Onabotulinum Toxin A in Direct Brow Lift
- Conditions
- Direct Brow LiftScarring
- Interventions
- Other: No intervention (placebo)
- Registration Number
- NCT04383912
- Lead Sponsor
- Nova Scotia Health Authority
- Brief Summary
The brow lift is a surgical procedure that has been practiced for several decades. A typical indication is brow ptosis, which can be secondary to involutional changes or facial nerve palsies. Several techniques have been described, including direct, mid-forehead, coronal, and endoscopic approaches. Of these options, the direct brow lift allows for predictable post-operative brow contour and excellent control over the degree of lift achieved. As with any surgical procedure, with direct brow lift comes known undesirable post-operative outcomes, the most common of which is forehead paresthesia from supraorbital nerve damage. Other complications include alopecia and brow asymmetry. However, one of the main critiques of direct brow lift remains the poor cosmesis that can result from scarring just above the brow. A study conducted by Cho et al. concluded that of the main surgical techniques currently employed for treatment of brow ptosis, direct brow lifts held the highest rates of visible scarring.
Scarring can significantly impair an individuals' quality of life. This is particularly true of facial scarring, which is often difficult to conceal. Much research has been conducted in the area of treating postoperative, traumatic, and burn-related scarring. Cadet et al completed a randomized controlled trial using topical silicone gel for direct brow lift-related scarring, given the known benefit of silicone gel sheeting for the same, but did not find a significant difference between treatment and control groups. Some effective techniques described in the literature to date include long-pulsed non-ablative Nd:YAG laser, as well as intralesional steroid injection. On the rise are studies looking into the use of botulinum toxin A for treatment of unfavourable scarring and improved facial cosmesis.
Botulinum toxin is a neuromodulatory agent that has garnered usage in a variety of therapeutic and cosmetic settings. More recently, injection of botulinum toxin as a means to reduce scarring and improve outcomes in wound healing has been investigated. Several studies, including two large metaanalyses, have shown this to be an effective method of treatment. Proposed mechanisms include increased apoptosis and suppressed proliferation of fibroblasts treated with botulinum toxin, modulated via the PTEN/PI3K/Akt pathway. Park et al added to the in vitro literature by demonstrating that fibroblasts treated with botulinum toxin A produced fewer extracellular matrix proteins and pro-fibrotic factors compared to untreated cells. Another underlying mechanism that results in suboptimal wound healing is the constant contraction and relaxation of facial muscles, causing repetitive microtrauma that ultimately increases inflammation and impairs wound healing. It therefore stands to reason that by temporarily paralyzing local musculature during the post-operative period, collagen maturation can take place uninterrupted by excessive tensile forces.
Despite scarring being a widely known and undesirable complication of direct brow lift surgery, there have been no studies to date examining the use of onabotulinum toxin injection to reduce said scarring and improve outcomes. With this double masked, prospective, randomized controlled trial, the investigators aim to determine whether injection of onabotulinum toxin immediately following direct brow lift surgery can improve scores on validated patient and observer scar scales.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- ACTIVE_NOT_RECRUITING
- Sex
- All
- Target Recruitment
- 16
Not provided
Not provided
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description onabotulinum toxin A group (brow) Botox Injectable Product Product name: Onabotulinum toxin A (Botox A, Allergan), 50 unit vials Product code: 93094EC Description: The side randomized to treatment will receive an injection of 20 units of onabotulinum toxin A as the final step of a direct brow lift surgery. The surgeon will visually divide the surgical incision in half, and divide the volume of the injection evenly between the two sides. This will be a one time administration. placebo group (brow) No intervention (placebo) Product name: normal saline Description: The side randomized to placebo will receive an injection of normal saline as the final step of a direct brow lift surgery. The surgeon will visually divide the surgical incision in half, and divide the volume of the injection evenly between the two sides. This will be a one time administration.
- Primary Outcome Measures
Name Time Method Effect of onabotulinum toxin A on scarring in direct brow lift surgery 1 to 12 months * At 1 month following surgery, photographs will be taken of both brows. The patient will then be given a mirror, and under consistent lighting conditions and in a private setting, will complete the Patient Scar Assessment Scale (PSAS) and Visual Analog Scale (VAS), after adequate explanation of each parameter. These scores will be combined for a total score ranging from 7 to 70, again with lower numbers indicating higher patient satisfaction. A masked lay observer (consistent person with every patient) will also complete the VAS.
* The above step will be repeated at 3 months, 6 months, and 12 months after surgery, as well as the following additional steps. Scars will be graded by a masked observer using the Observer Scar Assessment Scale (OSAS), Observer Modified Scar Assessment Scale (OMSAS), and Visual Analog Scale (VAS). These scores will be combined for a total score ranging from 11 to 81, with lower scores indicating better outcome.Degree of brow lift achieved Pre-operative to 12 months Pre-operative, intra-operative, and post-operative (at month 1, 3, 6, and 12) photographs will be taken for all participants. ImageJ software will be used to analyze the photos and measure the degree of brow lift achieved on each side, to ensure this has not been affected by botulinum toxin injection. This will be measured from the pupillary light reflex to the upper border of the eyebrow (in mm). These measurements will be done by a masked observer.
- Secondary Outcome Measures
Name Time Method
Trial Locations
- Locations (1)
Eye Care Centre, Victoria General Hospital
🇨🇦Halifax, Nova Scotia, Canada