Botulinum Toxin Type a Injection to Prevent Keloid Recurrence
- Conditions
- Scar Keloid
- Interventions
- Drug: 0.9% Sodium Chloride InjectionDrug: Botulinum Toxin Type A Injection [Botox]
- Registration Number
- NCT05072821
- Lead Sponsor
- National Cheng-Kung University Hospital
- Brief Summary
The prospective, split-scar, double-blind, randomized controlled study will enroll the patients who are older than 20 years with progressive keloid lesion which is symmetric. Botulinum toxin A will be injected into half of each keloid revision wound immediately after skin closure. The scars will be assessed at 1-year follow-up with Vancouver Scar Scale (VSS), Patient and Observer Scar Assessment Scale (POSAS), and the Cutometer.
- Detailed Description
Continuous variables will be reported as the mean ± standard deviation(SD). Each aspect of the VSS score, POSAS score, and the Cutometer parameters of each scar half between the BTA and control groups will be analyzed longitudinally using the paired t test. The interrater consistency will be evaluated using the Spearman rho. All analyses will be performed with IBM SPSS Version 23.0 (IBM Corp., Redmond, Wash.). A value of p \< 0.05 is considered to indicate statistical significance.
The sample size was calculated based on the results of the investigators' aforementioned study published in 2019. Thirty patients underwent keloid revision and then received radiation therapy based on our treatment protocol. The postoperative Vancouver Scar Scale score was 4.15 ± 1.74. If treatment could improve VSS score by 1, which was considered clinically significant, approximately 26 patients would have been necessary to provide a result with a real significance (using the same SD and considering the standard α error of 0.05 and a power of 0.8). Assuming a 20% non-compliance rate for follow-up evaluation, the sample size was increased to 32 patients.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 28
- Adult (20 years or older)
- Progressive keloid lesion that is bilaterally symmetric, mandibular area, anterior chest or suprapubic area, for example
- At least 4 cm in length
- Repeated or uncontrolled recurrence, and unendurable symptoms with poor response to conservative modalities
- Valid written informed consent provided for surgery and trial inclusion
- Allergy to botulinum toxin
- Previous botulinum toxin injection at the lesion within 6 months before enrollment
- Myasthenia gravis
- Focal infection signs
- Pregnant or breastfeeding woman
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description 0.9% saline injection side 0.9% Sodium Chloride Injection The 0.9% saline will be injected into the dermal layer before skin closure in keloid excision surgery. The dosage is 0.16 mL/cm. Botulinum Toxin type A injection side Botulinum Toxin Type A Injection [Botox] The Botulinum Toxin type A will be injected into the dermal layer before skin closure in keloid excision surgery. The concentration of Botulinum Toxin type A is 100 units in 2 mL and dosage is 8 units/cm. The maximal dose is 100 units for each participant.
- Primary Outcome Measures
Name Time Method Keloid recurrence One year The recurrence of keloid will be determined by clinical examination evaluated by a dermatologist.
- Secondary Outcome Measures
Name Time Method Subjective symptoms 3, 6, 9 and 12 months The subjective symptoms will be measured by the Patient Scale of the Patient and Observer Scar Assessment Scale. The Patient Scale consists six items and scores from 1 to 10 for each items. The score of 1 means much alike the normal skin and the score of 10 means worst imaginable scar.
Objective symptoms 3, 6, 9 and 12 months The subjective symptoms will be measured by the Observer Scale of the Patient and Observer Scar Assessment Scale. The Observer Scale consists six items and scores from 1 to 10 for each items. The score of 1 means much alike the normal skin and the score of 10 means worst imaginable scar.
Vancouver Scar Scale 6 and 12 months One dermatologist will evaluate the scar with the Vancouver Scar Scale. The Vancouver Scar Scale consists 4 items. The minimum score is 0, which means the scar is much alike normal skin. The maximal score is 13, which means purple, hyperpigmentation, contracture and elevated scar.
Scar firmness 6 and 12 months The scar firmness is determined by the Cutometer parameter R0. R0 is maximum amplitude of the curve (the total elongation). The larger R0 is, the softer the scar is.
Trial Locations
- Locations (1)
National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University
🇨🇳Tainan, Taiwan