Statistically significant objective improvements were demonstrated in elastic stretch, elastic recovery, extensibility, and scar thickness (all p<0.01). Patient- and physician-reported scar appearance and pain/pruritus were also significantly improved, with no regression for at least six months after treatment [2].
Pulsed dye laser
Donelan and Parrett's experience with PDL for facial burn scars over 10 years showed the laser eliminated the need for excisional surgery in all 57 patients treated, with combination z-plasty used in 60% to relieve scar tension [7][8].
Systematic reviews
A 2025 systematic review and network meta-analysis by Li et al. compared PDL, AFCL, and combination therapy across eleven studies [3]. PDL showed significant reduction in total Vancouver Scar Scale scores compared to combination therapy (MD = -0.90, 95% CI: -1.77 to -0.04), while AFCL showed no significant difference. The finding that PDL monotherapy may outperform combination therapy challenges assumptions about additive benefit of dual-laser protocols [3].
Safety
Won et al. reviewed 544 fractional CO2 laser sessions across 170 patients and reported only 13 adverse events (2.4%), predominantly increased pain (0.9%), erythema (0.6%), and epidermal sloughing (0.7%), with 97% of patients reporting symptom improvement [6].
Integration with multimodal therapy
The 2014 consensus report by Anderson et al. positioned ablative fractional photothermolysis as a breakthrough in traumatic scar treatment [5]. Tredget et al. emphasize that laser interventions show promise but do not provide a definitive solution alone [9]. Bernabe et al.'s systematic review found that combinations of intralesional agents (particularly triamcinolone with 5-fluorouracil) with laser therapy can provide additive benefit for refractory hypertrophic scars and keloids [10]. Conservative therapy remains foundational, supported by Engrav et al.'s 12-year randomized study of pressure garments [11] and Ahn et al.'s work on silicone gel [12][13].
Controversies and Evidence Gaps
The optimal number of laser sessions remains undefined, with studies ranging from single treatments to 17 sessions and no dose-response curve established. The ELABS trial found benefit at six months but noted that longer follow-up of two or more years is needed to determine durability [1]. Whether ablative (CO2) or non-ablative (PDL) laser produces superior outcomes is unresolved; Li et al.'s meta-analysis suggests PDL monotherapy may be comparable or superior to combination protocols [3]. Cost-effectiveness has not been rigorously studied, and the lack of quality-of-life improvement in the ELABS trial raises questions about value relative to simpler interventions. Timing of intervention (early immature scars versus mature refractory scars) may fundamentally alter treatment response, but comparative timing studies are lacking [4]. Patient selection criteria beyond "failed conservative therapy" remain poorly defined.
References
[1] Brewin MP et al. (2025). Early Laser for Burn Scars (ELABS) - Randomised controlled trial of pulsed dye laser treatment and standard care versus standard care alone for the treatment of hypertrophic burn scars. PMID: 40319828 [2] Miletta N et al. (2021). Fractional Ablative Laser Therapy is an Effective Treatment for Hypertrophic Burn Scars: A Prospective Study of Objective and Subjective Outcomes. PMID: 31469749 [3] Li P et al. (2025). Pulsed dye laser, fractional CO2 laser, or combination for burn scar treatment: a systematic review. PMID: 41003790 [4] Karimi Kivi M et al. (2024). The efficacy, satisfaction, and safety of carbon dioxide (CO2) fractional laser in combination with pulsed dye laser (PDL) versus each one alone in the treatment of hypertrophic burn scars: a single-blinded randomized controlled trial. PMID: 38376542 [5] Anderson RR et al. (2014). Laser treatment of traumatic scars with an emphasis on ablative fractional laser resurfacing: consensus report. PMID: 24336931 [6] Won P et al. (2023). Treatment of Hypertrophic Burn Scars With Laser Therapy: A Review of Adverse Events. PMID: 37856225 [7] Donelan MB et al. (2008). Pulsed dye laser therapy and z-plasty for facial burn scars: the alternative to excision. PMID: 18434818 [8] Parrett BM, Donelan MB. (2010). Pulsed dye laser in burn scars: current concepts and future directions. PMID: 20022430 [9] Tredget EE et al. (2014). Biology and principles of scar management and burn reconstruction. PMID: 25085089 [10] Bernabe RM et al. (2024). Combining scar-modulating agents for the treatment of hypertrophic scars and keloids: A systematic review. PMID: 37979279 [11] Engrav LH et al. (2010). 12-Year within-wound study of the effectiveness of custom pressure garment therapy. PMID: 20537469 [12] Ahn ST et al. (1991). Topical silicone gel for the prevention and treatment of hypertrophic scar. PMID: 2009067 [13] Ahn ST et al. (1989). Topical silicone gel: a new treatment for hypertrophic scars. PMID: 2529659 [14] Finnerty CC et al. (2016). Hypertrophic scarring: the greatest unmet challenge after burn injury. PMID: 27707499