Evaluating the effectiveness and safety of pulsed dye laser alone, the combination of pulsed dye laser and botulinum toxin type A, and the combination of pulsed dye laser and triamcinolone injection in the treatment of hypertrophic and keloid scars: a three-arm randomized controlled clinical trial

To evaluate the efficacy and safety of pulsed dye laser (PDL) alone, the combination of PDL and botulinum toxin type A (BTA) injection, and the combination of PDL and triamcinolone injection in the treatment of hypertrophic scars and keloids. In this three-arm, single-blind randomized controlled clinical trial, 10 patients over 18 years old with hypertrophic scars or keloids were enrolled. Each patient had at least 3 lesions, each measuring at least 10 x 10 square centimeters or 10 centimeters long. In the first treatment session, each of the 3 lesions was randomly assigned to one of three interventions: PDL (control), PDL with BTA injection (at a concentration of 2 units/cm2), or PDL with triamcinolone injection (20 mg/cc). All the interventions carried out in the groups have been repeated in three sessions. One follow-up visit took place one month after the last session, without any intervention. Clinical images of the lesions were collected during the treatment sessions. A blinded dermatologist assessed the effectiveness of the treatment using a physician global assessment score and the Vancouver Scar Scale (VSS). Patient satisfaction and any side effects were recorded during follow-up visits. The average age of the cases under consideration was 36.00 +/- 13.23 years. In terms of gender, 4 out of the cases (40.00%) were females. During the initial session, the mean VSS scores in the PDL, PDL-BTA, and PDL-Triamcinolone groups were 7.90 +/- 1.52, 7.10 +/- 0.56, and 7.30 +/- 0.24, subsequently. These scores decreased to 7.30 +/- 1.34, 4.90 +/- 1.37, and 4.30 +/- 0.95 in the PDL, PDL-BTA, and PDL-Triamcinolone groups, respectively (P = 0.001). The group that received both PDL and BTA showed the most significant enhancement in pliability (P = 0.001) and regarding scar vascularity and height the most improvement was related to PDL-triamcinolone group (P = 0.01 and 0.001, respectively). In addition, the level of physician's satisfaction in the PDL-BTA and PDL-Triamcinolone groups were significantly higher than in the PDL group (P = 0.004). However, no significant difference was seen between the combined treatments. Finally, no significant side effects were observed in the studied methods during various treatment sessions. The findings of the study revealed that utilizing a combination of two modalities yielded better outcomes compared to a single treatment approach. Specifically, the combination of PDL and BTA demonstrated greater improvement in scar pliability. On the other hand, when considering scar vascularity and height, the combination of PDL with triamcinolone exhibited more significant enhancement.