Understanding clinical meaningfulness when targeting the depressor anguli oris muscle (DAO) with neuromodulators: a clinical prospective interventional study.

BACKGROUND: Neuromodulator injections in the US increased by 24% from 2021 to 2022. This rise is attributed to new products and growing acceptance of minimally invasive aesthetic treatments. Recent studies emphasize the importance of facial anatomy for precision and, consequently, a higher efficacy of neuromodulator treatments. This study aims to evaluate the clinical efficacy of a novel previously proposed injection technique targeting the depressor anguli oris (DAO) muscle to improve oral commissure position. This clinical, prospective study included 34 volunteers from the Shinobu Clinic, São Paulo, Brazil. Patients received 3 units of onabotulinumtoxinA per side, injected mid-distance between the oral commissure and jawline, following the labiomandibular sulcus (LMS). Standardized photographs and assessments using the Oral Commissure Severity Scale (OCSS) and Global Aesthetic Improvement Scale (GAIS) were conducted before and 30 days post-treatment. Statistical analyses included t-tests, Wilcoxon Signed Rank test, and generalized linear models. The average increase in commissural height was 5.22% (p < 0.001). OCSS ratings improved significantly from baseline (clinician: 1.21 to 0.72, p < 0.001; patient: 0.93 to 0.69, p < 0.001). However, GAIS scores indicated no significant change (patient: 0.32, observer: 0.38; p = 0.491). The proposed injection technique improves perioral aesthetics objectively and subjectively. However, the lack of significant change in GAIS scores suggests that perceived improvements may not be clinically meaningful to patients. Future studies should focus on patient-centered evaluation methods to better assess aesthetic outcomes.

Reticulated livedoid skin patterns after soft-tissue filler-related vascular adverse events.

BACKGROUND: For the treatment of vascular adverse events caused by filler injections, duplex ultrasound imaging may be used. The findings of duplex ultrasound examination and the clinical features of reticulated livedoid skin patterns were compared with the hemifaces anatomy. OBJECTIVE: The objective of this study was to link the reticulated livedoid skin patterns to the corresponding duplex ultrasound findings and the facial perforasomes. METHODS: Duplex ultrasound imaging was used for the diagnosis and treatment of vascular adverse events. The clinical features and duplex ultrasound findings of 125 patients were investigated. Six cadaver hemifaces were examined to compare the typical livedo skin patterns with the vasculature of the face. RESULTS: Clinically, the affected skin showed a similar reticulated pattern in each facial area corresponding with arterial anatomy and their perforators in the cadaver hemifaces. With duplex ultrasound, a disturbed microvascularization in the superficial fatty layer was visualized. After hyaluronidase injection, clinical improvement of the skin pattern was seen. Normalization of blood flow was noted accompanied by restoration of flow in the corresponding perforator artery. The skin patterns could be linked to the perforators of the superficial fat compartments. CONCLUSION: The livedo skin patterns seen in vascular adverse events may reflect the involvement of the perforators.

Intracorporeal evaluation of hyaluronic acid fillers with varied rheological properties and correlations with aesthetic outcomes.

BACKGROUND: Understanding the differences in soft tissue filler rheology and how these properties can impact clinical results is a fundamental concepts for any injector. This study aimed to assess the tissue integration characteristics of hyaluronic acid (HA) fillers manufactured with different technologies (Non-Animal Stabilized HA [HA-N] or Optimal Balance Technology [HA-O]) using ultra-high-frequency ultrasound. METHODS: Twelve female participants with mild-to-moderate midface volume loss and temporal hollowing were enrolled and treated with HA-N and/or HA-O. Participants were seen at five visits (screening/baseline [treatment], and Weeks 1 [optional touch-up], 4, 6, and 8 [follow-up visits]). Ultrasound was used to evaluate the degree of product integration. RESULTS: On ultrasound, HA-N presented with distinct borders, minimal tissue integration, and a capacity to displace tissues. Conversely, HA-O tended to spread horizontally within the same tissue plane and integrated within tissues. The volumizing capacity of the HA-O fillers was dependent on particle size. CONCLUSION: HA-N is suited for deep injections in areas such as the upper lateral cheek and under the muscle of the temporal region when a lifting effect is desired; HA-O is best suited for subcutaneous injections, in areas of dynamic movement or for patients with thin skin; and can be injected subcutaneously or supraperiosteally when a volumizing effect is desired.

Post-Treatment Displacement of Facial Soft Tissue Fillers-A Retrospective Ultrasound-based Investigation of 382 Zygomatic Regions.

BACKGROUND: Clinical and ultrasound experience has revealed that after soft tissue injections of the lateral cheek, the filler may displace from the zygoma to the caudal temporal area. OBJECTIVE: To obtain more data to provide insight into product distribution when soft tissue fillers are injected in the zygomatic region. METHODS: Two hundred patients were examined with facial ultrasound imaging of the zygomatic and temporal region. Inclusion criteria were simply a positive response on the screening questionnaire as to whether or not they had filler injections placed in their lateral cheek. Control injections were also performed to the zygomatic regions of a body donor and in 10 patients ultrasound-guided. RESULTS: A correlation was found between the layers in which filler was detected on the zygoma and where it was ultimately found in the temples. Four different redistribution patterns were observed: (1) migration of filler within the superficial muscular aponeurotic system (SMAS) on the zygoma into the superficial temporal fascia. Migration of filler from the lateral suborbicularis oculi fat to (2) the deep interfacial plane of the temple or (3) to the superficial temporal fat pad; (4) migration from the supraperiosteal layer of the zygoma to the superficial temporal fat pad. Body donor and patients: filler deposits injected on the zygoma were witnessed to shift during injection into the caudal part of the temple. CONCLUSION: Soft tissue filler aliquots may be redistributed into the temples after injections of the lateral side of the zygomatic arch. The displacement follows a distinct pattern depending on the initial layer of injection.

Investigating Facial Muscle Physiology Following Soft Tissue Filler Injections-A Surface-derived Electromyographic and Skin Vector Displacement Analytic Study.

The use of hyaluronic acid-based soft tissue fillers has often been reported to modulate the muscle, that is, to cause myomodulation. To our knowledge, there has been so far no scientific study investigating the potential of hyaluronic acid-based soft tissue fillers to modulate or actually alter the function of facial muscles. To further assess this three-dimensional (3D) surface imaging and electromyography (EMG)-based prospective study investigated the changes of facial muscle contraction after injection of strategically placed hyaluronic acid-based soft tissue fillers to assess the actual validity of the term myomodulation. A total of 13 subjects with a mean age of 37.8 years (12 females, 1 male) were injected according to a predefined injection protocol. Surface EMG and 3D surface imaging were performed prior to the injection and 5 days after the injection. The results showed no significant change in the strength of the muscles (measured in µV) after injection of hyaluronic acid-based soft tissue fillers. However, horizontal and vertical skin displacement upon contraction of the zygomaticus major muscle changed significantly between baseline and follow-up, with a mean horizontal skin displacement increase from 3.2 to 4.1 mm. Upon contraction of the depressor anguli oris muscle, the horizontal skin displacement did not change significantly (2.15 vs. 2.05 mm), while vertical skin displacement increased significantly from 2.9 to 4.3 mm. The modification of the surrounding tissue caused an alteration of the vectorial skin displacement upon contraction of the muscle. A potential explanation could be the increased distance between the origin and insertion of the muscle due to the material deposition in the proximity of the relevant facial muscles, leading to a change of contraction vector.

Comparative Trial Evaluating a High- Versus Low-Integration Hyaluronic Acid Filler for Contouring the Jawline.

BACKGROUND: Contour deficits of the jawline are an area of concern for many aesthetic patients. While the use of hyaluronic acid (HA) for jawline enhancement has been described previously, comparative investigations of HA fillers manufactured with different technologies are limited. Therefore, the aim of the current investigation was to evaluate the safety and efficacy of Restylane Lyft (HA-L) and Restylane Defyne (HA-D) for contouring of the jawline. METHODS: This prospective clinical trial enrolled forty (40) participants. Twenty (20) participants with thin skin were treated with HA-D, and twenty (20) participants with thick skin were treated with HA-L. Visits occurred at Screening/Baseline (treatment), Week 2 (touch-up), and Months 1, 3, and 6. At each visit, a blinded evaluator rated 3-dimensional participant imagery according to the Jawline Volume Loss Scale and participants completed the Jawline Subject Satisfaction Scale. Frequency of treatment-emergent adverse events was collected via participant diaries, and product integration characteristics were evaluated via ultrasound. RESULTS: Chi-square tests of independence revealed statistically significant improvements in severities of jawline volume loss, which were maximal at Month 1 (100%) and maintained until Month 6 (82.05%). At Month 1, 92.10% of participants reported being satisfied with overall treatment effects. Adverse events were expected per the product monographs and did not vary per group. On ultrasound, HA-L displayed targeted product integration and HA-D displayed diffuse product integration. CONCLUSIONS: Results support the use of HA-L and HA-D for the contouring of the jawline with each product capable of providing distinct advantages depending on patient attributes (e.g., skin thickness, underlying bone structure, desired outcomes). LEVEL III: Evidence obtained from well-designed cohort or case-control analytic studies. LEVEL OF EVIDENCE III: 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 .

The Influence of Scar Patterns After Reduction Mammoplasty on Eye Movement and Gaze Pattern: An Eye-Tracking Investigation.

BACKGROUND: Given that scars are acknowledged as the primary cause of postoperative dissatisfaction following reduction mammoplasty, it is imperative to comprehend the patient's visual perception of different scar patterns in order to enhance patient satisfaction. To achieve this, eye-tracking technology provides an unbiased method of evaluating how observers assess breast scars. METHODS: 58 participants (32 females and 26 males) between the ages of 19 and 82 years (mean age of 29.47 ± 10.98 years) were shown 18 color photographs, taken at 3 viewing angles (right 45° oblique, frontal and frontal view with arms raised), from 6 patients undergone reduction mammoplasty with the inverted T-scar technique (3 patients) or no-vertical-scar technique (3 patients). The images were presented to every participant for a fixed duration of 5 s each. Eye-tracking device was used to collect and analyze the gaze data of viewers. RESULTS: The nipple-areola complex (NAC) and the periareolar scar captured observers' gaze faster, had longer duration and more count of eye fixation than all other parts of breast scars, regardless of the viewing angle and scar pattern. Moreover, the scar region in the inverted T-scar pattern received greater and faster visual attraction of observer's gaze than the no-vertical-scar pattern. CONCLUSION: The NAC and the periareolar scar seem to be perceived as the most important regions for breast aesthetics. The findings can be helpful to assist plastic surgeons in determining the most appropriate technique for reduction mammoplasty, meanwhile underlining the importance of a fine periareolar scar and symmetric NAC for excellent aesthetic outcomes. This is to our best knowledge the first study using eye-tracking technology in evaluating reduction mammoplasty outcomes. This study explored the influence of different scar patterns after reduction mammoplasty on eye movements and gaze patterns among observers. The study have validated the significance of the NAC and the periareolar scar for breast aesthetics and revealed that the scar region in the inverted T-scar pattern may be judged less visually attractive than the no-vertical-scar pattern. 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 .

Understanding the Interplay Between Skin, Fascia, and Muscles of the Midface in Facial Aging.

BACKGROUND: Surgical, minimally-invasive, and non-invasive aesthetic procedures try to ameliorate the signs of facial aging, but also focus on enhancing various individual features of beauty in each patient. Herein, the midface plays a central role due to its location but also its importance for the aesthetic perception and facial expression. OBJECTIVE: To date, no study has investigated the interplay between facial muscles and its connecting subdermal architecture during facial aging to provide a more comprehensive understanding of the middle face. MATERIALS AND METHODS: A total of 76 subjects, consisting of 30 males (39.5%) and 46 females (60.5%) with a mean age of 42.2 (18.7) years [range 19-80] and a mean BMI of 24.6 (3.7) kg/m2 [range 18-35], were enrolled in this investigation. Cutometry (skin aging), 3D skin displacement analyses (subdermal connective tissue aging), and sEMG (muscle aging) analyses were utilized. RESULTS: The results revealed that overall skin firmness increased, and skin elasticity decreased (p < 0.001), sEMG signal of the investigated muscles decreased (p < 0.001), whereas midfacial mobility remained unaltered (p = 0.722). CONCLUSION: The results of this study indicate that midfacial aging is a measurable effect when utilizing individual measurement modalities for assessing skin, subdermal fascia, and midfacial muscles. The function of midfacial muscles revealed a potential threshold effect, which is not reached during midfacial aging due to the unchanged soft tissue mobility at older age. However, to understand its clinical presentation all midfacial soft tissues need to be factored in and a holistic picture needs to be created. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes review articles, book reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. 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 .

Investigating the Contraction Pattern of the Zygomaticus Major Muscle and its Clinical Relevance: A Functional MRI Study.

BACKGROUND: Our understanding of facial anatomy has significantly evolved, yet the detailed contraction patterns of facial muscles and their presentation during clinical imaging remain largely unexplored. Understanding the contraction patterns and visual presentation of these muscles, particularly the zygomaticus major could enhance pre-surgical facial assessments and the development of new treatment strategies. METHODS: A total of 34 healthy young individuals (17 female, 17 male) with a mean age of 23.6 (2.4) years [range: 20-30] were investigated regarding the length, thickness, width, and angle of the zygomaticus major muscle in five different facial expressions (i.e., repose, anger, joy, surprise, and sadness) utilizing MR imaging. RESULTS: Joyful expressions caused a reduction in muscle length to 85.6% of its original length and an increase in width (103.4%), thickness (108.4%), and facial angle (2.72°) when compared to that in repose, suggesting isotonic contraction. Conversely, expressions of anger, surprise, and sadness generally led to muscle stretching, seen through changes in length (98.9%, 104.3%, and 102.7%, respectively), width (98.8%, 96.5%, and 99.4%, respectively), and thickness (91.2%, 91.0%, and 102.7%, respectively), with variable alterations in facial angle (0.55°, 1.85°, and 1.00°, respectively) depending on the specific expression. CONCLUSION: This MRI-based study indicates that the zygomaticus major muscle experiences isotonic contraction, characterized by decreased length and increased width and thickness. The findings underline the importance of muscle thickness as a reliable parameter in assessing facial muscle function and offer valuable guidance for practitioners in accurately evaluating muscle performance during different facial expressions. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. 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 Gaze into the Eyebrow Standards of Asian Versus Caucasian Women.

BACKGROUND: Eyebrow position affects perceived facial expression and youthfulness, and its modification is a key component of facial rejuvenation. OBJECTIVE: This investigation aimed to assess the preferred vertical eyebrow position, apex location, and eyebrow shape in Caucasian and Asian individuals and to analyze gaze patterns during aesthetic judgment using eye-tracking technology. MATERIALS AND METHODS: The study included 76 Asian and Caucasian volunteers with no medical background. Eye movements were captured with a Tobii Pro Nano eye-tracker. Participants viewed AI-generated images of Caucasian and Asian females with varied eyebrow positions (ratios 1:1.3 to 1:2.5), shapes (angles 8° to 20°), and apex positions. Aesthetic preferences were rated on a 5-point Likert scale. Eye-tracking metrics and aesthetic ratings were statistically analyzed using ANOVA and bivariate correlations. RESULTS: Both genders across ethnicities preferred a moderate eyebrow position ratio of 1:1.6. For eyebrow shapes, a 12° angle received the highest ratings, while extremes were less favored, indicating a preference for moderately curved eyebrows. The most appealing apex position was above the lateral canthus for Asians, and halfway between the lateral limbus and lateral canthus for Caucasians. Eye-tracking revealed longer fixations on unattractive features, suggesting more complex cognitive processing, while attractive features were processed more efficiently. CONCLUSION: The study revealed that aesthetic preferences for eyebrow features are influenced by both ethnic background and gender, with a general preference toward moderately curved eyebrows and subtle variations in preferred positions. These findings suggest a need for culturally sensitive approaches in facial aesthetic procedures and highlight the potential of eye-tracking technology to enhance surgical planning. Surgeons are advised to adopt a conservative, patient-centered approach when modifying eyebrow features, considering individual and cultural aesthetics to maximize patient satisfaction. 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 .

Eye-Tracking Insights into the Perception of Buttocks.

BACKGROUND: Aesthetic enhancements to the buttock region have grown in demand due to media influence and evolving beauty standards. Using eye-tracking technology, we sought to uncover subconscious visual preferences regarding the buttock aesthetic. The objective of this investigation was to assess visual gaze patterns in assessing female buttocks among Caucasian and Asians through eye-tracking technology. MATERIALS AND METHODS: 67 participants viewed photographs of buttocks from various angles, and eye movements were analyzed using the Tobii Pro Nano eye-tracker. RESULTS: Males fixated on the intergluteal cleft for 0.96 ± 1.1 s and the thigh gap for 0.07 ± 0.2 s; while, females fixated for 0.81 ± 0.9 s and 0.06 ± 0.2 s on the same regions, respectively. Significant gender differences were observed in the intergluteal cleft (p = 0.002) and upper lateral buttock (p < 0.001). CONCLUSION: This study offers new insights into the observation of buttocks. The consistent attention toward the intergluteal cleft across demographics could be of potential significance in the aesthetic perception of buttocks. However, diverse gaze patterns also underscore the multifaceted nature of human attraction. These findings hold implications for plastic surgery, aesthetic medicine, and the sociocultural understanding of beauty. A deeper dive into aesthetic preferences is pivotal for a holistic understanding of human perceptions of attractive buttocks. LEVEL OF EVIDENCE III: 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 Table of Contents or the online instructions to Authors www.springer.com/00266 .

Understanding Platysma Muscle Contraction Pattern and Its Relationship to Platysmal Banding: A Real-Time Ultrasound Study.

BACKGROUND: Addressing neck contouring with surgical and nonsurgical aesthetic procedures includes understanding the origin of platysmal banding. A theory was postulated to explain this phenomenon by isometric vs isotonic muscular contraction patterns. However, no scientific proof had been provided to date for its correctness. OBJECTIVES: The aim of this study was to confirm the correctness of the platysmal banding theory based on isometric vs isotonic muscular contractions. METHODS: Eighty platysma muscles from 40 volunteers (15 males and 25 females) were investigated (mean age 41.8; SD 15.2 years; mean BMI of 22.2; SD 2.3 kg/m2). Real-time ultrasound imaging was utilized to measure the increase in local muscle thickness inside and outside of a platysmal band as well as platysma mobility. RESULTS: Within a platysmal band, the local thickness of the muscle increases during muscular contractions by 0.33 mm (37.9%; P < .001). Outside of a platysmal band the thickness of the platysma muscle decreased by 0.13 mm (20.3%; P < .001). It was identified that within a platysmal band no gliding was detectable, whereas outside of a band an average muscle gliding of 2.76 mm was observed. CONCLUSIONS: The results confirm the correctness of the isometric vs isotonic platysma muscle contraction pattern theory: isotonic muscle contraction (gliding without increase in tension and therefore in muscle thickness) vs isometric muscle contraction (no gliding but increase in tension and therefore in muscle thickness). These 2 types of contraction patterns occur within the platysma simultaneously and are an indicator for zones of adhesion in the neck to guide surgical and nonsurgical aesthetic procedures.

Increasing Precision When Targeting the Depressor Anguli Oris Muscle With Neuromodulators: An Ultrasound-Based Investigation.

BACKGROUND: Neuromodulator treatments of the perioral region are increasingly popular and aim to modulate the position of the modiolus. The predominantly targeted muscle is the depressor anguli oris (DAO) which allows for the modiolus to reposition cranially once temporarily relaxed. OBJECTIVES: The aim of this study was to identify the precise anatomic position of the DAO in relation to the marionette line, thereby increasing precision and reducing adverse events during neuromodulator treatments. METHODS: A total of n = 80 DAO muscles were investigated in n = 40 healthy, toxin-naïve volunteers (11 males, 29 females) with a mean [standard deviation] age of 48.15 [15] years and a mean BMI of 24.07 [3.7] kg/m2. The location of the DAO in relation to the labiomandibular sulcus, and its depth, extent, and thickness were investigated with high-frequency ultrasound imaging. RESULTS: The skin surface projection of the labiomandibular sulcus separates the DAO into medial and lateral portions. The distance between skin surface and muscle surface was on average 4.4 mm, with males having a greater distance (P < .001) and higher BMI being an important influencing factor for a greater distance (P < .001). The thickness of the DAO was on average 3.5 mm, with a range of 2.8 to 4.8 mm and with females having thinner muscles compared with males (P < .001). The most favorable injection depth was calculated to be 6.1 mm for intramuscular product placement. CONCLUSIONS: Understanding the perioral anatomy and the influence of age, sex, and BMI will potentially allow injectors to increase the efficacy and duration of neuromodulator treatments while expertly managing adverse events.

Identifying Levels of Competency in Aesthetic Medicine: A Questionnaire-based Study.

BACKGROUND: In 2022, the US experienced a significant increase in demand for minimally invasive aesthetic procedures, underscoring its rising acceptance amid an unregulated educational environment for practitioners. The absence of standardized educational pathways and quality control in aesthetic medicine, primarily provided by nonacademic institutions, highlights a critical need for establishing educational standards to ensure practitioner competence and patient safety. OBJECTIVES: The aim of this study was to identify levels of competency for the aesthetic practitioner and necessary achievement milestones during the educational path from novice to expert injector. METHODS: A total of n = 386 international study participants responded to an online questionnaire regarding their experience in aesthetic medicine practice. The questionnaire comprised 58 questions focusing on professional data, the perceived difficulty of injection, and risk for the occurrence of adverse events for specific facial regions in soft tissue filler and toxin injections. RESULTS: Regardless of medical specialty and experience level, averages of 3.85 (1.8) years, 786.4 (2628) filler injections and 549.9 (1543) toxin injections were estimated to progress from novice to advanced injector, while averages of 6.10 (3.7) years, 1842.2 (4793) filler injections, and 1308.5 (3363) toxin injections were estimated to advance from advanced to expert injector. The nose and the perioral region have been ranked as the facial regions where it is most difficult to achieve a perfect aesthetic outcome and with the greatest risk for the occurrence of adverse events for filler and toxin injections, respectively. CONCLUSIONS: In this study we establish an educational framework in aesthetic medicine by defining the progression from novice to competent and expert injector levels, suggesting 4 years of practice and over 790 filler and 550 neuromodulator injections for competence, and at least 6 years with 1840 filler and 1310 neuromodulator injections for expertise. We also identify critical facial regions for targeted treatments by different expertise levels.

The Relationship Between Glabellar Contraction Patterns and Glabellar Muscle Anatomy: A Magnetic Resonance Imaging-based Study.

BACKGROUND: Glabellar contraction patterns were introduced to the scientific literature to help guide glabellar neuromodulator injection algorithms. However, the relationship between the underlying musculature and its influence on these glabellar contraction patterns is unclear. OBJECTIVES: The aim of this study was to identify via Magnetic Resonance Imaging (MRI) glabellar muscle parameters that display an influence on the distribution of individual glabellar contraction patterns. METHODS: Thirty-four healthy young individuals of Caucasian Polish descent were investigated (17 women, 17 men) with a mean age of 23.6 years and a mean BMI of 22.8 kg/m2. MRI-based measurements of length, thickness, width and surface area of procerus, corrugator supercilii, orbicularis oculi and frontalis muscles were conducted. RESULTS: Unadjusted models revealed that there was no statistically significant difference between the five glabellar contraction types and the investigated muscle parameters indicating that independent of the skin rhytid pattern, the underlying musculature was not different between the investigated groups in this sample with all p ≥ 0.102. Adjusted models revealed that sex was the most influential factor due to males displayed in general higher values for the investigated parameters when compared to females. CONCLUSIONS: The results of this study reveal that based on the MRI parameters investigated and based on the investigated cohort, there does not appear to be a strong relationship between glabellar contraction patterns and underlying glabella muscle anatomy. Utilizing glabellar contraction patterns to design neuromodulator treatment algorithms may be of variable clinical merit.

One-Year Data on the Longevity and Safety of Hyaluronic Acid Filler for Static Horizontal Neck Rhytids.

BACKGROUND: The long-term efficacy and safety of hyaluronic acid fillers injected into the neck have yet to be analyzed in a prospective trial in the United States. OBJECTIVE: Analyze the long-term efficacy and safety of a hyaluronic acid filler for static horizontal neck rhytids. MATERIALS AND METHODS: Twenty-six subjects were enrolled in the study. Six subjects were randomized to receive saline and 20 subjects were randomized to receive HA RR. All subjects were randomized to use a cannula on 1 side and needle on the other with optional retreatment on day 30 and optional crossover treatment with different assignment on day 60. The subjects were graded using the Transverse Neck Line Scale, Canfield photography, and the Global Aesthetic Improvement Scale on day 360. RESULTS: A significant improvement from baseline on day 360 was achieved on the Transverse Neck Line Scale according to the blind evaluator, subjects, and investigator without any delayed-onset or prolonged side effects. There was no significant difference in the average improvement from the short-term analysis on day 60 to the long-term analysis on day 360. CONCLUSION: HA RR achieved significant long-term improvement in static horizontal neck rhytids without any long-term side effects.

The Suitability of a Large Particle Hyaluronic Acid Filler for the Treatment of Temporal Hollowing.

BACKGROUND: Hyaluronic acid (HA) fillers may be manufactured to have distinctive physical properties that optimize their use for specific indications. Fillers manufactured with large gel calibration (particle size; HA-V) may be particularly suitable for volumizing large surface areas such as the temporal hollows. OBJECTIVE: To investigate the safety and effectiveness of HA-V for the treatment of temporal hollows. MATERIALS AND METHODS: A prospective, open-label, single-cohort, clinical trial was conducted. Twenty-six women who presented with bilateral temporal hollows at baseline were recruited. All subjects received treatment with HA-V and were observed at 4 to 5 in-person visits over 16 weeks. Subjective and objective measures of safety and efficacy parameters were collected through 2- and 3-dimensional imagery, questionnaires/scales (i.e., subject satisfaction, global aesthetic improvement, temporal hollowing severity), and adverse event diaries. RESULTS: To achieve optimal correction, the investigator used an average of 1.70 syringes per subject, per side. All treatments were performed using a bolus injection technique to place the product on the periosteum (bone) of the temporal region. Following optimal correction, all subjects (100%) displayed improvement in their global aesthetic appearance, and 25 of 26 subjects (96.15%) displayed ≥1 grade improvement on the temporal volume scale. Subject satisfaction was high, with 91.3% of subjects being satisfied with the appearance of their temporal regions following optimal correction. CONCLUSION: In this pivotal trial, HA-V was evidenced to have an excellent safety profile and proven efficacy up to 16 weeks, making it a suitable HA filler for volumization of the temporal region.

Investigating the Anatomic Location of Soft Tissue Fillers in Noninflammatory Nodule Formation: An Ultrasound-Imaging-Based Analysis.

INTRODUCTION: Noninflammatory nodules may be persistent to dissolve. To evaluate the possible reasons, a case series of ultrasound images and medical data of patients who were prospectively referred with noninflammatory nodules were evaluated. MATERIALS AND METHODS: A total of 27 patients with nodules but without signs of inflammation were included. All cases were assessed with an 18-MHz linear ultrasound device. Exact location of the filler material was noted. Relations with clinical data were analyzed using chi-square tests. RESULTS: Early onset of complaints (<2 weeks) was found in 16 patients and late onset (>2 weeks) in 11. All patients had multiple nodules. In all cases, the filler nodule was found to be located inside the fascia. Extension to the subcutaneous tissue was seen in 8 cases and to the deeper planes in 5. In 14 cases, the filler material was completely located inside layers of the fascia, and migration was observed in 5 cases. DISCUSSION: Accumulation of filler material in the superficial musculoaponeurotic system or fascia may be an important cause for the occurrence of persistent noninflammatory nodules, either by initial faulty injection technique or by later accumulation through the pathway generated with a needle or cannula. Ultrasound-guided injections are helpful to dissolve the nodule.

The perception of lip aesthetics in the context of facial proportions-An eye-tracking-based analysis.

BACKGROUND: Minimally invasive lip volumizing and contouring soft tissue filler procedures are frequently requested by both female and male aesthetic patients. Guidance on how to achieve the most beautiful outcome is inconsistent. OBJECTIVE: To investigate what the most beautiful proportions are in relation to vermillion thickness, the distance of the upper and lower lip in relation to nose and chin, and relation to the bigonial distance. METHODS: This study included a total of n = 101 volunteers (52 females, 49 males, 100% Caucasian) who inspected frontal images of modified facial proportions and answered a related questionnaire showcasing the same images. Image presentation followed a randomized sequence both for the eye tracking and for the survey component of this study but was equal for all observers. RESULTS: The most attractive vertical position of lips was the 1:2 ratio in which the distance between lips and chin is double the length as the distance between lips and nose. For the ratio between the width of the lips and the bigonial distance, it was the 1:2.5 ratio, whereas for the thickness of the upper lip vermilion in relation to the upper lip ergotrid it was the 1:3/1:2 (male/female) ratio and for the lower lip vermilion and lower lip ergotrid it was the 1:4 ratio for both genders. CONCLUSION: The results of this eye tracking and survey-based investigation revealed that instead of one single universal ratio, multiple facial proportions exist that are perceived as most attractive/masculine/feminine. Regarding the perception of facial aesthetics, it appears there is a distinction between attractiveness and masculinity/femininity: the most attractive male/female face is not necessarily the most masculine or feminine.

ChatGPT's quiz skills in different otolaryngology subspecialties: an analysis of 2576 single-choice and multiple-choice board certification preparation questions.

PURPOSE: With the increasing adoption of artificial intelligence (AI) in various domains, including healthcare, there is growing acceptance and interest in consulting AI models to provide medical information and advice. This study aimed to evaluate the accuracy of ChatGPT's responses to practice quiz questions designed for otolaryngology board certification and decipher potential performance disparities across different otolaryngology subspecialties. METHODS: A dataset covering 15 otolaryngology subspecialties was collected from an online learning platform funded by the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery, designed for board certification examination preparation. These questions were entered into ChatGPT, with its responses being analyzed for accuracy and variance in performance. RESULTS: The dataset included 2576 questions (479 multiple-choice and 2097 single-choice), of which 57% (n = 1475) were answered correctly by ChatGPT. An in-depth analysis of question style revealed that single-choice questions were associated with a significantly higher rate (p < 0.001) of correct responses (n = 1313; 63%) compared to multiple-choice questions (n = 162; 34%). Stratified by question categories, ChatGPT yielded the highest rate of correct responses (n = 151; 72%) in the field of allergology, whereas 7 out of 10 questions (n = 65; 71%) on legal otolaryngology aspects were answered incorrectly. CONCLUSION: The study reveals ChatGPT's potential as a supplementary tool for otolaryngology board certification preparation. However, its propensity for errors in certain otolaryngology areas calls for further refinement. Future research should address these limitations to improve ChatGPT's educational use. An approach, with expert collaboration, is recommended for the reliable and accurate integration of such AI models.