Skin Biomechanical Changes after Injection of Onabotulinum Toxin A: Prospective Assessment of Elasticity and Pliability

Using Neuromodulators to Improve Scar Formation, Keloids, Rosacea, and Antiaging

BACKGROUND

Botulinum toxin A (BoNT-A) treatment has many uses in dermatology. Its mechanism of action and long-term effects for scar formation, rosacea, and antiaging are still being investigated.

OBJECTIVE

To conduct a literature review on BoNT-A to further investigate its use in scar formation, rosacea, and antiaging.

METHODS

A literature review was conducted using PubMed on botulinum toxin treatment for scar formation, rosacea, and antiaging. Studies discussing the toxin mechanism of action and treatment algorithm were included. The authors also provided their personal experience in BoNT-A use for these 3 conditions.

RESULTS

The mechanism of action of Botulinum toxin A in improving scar formation, rosacea, and antiaging is now better understood. While it is effective in the short term, little is still known about how frequently treatment needs to be repeated and if there are any long-term effects.

CONCLUSION

While in vitro studies have supporting evidence on the mechanism of action of BoNT-A on scar formation, rosacea, and antiaging, further studies are needed to identify long-term treatment effects.

Botulinum toxin for cosmetic treatments in young adults: An evidence-based review and survey on current practice among aesthetic practitioners

BACKGROUND

Botulinum toxin A (BoNTA) treatments are popular worldwide. Young adults, less than 41 years of age, are an important cohort of patients seen in practice, and the optimal dosage of BoNTA in this age group remains poorly defined.

AIMS AND OBJECTIVE

To determine the optimal dosing of BoNTA across different age-matched cohorts by reviewing the literature and to evaluate current BoNTA practices among aesthetic practitioners when treating younger versus older adults.

METHODS

An evidence-based literature review was performed to evaluate the current evidence on BoNTA injections for cosmetic indications in millennials (born between 1981 and 1996) and young adults. A cross-sectional online survey was distributed to aesthetic practitioners to assess their current practice with BoNTA.

RESULTS

There is a paucity of high-quality research on BoNT in millennials. Our literature review suggests different patterns of practice when treating younger adults. Specifically, our survey revealed that: (1) younger adults are receiving, on average, fewer units of BoNTA at the glabella, forehead, and crow's feet, (2) younger toxin-naïve patients are also afraid to look frozen or unnatural, and (3) wrinkles prevention was the most common reason for seeking treatment in younger patients.

CONCLUSION

The literature review supports the efficacy of BoNTA for correcting wrinkles in millennials. Our findings provide further insight into the dosing pattern of cosmetic BoNTA and motivating factors for seeking treatments in young adults. This valuable information will help practitioners with treatment planning when seeing patients from different age cohorts. An individualized approach and a lower dosage of BoNTA in toxin-naïve younger adults are recommended.

Progressive Improvement in Static Glabellar Lines After Repeated Treatment With DaxibotulinumtoxinA for Injection

BACKGROUND

DaxibotulinumtoxinA for Injection (DAXI) is a novel botulinum toxin in development that has demonstrated efficacy on dynamic glabellar lines.

OBJECTIVE

To evaluate the effect of repeated DAXI treatment on static glabellar lines.

METHODS

This post hoc analysis included adults with moderate or severe dynamic glabellar lines who were treated with 40U DAXI in the SAKURA clinical program. Glabellar line severity was evaluated through validated subject and investigator scales.

RESULTS

Overall, 568 subjects received 3 DAXI treatments. Most subjects were White (92.3%) and female (85.7%). At baseline, 9.0% and 27.3% of subjects had no static glabellar lines based on subject and investigator assessment, respectively. Four weeks after DAXI Treatment Cycle 1, the proportion of subjects with no static glabellar lines increased to 57.9% and 64.8% based on subject and investigator assessment, respectively. At Week 4 after DAXI Treatment Cycles 2 and 3, the proportion further increased to 68.7% and 71.5%, respectively, based on subject assessment and 75.0% and 77.6% based on investigator assessment.

CONCLUSION

Subjects who received repeated DAXI treatment showed progressive improvement in their static glabellar lines. The extended duration of therapeutic benefit with DAXI on dynamic glabellar lines likely provides a long period of muscle inactivity/hypoactivity, during which dermal remodeling can occur.

Defining Skin Quality: Clinical Relevance, Terminology, and Assessment

BACKGROUND

Flawless skin is one of the most universally desired features, and demand for improvements in skin quality is growing rapidly. Skin quality has been shown to substantially impact emotional health, quality of life, self-perception, and interactions with others. Although skin quality improvements are a common end point in studies of cosmeceuticals, they are rarely assessed in clinical studies of other aesthetic treatments and products. Descriptive terminology for skin quality parameters also varies considerably within the aesthetic field, relying on a range of redundant and occasionally contradictory descriptors. In short, skin quality has not been clearly defined.

OBJECTIVE

The goal of this review is to highlight the importance of skin quality to patients and physicians, explore known and unknown factors comprising skin quality, and provide clarity regarding terminology, descriptors, and evaluation tools for assessing skin quality.

MATERIALS AND METHODS

A review of the literature on skin quality was performed without limitation on publication date. Relevant articles are presented.

RESULTS AND CONCLUSION

We propose a framework of attributes contributing to skin quality rooted in 3 fundamental categories-visible, mechanical, and topographical-with the aim to provide information to help guide clinicians and inform future clinical studies.

Efficacy and Safety of Prabotulinumtoxin A and Onabotulinumtoxin A for Crow's Feet: A Phase 3, Multicenter, Randomized, Double-Blind, Split-Face Study

BACKGROUND

Prabotulinumtoxin A has been shown to have efficacy for the treatment of upper-limb spasticity and improvement of moderate to severe glabellar lines. However, the efficacy and safety of prabotulinumtoxin A for crow's feet have not been evaluated.

OBJECTIVE

This study compared the efficacy and safety of prabotulinumtoxin A and onabotulinumtoxin A in the treatment of crow's feet.

PATIENTS AND METHODS

A multicenter, randomized, double-blind, active-controlled, split-face study was conducted in subjects with bilateral symmetric, moderate to severe crow's feet at maximum smile. The investigators assessed the severity of crow's feet by using the facial wrinkle scale, and the subjects reported the improvement in severity, their subjective satisfaction, and perceived age. The primary efficacy outcome was the proportion of subjects with Grade 0 or 1 severity of crow's feet at maximum smile at Week 4 as assessed by the investigators.

RESULTS

In the primary efficacy outcome assessment, there was no significant difference between the 2 groups (prabotulinumtoxin A, 65.02%; onabotulinumtoxin A, 62.56%; p = .0956). All secondary efficacy outcomes were also achieved. Adverse events related to injection were mild and recovered spontaneously.

CONCLUSION

Prabotulinumtoxin A and onabotulinumtoxin A have comparable efficacy and safety in the treatment of crow's feet.

Assessment of Pliability and Elasticity of the External Nasal Skin in Patients With Unilateral Nasal Valve Collapse: A Static Biomechanical Evaluation

Importance

Understanding the skin biomechanics, specifically pliability and elasticity, in patients with nasal valve collapse may allow for new methods to assess which patients require more advanced nasal valve surgery.

Objective

To test the hypothesis that in patients with unilateral nasal valve collapse, the side of the nose with the collapse will have lower elasticity and increased pliability compared with the normal side, as assessed by a blinded observer using the Cutometer MPA 580.

Design, Setting, and Participants

Prospective, investigator-blinded, case-control cohort study of patients with unilateral nasal valve collapse and subjective nasal obstruction conducted in an academic otolaryngology-head and neck surgery clinic.

Interventions

Patients were assessed using the Cutometer MPA 580 by a blinded assessor. Three measurements were performed bilaterally on the exterior skin of the nose corresponding to the level of the inferior edge of the upper lateral cartilage. Measurements taken at the skin inferior to the zygoma were used as a control.

Main Outcomes and Measures

Primary outcome measures of the nasal skin were pliability (Uf, defined as the lengthening of the skin after 3 seconds of constant load) and elasticity (Ua/Uf, defined as the percentage of the skin that returned to its normal position 3 seconds after the release from the 3-second constant load).

Results

Of the 27 patients included in the study, 15 (56%) were male, and 12 (44%) were female; mean (SD) age, 44 (21) years (range, 16-90 years). There was no difference between the measurements of the skin overlying the area of nasal valve collapse in elasticity: side without collapse (0.960% [0.031%]) vs side with collapse (0.967% [0.036%]) (mean difference, 0.007%; 95% CI, -0.018% to 0.021%) (P = .90). However, there was a significant difference in pliability: side of the nose without collapse (0.520 [0.139] mm) vs side with collapse (0.610 [0.200]) (mean difference, 0.090 mm; 95% CI, 0.014-0.156 mm) (P = .02).

Conclusions and Relevance

Although the skin in patients with nasal valve collapse appears to maintain its elasticity, it demonstrates an increased ability to stretch and lengthen compared with nasal skin of those without valve collapse. Future studies are required to determine whether the biomechanical changes are related to the length and severity of nasal obstruction, or whether these changes in the skin may help predict who will benefit from nasal valve surgery and whether these patients are at an increased risk of surgical failure.

Level of Evidence

2.

Preventive, Cumulative Effects of Botulinum Toxin Type A in Facial Aesthetics

BACKGROUND

Botulinum toxin Type A (BoNTA) is the gold standard for the treatment of dynamic rhytides in the face. Recently, clinical observation suggests that individuals who receive regular injections of BoNTA experience ongoing wrinkle reduction and improvements in overall skin quality not observed in those treated sporadically.

OBJECTIVE

To review scientific evidence of qualitative changes in the skin and the possibility of indirect or direct effects on fibroblasts affecting fibroblast activity, including collagen production, after repeated treatment with BoNTA.

MATERIALS AND METHODS

We examined the literature for supporting evidence of the effect of repeated treatment cycles on wrinkle reduction and skin quality; histological changes in collagen structure; alterations in biomechanical features of the skin; and potential fibroblastic response.

RESULTS

Apparent cumulative improvement on wrinkle reduction and additional skin quality attributes with regular BoNTA treatments suggests an ongoing process of dermal repair. Clinical observation suggests that BoNTA injections stimulate collagen production and lead to a reorganization of the collagen network within the extracellular matrix, which in turn may produce improvements in features associated with more youthful skin. Moreover, evidence suggests that BoNTA may have a direct or indirect effect on fibroblast activity.

CONCLUSION

Clinical observation of progressive wrinkle reduction and qualitative improvements in a number of skin attributes that accumulate with more frequent injections of BoNTA suggest an ongoing process of repair leading to prolonged and cumulative effects.

Global Aesthetics Consensus: Hyaluronic Acid Fillers and Botulinum Toxin Type A-Recommendations for Combined Treatment and Optimizing Outcomes in Diverse Patient Populations

BACKGROUND

Combination of fillers and botulinum toxin for aesthetic applications is increasingly popular. Patient demographics continue to diversify, and include an expanding population receiving maintenance treatments over decades.

METHODS

A multinational panel of plastic surgeons and dermatologists convened the Global Aesthetics Consensus Group to develop updated guidelines with a worldwide perspective for hyaluronic acid fillers and botulinum toxin. This publication considers strategies for combined treatments, and how patient diversity influences treatment planning and outcomes.

RESULTS

Global Aesthetics Consensus Group recommendations reflect increased use of combined treatments in the lower and upper face, and some midface regions. A fully patient-tailored approach considers physiologic and chronologic age, ethnically associated facial morphotypes, and aesthetic ideals based on sex and culture. Lower toxin dosing, to modulate rather than paralyze muscles, is indicated where volume deficits influence muscular activity. Combination of toxin with fillers is appropriate for several indications addressed previously with toxin alone. New scientific data regarding hyaluronic acid fillers foster an evidence-based approach to selection of products and injection techniques. Focus on aesthetic units, rather than isolated rhytides, optimizes results from toxin and fillers. It also informs longitudinal treatment planning, and analysis of toxin nonresponders.

CONCLUSIONS

The emerging objective of injectable treatment is facial harmonization rather than rejuvenation. Combined treatment is now a standard of care. Its use will increase further as we refine the concept that aspects of aging are intimately related, and that successful treatment entails identifying and addressing the primary causes of each.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, V.

Subject satisfaction with onabotulinumtoxinA treatment of glabellar and lateral canthal lines using a new patient-reported outcome measure

BACKGROUND

Patient satisfaction with treatment is an important outcome in facial aesthetic medicine.

OBJECTIVE

To evaluate subject satisfaction with onabotulinumtoxinA treatment of glabellar lines (GL) and crow's feet lines (CFL) using the validated Facial Line Satisfaction Questionnaire (FLSQ).

METHODS

In this randomized double-blind study, subjects with moderate/severe GL and CFL received onabotulinumtoxinA (20 U, GL; 24 U, CFL) or placebo. Over 120 days, the following were assessed: satisfaction, achievement of treatment expectations, satisfaction with duration of treatment (FLSQ), severity of GL and CFL (Facial Wrinkle Scale [FWS]), and aesthetic improvement (Global Aesthetic Improvement Scale).

RESULTS

Satisfaction in the per-protocol population was significantly greater at Day 60 in the onabotulinumtoxinA group (n = 60) compared with placebo (n = 57) for GL (81.7% vs 0%; p < .001). Most subjects treated with onabotulinumtoxinA remained satisfied up to 120 days. Achievement of treatment expectations (86.7%; Day 60), satisfaction (81.7%; Day 60), and satisfaction with the duration of treatment (61.6%; Day 90) were significantly better with onabotulinumtoxinA than placebo (p < .001) for GL and CFL combined. Efficacy (FWS) and aesthetic improvement were observed in most subjects at Days 30 and 60, respectively.

CONCLUSION

High satisfaction rates are achieved and sustained in subjects treated with onabotulinumtoxinA for GL and CFL combined.