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.

Simulating Upper Eyelid Ptosis During Neuromodulator Injections-An Exploratory Injection and Dissection Study.

BACKGROUND: Aesthetic neuromodulator injections of the upper face are frequently performed to temporarily block muscular actions of the periorbital muscles to ultimately reduce skin rhytids. However, the adverse event rate in the literature for toxin-induced blepharoptosis ranges from 0.51% to 5.4%. OBJECTIVE: To identify access pathways by which injected neuromodulator product can travel from extra- to intra-orbital and therefore affect the levator palpebrae superioris muscle. METHODS: Nine non-embalmed human body donors were investigated in this study with a mean age at death of 72.8 (16.1) years. The 18 supraorbital regions were injected in 28 times (14 for supratrochlear and 14 for supraorbital) with 0.5 cc, whereas eight cases (four for supratrochlear and four supraorbital) were injected with 0.1 cc of colored product. Anatomic dissections were conducted to identify structures stained by the injected color. RESULTS: The results of this injection- and dissection-based study revealed that both the supratrochlear and the supraorbital neurovascular bundles are access pathways for injected neuromodulator products to reach the intra-orbital space and affect the levator palpebrea superioris muscle. Out of 36 conducted injection passes, seven (19.44%) resulted in affection of the sole elevator of the eyelid of which 100% occurred only at an injection volume of 0.5 cc and not at 0.1 cc. CONCLUSION: Clinically, the results indicate that a low injection volume, a superficial injection for the supraorbital location, and angling the needle tip away from the supratrochlear foramen (toward the contralateral temple) when targeting the corrugator supercilii muscles, can increase the safety profile of an aesthetic toxin glabellar treatment.

Bridging the Gap Rather Than Filling the Entire Valley-Anatomic Insights When Treating the Medial Infraorbital Region.

BACKGROUND: The treatment of the medial infraorbital region also termed the tear trough has become increasingly popular by the use of soft tissue fillers in a minimally invasive approach using a cannula. METHODS: A total of 246 tear troughs were injected and investigated originating from 123 study participants. The clinical outcome was evaluated 6 months after the treatment by independent observers based on standardized frontal images and the procedure was documented by ultrasound imaging. RESULTS: On average, 0.26 (0.1) cc [range: 0.08-0.32] of soft tissue filler material was injected per tear trough. Tear trough depth was before the treatment rated as 2.12 (0.4), whereas after the treatment it was 1.15 (0.4) (p < 0.001). Hyperpigmentation score was 2.19 (0.4) before the treatment, whereas after the treatment it was 1.31 (0.5) (p < 0.001). Intraorbital fat pseudo-prolapse severity was rated before the treatment 1.88 (0.7), whereas it was rated after the treatment 1.14 (0.3) (p < 0.001). Wrinkle severity of the lower eyelid was rated before the treatment 1.51 (0.6), whereas it was rated after the treatment 1.12 (0.3) (p < 0.001). CONCLUSION: The results of this retrospectively investigated case series revealed that the conducted injection technique for treating the tear trough for medial infraorbital hollowing with a cannula provided statistically significant clinical improvement with a limited adverse events profile. The technique utilized an injection approach which was perpendicularly oriented to the longitudinal axis of the tear trough thereby "bridging the gap instead of filling the entire valley."

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.

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 .

Pharmacologic and Other Noninvasive Treatments of the Aging Face: A Review of the Current Evidence.

SUMMARY: Aging of the face is the result of the interrelation of three-dimensional changes occurring over time among the 5 different layers of the face and its associated structures. Knowledge regarding the causes of these changes and identification of new key anatomic structures have helped elucidate one of the most complex areas of the human body. This has resulted in the introduction of pharmacologic agents to help stop, mitigate, or counteract signs of aging and restore the youthful appearance of the face. The authors performed a systematic search of the literature to review the current highest-level evidence of facial antiaging pharmacologic agents. Pharmacologic and minimally invasive antiaging treatments can target different components of facial aging and continue to evolve. With continuous research efforts, traditional treatments, such as botulinum toxin type A, injectable fillers, and chemical peels, are emerging in newer, more effective formulations, with longer lasting clinical results. However, for soft-tissue descent and facial volume loss, surgery remains the standard treatment. An adequate understanding of the three-dimensional process of facial aging over time (the fourth dimension), facial anatomy, and the pharmacologic properties of antiaging/rejuvenation agents are the sine qua non of facial antiaging treatment. The specific modality should be tailored to patient characteristics, preferences, and goals.

AI assistance in aesthetic medicine-A consensus on objective medical standards.

BACKGROUND: Aesthetic medicine has traditionally relied on clinical scales for the objective assessment of baseline appearance and treatment outcomes. However, the scales focus on limited aesthetic areas mostly and subjective interpretation inherent in these scales can lead to variability, which undermines standardization efforts. OBJECTIVE: The consensus meeting aimed to establish guidelines for AI application in aesthetic medicine. MATERIALS AND METHODS: In February 2024, the AI Consensus Group, comprising international experts in various specialties, convened to deliberate on AI in aesthetic medicine. The methodology included a pre-consensus survey and an iterative consensus process during the meeting. RESULTS: AI's implementation in Aesthetic Medicine has achieved full consensus for enhancing patient assessment and consultation, ensuring standardized care. AI's role in preventing overcorrection is recognized, alongside the need for validated objective facial assessments. Emphasis is placed on comprehensive facial aesthetic evaluations using indices such as the Facial Aesthetic Index (FAI), Facial Youth Index (FYI), and Skin Quality Index (SQI). These evaluations are to be gender-specific and exclude makeup-covered skin at baseline. Age and gender, as well as patients' ancestral roots, are to be considered integral to the AI assessment process, underlining the move towards personalized, precise treatments. CONCLUSION: The consensus meeting established that AI will significantly improve aesthetic medicine by standardizing patient assessments and consultations, with a strong endorsement for preventing overcorrection and advocating for validated, objective facial assessments. Utilizing indices such as the FAI, FYI, and SQI allows for gender-specific, age adjusted evaluations and insists on a makeup-free baseline for accuracy.

Deliberations of the Safety Task Force: Risk factors and treatment of adverse events associated with aesthetic injectables.

BACKGROUND: The growing popularity of aesthetic procedures involving fillers, biostimulators, and neurotoxins has prompted concerns about patient safety. To address these concerns, a global Safety Task Force (STF) was formed. AIMS: The inaugural STF meeting prioritized vascular compromise prevention and management, guiding clinical trial design and materials for future meetings, and collecting data from experts on current safety methods. METHODS: The STF was formed and consisted of 16 experts from nine different countries, with each possessing distinct expertise in various fields related to aesthetic injectables. Current safety data, protocols, knowledge gaps and future research priorities were discussed and voted upon. RESULTS: The establishment of a global database for tracking filler-related AEs was favored by 93% of participants. Discussions revolved around the database's scope, data standardization, and whether non-medical contributors should be included. Aspiration as a safety technique garnered support from 73% of participants. Approximately 43% of participants incorporate ultrasound in their injections, with divergent opinions on its impact and potential when used as a standard of practice versus in AE management. Most physicians on the task force incorporated cannula use for some of their injections (93%). There were varying perspectives on treatments for vascular adverse events (VAE), the primary causes, and the adoption of new protocols in the field. CONCLUSIONS: The STF meeting underscored the need for a coordinated effort to address complications related to HA fillers, including VAE management and hyaluronidase protocols. Reliable treatment endpoints were evaluated, but improved measurement methods are needed. Future meetings will focus on addressing delayed complications, furthering safety in this field.

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.

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 .

Pitanguy Ligament Preservation in Structural Precision Rhinoplasty.

The Pitanguy ligament is a crucial structure in nasal tip support and in maintaining the integrity of the soft tissue envelope of the nose. In this cadaveric study, we dissected out the Pitanguy ligament on a series of fresh human cadaver specimens to better elucidate the structure of the ligament and its fate in open rhinoplasty. The Pitanguy ligament can act as a tethering force to the nasal tip when reshaping the nasal tip. Release of the Pitanguy ligament alleviated downward tension on the nasal tip, and tip shaping to a more appropriate position demonstrated that this ligament was displaced from its ideal position. In patients seeking rhinoplasty, this structure may require release and reconstruction to successfully alter tip position and avoid supratip deformity.

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 .

Influence of ethnicity on aesthetic preferences for lip characteristics in Caucasian male and female faces.

BACKGROUND: In an era where globalization and social media significantly reshape beauty standards, it is imperative to delve into the subjectivity of beauty and attractiveness. The lips, a key element in facial aesthetics, contribute significantly to the perception of attractiveness, and also have a profound impact on an individual's self-esteem. OBJECTIVE: To analyze the influence of ethnicity on the aesthetic preferences for lip characteristics, among male and female faces. MATERIALS AND METHODS: This study encompassed a sample of 231 study participants (153 women and 78 men) with an average age of 23.2 ±â€¯2.8 years, representing ethnicities such as African, Caucasian, Middle Eastern, and South Asian. Participants were asked to rate a series of images showcasing various lip variants, providing insights into their aesthetic preferences. RESULTS: Demographic analysis revealed gender and ethnic variations in aesthetic preferences for all the investigated lip parameters. Women were 2.42 times more likely than men to prefer no Cupid's indentation on a female model (p = 0.0019). CONCLUSIONS: The study underscores the importance of understanding cultural influences on beauty standards and challenges the notion of a universal beauty ideal. The evolving role of social media trends, such as Cupid's bow indentation elimination, raises questions about the dynamic nature of aesthetic preferences among different ethnicities.

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.

In-depth analysis of ChatGPT's performance based on specific signaling words and phrases in the question stem of 2377 USMLE step 1 style questions.

ChatGPT has garnered attention as a multifaceted AI chatbot with potential applications in medicine. Despite intriguing preliminary findings in areas such as clinical management and patient education, there remains a substantial knowledge gap in comprehensively understanding the chances and limitations of ChatGPT's capabilities, especially in medical test-taking and education. A total of n = 2,729 USMLE Step 1 practice questions were extracted from the Amboss question bank. After excluding 352 image-based questions, a total of 2,377 text-based questions were further categorized and entered manually into ChatGPT, and its responses were recorded. ChatGPT's overall performance was analyzed based on question difficulty, category, and content with regards to specific signal words and phrases. ChatGPT achieved an overall accuracy rate of 55.8% in a total number of n = 2,377 USMLE Step 1 preparation questions obtained from the Amboss online question bank. It demonstrated a significant inverse correlation between question difficulty and performance with rs = -0.306; p < 0.001, maintaining comparable accuracy to the human user peer group across different levels of question difficulty. Notably, ChatGPT outperformed in serology-related questions (61.1% vs. 53.8%; p = 0.005) but struggled with ECG-related content (42.9% vs. 55.6%; p = 0.021). ChatGPT achieved statistically significant worse performances in pathophysiology-related question stems. (Signal phrase = "what is the most likely/probable cause"). ChatGPT performed consistent across various question categories and difficulty levels. These findings emphasize the need for further investigations to explore the potential and limitations of ChatGPT in medical examination and education.

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 .

Increasing precision during neuromodulator injections for frontal rhytids-Using ultrasound imaging to identify the line of convergence.

BACKGROUND: Recent research introduced the concept of the "line of convergence" as a guide for injectors to enhance precision and avoid complications when treating the frontalis muscle with toxins. However, currently, no pre-injection ultrasound scanning is employed to increase precision and reduce adverse events when searching for the line of convergence. OBJECTIVE: To explore the feasibility and practicality of implementing pre-injection ultrasound scanning into aesthetic neuromodulator treatments of the forehead. METHODS: The sample of this study consisted of n = 55 volunteers (42 females and 13 males), with a mean age of 42.24 (10.3) years and a mean BMI of 25.07 (4.0) kg/m2. High-frequency ultrasound imaging was utilized to measure the thickness, length, and contractility of the frontal soft tissue and to determine the precise location of the line of convergence during maximal frontalis muscle contraction. RESULTS: The results revealed that the line of convergence was located at 58.43% (8.7) of the total forehead height above the superior border of the eyebrow cilia without a statistically significant difference between sex, age, or BMI. With frontalis muscle contraction, the forehead shortens in males by 25.90% (6.5), whereas in females it shortens only by 21.74% (5.1), with p < 0.001 for sex differences. CONCLUSION: This study demonstrated the feasibility and practicality of pre-injection ultrasound scanning for facial aesthetic neuromodulator treatments. Knowing the location of the line of convergence, injectors can determine precisely and on an individual basis where to administer the neuromodulator deep or superficial or when the injection location is at risk to cause eyebrow ptosis.

Preventing Hump Recurrence in Dorsal Preservation Rhinoplasty: The Five Key Tenets.

SUMMARY: Preservation rhinoplasty has re-emerged over the past decade and continues to gain traction in the rhinoplasty community. Dorsal preservation rhinoplasty (DPR), one of the tenets of preservation rhinoplasty, centers on preservation of the native osseocartilaginous joint of the dorsum, with changes instead achieved through modification of the underlying septal cartilage and surrounding bony nasal pyramid. However, one complication unique to DPR is the phenomenon of hump recurrence, where tensile forces or memory lead to a recurrent convexity of the dorsal hump. Hump recurrence is the most common complication after DPR and often requires revisionary surgery. Accordingly, strategies to reduce the incidence of hump recurrence are highly sought after. In this article, we describe the senior author's main tenets of preventing hump recurrence in DPR, focusing on 1. Appropriate patient selection; 2. Addressing anatomic blocking points; 3. Adding mechanical fixation of the cartilaginous vault with suture techniques depending on the level of septal manipulation; 4. Applying a graduated approach to DPR procedural selection; and 5. Ancillary measures to control the shape of the nasal dorsum. Implementation of each of these five tenets is critical for modern rhinoplasty surgeons to reduce the incidence of hump recurrence in their preservation rhinoplasty practices.