Lasers for the prevention and treatment of hypertrophic scars: a review of the literature

Lasers and Intense Pulsed Light for the Treatment of Pathological Scars: A Network Meta-Analysis

BACKGROUND

Laser and intense pulsed light (IPL) therapies have shown promising effects on pathological scars, but the comparative effectiveness of laser and IPL therapies has not yet been studied.

OBJECTIVES

The aim of this study was to compare and rank the efficacy of laser and IPL therapies to determine the most effective treatment method for pathological scars.

METHODS

Relevant studies published up to February 2022 were identified by searching PubMed, Web of Science, Cochrane Library, CNKI, and Wanfang databases. We defined Vancouver Scar Scale score as the primary outcome. Both frequentist and Bayesian approaches were used to perform a network meta-analysis.

RESULTS

We included 25 trials with a total of 1688 participants. The rankings based on the surface under the cumulative ranking curve for the Vancouver Scar Scale score based on the Bayesian approach suggested IPL + CO2 (96.43%) > pulsed dye laser (PDL) + 1064-nm Nd:YAG (yttrium aluminum garnet) laser (86.21%) > PDL + CO2 (82.15%) > CO2 (58.97%) > 1064-nm Nd:YAG (57.03%) > PDL (52%) > 532-nm Nd:YAG (33.28%) > Er:YAG + IPL (28.38%) > Er:YAG (26.56%) > IPL (15.03%) > control (13.97%). The ranking results based on the frequentist approach were basically consistent with those based on the Bayesian approach.

CONCLUSIONS

The results of the network meta-analysis showed that the combination of IPL and CO2 laser has the highest probability of being the most effective intervention. However, our conclusions must be interpreted with caution due to the relatively few evaluation indicators included in our study. Future well-designed randomized controlled trials with large sample sizes are required to confirm our conclusions.

LEVEL OF EVIDENCE: 4

The efficacy and safety of low-energy carbon dioxide fractional laser use in the treatment of early-stage pediatric hypertrophic scars: A prospective, randomized, split-scar study

BACKGROUND

Various laser therapies have been introduced in scar management. However, pain during treatment has limited the application of laser therapy in pediatrics.

OBJECTIVES

To evaluate whether the use of the low-energy mode of a carbon dioxide (CO₂ ) laser improves hypertrophic scars in a pediatric population.

METHODS

This prospective, randomized, split-scar trial was designed to assess the safety and efficacy of low-energy CO₂ laser use. Patients aged <12 years with hypertrophic scars were enrolled. Each hypertrophic scar was equally divided into three parts: the two ends of each scar were randomly assigned to control and experimental groups, and the center portion was considered a transition zone and was not included in the analysis. A total of three laser treatments were performed at 1-month intervals. Scar scale scores 6 months after the final treatment was the primary outcome. Additionally, the Visual Analog Scale (VAS) was used to evaluate pain after each treatment.

RESULTS

Of the 23 patients enrolled, 20 completed the study. The total Patient and Observer Scar Assessment Scale (POSAS) score at the 6-month follow-up was significantly lower for the treated site (44.95 for the treated group vs. 64.85 for the control group, p < 0.0001). Both the patient and observer POSAS scores showed an obvious difference between the treated and control groups (19.95 vs. 29.95 for patient scores, respectively, p < 0.0001, and 26.00 vs. 34.90 for observer scores, respectively, p < 0.0001). All observer and patient scores describing pain, pruritus, color, stiffness, and thickness were statistically different and favored the treated site. No significant difference was found in patient score of irregularity. The average VAS therapeutic pain score was 3.5 ± 1.43 out of 10.

CONCLUSIONS

Low-energy CO₂ fractional laser therapy improved hypertrophic scars in a pediatric population. Therefore, for children with hypertrophic scar, low-energy CO₂ laser with less procedure pain may be more appropriate.

Sequelae After Involution of Superficial Infantile Hemangioma: Early Intervention with 595-nm Pulsed Laser Combined with 755-nm Long-Pulsed Alexandrite Laser versus Wait-and-See

Background and Objective

Infantile haemangioma (IH) is the most common benign tumor in children. At present, pulsed dye laser (PDL) has made great progress in the treatment of superficial IH, showing good safety and effectiveness. But some doctors think that superficial IH should choose to wait-and-see. However, studies have reported that most of the IH after resolution still has residual disease, and thickness seems to be an important factor. Therefore, the purpose of this study is to investigate the relationship between Sequelae and thickness after superficial IH involution. In addition, compare the Sequelae difference between 595-nm pulsed laser combined with 755-nm long-pulse alexandrite laser treatment and wait-and-see.

Materials and Methods

This retrospective observational study included patients with superficial IH evaluated in the past 6 years and divided them into a laser group and an observation group.

Results

The incidence of sequelae in the laser group was 44.6%, and the incidence of sequelae in the observation group was 69.5%. The incidence of Sequelae of superficial IH in the laser group was significantly lower than that in the observation group (χ ²-test, χ ²=10.790, P <0.001). In the observation group, the average A scores of the three thickness subgroups (<2mm, 2-5mm, and >5mm) were 4.38, 3.39, and 1.80, and there were significant differences in the A scores between the three groups (Kruskal-Wallis, p<0.05). There is a significant difference in the A score between the laser group and the observation group in the superficial IH with a thickness of 2-5 mm and>5mm (Wilcoxon rank sum test, P<0.05).

Conclusion

This retrospective study showed that the degree of Sequelae of superficial IH after involution is related to its thickness. In addition, the early intervention of 595-nm pulsed laser combined with 755-nm long-pulse alexandrite laser can reduce the incidence and extent of sequelae.