To investigate the clinical efficacy and safety of ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser and platelet-rich plasma(PRP) sequential therapy in the treatment of burn scar.

A total of 90 patients with postburn scar hyperplasia admitted Department of Burns, to Inner Mongolia Burn Research Institute, Inner Mongolia Baogang Hospital from January 2018 to August 2019 were selected as the research object. According to random number table method, the patients were divided into ultra pulse CO₂ lattice laser treatment group, ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser group and sequential group, with 30 cases in each group. In the ultra pulse CO₂ lattice laser treatment group, the treatment interval was two months, and a total of three ultra pulse CO₂ lattice laser treatments were performed. On the basis of ultra pulse CO₂ lattice laser treatment group, ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser treatment group was treated with long pulse width 1 064 nm Nd: YAG laser treatment once every two weeks at once month after the end of the first and second ultra pulse CO₂ lattice laser treatment, a total three ultra pulse CO₂ lattice laser treatments and four long pulse width 1 064 nm Nd: YAG laser treatment. In the sequential group, PRP was applied locally to the wound immediately after each ultra pulse CO₂ lattice laser treatment on the basis of ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser group. Clinical efficacy, visual analogue scale (VAS) score, vancouver scar scale (VSS) score, patient satisfaction, adverse reactions and recurrence were observed and compared among the three groups. Data were processed with chi-square test, Fisher′s exact probability test, LSD-t test, Kruskal-Wallis test, and Mann-Whitney test.

Two months after the third ultra pulse CO₂ lattice laser treatment, the total effective rate of the ultra pulse CO₂ lattice laser treatment group, the ultra pulse CO₂ lattice laser combined with long pulse with 1 064 nm Nd: YAG laser group and the sequential group were 22 patients (73.33%), 28 patients (93.33%) and 29 patients (96.67%), respectively. There was no statistically significant differences among the three groups (χ²=9.63, P=0.14). There was no significant difference in VAS score among the three groups before treatment (F=0.07, P=0.932). Two months after the first and second ultra pulse CO₂ lattice laser treatment, the overall differences among the three groups were statistically significant (F=12.04, 9.02; P<0.05). Two months after the third ultra pulse CO₂ lattice laser treatment, the VAS scores of the ultra pulse CO₂ lattice laser treatment group, the ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser group and the sequential group were (3.76±0.77), (1.35±0.43) and (1.28±0.39) points, respectively, and the overall difference among the three groups was statistically significant (F=59.09, P < 0.05). Compared with the ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser group and sequential group, the differences were statistically significant (t=6.61, 6.65; P<0.05). Compared with the sequential group, there was statistically significant difference in ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nmNd: YAG laser group (t=0.52, P<0.05). There was no statistically significant difference in VSS scores among three groups before treatment (F=0.10, P=0.90). Two months after the first and second ultra pulse CO₂ lattice laser treatment, the overall differences among the three groups were statistically significant (F=7.43, 17.29; P<0.05). Two months after the third ultra pulse CO₂ lattice laser treatment, the VSS scores of the ultra pulse CO₂ lattice laser treatment group, the ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser group and the sequential group were (5.43±1.06), (4.32±0.95) and (1.80±0.64) points, respectively, and the overall difference among the three groups was statistically significant (F=127.68, P < 0.05). The sequential group was compared with ultra pulse CO₂ lattice laser treatment group and ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser group, respectively, and the differences were statistically significant (t=15.60, 10.80; P<0.05). The difference between ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser group and ultra pulse CO₂ lattice laser treatment group was statistically significant (t=4.80, P<0.05). Two months after the third ultra pulse CO₂ lattice laser treatment, the satisfaction of patients in ultra pulse CO₂ lattice laser treatment group, ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser group and sequential group were 16 patients (53.33%), 30 patients (100.00%) and 24 patients (80.00%), respectively. The overall difference among the three groups was statistically significant (P < 0.05). In the ultra pulse CO2 lattice laser treatment group, 3 patients (10.00%) showed skin erythema after laser treatment, which disappeared spontaneously 2 months later. No adverse reactions occurred in the ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser group and sequential group. Follow-up for one year after laser treatment, the recurrence rates of ultra pulse CO₂ lattice laser treatment group, ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser group and sequential group were 8 patients (26.67%), 1 patient (3.34%) and 0(0), the overall difference among the three groups was statistically significant (P < 0.05). There were statistically significant differences between the ultra pulse CO₂ lattice laser treatment group and the ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser group and the sequential group (χ²=4.71, 7.07; P=0.030, 0.008).

Ultra pulse CO₂ lattice laser combined with long pulse width 1 064 nm Nd: YAG laser and PRP sequential therapy has reliable healing effect on burn scar, which can significantly improve scar morphology, color and softness, and improve aesthetic degree. It is superior to single therapy and worthy of clinical application.