Sonoanatomy of injecting botulinum neurotoxin into the facial muscles.

INTRODUCTION: Ultrasonography (US) has become an essential tool for guiding botulinum neurotoxin (BoNT) injections in facial muscles, enhancing precision and safety. This narrative review explores the role of US in BoNT administration, particularly in complex anatomical regions, highlighting its impact on treatment customization, real-time visualization, and complication reduction. MATERIALS AND METHODS: A comprehensive literature search was conducted using PubMed, MEDLINE, Embase, and Cochrane Library for articles published from January 2018 to December 2023. Search terms included "Botulinum neurotoxin," "facial anatomy," "ultrasonography guided injection," and "facial muscle sonoanatomy." Studies focusing on US-guided BoNT injections in facial muscles were included. Data extraction and synthesis were performed independently by two reviewers, focusing on study design, ultrasonography techniques, outcomes, and conclusions. RESULTS: The review found that US guidance significantly enhances the precision of BoNT injections by providing real-time visualization of facial muscles and blood vessels, thereby reducing the risk of adverse events. US enables tailored injection strategies, ensuring symmetrical facial expressions and minimizing over-treatment. The technique also offers immediate feedback, allowing for on-the-spot adjustments to improve treatment efficacy and safety. However, the review identified limitations, including potential selection bias and variability in US techniques across different studies. CONCLUSION: US guidance for BoNT injections into facial muscles offers substantial benefits in terms of precision, safety, and treatment customization. Despite the identified limitations, the integration of US into clinical practice is poised to enhance patient outcomes in aesthetic and therapeutic procedures. Further research is needed to standardize US techniques and broaden the inclusivity of studies to validate these findings comprehensively.

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.

Deciphering Depressor Anguli Oris for Lower Face Rejuvenation: A Prospective Ultrasound-based Investigation.

BACKGROUND: The depressor anguli oris muscle (DAO) is a pivotal treatment target when creating a harmonic jawline. However, evidence of its live morphology remains scarce. OBJECTIVES: In this study we aimed to reevaluate the DAO with a facile ultrasound analysis and thereby guide safer and more effective botulinum toxin type A (BTX-A) injection. METHODS: A prospective ultrasound assessment was conducted in 41 patients. Morphology of the DAO and its relative position to neighboring structures were appraised at the ubiquitous facial landmark, the labiomandibular fold (LMF). Three-dimensional images were captured before and after the patient received the BTX-A injection based on sonographic evidence. RESULTS: The skin-to-muscle depths of the DAO on average (measured from the medial to lateral border) were 5.26, 5.61, and 8.42 mm. The DAO becomes thinner and wider from zone 1 to zone 3 (P < .001). Overlapping lengths of the DAO and the depressor labii inferioris increased from zone 1 to zone 3: 4.74, 9.68, 14.54 mm (P < .001). The medial border of the DAO was located at 4.33, 6.12, 8.90 mm medial to the LMF (zone 1-3), and no muscle fibers of the DAO were observed in zone 1 or zone 2 in nearly one-third of patients. Improvement of the mouth corner downturn angle upon receiving BTX-A injection at zones 2 and 3 were 88.3%, 32.3%, and 14.7% for the neutral, maximum smile, and down-turning mouth corner expressions. CONCLUSIONS: This work established an informative ultrasound portrait of the DAO and structures in the perioral region, which suggested the LMF as a convenient landmark for locating the DAO. Injection at the middle and lower thirds of the LMF at a 4- to 5-mm depth is recommended.

Advanced Injection of Botulinum Toxin in the Nasal Muscles: A Novel Dynamic Change in Facial Expression.

BACKGROUND: Among the nasal muscles, the levator labii superior alaeque nasi (LLSAN) acts as a transitional muscle that conjugates with other nasal and perinasal muscles. Thus, when treating the nasal region with Botulinum toxin (BTX), it is important to understand local nasal muscular dynamics and how they can influence the muscular dynamics of the entire face. METHODS: This is a retrospective analysis of cases treated by an injection pattern encompassing the face, including nasal muscles. Photographs were taken at rest and during motion (frontal and oblique views), before and after treatment. RESULTS: A total of 227 patients have been treated in the last 18 months with the following results: eyebrow tail lifting, softness of crow's feet, improvement of the drooping of the tip of the nose, and shortening of the lip philtrum when smiling. We present cases illustrating the use of this approach. CONCLUSIONS: Treating the facial muscles globally (including the frontal, corrugators, procerus, orbicularis oculi, platysma, DAO, and nasal muscles) can improve the smile and facial expressions. This is believed to occur because the elevated portion of the upper lip muscle becomes stronger as the nasal part of the LLSAN is paralyzed. LEVEL OF EVIDENCE IV: 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 .

Application of 3-Dimensional Technology for Evaluating Muscular Type and Muscle-Fat Pad Mixed-Type Nasolabial Folds With Botulinum Toxin-A Treatment.

BACKGROUND: Botulinum toxin-A (BTX-A) is used in the treatment of nasolabial folds (NLFs). However, lighting and clinician subjectivity play a major role in evaluating the efficacy of this treatment. OBJECTIVES: By applying 3-dimensional (3D) technology, this study aimed to quantitatively evaluate the effects of BTX-A injection on muscular (M) and muscle-fat pad mixed-type (MF) NLFs. METHODS: BTX-A was injected into bilateral marked points on the NLFs, where the levator labii alaeque nasi, zygomaticus minor, and zygomaticus major pull the skin to form the NLF (2 U at each injection site). Pretreatment and posttreatment 3D facial images were captured with static and laughing expressions. The curvature, width, depth, and lateral fat volume of the NLFs were measured to compare the therapeutic efficacy for type M and MF NLFs. RESULTS: Thirty-nine patients with type M and 37 with type MF NLFs completed the follow-up data. In these patients, the curvature, width, and depth of the NLF showed a significant reduction at 1 month and gradually recovered at 3 and 6 months after treatment, with more significant improvement when laughing than when static. Variations compared to the pretreatment values of type MF were greater than those of type M at each time point. The lateral fat volume of the type MF NLF was significantly reduced (P < .05). CONCLUSIONS: 3D technology can quantitatively evaluate the effects BTX-A injection for treating type M and type MF NLFs. BTX-A is more effective on type MF than on type M NLFs.

Botulinum Toxin Type A Injection in the Treatment of Postparetic Facial Synkinesis: An Integrative Review.

ABSTRACT: This study aimed to review the recent literature about botulinum toxin type A treatment patterns, including muscle targets, doses, duration of effect, adverse effects, and clinical outcomes in patients with postparetic synkinesis. A bibliographic research of studies published in the last 10 yrs was carried out on PubMed database, using the medical subject heading terms: botulinum toxin and synkinesis. English-language cohort studies or randomized controlled trials about botulinum toxin type A treatment on patients with postparetic synkinesis were eligible for inclusion. Ten studies met the inclusion criteria, seven prospective studies, two retrospective studies, and one randomized controlled trial, involving 23-99 patients. The target facial muscles included frontalis, corrugator supercilli, orbicularis oculi, levator labii superioris, zygomaticus major, orbicularis oris, risorius, buccinator, depressor anguli oris, depressor labii inferioris, mentalis, and platysma. The dose of onabotulinumtoxinA administered per injection site ranged between 0.5 and 10 U. Adverse effects were rare and temporary. The mean duration of onabotulinumtoxinA effect ranges from 66 days to 4 mos. There was a statistically significant improvement in posttreatment evaluation, both in objective and subjective assessments. There is scientific evidence of the benefit of botulinum toxin type A treatment for postparetic synkinesis, but there is lack of standardized treatment protocols.

Forehead Movement Discrepancies After Botulinum Toxin Injections: A Review of Etiology, Correction, and Prevention.

BACKGROUND: Forehead rhytides are a popular target for botulinum toxin injections, but neuromodulation of the frontalis can be fraught with complications because of its anatomic complexity and integral role in brow position and expressivity. OBJECTIVE: This article explores common forehead movement discrepancies that can occur after neuromodulation of the frontalis, as well as how to correct and prevent them. METHODS: A review of the literature was conducted and combined with clinical experience to examine underlying forehead anatomy, etiology and correction of forehead movement discrepancies, and important factors to consider before injecting the frontalis with botulinum toxin. RESULTS AND CONCLUSION: Variable anatomy from person to person necessitates an individualized treatment approach to achieve the best cosmetic results and prevent the occurrence of forehead movement discrepancies.

Postmarketing safety surveillance data reveals protective effects of botulinum toxin injections against incident anxiety.

Randomized controlled trials (RCTs) have shown an antidepressant effect of glabellar botulinum toxin (BoNT) injections. In the FDA Adverse Event Reporting System (FAERS) database, BoNT injection is associated with reduced incidence rates of depression across various non-psychiatric indications, which confirms the previous findings independently of specific expectations to an antidepressant effect of BoNT. The rationale of using BoNT to treat depression is to interrupt proprioceptive body feedback that may reinforce negative emotions. Negative emotions also occur in other mental disorders, suggesting a transdiagnostic therapeutic potential of BoNT in psychiatry. Here we report an analysis of the FAERS database, in which we found that, compared to alternative treatments, BoNT injections were associated with lower incidence of anxiety symptoms and related disorders. Among seven indications/injection sites, we found this protective effect of BoNT in cosmetic use/facial muscles, migraine/facial and head muscles, spasms and spasticity/upper and lower limbs, torticollis and neck pain/neck muscles, and sialorrhea/parotid and submandibular glands (reporting odds ratios 0.79-0.27). These findings are encouraging for possible future RCTs on the use of BoNT as a treatment for anxiety and related disorders.

Targeted chemodenervation of the posterior belly of the digastric muscle for the management of jaw discomfort in facial synkinesis.

BACKGROUND: Botulinum toxin (BT-A) chemodenervation has been proved to significantly improve the physical and psychological well-being of patients suffering from facial synkinesis. Despite this, a cohort of patients has persistent tightness and discomfort around the angle of the jaw, which may be caused by synkinesis within the posterior belly of digastric (PBD) muscle. This study was designed to evaluate the benefits of ultrasound-guided BT-A injections into the PBD. METHODS: Thirty-three patients with recalcitrant tightness and discomfort around the angle of the jaw, despite maximal facial therapy and platysmal chemodenervation were selected for inclusion. Patients underwent ultrasound-guided BT-A injection into the ipsilateral PBD muscle (skin puncture site 1 cm inferior and posterior to the angle of mandible). Outcomes consisted of the Facial Disability Index (FDI), Synkinesis Assessment Questionnaire (SAQ), and a visual analogue scale (VAS) designed to assess tightness and pain around the PBD when moving the jaw, swallowing, and masticating. Questionnaires were completed two weeks before and postinjection. Statistical analysis was performed using a paired t-test. RESULTS: Nineteen patients completed the post-treatment outcome questionnaire. A statistically significant improvement was noted in the physical and social function aspects of the FDI and all aspects of the patient-reported VAS scores apart from tightness and pain on jaw retrusion and swallowing. There was no significant difference in the SAQ. CONCLUSION: This study has demonstrated the patient-perceived benefit of ultrasound-targeted BT-A chemodenervation of PBD. This represents a low-risk treatment option that can be easily added to the repertoire of treatments offered to patients with post paralysis facial synkinesis.

Three-dimensional measurement and analysis of botulinum toxin A injection for improving the aesthetic appearance of upper lip.

This study evaluated the efficacy of botulinum toxin A (BTX A) in improving the aesthetic appearance of lips. Twenty-four outpatients with clinical evidence indicating decreased fullness of lips or gummy smile were selected and received BTX A injection on the orbicularis oris. We observed a significant decrease in wrinkles and improvement in gummy smile in all patients 4 weeks after the injection. Aesthetic lines also changed significantly. Local injection of BTX A on the orbicularis oris could simultaneously achieve mild lip enhancement, improvement in fine wrinkles around lips, and mild gummy smile.

Long-term stable efficacy of botulinum toxin A in facial movement disorders with no need for increasing dose.

ABSTRACT: Botulinum toxin A is considered an effective treatment for involuntary facial movements. We examined whether treatment efficacy maintained or changed over time with two products, Botox and Dysport, in patients with hemifacial spasm, facial synkinesis and benign essential blepharospasm.We retrospectively investigated 87 consecutive patients (51 women, 36 men) who had undergone treatment for ≥6 years. Long-term effects, as well as side effects of Botox or Dysport local injections were evaluated. The first three treatments were considered the titration period and not taken into account when testing for dose changes.Mean treatment duration was 10 years (range 6-11, SD 1.0), 2441 treatments were administered, 1162 with Botox and 1279 with Dysport, the two brands were interchanged as needed. Good to full improvement was seen in 90% of patients both with both brands. Injection doses and treatment responses were consistent during the study with both drugs. No major side effects were reported, and relatively few minor adverse events were reported, with clear reduction from the titration period (6.1%), to the remainder of the study (3.9%).Botulinum toxin (BTX-A) is a satisfactory long-term treatment without need for dose increase over. Both Botox and Dysport were effective when used interchangeably.

The Five-Year Prospective Study of Quality of Life in Hemifacial Spasm Treated with Abo-Botulinum Toxin A.

This study aimed to determine the long-term quality of life (QoL) in hemifacial spasm (HFS) patients after treating with Abo-botulinum toxin A (Abo-BTX). The study assessed the disease-specific QoL (hemifacial spasm questionnaire 30 items; HFS 30), the involuntary movements (abnormal involuntary movement scale; AIMS), general health QoL (Medical Outcomes 36-Item Short Form Health Survey; SF-36), and Depression (the Center of Epidemiologic Studies-Depression questionnaire; CES-D). A total of 74 HFS patients were enrolled from 2012 to 2017. The disease-specific QoL; involuntary movements; and the general health domain of SF 36 were significantly improved after injections of Abo-BTX A in the first few years (p < 0.04), but significantly decreased at the fifth year of treatment without significant clinical resistance observed (p < 0.001). Only the general health domain of SF 36 showed persistent improvement over five years (p = 0.02). In summary, Abo-BTX A can improved quality of life in the first few years; however only the general health domain of SF-36 showed significant improvement over five years (p = 0.02). No clinical resistance was observed.

Review of the Current Medical and Surgical Treatment Options for Microstomia in Patients With Scleroderma.

BACKGROUND: Most patients with scleroderma suffer from microstomia, which can have debilitating consequences on their quality of life. Unfortunately, treatment options remain limited. No specific guidelines exist; hence, microstomia remains a challenge to treat in this patient population. OBJECTIVE: This review aims to evaluate the different medical and surgical treatment modalities currently available for microstomia in patients with scleroderma and make recommendations for future research. MATERIALS AND METHODS: A search of PubMed, Ovid MEDLINE, and Ovid Embase was conducted to identify articles discussing the treatment of microstomia in scleroderma. Twenty articles discussing surgical therapy and one article discussing medical therapy were reviewed. RESULTS: Mostly because of a scarcity of high-level evidence, no individual therapy has documented long-term efficacy. Some treatments demonstrate positive results and warrant further research. CONCLUSION: Given the variability of results, specific recommendations for the treatment of microstomia in patients with scleroderma are difficult to establish. A multifaceted approach that includes surgical and medical therapy is likely the best option to improve oral aperture in this patient population. Surgical treatments such as neurotoxins, autologous fat grafting, and ultraviolet A1 phototherapy may hold the most potential for improvement.

Botulinum Toxin Type A to Improve Facial Symmetry in Facial Palsy: A Practical Guideline and Clinical Experience.

Unilateral peripheral facial nerve palsy jeopardizes quality of life, rendering psychological consequences such as low self-esteem, social isolation, anxiety, and depression. Among therapeutical approaches, use of Botulinum toxin type A (BoNT-A) on the nonparalyzed side has shown promising results and improvement of quality of life. Nevertheless, the correct technique is paramount, since over-injection of the muscles can result in lack of function, leading to a "paralyzed" appearance, and even worse, functional incompetence, which may cause greater distress to patients. Therefore, the objective of this article is to provide a practical guideline for botulinum toxin use in facial palsy. To this aim, adequate patient assessment, BoNT-A choice, injection plan and dosage, and injection techniques are covered.

The Effect of Depressor Anguli Oris Muscle Block on Facial Symmetry in Synkinetic Facial Paralysis Patients and Its Role in Preoperative Assessment.

BACKGROUND: Depressor anguli oris muscle hypertonicity in synkinetic facial paralysis patients may have an overpowering antagonistic effect on facial symmetry. Depressor anguli oris muscle block is a crucial diagnostic test before any treatment planning. Presented is the largest patient cohort analysis to date on static and dynamic facial symmetry changes after depressor anguli oris muscle block. METHODS: Unilateral synkinetic patients with depressor anguli oris muscle hypertonicity were included. Resting symmetry and smile modiolus angle, excursion, and exposure of teeth were measured on both synkinetic and healthy hemifaces before and after depressor anguli oris muscle block using Emotrics and FaceGram photographic analyses. RESULTS: Thirty-six patients were included. Before depressor anguli oris block, resting modiolus height was elevated on the synkinetic side (p = 0.047). During open-mouth smile, reduced modiolus angle (p < 0.0001), modiolus excursion (p < 0.0001), and exposure of teeth (p < 0.0001) were observed on the synkinetic hemiface. After depressor anguli oris block, resting modiolus height became symmetric (p = 0.64). During open-mouth smile, modiolus angle and exposure of teeth significantly increased (both p < 0.0001); excursion did not improve on the synkinetic side (p = 0.13) but unexpectedly improved in open-mouth smile on the healthy side (p = 0.0068). CONCLUSIONS: Depressor anguli oris muscle block improved resting symmetry and modiolus angle and exposure of teeth during smile, demonstrating the inhibitory mimetic role of a hypertonic depressor anguli oris muscle in synkinesis. It is a critical diagnostic and communication tool in the assessment and treatment planning of depressor anguli oris muscle hypertonicity, suggesting the potential effects of future depressor anguli oris myectomy. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Aesthetic ONE21 Technique for Injecting IncobotulinumtoxinA into the Forehead: Initial Experience With 86 Patients.

BACKGROUND: Treatment of upper facial lines is a common aesthetic practice; however, there is limited information on systematic tailored approaches for the treatment of forehead wrinkles using botulinum toxin A. OBJECTIVE: To describe the safety and efficacy of the ONE21 technique using incobotulinumtoxinA (INCO) for the treatment of forehead wrinkles. METHODS: Single-center, retrospective study with 86 females presenting a baseline Merz Aesthetic Scale (MAS) score ≥2 for dynamic forehead lines who had been treated with INCO using the ONE21 technique. Assessment was performed by two independent blinded raters using MAS for forehead lines (dynamic and at rest), and eyebrow positioning, based on standardized pictures taken before (baseline) and 4 (±2) weeks after treatment injection. The primary outcome was the percentage of subjects with a MAS improvement ≥2 points for dynamic forehead lines at week 4 (±2). Secondary outcomes were MAS scores for resting forehead lines and for eyebrow positioning. RESULTS: The mean age was 46.2 years, and mean total dose of INCO, 20.3 U. Most (97.7%) subjects had a MAS improvement of ≥2 points for dynamic forehead lines at week 4 (±2); 100% improved ≥1 point. MAS scores for resting and dynamic lines, and eyebrow positioning were significantly improved (P<0.001). Eyebrow positioning MAS improved ≥1 point in 56.9% of subjects, and 39.5% maintained the original shape. CONCLUSION: INCO injection using the ONE21 technique is effective and safe in treating forehead wrinkles, providing a natural result, with a customized treatment and a predictable eyebrow shape. J Drugs Dermatol. 2021;20(1):31-37. doi:10.36849/JDD.5617.

Effective Locations for Injecting Botulinum Toxin into the Mentalis Muscle; Cadaveric and Ultrasonographic Study.

The mentalis muscle is now considered key structures when performing procedures for rejuvenating the lower face. The aim of this study was to determine the anatomical morphology and location of the mentalis muscle and thereby provide anatomical information for facilitating clinical procedures designed to rejuvenate the lower face. Forty-four adult hemifaces from five Thai cadavers and 21 Korean cadavers were dissected to identify the locations of the mentalis muscle. Sixty-six hemifaces from 33 healthy young Korean subjects were included in an ultrasonographic study. The depth of the mentalis muscle below the skin surface, the thickness of the mentalis muscle, and the distance from the bone to the mentalis muscle were measured at the two points that were 5 mm lateral to the most-prominent point of the chin. The mentalis muscle was classified into two types based to its shape: in type A (86.4%, 38 of the 44 cases) it was dome shaped in three dimensions, while in type B (13.6%, 6 of the 44 cases) it was flat. The mentalis muscle was present mostly at the area 5-10 mm from the midsagittal line and 20-30 mm from a horizontal line connecting the mouth corners. The mentalis muscle was present between depths of 6.7 to 10.7 mm below the skin. This new information about the location of the mentalis muscle may help when identifying the most effective and safe botulinum toxin injection points and depths during esthetic procedures for weakened facial rhytides on the lower face.

The Use of Botulinum Toxin for Treatment of Depression.

A series of clinical studies have shown that botulinum toxin can treat major depression. Subjects suffering from unipolar depression may experience a quick, strong, and sustained improvement in the symptoms of depression after a single glabellar treatment with botulinum toxin.Preliminary data suggest that botulinum toxin therapy may also be effective in the treatment of other mental disorders characterized by an excess of negative emotions, such as borderline personality disorder.The mood-lifting effect of botulinum toxin therapy is probably mediated by the interruption of a proprioceptive feedback loop from the facial musculature to the emotional brain.