Objectives
For intractable hypertrophic scar, multimodal treatment is a promising strategy. We investigated the clinical efficacy of combination therapy of intralesional injection (ILI) and nonablative fractional LASER (NAFL), compared to ILI therapy alone. 
Methods
Total of 57 patients with hypertrophic scars or keloids were enrolled. Total of 19 patients were excluded due to age and medical comorbidities. ILI monotherapy group (n=21) and ILI plus NAFL group (n=17) were evaluated. ILI was performed using1:1 Triamcinolone with lidocaine with 0.1cc/cm2. NAFL was performed using 1550nm, erbium-glass fractional LASER with 50mJ x 40spot/cm2. All treatments were 4 weeks apart.The outcome was evaluated with 1) number of treatment sessions until treatment endpoint, and 2) Patient and Observer Scar Assessment Scale (POSAS). Recurrence or treatment failure was defined as no improvement after 6 months of treatment completion. The data was analyzed with independent sample t-test and recurrence rate was assessed with chi-square test.
Results
Mean number of treatment sessions showed statistical significance (6.95 in control group vs 5.47 in combined therapy group, p=0.042). Baseline patients scale (PS) did not show significance (38.38 versus 36.18, p=0.580). However, statistical significance was found between two groups (23.77 versus 13.36, p=0.0004). Baseline mean observer scale (OS) were not significant (42.08 versus 38.1, p=0.302). At six months post therapy, Mean OS showed significance (24.15 versus 17.64, p=0.046). Total scale (PS + OS) showed no difference at baseline (24.15 versus 17.64, p=0.347), but showed significant difference at six months post therapy (47.92 versus 31.00, p=0.002). The recurrence rate was 38.1% in control group and 35.3% in combined therapy group (p=0.859). 
Conclusion
Combined therapy with fractional laser and steroid intralesional injections showed significant improvement of scar quality than control group. Ideal laser parameters and treatment sequence should be established with further investigation.

4 - Combination therapy using nonablative fractional laser and intralesional triamcinolone injection for hypertrophic scars and keloids treatment