Frontalis Muscle Research Articles

Effect of Synchronized Radiofrequency and High-Intensity Facial Electrical Stimulation (HIFES) of the Upper Face.

Effects of upper facial aging can present as static forehead and periorbital rhytids as well as soft tissue volume loss. The latter can prompt in conjunct with bony changes of the calvaria eyebrow and eyelid ptosis. Injection-based treatments can yield positive outcomes but are not free of procedural risks. To assess the clinical outcome of synchronized radiofrequency (RF) and high intensity facial electric stimulation (HIFES) when targeting the upper face with special focus on the effects of musculature, subcutaneous fatty layer, and eyebrow position. This non-randomized, prospective study included 37 subjects with a mean age of 45.46 years and a mean BMI of 21.84 kg/m2. Subjects received four synchronized RF and HIFES treatments spaced seven days apart. Efficacy measurements were taken at 4-, 16-, and 24-weeks post-treatment using three-dimensional surface imaging, surface electromyography (EMG), and high-resolution facial ultrasound. Forehead and lateral canthal line severity improved statistically significantly at each follow-up visit when compared to baseline with all p<0.001. At week 24, the position of medial/central/lateral eyebrows increased by 3.18/3.02/2.27 mm when compared to baseline with p < 0.001, respectively. At week 24, no statistically significant changes were observed in the thickness of frontalis muscle or of the overlying fatty layer. The application of synchronized RF and HIFES to the frontal region reduced frontal and lateral canthal rhytids and elevated the position of the eyebrow until week 24 after the initial treatment. Based on the results obtained, this non-invasive energy-based treatment option could be a viable alternative to injectable treatments of the upper face when trying to ameliorate the signs of upper facial aging.

Functional reconstruction of lower eyelid using paramedian forehead flap combined with frontalis muscle and periosteum

Both cosmetic and functional aspects are important in the reconstruction of lower eyelid tissue defects. In this case report, we describe a two-stage reconstruction of a skin defect, including the orbicularis oculi muscle, after resection of a basal cell carcinoma using a paramedian forehead flap combined with the frontalis muscle and periosteum. In the first stage, the paramedian forehead flap, including the frontalis muscle and periosteum, was elevated, the periosteal flap was fixed to the outer orbital periosteum to lift the lower eyelid, and the skin flap, including the frontalis muscle, was sutured to the defect. In the second stage, the flap was divided and the frontalis muscle flap was sutured to the medial palpebral ligament. Electromyography at 1 year postoperatively confirmed neurotization of the transferred muscle, and at 6 months, voluntary contraction of the transferred muscle was observed during eyelid closure. These results suggest that a paramedian flap combined with the frontalis muscle and periosteum is a useful option for reconstructing horizontal skin defects involving the orbicularis oculi muscle.

Bifurcating Method for Subcutaneous Indwelling of Nonabsorbable Threads.

Subcutaneous indwelling of nonabsorbable threads for tissue fixation and tension reduction is often used in plastic surgery and is applied in breast reduction surgery, umbilicoplasty, and in frontalis muscle lifting for congenital ptosis. However, in a few cases, exposure of the indwelling thread necessitates its removal. Exposure of the indwelling threads mostly occurs due to exposure of the knots. Therefore, we require a novel method to ensure that the knot of the indwelling thread remains unexposed. Hence, we created a stab incision to place the indwelling nonabsorbable threads ligated with moderate tensile force. Furthermore, we attached needles to each end of the ligated thread. The needles penetrated from the stab incision through the depths to separate sites farther away from each other. Finally, we towed and cut the exposed thread from the skin. Thus, the knots on the indwelling thread may be positioned deeper, reducing the risk of exposure to the indwelling thread. Furthermore, the risk of overcorrection is reduced as each end of the indwelling threads penetrates a different site. In addition, this method leaves certain length of the end of the knot under the skin, which improves the visibility of the indwelling thread during revision surgery, facilitates access, and reduces the operative time. Application of this method in subcutaneous indwelling of nonabsorbable threads may reduce complications and time required for revision surgery.

Background factors for postoperative eyebrow descent in blepharoptosis: A retrospective case-control study of 93 patients.

Upper blepharoplasty for ptosis aims to achieve functional and aesthetic outcomes. However, postoperative eyebrow descent is a potential complication that can affect surgical outcomes. This descent reflects the return of the brow to its normal position due to the release of compensatory frontalis muscle activity for ptosis. Identifying patients with this outcome may improve aesthetic results. This retrospective case-control study analyzed 93 patients who underwent upper blepharoplasty to identify factors associated with postoperative eyebrow descent and measure eyebrow positions before and 1.5 months after surgery. Data included patient age, sex, pre- and postoperative margin reflex distance-1, skin excision height, and levator aponeurosis advancement distance. The results showed that postoperative eyebrow descent (≥5%) occurred in 61% of the patients. Significant associations were found between postoperative eyebrow descent and sex (p = 0.028), preoperative eyebrow descent at eyelid closure (p < 0.001), and skin excision height (p = 0.012). Male patients had a significantly higher incidence of postoperative eyebrow descent, most likely due to larger skin excisions. For patients with preoperative eyebrow descent at eyelid closure and those requiring larger skin excisions, considering the possibility of postoperative eyebrow descent may improve aesthetic outcomes.

Exploratory Analysis of Upper Facial Muscle Interplay During Emotional Expressions: Magnetic Resonance Imaging (MRI) Insights from Young, Caucasian, Toxin-naïve Individuals.

Understanding the interplay of muscle activity in the upper face is crucial as it can significantly impact the effectiveness and safety of aesthetic treatments. Traditional injection algorithms typically focus on the general 2D and 3D anatomy of muscles, often neglecting the areas where muscles exert the greatest force during facial expressions. To analyze the location of greatest morphological change in upper facial muscles procerus muscle (PM), corrugator supercilia muscle (CSM), orbicularis oculi muscle (OOM) and frontalis muscle (FM) during various facial expressions. A total of 34 healthy young individuals (17 females, 17 males), with a mean age of 23.6±2.4 years [range 20-30], were examined using MRI to assess the length, thickness and width of upper facial muscles (PM, CSM, OOM, FM) for five different facial expressions: repose, anger, joy, surprise, and sadness. Facial muscle thickness is a key indicator of activity during expressions like anger, joy, surprise, and sadness. During anger, the PM and CSM decreased in length and width but increased in thickness, while FM passively contracted to stabilize the expression. The OOM showed increased thickness in its medial, inferior, lateral, and superior portions during various expressions, with specific regions activating differently depending on the expression, such as the medial and lateral parts during surprise and the inferior and lateral parts during joy. The medial third of the CSM was the most active region during contraction. Upper facial muscles - regardless of them agonists or antagonists - act together during facial expressions to stabilize facial expressions, emphasizing the need to assess both groups in neuromodulator treatments. The medial third of the corrugator supercillii shows the most significant MRI changes, making it the primary target for injections.

Frontal Suspension Procedure using Frontalis Muscle for Management of Ptosis

Background : Ptosis has a reputation as a cosmetic problem, but it is more often as a functional deficit that can have real impact on patients’ lives. Ptosis results from the dysfunction of one or both of the upper eyelid retractors and often blocks peripheral vision. Ptosis can be congenital or caused by aging. Frontal suspension is one of few techniques for correction of ptosis especially for severe ptosis. Patient and Method : We reported one case of severe ptosis. The patient had bilateral congenital ptosis at both of upper eyelids. The upperlid excursion was 4 mm and marginal reflex distance (MRD) was 2 mm. A frontal suspension procedure using frontalis muscle was done for correction. Result : After frontal suspension procedure, MRDare 5 mm for both eyes. There wee no difficulty for closing the eyes. The cosmetic appearance was good. Patient was satisfied with the result. Conclusion : Frontal suspension procedure using frontalis muscle gives a good function and cosmetic result for severe ptosis.

Botulinum Toxin: A Non-surgical Approach for Non-myasthenic Mild-to-Moderate Blepharoptosis Treatment.

Mild-to-moderate blepharoptosis can be aesthetically displeasing for patients, particularly in cases involving a single eyelid. However, certain patients are reluctant to undergo surgical intervention. Botulinum neurotoxin A (BoNT-A) injection offers a potential solution in such cases. Patients meeting the following inclusion criteria were included in the study: mild-to-moderate eyelid ptosis of different etiologies (excluding myasthenic disorders), robust activity of the orbicularis oculi muscle, proficiency in Italian language, standardized pre- and postoperative photo-documentation, and signed consent for study participation. A 32-33 Gauge 4-mm needle was employed to inject the BoNT-A in the pretarsal orbicularis muscle. Standardized videos and photos were obtained before the treatment, 2 weeks, 4 weeks, and 24 weeks post-treatment. Outcomes were evaluated by measuring changes in the margin reflex distance-1 (MRD-1) and assessing patient point of view through two subjective questionnaires. Forty-nine patients were enrolled, 39 females and 10 males, aged between 30 and 88 years old. We observed a significant increase in the MRD-1 after 2 weeks and after 4 weeks compared to the baseline (p < 0.0001), with a mean elevation of the eyelid of 0.71 mm and 0.67 mm respectively. Patients ceased to require furrowing of the frontalis muscle to compensate for the eyelid elevation dysfunction. After 24 weeks, the BoNT-A effect diminished, and the treated eyelid returned to its baseline position. 67.4% of patients reported an improvement with only mild inconvenience in their blepharoptosis, and 16.3% of patients reported a complete improvement. 85.7% of patients expressed the desire to undergo the treatment again. BoNT-A has demonstrated effectiveness in temporarily managing mild-to-moderate blepharoptosis and may represent a viable option for addressing minor eyelids asymmetries. 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 .

Effectiveness of Kabat Technique versus Mirror Book Therapy on clinical and electrophysiological parameters in patients with Bell’s palsy: a comparative interventional study

BackgroundBell’s palsy significantly impacts facial function, aesthetics, and quality of life.ObjectiveTo compare the effects of the Kabat Technique (KT) and Mirror Book Therapy (MBT) on clinical and electrophysiological parameters in patients with Bell’s palsy.MethodsThis randomized controlled trial included 31 patients divided into two groups: KT (n = 16) and MBT (n = 15). Both groups received their respective interventions (6 days/week for 3 weeks) in addition to conventional physiotherapy. Sunnybrook Facial Grading Score and Nerve Conduction Test (amplitude and latency of frontalis, nasalis, and mentalis muscles) were assessed pre- and post-intervention.ResultsStatistical analysis (SPSS v20) revealed significant intragroup improvements in all outcome measures (p < 0.05). Intergroup comparison showed MBT had superior improvements in amplitude of frontalis and reduced latency of nasalis. Both groups demonstrated significant improvement in the Sunnybrook grade shift.ConclusionThis study suggests that KT and MBT, combined with conventional physiotherapy, positively impact clinical and electrophysiological parameters in Bell's Palsy patients. MBT showed superior results in select Nerve Conduction Test parameters.

Deciphering the Refined Musculature of the Brow Area in Asians by Micro-Computed Tomography.

The brow area is an important aesthetic unit. Accurate anatomical understanding of the brow is important for clinical treatments related to this region. Due to the complexity of the brow area and limitations of methods, there are still some controversies regarding its musculature description. This article aims to reveal the detailed musculature using micro-computed tomography (micro-CT) combined with histological staining. Eight fresh cadaver (16 hemifaces) were obtained. Eight hemifaces were processed with phospho-tungstic acid contrast staining for micro-CT scanning and reconstruction. The other corresponding 8 hemifaces were prepared with Masson staining. The orbicularis oculi muscle (OOM), frontalis muscle (FM), depressor supercilii (DS) and procerus muscle (PM) were situated superficially. The FM terminated and connected with its antagonistic muscles at 2-5 mm above the brow but the fusion line descended in lateral third. The corrugator supercilii muscle (CSM) originated from the periosteum, extending laterally and superficially. During its course, it mainly penetrated the FM. CSM had broad subcutaneous insertion, covering about 77.9% ± 7.5% of the hairy brow. CSM fibers connected to the subcutaneous fiber septa to directly transmit contraction force. The soft tissue on the lateral side of the brow was looser than that on the medial side. Our study deepens the understanding of the precise anatomy of the brow area and helps guide clinical practice.

Relationship between fatigue and quantitative electromyography findings in patients with myasthenia gravis

BackgroundFatigue is a common complaint among patients with myasthenia gravis (MG). In this study, we investigated the alterations in muscle morphology in patients with MG experiencing fatigue using quantitative electromyography (QEMG), and explored the relationship between electrophysiological findings and the severity of both fatigue and disease. MethodsWe performed QEMG of the biceps brachii muscle using the peak ratio method and multi-motor unit potential (MUP) analysis across three groups: 18 MG patients with fatigue, 34 MG patients without fatigue, and 33 healthy subjects. Stimulated single-fiber EMG was performed on the frontalis muscle. The severity of perceived fatigue and disease was subsequently assessed using the quantitative myasthenia gravis (QMG) score, the MG-activities of daily living (MG-ADL) profile, self-reported fatigue questionnaires, and handgrip strength measurements. ResultsThe QEMG study revealed a reduced mean MUP duration and size index (SI), in addition to an increased peak ratio in patients with MG (p < 0.05), which tended to be more pronounced in those experiencing fatigue. Compared to healthy subjects, MG patients with fatigue displayed a myopathic pattern characterised by a high peak ratio, short duration, and small-amplitude MUPs, without any increase in the number of phases or small time intervals. The mean peak ratio was positively correlated with the QMG, MG-ADL, and Fatigue Impact Scale total and physical subscores (p < 0.05). Further, MG patients with fatigue exhibited reduced maximum grip strength, which was positively correlated with the mean MUP duration, amplitude, SI, and thickness, and negatively correlated with the mean peak ratio (p < 0.05). No significant differences were observed in the jitter or block measurements (p > 0.05). ConclusionsThe present study investigated electrophysiological findings that were not considered or theorised in prior studies on patients with MG experiencing fatigue. The results of this study suggest that myopathic changes may be a critical pathophysiological component underlying the fatigue associated with MG.

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

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. The aim of this study was to identify by magnetic resonance imaging (MRI) glabellar muscle parameters that display an influence on the distribution of individual glabellar contraction patterns. Thirty-four healthy young individuals of Caucasian Polish descent were investigated (17 females, 17 males) 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. Unadjusted models revealed that there was no statistically significant difference between the 5 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 ≥ .102. Adjusted models revealed that sex was the most influential factor, with males generally displaying higher values for the investigated parameters than females. The results of this study reveal that, based on the MRI parameters investigated and 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.

Compositions of Four Different Arms in the Anatomy of the Frontalis Muscle Revisited.

Compositions of Four Different Arms in the Anatomy of the Frontalis Muscle Revisited.

Comprehensive Mapping and Dynamic Monitoring of the Temporal Branch of the Facial Nerve in Complex Cranial Reconstruction Surgery and Revision Cranioplasty.

Facial nerve (FN) injury is a significant risk during complex cranial reconstruction surgeries, especially in revision cases where normal anatomy is distorted. The authors introduce a technique to mitigate FN injury, including preoperative FN mapping, intraoperative FN mapping, and continuous FN monitoring. Preoperative mapping uses a handheld ball-tip stimulator to elicit compound muscle action potentials (CMAP) in the frontalis muscle. Needle electrodes are placed above the orbital margin to record responses, starting at the stylomastoid foramen and extending until the entire temporal branch is mapped. Intraoperatively, continuous mapping is achieved using an electrified insulated suction device, allowing dynamic mapping during soft tissue dissection. Continuous monitoring involves placing stimulation electrodes near the stylomastoid foramen and recording CMAP responses from the frontalis and orbicularis oculi/orbicularis oris muscles. The authors tested this technique in 5 patients. The authors successfully mapped the temporal branch of the FN with isolated frontalis CMAP recordings in all patients. Intraoperative FN mapping and continuous monitoring were successfully performed in all cases. Two patients experienced complete cessation of FN CMAPs, which resumed upon loosening the tension on the myocutaneous flap held by fishhooks. One patient showed a 39% decrement in frontalis CMAP that did not recover. Despite these issues, all patients had intact FN function postoperatively and at follow-up. Our technique shows promise in mitigating FN injury during complex cranial reconstruction and cranioplasty revision surgery. Further research with a larger cohort is needed to confirm efficacy and statistical significance.

Journey of frontalis muscle advancement in severe blepharoptosis: Review of the techniques, modifications, and outcomes.

We aimed to review the degree of standardization of frontalis muscle (FM)-orbicularis muscle advancement techniques in the management of severe congenital blepharoptosis and also study the evidence which supports the procedure correcting blepharoptosis. The undisputed rationale of all types of brow suspension in the management of severe blepharoptosis is based on the concept that slings are the conventional way to simultaneously suspend a ptotic eyelid and transmit the contractile action of the FM to the tarsal plate. Traditionally, frontalis suspension using sling has been used to treat patients with severe congenital blepharoptosis with poor levator function; however, postoperative lagophthalmos, forehead scarring, and recurrence remain major concerns. Since the early 80s, a significant number of consecutive articles have suggested that the eyelid can be effectively suspended by directly suturing FM to the tarsal plate. This review article intends to evaluate the level of standardization of FM advancement techniques in the management of severe blepharoptosis. 'In addition, to determine if the procedure should be performed in a standard manner, and is there enough evidence available to recommend FM advancement as a useful surgical technique.

Anatomical Trajectory of the Corrugator Supercilii Muscle in Koreans: Implications for Aesthetic and Clinical Practices.

Understanding the attachment patterns of the corrugator supercilii (CS) muscle is vital for treatments designed to improve facial symmetry and functionality. The aim of this research was to elucidate the anatomical trajectory and intricate relationships of the CS within the upper face and midface, specifically focusing on its connections with the frontalis (FT) and orbicularis oculi (OOc) muscles. The CS was examined in 41 specimens of embalmed adult Korean cadavers with microdissection, histological analyses, and microcomputed tomography, performing an in-depth exploration of its anatomical positioning and the intricate interactions with adjacent muscles. Some lower fibers of the CS extended to the upper orbital part of the OOc in 59.5% of cases, while the CS interdigitated or blended exclusively with the FT in 40.5% of cases. The fibers of the CS demonstrated diverse extensions toward the upper face and midface, exhibiting varied trajectories and lengths. Additionally, lower fibers of the CS extended to significant anatomical landmarks such as the OOc, malaris muscle, and the superficial musculoaponeurotic system (SMAS). In this study, we demonstrate that precise understanding of the CS and its relationship with the FT and OOc is crucial for optimizing invasive or noninvasive treatment like botulinum toxin injection, SMAS lifting, and browplasty surgery. The extension of lower fibers of the CS to significant anatomical landmarks indicates complex interactions with adjacent facial structures, highlighting the necessity of detailed anatomical knowledge for clinical applications.

Clinical Effect of Combined Fascia Sheath Suspension With Shortening Levator Muscle on Severe Blepharoptosis.

To study the clinical effect of conjoint fascial sheath (CFS) suspension and levator palpebrae superioris muscle shortening in the treatment of severe blepharoptosis. Forty-five patients with severe blepharoptosis (75 eyes) from May 2020 to February 2022 in the authors' hospital were divided into 2 groups: group A (n = 33, 43 eyes) and group B (n = 24, 32 eyes). Group A was operated on by CFS + levator muscle shortening, and group B was operated on by frontal muscle flap suspension + levator muscle shortening. Both groups were followed up for 12 months (until February 2023). The clinical effect was counted in 6 months after operation, the early complications were counted in 1 month after operation, and the late complications were counted in 1 month to 12 months after operation. Margin to corneal reflex distance 1 (MRD1) and palpebral fissure height (PFH) were recorded before, 1 week, 3 months, and 12 months postoperatively, and the amount of eyelid retrogression was counted again. The good correction rate was 90.70% in group A, higher than in group B (71.88%), and the difference was statistically significant (P< 0.05); the early postoperative complication rate was 9.30%, lower than in group B (24.38%), and the difference was statistically significant (P< 0.05); the late postoperative complication rate was 2.33%, lower than group B (18.75%), and the difference was statistically significant (P< 0.05). The MRD1 and PFH of group A were higher than those of group B (P< 0.05) at 3 months postoperatively and 12 months postoperatively; the MRD1 and PFH of group A were lower than those of group B (P< 0.05) at 3 months postoperatively and 12 months postoperatively. Repeated measurement analysis of variance showed that there were significant differences in the main effects of MRD1, PFH, eyelid retrogression, and time in group A and group B (P< 0.05), and there was interaction between intervention and time (P< 0.05). Conjoint fascial sheath suspension combined with levator palpebrae superioris muscle shortening can effectively improve MRD1 and PFH, and the amount of upper eyelid retraction is controllable 1 year after operation.

Anatomie de la région frontale

The forehead is an anatomic region located between the frontal hairline cranially, the eyebrow and the glabella caudally, and the anterior border of the temporal fossa laterally on both sides. Its vertical situation, due to the telencephalon growth, is specific of the human species. From surface to deep planes, the skin and sub-cutaneous fat pads are described first. The muscular plane is constituted of the frontal muscles elevators of the forehead and the eyebrow, and the depressors which are the procerus and orbicularis oculi muscles superficially, the depressor supercilii muscle, and the corrugator supercilii in a deep plane. The galea aponeurotica, located deep to the frontal muscles, is a fibrous lamina on which the muscles of the skull insert. There is a sexual dimorphism of the frontal bone. The male forehead has extensive supraorbital bossing, and above this there is often a flat area, in teh femalethe supraorbital bossing is often nonexistent and above, there is a continous mild curvature. Blood supply to the forehead is given by an anterior pedicle constituted by the supraorbital and supratrochlear vessels and a lateral pedicle made of the anterior branches from the superficial temporal vessels. The sensory innervation of the forehead is given by the ophtalmic nerve which divides in frontal, nasociliar and lacrymal nerves. The motor innervation is given by the temporal ramus of the facial nerve which passes laterally to the zygomatic arch, and gives the innervation of the frontal, corrugator supercilii and procerus muscles.

Approach to eyelid ptosis in a federal hospital in Rio de Janeiro in 2023

Introduction: The upper eyelid has complex anatomy, which is essential for an aesthetic appearance and proper function. Its normopositioning contributes to pleasant lines and is related to the eyebrow. The levator palpebrae and muller muscles maintain their height and excursion, along with the frontalis muscle. Ptosis can be congenital (myogenic or neurogenic) or acquired (myogenic, neurogenic, traumatic, mechanical, aponeurotic). The aesthetic evaluation considers the symmetry, shape and height of the eyelid. Ptosis is diagnosed when the upper eyelid margin to the reflex margin distance from the cornea is abnormally low. Eyelid fold asymmetry is associated with blepharoptosis and may require surgical correction. Methods: A total of 13 cases operated at the HFA from January to December 2023 were analyzed. All patients were approached anteriorly, with shortening of the aponeurosis of the eyelid levator muscle, after the aponeurotic defect was identified. Results: Of the cases approached (13), there were 7 men and 6 women. 11 bilateral cases and 2 unilateral cases. 1 case already operated on another service. 8 cases were elderly over 60 years old, of which 3 had a history of cataract correction (37.5%). Conclusion: The identification of ptosis in the preoperative evaluation with its consequent correction presented a better overall result, not only aesthetically, but mainly functionally. The MEPS aponeurosis shortening technique demonstrated a low complication rate, which was effective, meeting the needs of the patients and satisfying the surgeon.

Neuromodulators in Men.

Botulinum toxin treatment is gaining popularity among men for cosmetic purposes driven by workplace competition and a desire for confidence and youthfulness. Because of the unique features of male facial anatomy, careful consideration is necessary during assessment and treatment execution. The peer-reviewed literature on male facial anatomy in relation to neuromodulator treatment was analyzed with a particular emphasis on studies involving male subjects and the use of botulinum toxin type A. Anatomic differences in muscle mass and contraction patterns between men and women help guide treatment. Men appear to require higher doses for effective treatment of facial wrinkles and, in the case of glabellar lines, often require double the standard dose for women. Treatment of the frontalis muscle in men, responsible for forehead creases, requires precise dosage and placement to avoid brow ptosis. The lateral canthal wrinkles are often the first area that men seek consultation for. Although FDA approval for lower face regions is lacking, off-label use can still be considered. Successful botulinum toxin treatment in men necessitates understanding facial anatomy, customized treatment plans, and appropriate dosing. Further research is warranted to refine protocols and enhance outcomes for male patients.

Different Muscles, Lower Cutoff Values: Does it Truly Improve the Diagnostic Sensitivity of Repetitive Nerve Stimulation in Myasthenia Gravis?

ABSTRACT Context: This study evaluated the diagnostic accuracy of repetitive nerve stimulation (RNS) compared with single-fiber electromyography (SF-EMG) in generalized myasthenia gravis (MG). Aims: The aim of the study was to determine the diagnostic sensitivity of RNS in various muscles and assess the effect of varying decrement cutoff values on diagnostic efficacy. Setting and Design: This was a prospective study of 34 confirmed generalized MG patients. Subjects and Methods: RNS was performed on five muscles. Clinical features, autoantibody presence, and SF-EMG jitter rates recorded from the frontalis muscle were analyzed. Patients were classified according to the MG Foundation of America classification. Statistical Analysis: SPSS version 23 was used for descriptive statistics, comparisons of categorical and quantitative data, and correlation analysis, with the significance level set at P &lt; 0.05. Results: Among the patients (58.8% males and mean age = 59.47 ± 13.37 years), SF-EMG detected increased jitter in 91.2%, whereas RNS identified a significant decrease of 50% across at least one muscle. The decremental response was &gt;10% in the abductor digiti minimi (ADM), trapezius, nasalis, abductor pollicis brevis, and extensor indicis proprius muscles in 5.9%, 26.5%, 29.4%, 11.8%, and 29.4% of patients, respectively. A sensitivity improvement at lower decrement values was observed only in the ADM muscle. A significant correlation was found between decreases in the trapezius muscle and seropositivity. Conclusions: Optimal muscle selection improves RNS diagnostic accuracy in MGs. The study recommends incorporating the spinal accessory and radial nerves in RNS due to their high sensitivity, although modifying the decrement cutoff value has a limited overall effect.