Comparison of dual-plane micro-drop injection of botulinum toxin type A with two traditional methods for treating hypertrophic scars in the tension zone: A long-term clinical application study.

[BACKGROUND] Patients with hypertrophic scarring tend to experience recurrence after treatment, which often occurs in areas of the body with high skin tension.

[AIMS] To evaluate better treatments aimed at reducing the risk of scar recurrence in areas of high skin tension.

[METHODS] Patients were randomly divided into the following three treatment groups: botulinum toxin type A (BTA) via dual-plane micro-drop injections, triamcinolone acetonide (TAC) suspension, and CO via fractional CO laser. Interventions were implemented in all three groups once a month for three consecutive sessions. After the final treatment, scarring was evaluated at 1, 3, 6, 12, and 24 months using the Patient and Observer Scar Assessment Scale (POSAS).

[RESULTS] The 3-month POSAS score for each scar indicator in the treatment groups was significantly lower than that in the preoperative groups (p < 0.001). The scar score in the TAC group decreased at 3 months and increased thereafter. For other groups, the scar score continually decreased at all time points according to the Patient Scar Assessment Scale. Based on the Observer Scar Assessment Scale, the scar score continuously decreased at all time points in the BTA group; in the TAC group, it decreased at 1 month and increased thereafter; and in the CO group, the scar score decreased at 3 months and subsequently stabilized.

[CONCLUSIONS] All three treatment methods were effective. However, the BTA group experienced a reduced risk of scar recurrence and maintained long-term treatment effects.