Ocular-oral synkinesis caused by partial injury of the zygomatic and buccal branches of the facial nerve after mid-face trauma.

BACKGROUND: Facial nerve paralysis induced by acute traumatic facial nerve injuries limited to the zygomatic and buccal branches shows unique complications, such as strong co-contractions of the lower facial muscles around the lips during voluntary blinking (ocular-oral synkinesis). We investigated the characteristics of facial complications after facial nerve injury in the mid-face area and reported the treatment results. METHODS: A total of 21 patients with facial nerve injuries to the zygomatic and/or buccal branches were evaluated for the degree of facial synkinesis and mouth asymmetry. Patients with mild-to-moderate symptoms were treated using physical rehabilitation therapy combined with botulinum toxin (Botox) injection, and patients with severe or uncontrolled symptoms were treated using surgical therapy. RESULTS: Initial/final mean synkinesis scores and mouth asymmetry degrees were 2.17/1.75 and 0.85/0.66 in the physical therapy group and 3.11/0.78 and 2.41/-0.31 in the surgery group, respectively. Physical therapy with Botox injection alone did not show significant improvements in synkinetic symptoms of the patients with mild-to-moderate synkinesis (p > 0.05), whereas surgical therapy resulted in significant improvements in synkinesis and mouth asymmetry (p < 0.05). CONCLUSIONS: Surgical treatment is an effective adjustment procedure for the management of facial complications in patients with severe or uncontrolled synkinesis after facial nerve injury to the mid-face area.

Clinical application of physical therapy in facial paralysis treatment: A review.

This review aims to summarize recent studies regarding the specific modalities of physical therapy as a form of treatment for patients with facial paralysis, analyze the different components of physical therapy, and provide healthcare providers with guidance for their best practice in treating patients with facial paralysis. This paper will discuss the mechanism, indications, and impact factors for facial retraining, evaluate the standards for facial retraining, the creation of a treatment plan, and analyze the combined use of facial retraining with botulinum toxin injections and the application of facial retraining in post facial reanimation patients. Other modes of physical therapy, including electrical stimulation, dry needling, and acupuncture, will be addressed. Lastly, the application of new digital technology will be discussed.

Botulinum toxin treatment of the buccinator muscle facial synkinesis: A systematic review.

BACKGROUND: The purpose of this review is to provide an overview of the available literature assessing the treatment of botulinum toxin injections for the treatment of synkinesis of the buccinator muscle in patients with peripheral facial palsy (PFP). MATERIALS AND METHODS: A multi database search was performed, including the following databases: Pubmed, Medline, Embase, and the Cochrane Library. Each database was searched from its earliest date until 8 June 2023. The following outcome measures were extracted from the articles when available: subjective, somatic, and psychological effects on the patients and objective outcomes such as the House-Brackmann, Sunnybrook and Sydney scores. The methodological quality of the included studies was rated using the Newcastle-Ottawa scale for nonrandomised trials. RESULTS: The primary literature search generated 37 articles. After removing duplicates, 25 articles remained for abstract appraisal, of which 20 underwent full-text appraisal, resulting in 3 studies for analysis. All of these studies showed (significant) improvement in synkinesis either measured using the Synkinesis Assessment Questionnaire or subjectively measured by asking treated patients. CONCLUSION: The available literature supports the finding that botulinum toxin treatment of the buccinator muscle could be a welcome addition to facial synkinesis treatment and could significantly improve patient outcomes. In future studies, the efficacy of EMG-guided buccinator injections, optimal dose, and a validated measuring method could be beneficial in optimising treatment for patients with a PFP and synkinesis.

Chemodenervation Algorithm: Functional and Aesthetic Considerations for Facial Harmony in Patients with Post-Facial Paralysis Synkinesis.

Management of post-facial paralysis synkinesis has evolved for the past decade with diversification of neuromuscular retraining, chemodenervation, and advanced surgical reanimation techniques. Chemodenervation with botulinum toxin-A is a commonly used treatment modality for synkinesis patients. Treatment has shifted from solely weakening the unaffected contralateral facial musculature for rote symmetry to selective reduction of undesired or overactive synkinetic muscles, allowing for a more organized motion of the recovered musculature. Facial neuromuscular retraining should be considered a crucial component of treating patients with synkinesis along with soft tissue mobilization, but specifics of these are beyond the scope of this article. Our goal was to create a descriptive platform for our method of chemodenervation treatment in the evolving field of post-facial paralysis synkinesis. A multi-institutional and multidisciplinary comparison of techniques was performed with photograph and video creation, review, and discussion over an electronic platform with all authors. Anatomic specifics of each region of the face and individual muscles were considered. A muscle by muscle algorithm for synkinesis therapy was created to include chemodenervation with botulinum toxin that should be considered for patients suffering from post-facial paralysis synkinesis.

Commentary on: "Chemodenervation Algorithm: Functional and Aesthetic Considerations for Facial Harmony in Patients with Post-Facial Paralysis Synkinesis," by Hetzler et al.

In this commentary, we discuss Hetzler et al.'s article, "Chemodenervation Algorithm: Functional and Aesthetic Considerations for Facial Harmony in Patients with Post-Facial Paralysis Synkinesis." The authors do an excellent job of presenting a guide for practitioners to use when initiating chemodenervation treatment for patients with nonflaccid facial paralysis. Standardization of outcome assessment tools and rigorous data collection will further refine treatment algorithms.

Botulinum Toxin in Facial Reanimation: Map of the Facial Musculature and Dosage.

Recovery from flaccid facial paralysis can lead to the development of postfacial paralysis synkinesis. Chemodenervation, or treatment with botulinum toxin (BT), is a common treatment for individuals with synkinesis. Patients should be assessed in a multidisciplinary setting to create a specific, individualized, and targeted chemodenervation regimen. This article highlights relevant facial musculature, anatomy, suggested injection patterns, and BT dosages for treating synkinesis patients. These patients require postinjection follow-up, and they should be evaluated by a specially trained facial physical therapist for facial retraining.

Botulinum toxin A treatment in facial palsy synkinesis: a systematic review and meta-analysis.

BACKGROUND: Synkinesis is defined as involuntary movements accompanying by voluntary movements and can occur during the aftermath of peripheral facial palsy, causing functional, aesthetic and psychological problems in the patient. Botulinum toxin A (BTX-A) is frequently used as a safe and effective treatment; however, there is no standardized guideline for the use of BTX-A in synkinesis. The purpose of this article is to review and summarize studies about the BTX-A treatment of synkinesis in patients with a history of peripheral facial palsy; including given dosages, injection sites and time intervals between injections. MATERIALS AND METHODS: A multi-database systematic literature search was performed in October 2020 using the following databases: Pubmed, Embase, Medline, and The Cochrane Library. Two authors rated the methodological quality of the included studies independently using the 'Newcastle-Ottawa Quality Assessment Scale' for non-randomised studies' (NOS). RESULTS: Four-thousand-five-hundred-and-nineteen articles were found of which 34 studies met the inclusion criteria, in total comprising 1314 patients. Most studies were assessed to be of 'fair' to 'good' methodological quality. The Cohen's kappa (between author FJ and AS) was 0.78. Thirty-one studies investigated the reported dosage injected, 17 studies reported injection location and 17 studies investigated time intervals. A meta-analysis was performed for three studies comprising 106 patients, on the effects of BTX-A treatment on the Synkinesis Assessment Questionnaire (SAQ) scores. The mean difference was 11.599 (range 9.422-13.766), p < 0.01. However, due to inconsistent reporting of data of the included studies, no relationship with the dosage and location could be assessed. CONCLUSIONS: Many treatment strategies for synkinesis exist, consisting of varying BTX-A brands, dosages, time intervals and different injection locations. Moreover, the individual complaints are very specific, which complicates creating a standardized chemodenervation treatment protocol. The BTX-A treatment of long-term synkinesis is very individual and further studies should focus on a patient-tailored treatment instead of trying to standardize treatment.

Surgical Treatment for Postparalytic Facial Synkinesis: A 35-Year Experience.

BACKGROUND: Surgical intervention with combined myectomy and neurectomy followed by functioning free muscle transplantation has been proposed to effectively resolve the problem of postparalytic facial synkinesis since 1985, and it continues to be the authors' standard of care. The authors aim to provide evidence that this surgical strategy is effective for treatment of synkinesis and smile quality. METHODS: One hundred three patients with postparalytic facial synkinesis were investigated (1985 to 2020). They all underwent extensive removal of the synkinetic muscles and triggered facial nerve branches in the cheek, nose, and neck regions, followed by gracilis functioning free muscle transplantation for facial reanimation. Ninety-four patients (50 with type II and 44 with type III postparalytic facial synkinesis), all of whom had at least 1 year of postoperative follow-up, were included in the study. Patient demographics and functional and aesthetic evaluations before and after surgery were collected. RESULTS: In the yearly distribution of the facial paralysis reconstruction, the incidence of surgical intervention increased from 15 percent before 2012 up to 24 percent in the years after. Young adults (79 percent) and female patients (63 percent) were the dominant population. Results showed a significant improvement of the facial smile quality, with more teeth visible while smiling, and a long-lasting decrease of facial synkinesis. Ninety-six percent of patients did not require botulinum toxin type A injection after surgery. Revision surgery for secondary deformity was 53 percent. CONCLUSIONS: Combined myectomy and neurectomy followed by functioning free muscle transplantation for type II and III synkinetic patients leads to promising and long-lasting results despite high revision rates. Refined techniques to decrease the revision rates are needed in the future. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Anatomic Considerations of Perinasal Musculature for Improved Dental Show During Smile in Facial Synkinesis.

Introduction: There is an anatomic explanation for upper lip and midfacial tethering resulting in lack of motion in facial synkinesis. Objective: To measure the effect of perinasal chemodenervation on dental show in the synkinetic population and clarify the anatomic relationship of perinasal musculature. Methods: Literature search was performed on anatomy of the perinasal modiolus, and anatomic evaluation was performed through human anatomic specimen dissection. Photographic outcomes were observed in synkinetic patients receiving chemodenervation to smile antagonists with and without perinasal muscle injections and assessed through naive observer survey. Retrospective outcomes for all patients receiving perinasal chemodenervation was collected utilizing Facial Clinimetric Evaluation Scale, Sunnybrook Facial Grading System (FGS), Facial Disability Index (FDI), and the Synkinesis Assessment Questionnaire. Results: Anatomic dissections demonstrated muscular confluence spanning the nasal sidewall and upper lip tethering the soft tissue to bone. Thirty-four of 53 chemodenervation patients received perinasal Botox experiencing improvement in synkinetic symptoms of the upper lip, nose, and improved dental show as noted on paired t-test for FGS (p = 0.00096), and FDI social p = 0.015) also supported by naive observer surveys (p = 0.03). Conclusions: Human anatomic specimen dissections support a perinasal confluence of musculature with bony attachments that can be successfully treated with chemodenervation in facial synkinesis patients.

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.

Long-term therapy with botulinum toxin in facial synkinesis: Retrospective data analysis of data from 1998 to 2018.

OBJECTIVES: Treatment with botulinum toxin A (BoNT) is the therapy of choice for many patients with facial synkinesis. Repeated injections relieve hypertonicity and hyperkinesis of reinnervated mimic muscles. Aim of the study was to prove if the injection regime and dosage of BoNT change during long-time therapy. DESIGN: Retrospective analysis of patients´ data, who were treated for synkinesis with BoNT from 1998 to 2018. SETTING: Tertiary referral facial nerve centre. PARTICIPANTS: Injection pattern of BoNT was based on clinical symptoms, observations of the specialist and on previous treatment pattern. Onabotulinumtoxin (OnaBoNT), Incobotulinumtoxin (IncoBoNT) and Abobotulinumtoxin (AboBoNT) were available for treatment. Patients consulted our department for following treatment as soon as the symptoms re-occurred. MAIN OUTCOME MEASURES: Change in dosage and injection pattern, the time intervals between treatments over the entire therapy period. RESULTS: Seventy-three patients were repeatedly injected. The median number of treatments was 18, the median treatment interval was 3.0 months. During the initial treatment, orbicularis oculi and the mentalis muscles were the most frequently injected muscles (94%). During repeated treatment, the number of injected muscles increased significantly (P < .0001), whereas the dose per muscle remained stable. The initial dose was 24 U (95%-CI 22-27 U) for OnaBoNT and IncoBoNT; 69 U for AboBoNT(95%-CI 44-94 U). We observed a significant increase in dosage for OnaBoNT and IncoBoNT (P < .0001) during the long-term therapy. The time intervals between treatments were stable for all three BoNT preparations (P > .05). CONCLUSIONS: We observed significant change in treatment dose and injection pattern of BoNT in patients with facial synkinesis. These results provide an orientation in dose finding and injection regimen of BoNT in the long-term course of therapy.

Buccinator synkinesis treated by botulinum toxin in facial palsy and hemifacial spasms.

OBJECTIVE: To assess botulinum toxin treatment for buccinator muscle synkinesis including: how often the synkinesis was troublesome; who benefitted and how from the treatment; and what were the adverse effects, ideal dosage, and injection site. SUBJECTS AND METHODS: Facial palsy (FP) patients and patients with hemifacial spasms who were attending for multiple site botulinum-toxin treatment for facial sequelae were assessed for buccinator synkinesis. The study group comprises those experiencing buccinator synkinesis with associated bothering symptoms who were willing to try injection also to the buccinator muscle. RESULTS: During 9/2017-12/2019, 126 different patients with facial sequelae were treated with multiple-site botulin-toxin injections by the author. Of them, 83 (66%) received injection also for buccinator synkinesis and 66/82 (80%) wanted to continue with the buccinator injections. The most remarkable results were seen with FP patients biting the mucus membrane of their cheek: usually the biting ceased totally. Patients with powerful hemifacial cheek spasms also experienced cessation of the spasms, contrasting any previous treatments. Adverse effects were mostly mild: slight weakness of the corner of the mouth or additional leakage of saliva or liquids. Only a few patients experienced more pronounced adverse effects. The most posterior contracting part of the buccinator muscle proved to be the best site for the injection. CONCLUSIONS: Buccinator synkinesis was very common and its treatment gave many patients additional relief from facial sequelae symptoms. Professionals treating patients with synkinesis and hemifacial spasms should add well-tolerated buccinator injections to their repertoire of injection sites.

Can the Jankovic-assessment be used as an alternative to electromyography? A cross-sectional study on facial dystonia patients treated with Botulinum toxin.

PURPOSE: This study aims to quantitatively compare the Jankovic assessment (JA) with electromyography (EMG)-based measures for assessing changes in facial movements in patients with facial dystonia. MATERIALS AND METHODS: Thirteen patients (five males and eight females) affected with different forms of facial dystonia (hemifacial spasm and synkinesis) participated in this study. All patients were treated with Botulinum Toxin (BTX) and evaluated with the JA scale and EMG-based measures, including motor unit potentials (MUP) latency and presence of polyphasic potentials before and after BTX injection. Correlation between the JA scores and the EMG-based measures was calculated. Statistical analysis was performed with the Pearson test. RESULTS: Correlation between the JA scores and the EMG-based measures was found to be statistically significant, both before and after treatment with BTX. CONCLUSION AND RELEVANCE: JA scores significantly correlated with more objective EMG-based measures, suggesting that the JA scale can be used to assess facial movement changes, for example elicited by a treatment such as BTX injection. Thus, in facial dystonia patients, the JA scale may be used for evaluating treatment outcomes as a valid and low-cost alternative to EMG.

Comparison of Myelin-Associated Glycoprotein With Vincristine for Facial Nerve Inhibition After Bilateral Axotomy in a Transgenic Thy1-Gfp Rat Model.

IMPORTANCE: Aberrant synkinetic movement after facial nerve injury can lead to prominent facial asymmetry and resultant psychological distress. The current practices of neuroinhibition to promote greater facial symmetry are often temporary in nature and require repeated procedures. OBJECTIVE: To determine whether myelin-associated glycoprotein (MAG), a specific neuroinhibitor, can prevent neuroregeneration with efficacy comparable with that of vincristine, a well-established neurotoxin. DESIGN, SETTING, AND PARTICIPANTS: Rats transgenic for Thy-1 cell surface antigen-green fluorescent protein (Thy1-Gfp) were randomized into 3 groups. Each rat received bilateral crush axotomy injuries to the buccal and marginal mandibular branches of the facial nerves. The animals received intraneural injection of saline, MAG, or vincristine. MAIN OUTCOMES AND MEASURES: The animals were imaged via fluorescent microscopy at weeks 1, 3, 4, and 5 after surgery. Quantitative fluorescent data were generated as mean intensities of nerve segments proximal and distal to the axotomy site. Electrophysiological analysis, via measurement of compound muscle action potentials, was performed at weeks 0, 3, 4, and 5 after surgery. RESULTS: A total of 12 rats were included in the study. Administration of MAG significantly reduced fluorescent intensity of the distal nerve in comparison with the control group at week 3 (mean [SD], MAG group: 94 [11] intensity units vs control group: 130 [11] intensity units; P < .001), week 4 (MAG group: 81 [19] intensity units vs control group: 103 [9] intensity units; P = .004), and week 5 (MAG group: 76 [10] intensity units vs control group: 94 [10] intensity units; P < .001). In addition, rats treated with MAG had greater fluorescent intensity than those treated with vincristine at week 3 (mean [SD], MAG group: 94 [11] intensity units vs vincristine group: 76 [6] intensity units; P = .03), although there was no significant difference for weeks 4 and 5. At week 5, both MAG and vincristine demonstrated lower distal nerve to proximal nerve intensity ratios than the control group (control group, 0.94; vs MAG group, 0.82; P = .01; vs vincristine group; 0.77; P < .001). There was no significant difference in amplitude between the experimental groups at week 5 of electrophysiological testing. CONCLUSIONS AND RELEVANCE: Lower facial asymmetry and synkinesis are common persistent concerns to patients after facial nerve injury. Using the Thy1-Gfp rat, this study demonstrates effective inhibition of neuroregeneration via intraneural application of MAG in a crush axotomy model, comparable with results with vincristine. By potentially avoiding systemic toxic effects of vincristine, MAG demonstrates potential as an inhibitor of neural regeneration for patients with synkinesis. LEVEL OF EVIDENCE: NA.

Treatment Patterns and Outcomes in Botulinum Therapy for Patients With Facial Synkinesis.

IMPORTANCE: In the last decade, there has been a significant increase in the number of practitioners administering botulinum toxin for facial synkinesis. However, there are few resources available to guide treatment patterns, and little is known about how these patterns are associated with functional outcomes and quality of life. OBJECTIVE: To evaluate botulinum treatment patterns, including the dosing and frequency of muscle targeting, for treatment of facial synkinesis and to quantify patient outcomes. DESIGN, SETTING, AND PARTICIPANTS: This prospective cohort study of 99 patients treated for facial synkinesis was conducted from January 2016 through December 2018 at the Vanderbilt Bill Wilkerson Center in Nashville, Tennessee, a tertiary referral center. INTERVENTION: Onabotulinum toxin A treatment of facial synkinesis. MAIN OUTCOMES AND MEASURES: Patient-reported outcomes on the Synkinesis Assessment Questionnaire and botulinum treatment patterns, including the dosages and frequency of injection for each facial muscle, were compared at the initiation of treatment and at the end of recorded treatment. RESULTS: In total, 99 patients (80 female patients [81%]) underwent botulinum injections for treatment of facial synkinesis. The median (interquartile range) age was 54.0 (43.5-61.5) years, and the median (interquartile range) follow-up was 27.1 (8.9-59.7) months. Most patients underwent injections after receiving a diagnosis of Bell palsy (41 patients, 41%) or after resection of vestibular schwannoma (36 patients [36%]). The patients received a total of 441 treatment injections, and 369 pretreatment and posttreatment Synkinesis Assessment Questionnaire scores were analyzed. The mean botulinum dose was 2 to 3 U for each facial muscle and 9 to 10 U for the platysma muscle. The dose increased over time for the majority of all muscles, with steady state achieved after a median of 3 treatments (interquartile range, 2-3). Linear regression analysis for cluster data of the mean total questionnaire score difference was -14.2 (95% CI, -17.0 to -11.5; P < .001). There was a significant association of postinjection questionnaire score with younger patients, female sex, total dose, and synkinesis severity. Oculo-oral synkinesis may respond more to treatment compared with oro-ocular synkinesis. CONCLUSION AND RELEVANCE: Patients with facial synkinesis responded significantly to botulinum treatment. Treatment began with 6 core facial muscles that were injected during most treatment sessions, and dosages increased after the first injection until steady state was achieved. Those with a greater degree of morbidity, younger patients, and females showed significant improvement, and the larger the dose administered, the greater the response. Oculo-oral synkinesis may be more responsive than oro-ocular synkinesis. LEVEL OF EVIDENCE: 3.

Synkinesis Between Orbicularis Oculi and Procerus Muscles: Video Presentation of an Unusual Type of Aberrant Innervation after Cosmetic Rhinoplasty.

BACKGROUND: Synkinesis is a recognized complication following peripheral facial nerve paralysis. Different types of synkinesis have been described, with oral-ocular and ocular-oral synkinesis being the most common. Ocular-nasal synkinesis has been reported in two patients following cosmetic rhinoplasty. However, synkinesis between the orbicularis oculi and procerus muscles has not been reported by now. METHODS: This is an interventional case report. RESULTS: Two women, aged 42 and 37 years, presented with unilateral contraction of the medial eyebrow muscles (procerus) with spontaneous or voluntary blinking, 4 and 5 months after cosmetic rhinoplasty, respectively. Both were successfully treated with injection of botulinum toxin A. CONCLUSIONS: Surgical trauma is inevitable during every procedure, including rhinoplasty, and may damage the fine structures including branches of the facial nerve innervating the muscles. Gentle tissue handling may minimize iatrogenic injury to the fine motor branches of the facial nerve and prevent subsequent aberrant innervation and synkinesis. Botulinum toxin A injection can effectively, yet temporarily, resolve the unintentional contractions and provide significant patient comfort. 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 .

Paradoxical Frontalis Activation: An Underrecognized Consequence of Facial Palsy.

BACKGROUND: Aberrant reinnervation and synkinesis are common and debilitating after facial palsy. Paradoxical frontalis activation can antagonize eye closure and increase the risk of corneal damage. If recognized, judicious botulinum toxin injection to the affected side may reduce this risk. METHODS: One hundred consecutive patients with synkinesis were identified from a prospective database. Routine facial view photographs were converted to a standardized scale using iris diameter. The vertical distance from the midpoint of the midcanthal line to the inferior border of the eyebrow was measured bilaterally. A value of p < 0.05 was considered significant. RESULTS: Eighty-two patients were included, with a median age of 44 years (interquartile range, 33 to 59 years); 59 of the patients were women. The commonest cause was idiopathic (n = 55). The median time since onset of palsy was 13 months (interquartile range, 6.5 to 27 months). There was less midpoint of the midcanthal line to the inferior border of the eyebrow excursion on the synkinetic side of the face (p < 0.001). Twenty-two patients (27 percent) displayed paradoxical frontalis movement on the affected side of their face, with increased midpoint of the midcanthal line to the inferior border of the eyebrow distance (eyebrow raise) when attempting eye closure compared with eyebrow raise (n = 19), and tight eye closure compared with gentle eye closure (n = 3). CONCLUSIONS: This study highlights the phenomenon of paradoxical frontalis activation during eye closure. This is often underrecognized and may contribute to lagophthalmos. The authors found it to be present in 27 percent of patients with moderate or severe synkinesis. Further dynamic studies are required to understand the relationship among frontalis activity, eye closure, and the effects of its inhibition.

Effect of 3 Commercially Available Botulinum Toxin Neuromodulators on Facial Synkinesis: A Randomized Clinical Trial.

IMPORTANCE: Botulinum toxin neuromodulators are an important treatment for facial synkinesis. Whether a difference in efficacy exists among the 3 different botulinum neuromodulators used in treating this condition remains unknown. OBJECTIVE: To evaluate the effectiveness of 3 commercially available botulinum toxin neuromodulators in the treatment of facial synkinesis. DESIGN, SETTING, AND PARTICIPANTS: In this single-blind, 3-arm comparison randomized clinical trial, 28 patients at the Facial Nerve Center, University of Utah, Salt Lake City, were randomized to onabotulinumtoxinA, abobotulinumtoxinA, or incobotulinumtoxinA treatment. Each patient was given the Synkinesis Assessment Questionnaire (SAQ) to assess severity of synkinesis before treatment and 1, 2, and 4 weeks after treatment, and improvements were compared among the groups. Data were collected from July 3, 2012, to March 31, 2015. INTERVENTIONS: Botulinum toxin type A neuromodulator (onabotulinumtoxinA, abobotulinumtoxinA, or incobotulinumtoxinA) injected into synkinetic areas of the face. MAIN OUTCOMES AND MEASURES: Synkinesis assessed using the SAQ (score range, 20-100; lower scores indicate less severe synkinesis) before treatment and 1, 2, and 4 weeks after treatment. RESULTS: A total of 28 patients (mean [SD] age, 49.1 [18.5] years; 8 [28.6%] male and 20 [71.4%] female), with 6 patients enrolled multiple times, received 38 treatments (15 onabotulinumtoxinA, 13 abobotulinumtoxinA, and 10 incobotulinumtoxinA). No significant difference existed in baseline pretreatment SAQ scores among the 3 groups. Mean (SD) SAQ score improvement at 4 weeks was 41% (31%) for the onabotulinumtoxinA, 42% (20%) for the abobotulinumtoxinA, and 17% (18%) for the incobotulinumtoxinA groups. No significant differences were noted in SAQ score improvements among the 3 groups at weeks 1 and 2 after treatment (week 1 mean improvements of 42% in the onabotulinumtoxinA, 45% in the abobotulinumtoxinA, and 26% in the incobotulinumtoxinA groups; P = .19; week 2 mean improvements of 43% in the onabotulinumtoxinA, 46% in the abobotulinumtoxinA, and 28% in the incobotulinumtoxinA groups; P = .20). The difference in mean SAQ score improvement for abobotulinumtoxinA vs incobotulinumtoxinA from pretreatment to 4 weeks after treatment was not significant (30 vs 12 points; P = .11) despite a significant difference in mean total SAQ score for abobotulinumtoxinA vs incobotulinumtoxinA (40.34 vs 58.00; P = .02). CONCLUSIONS AND RELEVANCE: AbobotulinumtoxinA had similar efficacy to onabotulinumtoxinA and incobotulinumtoxinA for the management of facial synkinesis up to 4 weeks after treatment. IncobotulinumtoxinA had significantly less effect on SAQ score improvement than onabotulinumtoxinA at 4 weeks, perhaps because of the shorter duration of action. Shorter intervals between treatments or larger doses may be required when using incobotulinumtoxinA treatment for facial synkinesis. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT03048383. LEVEL OF EVIDENCE: 1.