[Effect of pulsed dye laser in combination with ultra-pulsed fractional carbon dioxide laser in treating pediatric burn scars at early stage]

Objective: To explore the effect of combined application of pulsed dye laser (PDL) and ultra-pulsed fractional carbon dioxide laser (UFCL) in the treatment of pediatric large burn scars at early stage. Methods: One hundred and twenty pediatric patients with large burn scars at early stage conforming to the study criteria were admitted to the People's Hospital of Hunan Province from January 2016 to December 2019. Their data were retrospectively analyzed by the method of single case-control study. There were 78 males and 42 females with age of (4.2±0.8) years and scar area of (100.3±0.7) cm(2). PDL combined with UFCL was used for the first time. The treatment interval of PDL was a month and the treatment interval of UFCL was 3 months. The total treatment cycle was 6 months, with 2 PDL treatments alone and two combined treatments. Before the first combined treatment and 6 months after two combined treatments, the curative effect was assessed using Patient and Observer Scar Assessment Scale (POSAS) by doctors and family members of pediatric patients. Satisfaction degrees of the family members of pediatric patients were recorded, and the overall satisfaction rate was calculated 6 months after two combined treatments. The adverse effects during the whole treatment course were recorded. Data were statistically analyzed with paired t test. Results: (1) Six months after two combined treatments, the scores of pediatric patients' scar vascularity, pigment, thickness, relief, pliability, surface area, and overall valuation in POSAS by doctors and the scores of pain, itch, color, stiffness, thickness, irregularity, and overall valuation in POSAS by family members of pediatric patients were all significantly lower than those before the first combined treatment (t=16.6, 16.0, 16.9, 14.9, 20.8, 29.3, 30.7, 20.4, 29.3, 18.1, 27.9, 25.8, 20.8, 45.3, P<0.01). The overall evaluation scores by doctors were (8.1±0.8) and (2.7±0.6) points, and the overall evaluation scores by family members of pediatric patients were (8.2±0.8) and (2.4±0.5) points respectively before the first combined treatment and six months after two combined treatments. (2) Six months after two combined treatments, 110 (92%) family members of pediatric patients were very satisfied with the curative effect, 6 (5%) family members of pediatric patients were satisfied, and 4 (3%) family members of pediatric patients were relatively satisfied with no unsatisfied reported. The overall satisfaction rate was 97% (116/120). (3) During the treatment, pruritus and rash appeared in 5 pediatric patients 3 to 4 days after the first treatment; pigmentation appeared in 3 pediatric patients 3 weeks after the first treatment; pruritus and vesicle appeared in 1 patient 1 week after the third treatment. No adverse effects such as aggravated scar or infection were observed on the wounds. Conclusions: In treating pediatric large burn scars at early stage, PDL combined with UFCL has demonstrated significant effect with short treatment cycle, few adverse effects. The combined treatment can alleviate symptoms and improve the quality of pediatric patients' life, and is worthy to be popularized and applied in clinic.

[Clinical comparative study of pulsed dye laser and ultra-pulsed fractional carbon dioxide laser in the treatment of hypertrophic scars after burns]

Objective: To compare the efficacy and safety of pulsed dye laser (PDL) and ultra-pulsed fractional carbon dioxide laser (UFCL) in treating hypertrophic scars after burns. Methods: Two hundred and twenty one patients with hypertrophic scar after burns conforming to the study criteria were admitted to our unit from February 2015 to October 2017, and their data were retrospectively analyzed. Patients were divided into group PDL (n=122) and group UFCL (n=99) according to the treatment method. Patients in group PDL were treated with PDL once every 3-4 weeks. Patients in group UFCL were treated with UFCL once every 6-12 weeks. Patients in both groups were treated until 12 months after having scar. Scars were scored by Vancouver Scar Scale (VSS) before and after treatment. Patients' pain was evaluated by Visual Analogue Scale (VAS) method before and after treatment. Blood flow in scar was monitored and recorded before treatment and in treatment months 6 and 12. Satisfaction degree of patients was recorded 3-6 months after treatment, and the satisfaction rate was calculated. Adverse reactions including duration of erythema/purpura, VAS in treatment, and loss of working time were recorded. Data were processed with one-way analysis of variance, t test, and Chi-square test. Results: (1) VSS scores of patients in groups PDL and UFCL after treatment were significantly lower than those before treatment in the same group (t=11.34, 12.77, P<0.05). The decreasing VSS scores of patients after treatment in groups PDL and UFCL were (5.8±1.1) and (6.0±1.4) points, respectively, and there was no statistically significant difference between the two groups (t=1.91, P>0.05). (2) VAS of patients in groups PDL and UFCL after treatment were significantly lower than those before treatment in the same group (t=7.12, 5.23, P<0.05). The decreasing VAS of patients after treatment in groups PDL and UFCL were (4.0±0.6) and (3.2±1.3) points, respectively, and there was no statistically significant difference between the two groups (t=1.93, P>0.05). (3) Scar blood flow of patients in group PDL in treatment months 6 had no obvious change compared with that before treatment (t=1.59, P>0.05), while that in treatment months 12 significantly decreased compared with that before treatment and that in treatment months 6 (t=3.17, 6.96, P<0.05). Scar blood flow of patients in group UFCL in treatment months 6 significantly increased compared with that before treatment (t=6.01, P<0.05), while that in treatment months 12 significantly decreased compared with that in treatment months 6 (t=4.52, P<0.05), but had no obvious change compared with that before treatment (t=0.92, P>0.05). (4) The satisfaction degree of patients in group PDL was 80.3% (98/122), which in group UFCL was 76.8% (76/99), and there was no statistically significant difference between the two groups (χ(2)=0.97, P>0.05). (5) The duration of erythema/purpura of patients in group PDL was (5.2±0.7) d, significantly shorter than (6.1±0.5) d in group UFCL (t=2.49, P<0.05). The VAS of patients in group PDL during treatment was (1.9±0.9) points, significantly lower than (4.7±0.4) points in group UFCL (t=4.85, P<0.05). Loss of working time of patients in group UFCL was (9.17±0.72) d, which was significantly longer than (3.96±0.23) d in group PDL (t=3.17, P<0.05). Conclusions: PDL and UFCL have definite effects on hypertrophic scar, while PDL with light pain, minor wound, and fast recovery time, is safe and effective for treatment of early hypertrophic scar and worthy of clinical promotion and application, especially for children and patients with poor pain tolerance.