Toxin Treatment Research Articles

Resolving the Controversy Surrounding the Function of the Corrugator Supercilii Muscle.

The corrugator supercilii muscle (CSM) has traditionally been recognized as a primary depressor of the eyebrows, playing a key role in expressing negative emotions and contributing to the formation of glabellar lines. However, recent studies indicate that the CSM may exhibit movements contrary to those previously documented, suggesting a more complex functional role. This research re-evaluates the anatomical and functional roles of the CSM and discusses their implications for botulinum toxin treatments. A prospective, intrapersonal comparative, and split-face study was conducted over a five-year period, from January 6, 2019, to January 6, 2024, involving 298 patients who underwent botulinum toxin injections. The study divided participants into seven groups, each targeting specific anatomical areas of the CSM and associated muscles. Injection techniques were varied to assess their impact on brow dynamics, with outcomes measured by changes in eyebrow position and expression lines. The study demonstrated that targeting specific portions of the CSM and depressor supercilii muscle (DSM) leads to distinct outcomes in brow elevation and the reduction of expression lines. However, this approach was also frequently associated with the development of omega-shaped wrinkles. Split-face evaluations further validated that the modified injection techniques achieved superior eyebrow elevation compared to traditional methods. This study challenges the traditional view of the CSM as primarily a brow depressor, highlighting its role in medial brow elevation. These findings underscore the need for a nuanced approach in esthetic medicine, particularly in botulinum toxin injections, to achieve balanced and natural facial expressions. Understanding the full range of CSM functions is crucial for optimizing esthetic outcomes and enhancing patient satisfaction. 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 .

Botulinum Toxin Treatment of Psoriasis-A Comprehensive Review.

A literature search on the subject of botulinum toxin treatment in psoriasis found 15 relevant articles, 11 on human subjects and 4 on animal studies. Of the human data, eight were clinical trials and three were single case reports. Seven out of eight clinical trials, all open-label, reported improvement in psoriasis following intradermal or subcutaneous botulinum toxin injections. One double-blind, placebo-controlled study, which used a smaller dose than the open-label studies, did not note a healing effect. Animal studies have shown that injection of botulinum toxins in the skin heals psoriatic skin lesions and can reduce the level of interleukins (ILs) and cytokines as well as inflammatory cells in psoriatic plaques. There is a need for controlled, blinded studies conducted in larger numbers of patients with doses that have shown promise in open-label studies.

Predisposing factors to pattern change in cervical dystonia.

Cervical dystonia (CD) patterns may change with Botulinum toxin (BoNT) treatment. To evaluate the time within those changes usually occur, the most predisposed phenotypes and predisposing factors. We divided idiopathic CD patients into two groups- change YES and NO, collecting general clinical and demographic variables. We also evaluated duration of BoNT treatment, Tsui total scores and subscores - assessed at T0 - before BoNT start - and at T1- time to chenge in the YES group or last visit in the NO group. The risk of pattern change was assessed by Kaplan Meyer curves and Cox regression analysis. Finally, Multivariate linear regressions were employed to assess if Tsui severity correlated with the change. Among 100 patients (60 women), 37 experienced a phenotype switch, mostly in the first five years of BoNT treatment, YES and NO groups were comparable. Multivariate Cox Regression revealed the presence of laterocollis or rotatocollis at T0 as predictors of switch (respectively P = 0.01, HR = 3.5; P = 0.03, HR = 1.5). Multivariate linear regressions revealed that high Tsui subscores for the tilt and low Tsui total scores were risk factors for the change of pattern (respectively P = 0.002, OR = 6; P = 0.03, OR = 0.8). Latero and Rotatocollis are the CD phenotypes most predisposed to change. CD characterized by neck tilt are more likely to change phenotype following treatment. Dystonias with a low degree of severity are more predisposed to switch. Both, the different degree of muscle activation and BoNT mechanism of action, may impact on that phenomenon.

Selective depletion of kisspeptin neurons in the hypothalamic arcuate nucleus in early juvenile life reduces pubertal LH secretion and delays puberty onset in mice.

Puberty is the critical developmental transition to reproductive capability driven by the activation of gonadotropin-releasing hormone (GnRH) neurons. The complex neural mechanisms underlying pubertal activation of GnRH secretion still remain unknown, yet likely include kisspeptin neurons. However, kisspeptin neurons reside in several hypothalamic areas and the specific kisspeptin population timing pubertal onset remains undetermined. To investigate this, we strategically capitalized on the differential ontological expression of the Kiss1 gene in different hypothalamic nuclei to selectively ablate just arcuate kisspeptin neurons (aka KNDy neurons) during the early juvenile period, well before puberty, while sparing RP3V kisspeptin neurons. Both male and female transgenic mice with a majority of their KNDy neurons ablated (KNDyABL) by diphtheria toxin treatment in juvenile life demonstrated significantly delayed puberty onset and lower peripubertal LH secretion than controls. In adulthood, KNDyABL mice demonstrated normal invivo LH pulse frequency with lower basal and peak LH levels, suggesting that only a small subset of KNDy neurons is sufficient for normal GnRH pulse timing but more KNDy cells are needed to secrete normal LH concentrations. Unlike prior KNDy ablation studies in rats, there was no alteration in the occurrence or magnitude of estradiol-induced LH surges in KNDyABL female mice, indicating that a complete KNDy neuronal population is not essential for normal LH surge generation. This study teases apart the contributions of different kisspeptin neural populations to the control of puberty onset, demonstrating that a majority of KNDy neurons in the arcuate nucleus are necessary for the proper timing of puberty in both sexes.

Botulinum Toxin Treatment in a Patient with Facial Paralysis

Botulinum Toxin Treatment in a Patient with Facial Paralysis

Pelvic floor muscle electrical coupling in chronic pelvic pain: Insights into pathophysiology and botulinum toxin treatment effects

This study aimed to assess the electrical coupling between both pelvic floor muscle (PFM) sides (two-sided coupling) and within individual PFM sides (one-sided coupling) in chronic pelvic pain (CPP) before and after botulinum neurotoxin type A (BoNT/A) treatment. Surface electromyographic (sEMG) signals were recorded from the left and right PFM of 24 patients (P) with CPP before and after being treated with BoNT/A (Weeks 0,8,12,24). Recordings were also made in 24 healthy women (H). PFM two-sided and one-sided coupling was evaluated during contractions by the cross-correlation (CC) and the imaginary part of coherency (iCOH) of their sEMG signals. Significant differences between their values were assessed comparing P(0) vs. P(8,12,24) and H vs. P(0,8,12,24). This study showed that PFM two-sided coupling is similar across groups before treatment, while PFM one-sided coupling on the patients’ most painful side is deranged before and also after BoNT/A treatment: amplitude coupling is lower (<CC) and phase difference is greater (>iCOH) than healthy women’s. This could be justified by altered neuromotor control strategies developed as an adaptation to muscle pain, structural and electrical changes in PFM, and alterations in their innervation pattern, which may influence the onset, perpetuation, or recurrence of CPP after treatment.

Mitigating adverse effects in botulinum toxin treatments: Best practices and key findings

Botulinum toxin, commonly known as Botox, is extensively used in both aesthetic and medical procedures due to its effectiveness in reducing wrinkles and treating conditions like cervical dystonia and hyperhidrosis. Despite its general safety, the use of botulinum toxin carries risks of adverse effects. Common immediate side effects include bruising, swelling, and pain at the injection site, which are usually mild and resolve within a few days. However, more serious complications, such as blepharoptosis (drooping eyelids), brow ptosis, and ocular sensory dysfunction, can occur and significantly impact facial expression and ocular function. Rare but severe adverse events include systemic spread of the toxin, leading to generalized muscle weakness and respiratory issues. These serious reactions require prompt medical attention and may be exacerbated by excessive doses or improper techniques. Long-term concerns include the formation of neutralizing antibodies, potentially reducing treatment effectiveness and altering facial dynamics over time. To minimize risks, it is crucial to select a qualified professional with experience in botulinum toxin administration, use precise injection techniques, and adhere to the smallest effective doses. Thorough patient evaluations and education about potential adverse effects and post-treatment care are essential. Regular monitoring and follow-ups help detect and address adverse effects promptly, with adjustments based on individual patient responses. Studies highlight the importance of these practices: Sethi et al. (2020) noted common adverse effects, Sorensen and Urman (2015) identified both common and rare complications, and Lee et al. (2020) linked serious outcomes to patient-specific factors. Coté et al. (2005) emphasized adherence to guidelines, while Witmanowski and Błochowiak (2019) discussed the distinction between benign and serious events. Laet and Wyndaele (2005) focused on rare generalized side effects in specific contexts.

The Goal Attainment Scale Refines Patient-Centered Expectations in Botulinum Toxin Treatment of Cervical Dystonia.

The Goal Attainment Scale Refines Patient-Centered Expectations in Botulinum Toxin Treatment of Cervical Dystonia.

A Retrospective Study on Botulinum Toxin Injection in Patients With Multiple Sclerosis Related Tremor: A Treatment Option Worth Trying

Objectives Multiple sclerosis (MS)-related tremor remains a disabling problem that often responds poorly to medical treatments. This study aims to evaluate the effect of botulinum toxin type A on MS-related upper limb tremor. Methods This retrospective observational cohort study included 8 patients who received intramuscular injections of onabotulinum toxin type A for medically refractory MS-related tremor. Hospital records before and 4–6 weeks after treatment, including the Fahn-Tolosa-Marin Tremor rating scale (FTM-TRS), electrophysiological tremor analysis, neurological examination findings, and videos, were reviewed retrospectively. Results There was significant improvement after botulinum toxin injection in the FTM TRS part A score for tremor (P = 0.011), FTM TRS part B score for hand function (P = 0.011), FTM Part score for activities of daily living (P = 0.012), and FTM TRS total score for overall evaluation (P = 0.012). Electrophysiological tremor analysis revealed maximal tremor amplitudes between 700–2000 μV (before treatment) and between 300–1000 μV (after treatment). The mean tremor amplitudes before and after treatment were 1350 μV and 725 μV, respectively. No adverse reactions were observed after botulinum toxin treatment. Conclusions BoNT may improve upper limb tremor and functionality in MS-related tremor. The treatment involved administering BoNT under EMG guidance, with careful muscle selection based on clinical assessment and EMG findings. This approach aimed to optimize treatment efficacy while minimizing potential adverse effects. Further studies are warranted to confirm these findings.

Antipsychotics and chronic dystonia at a Botulinum Toxin clinic.

Chronic dystonia, characterised by sustained muscle contractions and abnormal postures, poses clinical challenges, especially when associated with antipsychotic medication use. To delineate the demographic and clinical profiles of adults with dystonia and examine the association with antipsychotic medication. Botulinum Toxin Clinic at Tygerberg Hospital, Cape Town, South Africa. We conducted a retrospective cohort study of adult patients seen at the Botulinum Toxin Clinic between January 2018 and June 2022. Of the 119 patients studied, those assessed with antipsychotic-induced dystonia (32.69%) presented at a younger age (p < 0.001), were more likely female (p = 0.04), received higher average dose of Botulinum toxin (p < 0.001), and incurred a higher estimated Botulinum toxin treatment cost (p = 0.01) compared to those with primary dystonia. Logistic regression identified age and Botulinum toxin dose as factors associated with psychotropic-related dystonia (p = 0.005 and p = 0.012, respectively). Clinical and demographic factors are associated with dystonia in adults taking antipsychotic medication. These patients generally manifested symptoms at an earlier age, had a higher male prevalence, and required prolonged treatment with Botulinum toxin, leading to increased costs. In those assessed with antipsychotic-induced dystonia, a comorbid diagnosis of a mood disorder was more common than that of a psychotic disorder. By identifying the demographic and clinical profile of individuals with dystonia because of antipsychotic medication, this study provides a basis for preventative strategies and enhanced patient care.

Mitigating Immunogenicity by Coordinating Botulinum Toxin Treatments Between Aesthetics and Therapeutics.

Aesthetic use of botulinum toxin (BoNT) has expanded greatly beyond conventional low-dose (20 U) treatments, leading to some patients receiving doses previously reserved for therapeutic uses. The resulting risks are compounded in patients who receive BoNT for both aesthetic and therapeutic indications. Implementing tools for risk management is a high priority to prevent reduced treatment duration and effectiveness. To highlight the immunogenic risks of higher doses, with special attention to the compounding risks of resistance in patients with overlapping BoNT treatments from aesthetic and therapeutic indications. Authors examined the literature on current practices to provide a side-by-side comparison of BoNT doses for aesthetic and therapeutic indications. Aesthetic BoNT doses used in combination treatments of multiple areas or single treatments of large muscle areas can meet or exceed those observed in therapeutic treatments. Physicians have a responsibility to incorporate risk management and open dialog into their BoNT treatment plans to maximize effectiveness and longevity of treatments.

Evaluating Headache Incidence and Characteristics After Botulinum Toxin Treatment in Blepharospasm and Hemifacial Spasm Patients: A Retrospective Cohort Clinical Study.

The aim of the study is to assess the prevalence and clinical features of headache in patients treated with botulinum toxin for blepharospasm and hemifacial spasm. In addition, our secondary aim was to identify potential factors influencing the development of these headaches. A total of 70 patients who were treated with on a botulinum toxin A for dystonia treatment in our clinic between January 2023 and March 2023 were retrospectively screened, and the clinical and demographic characteristics of the patients who reported headache complaints after the last botulinum toxin treatment were examined. Headache was reported in 8 (%11.4) of the 70 patients included in the study. Of the 8 patients who reported headaches, 6 (%75) had the onset of the complaint within the first 24 hours. There was no significant correlation between headache occurrence and factors like age, gender, diagnosis, botulinum toxin dosage, application site, comorbid diseases, or hypertension. However, a statistically significant link was observed between the intensity of pain experienced during treatment and the frequency of headaches after the treatment. Botulinum toxin treatment can lead to short-term headaches in some patients, starting early after the procedure. The significant link between the frequency of these headaches and the pain experienced during injection highlights the need to examine factors like the volume and dilution rate of the toxin, the solvent used, treatment area, treatment purpose, patient characteristics, and the physician's technique. It is important to study these aspects by comparing them across a large patient group and control subjects.

Classification of upper limb spasticity patterns in patients with multiple sclerosis: a pilot observational study.

The aim of this study was to provide a classification of the upper limb patterns in patients with upper limb spasticity due to multiple sclerosis. Pilot observational study. Twenty-five adult patients with multiple sclerosis suffering from upper limb spasticity who underwent one segmental (i.e., proximal and distal upper limb) botulinum toxin treatment cycle were recruited. Patients remained in a sitting position during the evaluation. Upper limb spasticity postures (i.e., postural attitude of a single joint/anatomical region) were evaluated and recorded for the shoulder (adducted/internally rotated), elbow (flexed/extended), forearm (pronated/supinated/neutral), wrist (flexed/extended/neutral) and hand (fingers flexed/thumb in palm). On the basis of the clinical observations, 6patterns (i.e., sets of limb postures) of upper limb spasticity have been described according to the postures of the shoulder, elbow, forearm, and wrist. The patterns of upper limb spasticity in patients with multiple sclerosis described by this pilot study do not completely overlap with those observed in patients with post-stroke spasticity. This further supports the need to consider the features of spasticity related to its aetiology in order to manage patients appropriately.

Botulinum toxin treatment for hemifacial spasm: harmonising neurological and aesthetic outcomes.

Hemifacial spasm (HFS) represents a challenging cranial movement disorder primarily affecting the facial nerve innervated muscles, with significant prevalence among Asians. Botulinum toxin type A (BoNT/A) injections, established as a primary therapeutic intervention since FDA approval, offer considerable effectiveness in alleviating spasms, albeit accompanied by challenges such as temporary effects and potential adverse events including facial asymmetry. This comprehensive review underscores the crucial need for harmonising neurological benefits and aesthetic outcomes in HFS management. The discussion delves into the interplay between facial aesthetics and neurological objectives in BoNT/A injections, emphasising precise techniques, dosages, and site considerations. Distinct aspects in neurological and aesthetic domains are also examined, including detailing the targeted muscles and injection methodologies for optimal therapeutic and aesthetic results. Importantly, evidence regarding various BoNT/A formulations, recommendations, and reconstitution guidelines in both neurology and aesthetics contexts are provided, along with a schematic approach outlining the stepwise process for BoNT/A injection in HFS treatment, addressing critical areas such as orbicularis oculi muscle sites, eyebrow correction strategies, mid- and lower-face considerations, contralateral injection sites, and post-injection follow-up and complication management. By highlighting the culmination of neurological efficacy and facial esthetics in BoNT/A treatment for HFS patients, this review proposes a holistic paradigm to achieve balanced symptomatic relief and natural aesthetic expression, ultimately enhancing quality of life for individuals grappling with HFS.

Phase-Based Gait Prediction after Botulinum Toxin Treatment Using Deep Learning.

Gait disorders in neurological diseases are frequently associated with spasticity. Intramuscular injection of Botulinum Toxin Type A (BTX-A) can be used to treat spasticity. Providing optimal treatment with the highest possible benefit-risk ratio is a crucial consideration. This paper presents a novel approach for predicting knee and ankle kinematics after BTX-A treatment based on pre-treatment kinematics and treatment information. The proposed method is based on a Bidirectional Long Short-Term Memory (Bi-LSTM) deep learning architecture. Our study's objective is to investigate this approach's effectiveness in accurately predicting the kinematics of each phase of the gait cycle separately after BTX-A treatment. Two deep learning models are designed to incorporate categorical medical treatment data corresponding to the injected muscles: (1) within the hidden layers of the Bi-LSTM network, (2) through a gating mechanism. Since several muscles can be injected during the same session, the proposed architectures aim to model the interactions between the different treatment combinations. In this study, we conduct a comparative analysis of our prediction results with the current state of the art. The best results are obtained with the incorporation of the gating mechanism. The average prediction root mean squared error is 2.99° (R2 = 0.85) and 2.21° (R2 = 0.84) for the knee and the ankle kinematics, respectively. Our findings indicate that our approach outperforms the existing methods, yielding a significantly improved prediction accuracy.

The role of BTG2/PI3K/AKT pathway-mediated microglial activation in T-2 toxin-induced neurotoxicity

T-2 toxin is one of the mycotoxins widely distributed in human food and animal feed. Our recent work has shown that microglial activation may contribute to T-2 toxin-induced neurotoxicity. However, the molecular mechanisms involved need to be further clarified. To address this, we employed high-throughput transcriptome sequencing and found altered B cell translocation gene 2 (BTG2) expression levels in microglia following T-2 toxin treatment. It has been shown that altered BTG2 expression is involved in a range of neurological pathologies, but whether it’s involved in the regulation of microglial activation is unclear. The aim of this study was to investigate the role of BTG2 in T-2 toxin-induced microglial activation. The results of animal experiments showed that T-2 toxin caused neurobehavioral disorders and promoted the expression of microglial BTG2 and pro-inflammatory activation of microglia in hippocampus and cortical, while microglial inhibitor minocycline inhibited these changes. The results of in vitro experiments showed that T-2 toxin enhanced BTG2 expression and pro-inflammatory microglial activation, and inhibited BTG2 expression weakened T-2 toxin-induced microglial activation. Moreover, T-2 toxin activated PI3K/AKT and its downstream NF-κB signaling pathway, which could be reversed after knock-down of BTG2 expression. Meanwhile, the PI3K inhibitor LY294002 also blocked this process. Therefore, BTG2 may be involved in T-2 toxin's ability to cause microglial activation through PI3K/AKT/NF-κB pathway.

Tibial Damage Caused by T-2 Toxin in Goslings: Bone Dysplasia, Poor Bone Quality, Hindered Chondrocyte Differentiation, and Imbalanced Bone Metabolism.

T-2 toxin, the most toxic type A trichothecene, is widely present in grain and animal feed, causing growth retardation and tissue damage in poultry. Geese are more sensitive to T-2 toxin than chickens and ducks. Although T-2 toxin has been reported to cause tibial growth plate (TGP) chondrodysplasia in chickens, tibial damage caused by T-2 toxin in geese has not been fully demonstrated. This study aims to investigate the adverse effects of T-2 toxin on tibial bone development, bone quality, chondrocyte differentiation, and bone metabolism. Here, forty-eight one-day-old male Yangzhou goslings were randomly divided into four groups and daily gavaged with T-2 toxin at concentrations of 0, 0.5, 1.0, and 2.0 mg/kg body weight for 21 days, respectively. The development of gosling body weight and size was determined by weighing and taking body measurements after exposure to different concentrations of T-2 toxin. Changes in tibial development and bone characteristics were determined by radiographic examination, phenotypic measurements, and bone quality and composition analyses. Chondrocyte differentiation in TGP and bone metabolism was characterized by cell morphology, tissue gene-specific expression, and serum marker levels. Results showed that T-2 toxin treatment resulted in a lower weight, volume, length, middle width, and middle circumference of the tibia in a dose-dependent manner (p < 0.05). Moreover, decreased bone-breaking strength, bone mineral density, and contents of ash, Ca, and P in the tibia were observed in T-2 toxin-challenged goslings (p < 0.05). In addition, T-2 toxin not only reduced TGP height (p < 0.05) but also induced TGP chondrocytes to be disorganized with reduced numbers and indistinct borders. As expected, the apoptosis-related genes (CASP9 and CASP3) were significantly up-regulated in chondrocytes challenged by T-2 toxin with a dose dependence, while cell differentiation and maturation-related genes (BMP6, BMP7, SOX9, and RUNX2) were down-regulated (p < 0.05). Considering bone metabolism, T-2 toxin dose-dependently and significantly induced a decreased number of osteoblasts and an increased number of osteoclasts in the tibia, with inhibited patterns of osteogenesis-related genes and enzymes and increased patterns of osteoclast-related genes and enzymes (p < 0.05). Similarly, the serum Ca and P concentrations and parathyroid hormone, calcitonin, and 1, 25-dihydroxycholecalciferol levels decreased under T-2 toxin exposure (p < 0.05). In summary, 2.0 mg/kg T-2 toxin significantly inhibited tibia weight, length, width, and circumference, as well as decreased bone-breaking strength, density, and composition (ash, calcium, and phosphorus) in 21-day-old goslings compared to the control and lower dose groups. Chondrocyte differentiation in TGP was delayed by 2.0 mg/kg T-2 toxin owing to cell apoptosis. In addition, 2.0 mg/kg T-2 toxin promoted bone resorption and inhibited osteogenesis in cellular morphology, gene expression, and hormonal modulation patterns. Thus, T-2 toxin significantly inhibited tibial growth and development with a dose dependence, accompanied by decreased bone geometry parameters and properties, hindered chondrocyte differentiation, and imbalanced bone metabolism.

Creating a novel method for chicken primordial germ cell health monitoring using the fluorescent ubiquitination-based cell cycle indicator reporter system

The most current in vitro genetic methods, including gene preservation, gene editing and developmental modelling, require a significant number of healthy cells. In poultry species, primordial germ cells (PGCs) are great candidates for all the above-mentioned purposes, given their easy culturing and well-established freezing method for chicken. However, the constant monitoring of cultures can be financially challenging and consumes large amounts of solutions and accessories. This study aimed to introduce the Fluorescent Ubiquitination-based Cell Cycle Indicator (FUCCI) complex into the chicken PGCs. FUCCI is a powerful transgenic tool based on the periodic protein expression changes during the cell cycle. It includes chromatin licensing and DNA replication factor 1 attached monomeric Kusabira-Orange and Geminin-attached monomeric Azami-Green fluorescent proteins, that cause the cells to express a red signal in the G1 phase and a green signal in S and G2 phases. Modification of the chicken PGCs was done via electroporation and deemed to be successful according to confocal microscopy, DNA sequencing and timelapse video analysis. Stable clone cell lines were established, cryopreserved, and injected into recipient embryos to prove the integrational competency. The cell health monitoring was tested with medium change experiments, that proved the intended reactions of the FUCCI transgene. These results established the future for FUCCI experiments in chicken, including heat treatment and toxin treatment.

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

Botulinum toxin A (BoNT-A) treatment has many uses in dermatology. Its mechanism of action and long-term effects for scar formation, rosacea, and antiaging are still being investigated. To conduct a literature review on BoNT-A to further investigate its use in scar formation, rosacea, and antiaging. A literature review was conducted using PubMed on botulinum toxin treatment for scar formation, rosacea, and antiaging. Studies discussing the toxin mechanism of action and treatment algorithm were included. The authors also provided their personal experience in BoNT-A use for these 3 conditions. The mechanism of action of Botulinum toxin A in improving scar formation, rosacea, and antiaging is now better understood. While it is effective in the short term, little is still known about how frequently treatment needs to be repeated and if there are any long-term effects. While in vitro studies have supporting evidence on the mechanism of action of BoNT-A on scar formation, rosacea, and antiaging, further studies are needed to identify long-term treatment effects.

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.