Three-dimensional adipofascial and dermal structures involved in forehead crease formation

Deeply etched forehead creases indicate aging. Various treatments such as filler injections, fat grafting, and facelift surgery are used to remove them. However, knowledge of the anatomical structures associated with subcutaneous tissue changes and the superficial musculoaponeurotic system is lacking, and there is no consensus about the appropriate treatment. We have investigated the subcutaneous structures involved in forehead creases; this will help to establish selection criteria for improved treatment. The forehead sections of five unfixed adult Asian cadavers were obtained. Tissues containing forehead creases were removed from the periosteum and were examined using gross observation, radiography, histology, and nano-computed tomography. All methods revealed that the dermis in the skin crease area, namely the fold visible from the body surface, was bound to the frontalis muscle by a three-dimensional fibrous structure between the fatty septa. This structure was dense near the skin folds and sparse and thin in other areas. In particular, it was tightly bound to the dermis immediately below the crease, with collagen fibers traversing toward the epidermis. In addition, there were fewer skin appendages near the crease than in the normal area, or they were absent altogether; the epidermis was thicker, and the dermal papillae were more developed. It is thought that the density and firmness of the fibrous fatty septal structures between the dermis-frontalis muscle and the specific structures of the epidermis and dermis immediately below the crease account for the characteristic plastic forehead creases.

Treating Glabellar Lines With Botulinum Toxin: Does Your Patient Need to Frown Steadily?

BACKGROUND

The variable relationship between the orbicularis supercilii and frontalis muscles may cause side effects with botulin toxin; steadily frowning is the usual recommendation. Eliminating the need to frown until all injections are over might enhance efficacy and lessen the neurotoxicity risks related to muscle exhaustion.

OBJECTIVES

The goal of this study was to investigate whether the digital caliper-assessed distances between the medial and lateral corrugator injection sites and the midline differed significantly in patients persistently frowning from patients resting.

METHODS

Seventy-six individuals with glabellar wrinkles treated with botulinum toxin in the authors' private practices for glabellar lines voluntarily contributed their retrospective data about the positions of injection sites. The investigators had freely chosen to inject the medial and lateral sections of the corrugator supercilii during persistent maximum frown or at rest.

RESULTS

The mean differences in distances between the medial and lateral injection points and the estimated midline were clinically trivial (1.0 ± 1.28 and 1.5 ± 2.53 mm, respectively), although the distances between the relaxed and contracted medial and lateral injection sites exceeded 1.8 and 2.5 mm in 33.9% and 46.4% of patients, respectively. Distance differences, not significant before 40 years old, were statistically significant only for the lateral injections in older patients (on average, 1.9 ± 3.01 mm).

CONCLUSIONS

The average distances from the medial and lateral injection points and the midline appear minimally different in patients who frown until all injections are over and, conversely, patients who rest. Persistently frowning might be advisable only in patients older than 40. Facial asymmetries may be a confounding factor.

LEVEL OF EVIDENCE: 4

Estimating the Change in Facial Subunits During Positive and Negative Facial Expression Using Three-Dimensional Stereophotogrammetry Facial Analysis

Background: A more refined and clinically related facial expression analysis is required for patients who wish to be perceived more emotionally positive. Objective: To measure the change in skin vector and volume in facial subunits when expressing positive expression (happiness) compared with negative expressions (sadness, fear, disgust, and anger), using three-dimensional (3D) stereophotogrammetry analysis. Methods: This study took 3D photographs of 20 volunteers' face at rest and during positive and negative expression. The directions of skin vector and volume changes in each facial subregion were recorded and calculated. Results: In the positive expression, 78.3% (95% confidence interval [CI] 66.8-89.9) of the medial midfacial subregions presented superolateral vector and volume increase, whereas volume decrease in 82.5% (95% CI 78.5-86.5) of the lip subregions could be observed. In the negative expression, the vector changes were predominantly inferomedial in 26.0% (95% CI 15.4-36.5) of the forehead and 36.8% (95% CI 33.2-40.3) of the upper eyelid subregions, whereas volume increases in 34.0% (95% CI 30.4-37.7) of the upper eyelid subregions were observed. Conclusions: This 3D stereophotogrammetry analysis presents the morphological difference between the positive and negative expression.

Development and Validation of Facial Line Distress Scale for Forehead Lines: FINE-FL

BACKGROUND

Forehead lines (FL) are one of the main signs of aging. Traditional tools to measure FL have limited ability to evaluate the multidimensional impact of these lines on appearance, confidence, and psychological and social relationships.

OBJECTIVES

We developed and validated the Facial Line Distress Scale-Forehead Lines (FINE-FL) to evaluate the severity and psychosocial distress associated with FL.

METHODS

We conducted a cross-sectional survey for FINE-FL psychometric validation at a tertiary hospital and 2 local clinics in Korea. First, a preliminary item pool for the FINE-FL was developed through a qualitative interview based on literature reviews and expert consultations. Second, cognitive interviews and a pilot test were conducted to evaluate comprehension, ease of response, acceptability of terminology, phrasing, and response options. FINE-FL consisted of 26 items. In this study, exploratory factor analysis was conducted to identify the underlying factor structure of the FINE-FL, and internal consistency and test-retest reliability were also examined.

RESULTS

We found 21 items in 4 domains. The model fit was good. Coefficient αs ranged from 0.89 to 0.95 for subdomains and 0.96 for the total. The FINE-FL was moderately correlated with the appearance appraisal score. On the test-retest, the range of the intraclass correlation coefficient was 0.65 to 0.79.

CONCLUSIONS

FINE-FL is a reliable, valid, and comprehensive patient-reported outcome measure for assessing FL severity and distress. This will be helpful in determining a patient's eligibility for inclusion in a study and measuring primary or secondary effectiveness endpoints for forehead line treatment.

Assessment of preferable site for temperature measurement using non-contact infra-red temperature among pediatric patients

BACKGROUND

Accurate temperature measurement with little or no discomfort that is safe, without risk of hospital-acquired infections or perforations, is the preferred choice of medical professionals in pediatric settings. The objective was to discover the preferable site for body temperature measurement using non-contact infra-red thermometer (NCIT) among pediatric patients.

METHODS

NCIT measurement at mid forehead (F), right temporal region (T), right side of neck-over-carotid artery area (N), jugular notch (J), sternum (S), umbilical region and sublingual region (U) were compared with digital axillary temperature (DAT) in a single attempt in 500 patients, aged between 2 to 5 years with fever. Data was analyzed using Pearson's correlation, paired t-test and Bland-Altman plot to assess the correlation and agreement between the DAT and NCIT sites.

RESULTS

The mean temperature of NCIT-T (38.42±0.64 °C) was more agreeable with DAT (38.42±0.63 °C) compared to other body sites. The minimum mean bias of -0.00480 °C was noted for NCIT-F with 95% CI of -0.164-0.15; however, NCIT-F revealed many outliers as compared to NCIT-J. A strong positive correlation existed between DAT and NCIT sites (r value: 0.99-0.98). However, significant difference was found between DAT and NCIT-N, NCIT-F and NCIT-U (P<0.0001).

CONCLUSIONS

NCIT-J is the most preferable choice for measuring body temperature and can be interchanged with DAT. It will help to deliver fast results with enhanced patient comfort due to its non-invasive nature.

A Phase III Clinical Study of the Efficacy and Safety of Botulinum Toxin Type A (MASPORT) with DYSPORT for the Treatment of Glabellar Lines

BACKGROUND

Botulinum toxin type A is a widely used treatment of facial wrinkles. The objective of this study was to compare the efficacy and safety of a new botulinum toxin type A (Masport [abobotulinum toxin A], MasoonDarou Co) with DYSPORT® for the treatment of glabellar lines.

METHODS

262 subjects with moderate-to-severe glabellar lines received either a fixed dose of 50 units of MASPORT® or DYSPORT® (Ipsen Company, England). Subjects were followed up at 14, 30, 60, 90 and 120 days after injection. Efficacy was assessed by investigator at maximum frown and rest and also by Subject Global Assessment of Change (SGA). The responders were defined as persons with +2 grade improvement from baseline for both investigator and patient assessment. The occurrence and duration of adverse effects were recorded up throughout the study.

RESULTS

According to the investigator evaluations, the responder rate at maximum frown were 94.5% for MASPORT and 95.6% for DYSPORT group on day 30 and at rest were 85.45% and 85.68% for MASPORT and DYSPORT group, respectively. According to the subject self-assessment, the proportion of responders in MASPORT group at day 30 was 95.28% versus 97.04% for DYSPORT group. No serious drug related adverse effect was recorded in either study groups, and the rates of adverse effects were similar for both groups.

CONCLUSION

Abobotulinum toxin A [MASPORT] is equally safe and effective as commercial product [DYSPORT] for the treatment of glabellar lines with the dose of 50 units, up to 120 days.

LEVEL OF EVIDENCE I

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Predicting the evolution of clinical skin aging in a multi-ethnic population: Developing causal Bayesian networks using dermatological expertise

INTRODUCTION

Software to predict the impact of aging on physical appearance is increasingly popular. But it does not consider the complex interplay of factors that contribute to skin aging.

OBJECTIVES

To predict the +15-year progression of clinical signs of skin aging by developing Causal Bayesian Belief Networks (CBBNs) using expert knowledge from dermatologists.

MATERIAL AND METHODS

Structures and conditional probability distributions were elicited worldwide from dermatologists with experience of at least 15 years in aesthetics. CBBN models were built for all phototypes and for ages ranging from 18 to 65 years, focusing on wrinkles, pigmentary heterogeneity and facial ptosis. Models were also evaluated by a group of independent dermatologists ensuring the quality of prediction of the cumulative effects of extrinsic and intrinsic skin aging factors, especially the distribution of scores for clinical signs 15 years after the initial assessment.

RESULTS

For easiness, only models on African skins are presented in this paper. The forehead wrinkle evolution model has been detailed. Specific atlas and extrinsic factors of facial aging were used for this skin type. But the prediction method has been validated for all phototypes, and for all clinical signs of facial aging.

CONCLUSION

This method proposes a skin aging model that predicts the aging process for each clinical sign, considering endogenous and exogenous factors. It simulates aging curves according to lifestyle. It can be used as a preventive tool and could be coupled with a generative AI algorithm to visualize aging and, potentially, other skin conditions, using appropriate images.

Characteristic Dermatoscopic Features of Hyperpigmented Macules on the Faces of Young Children

The aim was to describe the characteristic dermatoscopic features of hyperpigmented macules on the faces of young children. Sixteen patients with typical clinical presentations of hyperpigmented macules on the faces of young children were included in this study. The lesions were evaluated using a dermatoscope. The clinical and dermatoscopic features were analyzed and summarized. There were 12 boys and 4 girls enrolled in the study. The hyperpigmented macules had an age of onset ranging from 1 to 18 months (mean, 6.12 months). The hyperpigmentation was distributed on the forehead and/or temple, as follows: forehead (n = 8 [50%]); temple (n = 3 [18.8%]); and both sites (n = 5 [31.2%]). Fifteen patients (93.7%) had pseudoreticular pigmentation, 1 patient (6.3%) had reticular pigment with pseudoreticular pigment, and 100% had erythema and linear/branching vessels. Light brown pseudoreticular pigment and linear vessels were shown to be the 2 major dermatoscopic manifestations of hyperpigmented macules on the faces of young children.

A cross-sectional study: correlation of forehead morphology and dentoskeletal malocclusion in Chinese people

BACKGROUND

The lateral profile is an important indicator of facial attractiveness. This study explored the general characteristics of the forehead profile and protrusion, and their relationship with related factors in structure and development.

METHODS

Four hundred fourteen Chinese participants in the Yangtze River Delta region were involved. Including 206 males (17.15 ± 7.68 years old) and 208 females (18.35 ± 8.06 years old); 94 children (8.54 ± 2.21 years old, ranging from 4 to 12 years old), 166 adolescents (14.83 ± 1.50 years old, ranging from 13 to 17 years old), and 154 adults (25.52 ± 4.89, 18 years or older). The frontal section of the forehead was used to explore its shape. The straight distance between the vertical line of the FH plane through the nasal root point and its parallel line, which is tangential to the forehead, indicates the forehead prominence. Frontal sinus width was measured using the method described by Mahmood.

RESULTS

The general shape of the forehead was straight and slightly bulged near the eyebrow arch in males but rounder in females. The average forehead protrusion in males was higher than that in females in adults. Significant differences in forehead protrusion between the dentoskeletal classifications and growth phases were notable. Frontal protrusion significantly correlated with frontal sinus depth, especially in males, adults, Class I, and those whose convex points were located in the lower section of the forehead.

CONCLUSIONS

Age, race, and sex affect the forehead protrusion and frontal sinus width. Forehead protrusion may be an indicator of dentoskeletal deformities in the early stage. And dentoskeletal deformities may impair the correlation between the frontal sinuses and forehead protrusion during development.

TRIAL REGISTRATION

This retrospective, cross-sectional study was reviewed and approved by the Research Ethical Committee (T2020008), and registered at ClinicalTrial.gov with an identified number (ChiCTR2100041913).

Self-perception of natural outcome, appearance, and emotional well-being after OnabotulinumtoxinA treatment for upper facial lines: Post hoc analysis across age and gender

BACKGROUND

OnabotulinumtoxinA (onabotA) is indicated for upper facial lines (UFL). Fear of unnatural-looking outcomes is a frequently reported treatment barrier.

AIMS

Examine patient-reported outcomes (PROs) after onabotA treatment for UFL.

METHODS

A post hoc analysis was conducted on two 12-month pivotal studies of onabotA for forehead and glabellar lines (20 U each), with/without treatment of crow's feet lines (±24 U). This analysis used PROs from the Facial Line Satisfaction Questionnaire: Items 4 (natural look), 5 (treatment effect), 11 (met expectations), and Impact Domain (appearance and psychological impact). The analysis included 458 neurotoxin-naive adults achieving a ≥2-grade improvement in forehead line (FHL) severity on the Facial Wrinkle Scale at Day 30 (primary endpoint). [Corrections made on 28 December 2023, after first online publication: 'UFL' in the previous sentence has been corrected to 'forehead line (FHL)' in this version.] Data were further stratified into millennials and men.

RESULTS

At Day 30, 90.5% of all participants, 94.6% of millennials, and 85.7% of men were satisfied with receiving a natural look. Millennials had higher odds of being satisfied with natural outcomes at Day 30. This measure remained > 80% for all groups throughout the 12 months. Additionally, ≥80% were satisfied with the treatment effect, and >90% reported results met expectations. At Day 30, ≥50% reported positive impacts on self-perceived appearance and psychological well-being, but millennials had higher, and men had lower odds of reporting these improvements.

CONCLUSIONS

Participants achieving a ≥2-grade improvement in FHL severity after onabotA reported high satisfaction with natural outcomes and the treatment effect, with improved self-perceived appearance and psychological well-being. [Corrections made on 28 December 2023, after first online publication: 'UFL' in the previous sentence has been corrected to 'FHL' in this version.] These results may help aesthetic providers and patients address fears regarding unnatural results with onabotA.

Facial Overfilled Syndrome

Facial overfilled syndrome is an underdiagnosed aesthetic complication due to multiple incorrect placements of fillers. Facial distortion due to the overfilled syndrome can be exaggerated by facial expressions and movements and worsens with tissue ptosis due to aging. Commonly "produced" by practitioners depending solely on fillers as a single modality for treatment, the overfilled syndrome can be seen among those who had volume overload in the midface, forehead, chin, and nose. Incorrectly placed dermal fillers, poor selection of filler products, overzealous attempts by the injectors, and overly enthusiastic clients who "chase the lines" are the common causes of this phenomenon.

Subunit Reconstruction With Local and Regional Flaps of a Total Cervicofacial Defect From Necrotizing Fasciitis

A 60-year-old woman with a ∼450 cm 2 right cervicofacial defect following successful treatment of necrotizing fasciitis was consulted for reconstruction. She had complete orbital, malar, buccal, labial, submental, and anterolateral neck skin and soft tissue defects and near complete defects of the forehead and nasal sidewall. She underwent reconstruction with a large 24 cm×11 cm supraclavicular, deltopectoral, forehead rotational, and labial advancement flaps with skin grafting of the orbit. Follow-up at 2 months demonstrated complete take of all flaps. The patient was satisfied with her appearance and considered her outcome favorable. She exhibited comparably premorbid speech and oral competence. Large defects of the head and neck require thorough surgical planning and consideration of a subunit reconstruction technique. While free tissue transfer provides a large area of healthy tissue from a suitable donor site, subunit reconstruction with local and regional flaps can provide a superior outcome in the correct patient.

Automatic Segmentation of Facial Regions of Interest and Stress Detection Using Machine Learning

Stress is a factor that affects many people today and is responsible for many of the causes of poor quality of life. For this reason, it is necessary to be able to determine whether a person is stressed or not. Therefore, it is necessary to develop tools that are non-invasive, innocuous, and easy to use. This paper describes a methodology for classifying stress in humans by automatically detecting facial regions of interest in thermal images using machine learning during a short Trier Social Stress Test. Five regions of interest, namely the nose, right cheek, left cheek, forehead, and chin, are automatically detected. The temperature of each of these regions is then extracted and used as input to a classifier, specifically a Support Vector Machine, which outputs three states: baseline, stressed, and relaxed. The proposal was developed and tested on thermal images of 25 participants who were subjected to a stress-inducing protocol followed by relaxation techniques. After testing the developed methodology, an accuracy of 95.4% and an error rate of 4.5% were obtained. The methodology proposed in this study allows the automatic classification of a person's stress state based on a thermal image of the face. This represents an innovative tool applicable to specialists. Furthermore, due to its robustness, it is also suitable for online applications.

Facial Aesthetic Ideals: A Literature Summary of Supporting Evidence

BACKGROUND

To achieve the goal of enhancing facial beauty it is crucial for aesthetic physicians and plastic surgeons to have a deep understanding of aesthetic ideals. Although numerous aesthetic criteria have been proposed over the years, there is a lack of empirical analysis supporting many of these standards.

OBJECTIVES

This aim of this review was to undertake the first exploration of the empirical evidence concerning the aesthetic ideals of the face in the existing literature.

METHODS

A comprehensive search in MEDLINE, Embase, Scopus and CENTRAL databases was conducted for primary clinical studies reporting on the classification of the facial aesthetic units as per the Gonzales-Ulloa facial aesthetic unit classification from January 1962 to November 2022.

RESULTS

A total of 36 articles were included in the final review: 12 case series, 14 cohort studies, and 10 comparative studies. These described the aesthetic ideals of the following areas: forehead (6 studies; mean level of evidence, 3.33); nose (9 studies; mean level of evidence, 3.6); orbit (6 studies; mean level of evidence, 3); cheek (4 studies; mean level of evidence, 4.07); lips (6 studies; mean level of evidence, 3.33); chin (4 studies; mean level of evidence, 3.75); ear (1 study; level of evidence, 4).

CONCLUSIONS

The units that were most extensively studied were the nose, forehead, and lip, and these studies also appeared in journals with higher impact factors than other subunits. Conversely, the chin and ear subunits had the fewest studies conducted on them and had lower impact factors. To provide a useful resource for readers, it would be prudent to identify and discuss influential papers for each subunit.

LEVEL OF EVIDENCE: 3

Impact of DaxibotulinumtoxinA for Injection on Brow Position and Frontalis Muscle Activity Following Treatment of Glabellar Lines

BACKGROUND

Botulinum toxin type A (BoNTA) injections for the treatment of facial lines may lead to pleasant or undesirable changes in eyebrow height and position.

OBJECTIVES

The aim of this study was to evaluate the impact of glabellar injection of DaxibotulinumtoxinA for Injection (DAXI), a novel BoNTA formulation, on eyebrow position and frontalis activity.

METHODS

This study involved the post hoc analysis of adult patients from the Phase 2a forehead lines (FHL, N = 60) and open-label safety (OLS, N = 175) studies who received a single dose of DAXI 40 U to the glabella and for whom facial photographs were taken at rest and at maximum eyebrow elevation. Median vertical and horizontal displacement of the brows and median forehead strain (an objective quantitative assessment of frontalis activity) from baseline to 2 weeks after glabellar DAXI injection were measured.

RESULTS

Two weeks after glabellar DAXI injection, vertical eyebrow movement (at rest) of the lateral brow was observed. In both studies, vertical movement was greatest in the lateral (0.6-0.9 mm) and mid (0.5-0.7 mm) brow regions; movement in the medial brow was negligible (0-0.23 mm). In both studies, a graded reduction in forehead strain was observed 2 weeks post glabellar DAXI injection, with the greatest reduction being in the lower segment (FHL, -73%; OLS, -82%). Treatment with DAXI showed improvements in FHL wrinkle severity.

CONCLUSIONS

Glabellar injection of DAXI showed a positive reduction in dynamic frontalis activity that maintained or had a positive effect on eyebrow position. Vertical movement of the brow was suggestive of an improved eyebrow shape with a mild lateral arch.

LEVEL OF EVIDENCE: 4

Integrative Assessment for Optimizing Aesthetic Outcomes When Treating Glabellar Lines With Botulinum Toxin Type A: An Appreciation of the Role of the Frontalis

Despite the perception that treatment of glabellar lines with botulinum toxin A is straightforward, the reality is that the glabellar region contains a number of interrelated muscles. To avoid adverse outcomes, practitioners need to appreciate how treatment of 1 facial muscle group influences the relative dominance of others. In particular, practitioners need to understand the independent role of the frontalis in eyebrow outcomes and the potential for negative outcomes if the lower frontalis is unintentionally weakened by botulinum toxin A treatment. In addition, practitioners must recognize how inter-individual variation in the depth, shape, and muscle fiber orientation among the upper facial muscles can affect outcomes. For optimal results, treatment of the glabellar complex requires a systematic and individualized approach based on anatomical principles of opposing muscle actions rather than a one-size-fits-all approach. This review provides the anatomical justification for the importance of an integrated assessment of the upper facial muscles and eyebrow position prior to glabellar treatment. In addition, a systematic and broad evaluation system is provided that can be employed by practitioners to more comprehensively assess the glabellar region in order to optimize outcomes and avoid negatively impacting resting brow position and dynamic brow movement.

LEVEL OF EVIDENCE: 5

Microwave Ablation for Refractory Giant Maxillofacial Arteriovenous Malformation: A Case Report

Maxillofacial arteriovenous malformation located in the sensitive parts of the nose and lips has been an arduous challenge for doctors to meet a balance between resection and aesthetics in one time. In this report, one patient with a giant arteriovenous malformation covering the forehead, the nose, the lip, and bilateral cheeks and resulting in the appearance of the face like a lion's face, can not meet satisfactory outcomes by other therapeutic methods. We successfully reduced the size of vascular lesion using low-power and short-duration microwave ablation under real-time ultrasound guidance. In the two-year follow-up, the patient's face almost recovered to normality. Microwave ablation is expected to be a new alternative therapy for the treatment of maxillofacial arteriovenous malformations. Laryngoscope, 133:2984-2987, 2023.

Effect of body mass index on soft tissues in adolescents with skeletal class I and normal facial height

Background

The evaluation of soft tissues in patients undergoing orthodontic treatment plays a critical role in diagnosis and treatment planning. This study aims to evaluate the effect of body mass index (BMI) on facial soft tissues in skeletal Class I patients with normal vertical growth.

Methods

The study included 72 patients with a normal vertical growth pattern (SN-GoGn 26-38°) and skeletal Class I (ANB 2‒4°) malocclusion. According to their BMI (kg/m2) values, the patients were divided into three groups of 24 individuals each: underweight (>5th percentile) (13 females, 11 males; mean age, 11.58 ± 1.95 years), normal weight (5‒85th percentile) (12 females, 12 males; mean age, 11.54 ± 1.95 years), overweight (85‒95th percentile) (12 females, 12 males; mean age, 11.62 ± 2.01 years). Soft tissue thickness and height measurements were made on lateral cephalometric radiographs.

Results

In all soft tissue thickness measurements, except for the nasion, the overweight weight group had higher values. In comparing the underweight and normal weight groups, statistically significant differences were found in the thickness measurements at the nasion and gnathion (p < 0.05). The differences in thickness measurements at the glabella, labiale superius, stomion, labiale inferius, pogonion, gnathion, and menton are statistically significant between the underweight and overweight groups (p < 0.005). Comparing the normal and overweight groups revealed statistically significant differences the thickness measurements at the glabella, labiale superius, stomion, pogonion and menton (p < 0.05).

SAMCEP Society consensus on the treatment of upper facial lines with botulinum neurotoxin type A: A tailored approach

BACKGROUND

The safety and efficacy of botulinum neurotoxin type A (BoNTA) treatments are well established, but injection techniques, target muscles, and toxin doses continue to evolve, with each refinement producing improvements in treatment outcomes. The recommendations in this consensus move away from standard templates and illustrate how to tailor treatments to individual patterns and strengths of muscle activity, and patient preferences.

METHODS

Seventeen experts in the fields of plastic surgery, dermatology, ophthalmology, otorhinolaryngology, and neurology convened in 2022 to develop consensus-based recommendations for the use of botulinum toxin A for the treatment of horizontal forehead lines, glabellar frown lines, and crow's feet lines that reflect current clinical practice. The focus was on how to tailor injections to individual patients to optimize treatment outcomes.

RESULTS

For each upper face indication, consensus members describe how to perform a dynamic assessment to optimize the dose and injection technique for each patient. A tailored treatment protocol is presented for commonly observed patterns of dynamic lines. Units of Inco are defined and the precise location of injection points, illustrated with the use of anatomical images.

CONCLUSION

This consensus provides up-to-date recommendations on the tailored treatment of upper facial lines based on the latest research and collective clinical experience of the expert injectors. Optimal outcomes require thorough patient evaluation, both at rest and during animation, using both visual and tactile cues; detailed understanding of facial muscular anatomy and how opposing muscles interact; and use of a BoNTA with high precision to target identified zones of excess muscle activity.

Positions of the Glabellar Arteries: Implications for Glabellar Injection

BACKGROUND

Glabellar filler injection is linked to an increased risk of blindness. A thorough understanding of vascular changes in the glabellar area is critical for safety. The study's goal was to precisely determine the three-dimensional placements of the arteries in the glabellar area.

METHODS

In 117 cadavers, the vascular structures in the glabellar area were examined. There were four segments (S1/S1'-S4/S4') and five points (P1-P5) specified. The number of identified arteries found in each section and at each position was tallied. Additionally, the depth of the underlying identified artery under each site was measured.

RESULTS

One to three named arteries per glabellar segment were found. Each segment had at least one named artery, and the number of named arteries detected between S1/S1' and S4/S4' decreased. The chance of encountering identified arteries at the 5 designated locations, P1-P5, was 7/117 (6.0%), 6/117 (5.1%), 7/117 (6.0%), 6/117 (5.1%), and 16/117 (13.7%), respectively. At P1-P5, the major artery trunk was 1.8 ± 0.3 mm, 1.6 ± 0.3 mm, 1.4 ± 0.2 mm, 1.3 ± 0.3 mm, and 1.1 ± 0.2 mm below the skin.

CONCLUSIONS

The site of the glabellar arteries was clearly shown in this investigation; these arteries were met at a rate of 14% from P1 to P5. We demonstrated that a single entry site through the glabella via cannula could readily keep the needle deep enough for safe glabellar filler injection.

LEVEL OF EVIDENCE V

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A Film Electrode upon Nanoarchitectonics of Bacterial Cellulose and Conductive Fabric for Forehead Electroencephalogram Measurement

In this paper, we present a soft and moisturizing film electrode based on bacterial cellulose and Ag/AgCl conductive cloth as a potential replacement for gel electrode patches in electroencephalogram (EEG) recording. The electrode materials are entirely flexible, and the bacterial cellulose membrane facilitates convenient adherence to the skin. EEG signals are transmitted from the skin to the bacterial cellulose first and then transferred to the Ag/AgCl conductive cloth connected to the amplifier. The water in the bacterial cellulose moisturizes the skin continuously, reducing the contact impedance to less than 10 kΩ, which is lower than commercial gel electrode patches. The contact impedance and equivalent circuits indicate that the bacterial cellulose electrode effectively reduces skin impedance. Moreover, the bacterial cellulose electrode exhibits lower noise than the gel electrode patch. The bacterial cellulose electrode has demonstrated success in collecting α rhythms. When recording EEG signals, the bacterial cellulose electrode and gel electrode have an average coherence of 0.86, indicating that they have similar performance across different EEG bands. Compared with current mainstream conductive rubber dry electrodes, gel electrodes, and conductive cloth electrodes, the bacterial cellulose electrode has obvious advantages in terms of contact impedance. The bacterial cellulose electrode does not cause skin discomfort after long-term recording, making it more suitable for applications with strict requirements for skin affinity than gel electrode patches.

Immunogenicity of DaxibotulinumtoxinA for Injection in Glabellar Lines

DaxibotulinumtoxinA-lanm for injection (DAXI), a novel botulinum toxin type A formulation, contains a purified 150-kD core neurotoxin (daxibotulinumtoxinA) and proprietary stabilizing peptide (RTP004), and is approved for glabellar line treatment. As with any biologic product, DAXI may potentially be immunogenic and elicit unwanted antibody formation, possibly resulting in partial or complete treatment failure. The immunogenicity of DAXI was assessed in 2 double-blind, placebo-controlled, single-dose studies and an open-label safety study of up to 3 repeat treatments. Of the 2737 evaluable patients, none developed neutralizing antibodies to daxibotulinumtoxinA and 0.8% developed treatment-related nonneutralizing anti-daxibotulinumtoxinA-binding antibodies. Of evaluable patients exposed to RTP004 with either DAXI or placebo, 1.3% developed treatment-related anti-RTP004-binding antibodies, which were mostly transient. No patient developed binding antibodies to both daxibotulinumtoxinA and RTP004. All patients with treatment-related binding antibodies to daxibotulinumtoxinA or RTP004 achieved a clinical response (none or mild glabellar line severity) at Week 4 following each DAXI treatment cycle. The duration of clinical response was not different between treatment cycles when antibodies were detected vs when they were absent. Although the analysis population was small compared to the number of patients likely to receive repeated treatment in clinical practice, these results suggest that DAXI administration at the approved glabellar lines dose has low immunogenic potential and that nonneutralizing antibodies to daxibotulinumtoxinA or RTP004 occur infrequently and often transiently, and have no impact on clinical efficacy, safety, or duration of action. Real-world data encompassing larger numbers of patients is needed to substantiate these results.

LEVEL OF EVIDENCE: 3

Bridging the Gap: Sustained Treatment Effect of Glabellar Lines With Twice-A-Year Treatment With DaxibotulinumtoxinA

BACKGROUND

To achieve natural-looking outcomes when treating dynamic lines with botulinum toxin (BoNT), retreatment must be timed such that the patient maintains a relatively constant aesthetic outcome. Although first-generation BoNT products require retreatment with 3- to 4-month frequency to avoid discontinuous correction, the average patient returns for treatment every 6 months, when these toxins have generally fully worn off.

OBJECTIVE

To discuss the number of days a typical patient treated with daxibotulinumtoxinA for injection (DAXI) or legacy BoNT products will spend undertreated or uncorrected in a given calendar year.

MATERIALS AND METHODS

Median time for maintaining glabellar lines in the "none" or "mild" severity range was compared for approved doses of onabotulinumtoxinA (ONA; 120 days) and DAXI (168 days).

RESULTS

The average patient treated with 40U of DAXI every 6 months can expect to be uncorrected (with "moderate" or "severe" glabellar lines) for 14.5 days between visits compared with 61.5 days for 20U of ONA.

CONCLUSION

An extended duration BoNT product can be expected to create greater consistency in aesthetic outcome and minimize the discontinuous correction commonly seen with first-generation BoNT products for patients treated twice a year, without requiring a change in patient behavior regarding visit frequency.

InfraNet: Accurate forehead temperature measurement framework for people in the wild with monocular thermal infrared camera

During an epidemic, accurate human temperature screening based on neural networks for disease surveillance is important and challenging. Existing distant human forehead temperature measuring device usually adopts a dual-camera system using paired RGB and thermal infrared images to conduct face detection and temperature measurement. Since the facial RGB image may undermine people's privacy, we designed a monocular thermal system and proposed an effective framework called the InfraNet to measure and calibrate forehead temperature of people in the wild. To address the challenge of temperature floating, the InfraNet calibrates the subject's temperature with one's physical depth and horizontal offset predicted by a single infrared image. Our InfraNet framework mainly consists of three parts: face detection subnet, depth and horizontal offset estimation subnet and temperature calibration subnet. The temperature calibration performance can be improved with the help of spatial regularization term concentrating on predicting precise depth and horizontal offset of people. Besides, we collected a large-scale infrared image dataset in the both lab and wild scenarios, including 8,215 thermal infrared images. Experiments on our wild dataset demonstrated that the InfraNet achieved 91.6% high accuracy of distant multi-subject temperature measurement on average under the standard temperature threshold of strict 0.3°C.

An optimal method for quantifying the facial sebum level and characterizing facial sebum features

BACKGROUND

Evidence suggests that sebum content is important in skin disorders such as acne. However, sebum levels change depending on the external environment, and quantifying skin sebum levels is challenging. Here, we propose an optimal method for quantifying the facial sebum level.

MATERIALS AND METHODS

Four hundred and sixty participants (160 males and 300 females) aged 20-40 were enrolled in this study. A Sebumeter SM 810 was used to measure the sebum level at five facial locations: the forehead, the chin, the left cheek, the right cheek, and the nose. The participants were divided into two groups; one group underwent a one-time measurement (n = 390, male: female = 120: 270), and the other underwent three consecutive measurements (n = 70, male: female = 40: 30). The casual sebum level (CSL) was measured in all patients after a 30-min acclimatization; subsequently, the sebum removal process was conducted, followed by a resting period of 1 h to determine the sebum excretion rate (SER). Spearman's correlation analysis and the Wilcoxon signed-rank test were used to compare the sebum level consistency and differences between the groups.

RESULTS

Although three consecutive measurements better reflected the sebum content, the one-time measurement also represented the relative sebum level. One hour after sebum removal, the sebum level recovered to 70%-90%; thus, this method was applicable for use in SER quantification. Of the five testing points, the sebum content was highest in the nose and lowest in the cheeks (both left and right). In addition, the cheeks were the most stable sites in terms of testing points, testing times, and CSL/SER values. A one-time measurement of the CSL could represent the SER 1 h after the sebum removal. In our cohort, the sebum level of males with oily skin was decreased at age 32-35, and that of males with non-oily skin increased at 28-35. The opposite trend was observed in female participants.

CONCLUSION

Sebum measurement methods were assessed, including testing times, indices (interval of time) and sites in a conditioned external environment. A one-time measurement of the CSL 1 h after sebum removal was sufficient to determine the sebum level and SER, and the cheeks are recommended as the testing site. Sex and skin type differences were observed in sebum level changes with age.

Advances in Electrode Materials for Scalp, Forehead, and Ear EEG: A Mini-Review

Electroencephalogram (EEG) records the electrical activity of neurons in the cerebral cortex and is used extensively to diagnose, treat, and monitor psychiatric and neurological conditions. Reliable contact between the skin and the electrodes is essential for achieving consistency and for obtaining electroencephalographic information. There has been an increasing demand for effective equipment and electrodes to overcome the time-consuming and cumbersome application of traditional systems. Recently, ear-centered EEG has met with growing interest since it can provide good signal quality due to the proximity of the ear to the brain. In addition, it can facilitate mobile and unobtrusive usage due to its smaller size and ease of use, since it can be used without interfering with the patient's daily activities. The purpose of this mini-review is to first introduce the broad range of electrodes used in conventional (scalp) EEG and subsequently discuss the state-of-the-art literature about around- and in-the-ear EEG.

Ultrasonographic analysis of facial skin thickness in relation to age, site, sex, and body mass index

BACKGROUND

Numerous nonsurgical but invasive cosmetic procedures are performed blindly in the dermis or subcutaneous fat layer of the facial skin.

OBJECTIVES

To measure the numerical skin thickness of the facial areas where dermatological procedures are performed by applying ultrasound techniques, and to make it possible to estimate the skin thickness by investigating the influence of several individual constitutional factors such as age, sex, and body mass index (BMI), so that these variables can be applied to estimate skin thickness.

MATERIALS AND METHODS

Skin thickness was measured at eight different facial points using an ultrasound machine (Affiniti 50; Philips Inc.). Demographic data were gathered using questionnaires. Manual BMI was calculated from the weight and height of each participant, and individual BMI measurements were performed using a body composition analyzer.

RESULTS

In terms of whole skin thickness, the thickest point was the mouth corner, and the thinnest point was the lateral forehead. The thickest point in the epidermis was the chin, and the thinnest point was the nasolabial fold. The thickest point in the dermis was the corner of the mouth, and the thinnest was the lateral forehead. Full skin thickness and dermal thickness were mostly lower in females. Skin thickness was not significantly correlated with BMI.

CONCLUSION

The skin thickness at different points on the face was variable, and realistic data about skin thickness can be obtained by in vivo ultrasonographic analysis of the skin.

Use of a novel indentometer to evaluate skin stiffness in healthy and diseased human skin

BACKGROUND

Mechanical behavior of the skin can be evaluated by different non-invasive methods. In this study, we applied a new measurement device based on indentometry to determine the skin mechanical properties in healthy individuals and in patients with systemic sclerosis (SSc).

MATERIAL AND METHODS

Three studies were performed. Study 1 included 100 healthy individuals (46 male and 54 female) divided into four age groups with mean ages of 21.5, 28.9, 51.2, and 69.3 years, respectively. Test sites were located on the center of the forehead and the middle of both volar forearms. Study 2 included 16 healthy individuals (two males and 14 females). Test sites were on both volar forearms. Measurements were made before and after the application of Vaseline and emulsion with 12% urea. Study 3 included 20 patients (one male and 19 females) with SSc and 60 age-matched healthy individuals (23 males and 37 females). Test sites were on the center of the forehead and the middle of both volar forearms. Skin stiffness was measured with skin Indentometer IDM 800 (Courage + Khazaka, Cologne, Germany) equipped with two probes with pin diameters of 3 and 5 mm, respectively. The stiffer the skin, the less deep the displacement by the indenter. The smaller the diameter, the deeper the pin will go into the skin when using the same force. In addition, the Corneometer CM 820 (Courage + Khazaka) was used to determine epidermal water content in study 2.

RESULTS

Indentometric (IDM) values of healthy subjects measured with both probes were lower on the forehead compared to volar forearms. There was no significant difference between both forearms. In all age groups, the IDM values on the male forearms were lower than on the female forearms whereas there was no significant difference on the forehead. In both sex and on all test locations a significant positive correlation between age and IDM values measured with both probes was observed. There was a significant positive correlation between IDM values measured with both probes. The application of moisturizers induced significant changes in epidermal water content whereas the IDM values remained unchanged. At both the forehead and volar forearms, the IDM values in patients with SSc were significantly lower compared to the healthy control skin.

CONCLUSION

The non-invasive indentometric method used can successfully distinguish the changes in normal skin mechanical properties related to age, sex, and anatomical location, as well as in patients with SSc. The method is not appropriate to study the changes related to epidermal hydration.

Spatial summation of thermal sensitivity is limited to small areas: Comparisons of the forehead, forearm, abdomen, and foot

The purpose of the present study was to examine if spatial summation in thermal sensitivity exists when stimulating areas larger than about 1% of body surface area (BSA) (approximately 200 cm2). We hypothesized that spatial summation would exist within a limited area and the effect would be insignificant for over the 1%BSA. Fifteen young males participated in this study and we measured their warmth and hot sensation thresholds on the four body regions (the forehead, forearm, abdomen, and instep) using the three sizes of radiant film heaters (10 × 10, 15 × 15, and 20 × 20 cm2 heating film area). The heating panel was kept at a distance of 10 cm from the skin and the surface temperature of the heating panel increased by 1 °C·s-1. The results showed that warmth and hot sensation thresholds were higher for the 100 cm2 condition than the 225 or 400 cm2 conditions (P < 0.05), but no differences were found between the 225 and 400 cm2 conditions. Secondly, the instep was most insensitive to the gradual increase of radiant heat among the four body regions for all three stimulating film sizes, even though the hot threshold was lowest for the instep because the initial foot temperature was lower than other skin temperatures. In summary, spatial summation in thermal sensitivity was found for the 100 and 225 cm 2 conditions, but not for the 225 and 400 cm2 conditions. These results suggest that spatial summation exists but limited to small stimulating areas, smaller than approximately 1% BSA.

Investigation of post mortem brain, rectal and forehead temperature relations

It is well known that magnetic resonance (MR) imaging is temperature sensitive, which is highly relevant for post mortem examinations. Therefore, the determination of the exact temperature of the investigated body site, e.g. the brain, is crucial. However, direct temperature measurements are invasive and inconvenient. Thus, in view of post mortem MR imaging of the brain, this study aims at investigating the relation between the brain and the forehead temperature for modelling the brain temperature based on the non-invasive forehead temperature. In addition, the brain temperature will be compared to the rectal temperature. Brain temperature profiles measured in the longitudinal fissure between the brain hemispheres, as well as rectal and forehead temperature profiles of 16 deceased were acquired continuously. Linear mixed, linear, quadratic and cubic models were fitted to the relation between the longitudinal fissure and the forehead and between the longitudinal fissure and the rectal temperature, respectively. Highest adjusted R2 values were found between the longitudinal fissure and the forehead temperature, as well as between the longitudinal fissure and the rectal temperature using a linear mixed model including the sex, environmental temperature and humidity as fixed effects. The results indicate that the forehead, as well as the rectal temperature, can be used to model the brain temperature measured in the longitudinal fissure. Comparable fit results were observed for the longitudinal fissure-forehead temperature relation and for the longitudinal fissure-rectal temperature relation. Combined with the fact that the forehead temperature overcomes the problem of measurement invasiveness, the results suggest using the forehead temperature for modelling the brain temperature in the longitudinal fissure.

A 9-year-old boy with a nonmalignant forehead tumor - a rare case of pediatric Pott's puffy tumor

BACKGROUND

Pott's puffy tumor (PPT) is a rare and potentially deadly complication of frontal sinusitis consisting of subperiosteal abscess and osteomyelitis of the frontal bone.

CASE PRESENTATION

We report the case of a 9-year-old boy who presented with fever and soft tissue swelling of the forehead. Magnetic resonance imaging (MRI) depicted an abscess in the subcutaneous tissue frontally and an epidural empyema, while a cranial computed tomography (CT) scan revealed bone erosion as a sign of osteomyelitis. The patient was treated accordingly.

CONCLUSIONS

This rare condition is essential to keep in mind as it needs a multidisciplinary approach and relevant imaging to start proper treatment and thus decrease the risk of intracranial complications.

Patient compliance and satisfaction with a new forehead device for positional obstructive sleep apnoea treatment: a post hoc analysis of a randomised controlled trial

BACKGROUND

The influence of body position in obstructive sleep apnoea patients is well known. A positional therapy device placed at the forehead has proven to be effective in reducing the severity of positional obstructive sleep apnoea (POSA) symptoms. The aim of the study was to evaluate patients' therapy compliance and satisfaction in the short term and mid-term.

METHODS

A post hoc analysis of a randomised controlled trial was conducted using an inactive device (ID) or an active device (AD) for 3 months. The primary outcomes were device usage and the percentage of patients with good compliance (defined as device use for more than 4 hours per night and more than 70% of nights per week). Secondary outcomes included time spent with head in the supine position, patient satisfaction and side effects.

RESULTS

The median duration of using the device was 6.9 hours in the ID group and 6.7 hours in the AD group (p=0.309), and the durations were similar throughout the follow-up period and from the first day of use. The percentage of patients with good compliance was similar and greater than 60% in both groups. The median time spent with head in the supine position was significantly lower in the AD group (2.9%) than in the ID group (12.4%) since the first day of treatment. Both groups showed satisfaction scores values above 8.5 (out of 10) in all items, while side effects were scarcely reported.

CONCLUSION

High device compliance was achieved in POSA patients, both in terms of device usage time and percentage of days used. Patients were highly satisfied, and the device effectively reduced the time spent with the head in the supine position from the first day of use.

Validation of a wearable forehead sleep recorder against polysomnography in sleep staging and desaturation events in a clinical sample

STUDY OBJECTIVES

Wearable sleep recording devices may be a helpful alternative method for polysomnography (PSG) due to their higher accessibility and comfort as well as lower cost, but their validities need to be examined. The aim of this study was to evaluate the accuracy of a novel single-channel, electroencephalography-based wearable forehead sleep recorder (UMindSleep) to assess sleep staging and oxygen desaturation.

METHODS

Two hundred and three Chinese adults recruited from a sleep medicine center underwent an overnight study wearing UMindSleep and PSG simultaneously. Sleep parameters including sleep staging and oxygen desaturation index were compared between UMindSleep and PSG.

RESULTS

A total of 195,349 valid epochs from 197 participants (171 with obstructive sleep apnea, 86.8%) were included in analyses of sleep staging. Sensitivities of UMindSleep compared to PSG were 79.7% for wake, 85.8% for light sleep, 79.4% for deep sleep, and 82.7% for rapid eye movement sleep. Specificities were 95.3% for wake, 83.4% for light sleep, 97.0% for deep sleep, and 96.8% for rapid eye movement sleep. Furthermore, the kappa agreements of 0.69-0.79 were indicative of a substantial agreement for sleep staging between UMindSleep and PSG. Sensitivity and specificity regarding oxygen desaturation index were 93.4% and 88.9%, yielding a kappa coefficient of 0.82.

CONCLUSIONS

Our findings suggest that UMindSleep may serve as a feasible, accurate, and dependable device for screening of sleep disorders (eg, obstructive sleep apnea) and assessing sleep structure.

CITATION

Chen X, Jin X, Zhang J, Ho KW, Wei Y, Cheng H. Validation of a wearable forehead sleep recorder against polysomnography in sleep staging and desaturation events in a clinical sample. J Clin Sleep Med. 2023;19(4):711-718.

Exploring regional aspects of 3D facial variation within European individuals

Facial ancestry can be described as variation that exists in facial features that are shared amongst members of a population due to environmental and genetic effects. Even within Europe, faces vary among subregions and may lead to confounding in genetic association studies if unaccounted for. Genetic studies use genetic principal components (PCs) to describe facial ancestry to circumvent this issue. Yet the phenotypic effect of these genetic PCs on the face has yet to be described, and phenotype-based alternatives compared. In anthropological studies, consensus faces are utilized as they depict a phenotypic, not genetic, ancestry effect. In this study, we explored the effects of regional differences on facial ancestry in 744 Europeans using genetic and anthropological approaches. Both showed similar ancestry effects between subgroups, localized mainly to the forehead, nose, and chin. Consensus faces explained the variation seen in only the first three genetic PCs, differing more in magnitude than shape change. Here we show only minor differences between the two methods and discuss a combined approach as a possible alternative for facial scan correction that is less cohort dependent, more replicable, non-linear, and can be made open access for use across research groups, enhancing future studies in this field.

Accuracy of low-cost alternative facial scanners: a prospective cohort study

INTRODUCTION

Three-dimensional facial scans have recently begun to play an increasingly important role in the peri-therapeutic management of oral and maxillofacial and head and neck surgery cases. Face scan images can be generated by optical facial scanners utilizing line-laser, stereophotography, or structured light modalities, as well as from volumetric data: for example, from cone beam computed tomography (CBCT). This study aimed to evaluate whether two low-cost procedures for the creation of three-dimensional face scan images were capable of producing sufficiently accurate data sets for clinical analysis.

MATERIALS AND METHODS

Fifty healthy volunteers were included in the study. Two test objects with defined dimensions (Lego bricks) were attached to the forehead and the left cheek of each volunteer. Facial anthropometric values (i.e., the distances between the medial canthi, the lateral canthi, the nasal alae, and the angles of the mouth) were first measured manually. Subsequently, face scans were performed with a smart device and manual photogrammetry and the values obtained were compared with the manually measured data sets.

RESULTS

The anthropometric distances deviated, on average, 2.17 mm from the manual measurements (smart device scanning deviation 3.01 mm, photogrammetry deviation 1.34 mm), with seven out of eight deviations being statistically significant. For the Lego brick, from a total of 32 angles, 19 values demonstrated a significant difference from the original 90° angles. The average deviation was 6.5° (smart device scanning deviation 10.1°, photogrammetry deviation 2.8°).

CONCLUSION

Manual photogrammetry demonstrated greater accuracy when creating three-dimensional face scan images; however, smart devices are more user-friendly. Dental professionals should monitor camera and smart device technical improvements carefully when choosing and adequate technique for 3D scanning.

Efficacy and Safety of AbobotulinumtoxinA for the Treatment of Glabellar Lines in Chinese Patients: A Pivotal, Phase 3, Randomized, Double-Blind and Open-Label Phase Study

BACKGROUND

Various botulinumtoxinA formulations are approved for glabellar lines treatment worldwide, including abobotulinumtoxinA (Dysport^®).

OBJECTIVES

Assess abobotulinumtoxinA superiority versus placebo and non-inferiority versus active comparator (onabotulinumtoxinA; Botox^®), for the treatment of Chinese patients with moderate/severe glabellar lines.

METHODS

Phase 3, randomized study (NCT02450526) comprising a double-blind (cycle 1) phase and an open-label (cycles 2-5) phase. Patients received abobotulinumtoxinA 50 units or matching placebo (5:1), active comparator (onabotulinumtoxinA 20 units) or matching placebo (5:1). In cycles 2-5, eligible patients were retreated with abobotulinumtoxinA only. Responders had glabellar lines of none/mild severity.

PRIMARY ENDPOINT

responder rates at cycle 1, day 29 at maximum frown with abobotulinumtoxinA versus placebo (for superiority; by investigator's live assessment [ILA] and subject's self-assessment [SSA]), and versus active comparator (for non-inferiority; by ILA). Treatment-emergent adverse events were recorded.

RESULTS

Overall, 520 patients were randomized. Superiority and non-inferiority, respectively, were demonstrated for abobotulinumtoxinA versus placebo (ILA, SSA; both p < 0.0001) and abobotulinumtoxinA versus active comparator. AbobotulinumtoxinA efficacy was maintained over open-label cycles; median time to onset of efficacy was 2.0 days. After 6 months, 17% of patients treated with abobotulinumtoxinA remained responders. AbobotulinumtoxinA was well-tolerated. Safety results were in line with the known profile of abobotulinumtoxinA; adverse events rate decreased with repeated treatment.

CONCLUSIONS

After a single injection, abobotulinumtoxinA demonstrated superiority versus placebo and non-inferiority versus onabotulinumtoxinA for the treatment of moderate-to-severe glabellar lines in Chinese patients. Multiple injections of abobotulinumtoxinA demonstrated efficacy and safety in the treatment of glabellar lines in Chinese patients.

LEVEL OF EVIDENCE I

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .