Treatment of Hypertrophic Scars Using Fractional CO2 Laser Alone in Comparison With Adding Botulinum Toxin Either Through Intralesional Injection or Assisted Drug Delivery (BTX and LADD)

Cairo University (CU)

Status: Completed

Conditions: Hypertrophic Scars

Treatments: Drug: Botulinum toxin type A (Botox®, Allergan)

Study type: Interventional

Funder types: Other

Identifiers

NCT07360483

MS-257 2024

Details and patient eligibility

About

The current study aimed to evaluate the effectiveness of fractional laser treatment alone and fractional laser combined with botulinum toxin A, delivered either through injections or topical application fractional laser-assisted drug delivery (FLADD) in hypertrophic burn scar

Full description

Burn injuries represent a major global health concern, often resulting in long term physical, psychological, and social consequences. Among the most challenging sequelae are hypertrophic scars, which arise from abnormal wound healing characterized by fibroblast hyperactivity, excessive collagen deposition and impaired extracellular matrix remodeling. These scars not only compromise skin pliability and aesthetics but also restrict mobility, leading to functional disability and reduced quality of life.

Traditional management strategies including surgical excision, corticosteroid injections, silicone gel, pressure therapy, and radiation have shown variable efficacy, with high recurrence rates and limited patient satisfaction. In recent years, minimally invasive modalities such as fractional CO2 laser therapy have gained prominence for their ability to remodel scar tissue and improve texture. Concurrently, botulinum toxin type A (BTXA) has emerged as a promising antifibrotic agent, exerting its effects by reducing wound tension, modulating fibroblast activity, and regulating collagen synthesis.

The integration of fractional CO2 laser with BTXA, delivered either intralesionally or via laser assisted drug delivery, offers a novel therapeutic approach aimed at enhancing scar pliability, contour and patient comfort. This study investigates the comparative efficacy of these modalities in the treatment of post burn hypertrophic scars, providing evidence to guide optimized clinical practice.

Enrollment: 48 patients

Sex: All

Ages: 18 to 70 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Scar Type: Clinically diagnosed hypertrophic burn scar not less than 4.5 cm
2. Minimum Scar Size: 4.5cm x 1 cm
3. Scar duration: At least 1 month old and not exceed 6 months.
4. Fitzpatrick Skin Type: II to IV
5. No Recent Scar Treatment: No scar treatment within the past 6 months
6. Healthy Skin: No active skin infections in the treatment area
7. Normal Neuromuscular Function: No history of neuromuscular disorders or medications affecting muscle function.

Exclusion criteria

• 1) Pregnancy /Lactation: Pregnant, lactating, or planning pregnancy within 6 months 2) patients did previous intervention for the scar for the last 6 months 3) Bleeding Disorders: Known cases of bleeding disorders 4) patients with allergic reaction to botulinum toxin or with neuromuscular junction diseases (eg, myasthenia gravis) 5) patients on medication that decrease neuromuscular transmission (eg, aminoglycosides, penicillamine, quinine, and calcium channel blockers).

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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48 participants in 3 patient groups

Received Fractional CO2 Laser with Intralesional Botox injection (FL + Inj. Botox).

Active Comparator group

Description:

* laser treatment was performed using ( DEKA SmartXide DOT, Italy). Treatment parameters included power (18-20W), dwell time (800-1000µs), spacing (500-600µm, 13% density), micro spot size (120µm), and 2-3 stacks, adjusted depending on scar height * For eye protection, eye goggles were used during the sessions. Patients were instructed to apply a full-spectrum sunscreen regularly. Topical antibiotic cream was applied twice per day for 5 days following the session, and emollients twice daily for two weeks * Immediately following laser treatment, Botulinum toxin type A (Botox Allergan, Irvine, CA; 100U vacuum-dried powder reconstituted in 2mL of sterile, preservative-free 0.9% saline to a concentration of 5U/0.1mL) was injected intralesionally into the scar tissue for Section 1. * A 24-gauge needle (0.3mm × 0.8mm) was used, and the injection was continued until slight blanching was visible. The dose was adjusted to 2.5 U/cm³ of the lesion, not exceeding 100 units per session

Treatment:

Drug: Botulinum toxin type A (Botox®, Allergan)

Received Fractional CO2 Laser Only (FL Only).

Active Comparator group

Description:

Fractional CO2 laser treatment was performed using ( DEKA SmartXide DOT, Italy). Treatment parameters included power (18-20W), dwell time (800-1000µs), spacing (500-600µm, 13% density), micro spot size (120µm), and 2-3 stacks, adjusted depending on scar height For eye protection, eye goggles were used during the sessions. Patients were instructed to apply a full-spectrum sunscreen regularly. Topical antibiotic cream was applied twice per day for 5 days following the session, and emollients twice daily for two weeks

Treatment:

Drug: Botulinum toxin type A (Botox®, Allergan)

Received Fractional CO2 Laser with Botulinum Toxin Assisted Drug Delivery (topical) (FL + Topical Bo

Active Comparator group

Description:

* Fractional CO2 laser treatment was performed using ( DEKA SmartXide DOT, Italy). Treatment parameters included power (18-20W), dwell time (800-1000µs), spacing (500-600µm, 13% density), micro spot size (120µm), and 2-3 stacks, adjusted depending on scar height (Tawfic et al., 2022). For eye protection, eye goggles were used during the sessions. Patients were instructed to apply a full-spectrum sunscreen regularly. Topical antibiotic cream was applied twice per day for 5 days following the session, and emollients twice daily for two weeks. * Immediately following laser treatment, Botulinum toxin type A (Botox Allergan, Irvine, CA; 100U vacuum-dried powder reconstituted in 2mL of sterile, preservative-free 0.9% saline to a concentration of 5U/0.1mL) -• Immediately following laser treatment for Section 3, topical Botulinum toxin (prepared at the same concentration 2.5 U/cm³ of the lesion as for intralesional injection and adjusted to 2.5 U/cm³) was applied to the treated area topically

Treatment:

Drug: Botulinum toxin type A (Botox®, Allergan)