Does supercharging with cross-face nerve graft enhance smile in non-flaccid facial paralysis patients undergoing selective neurectomy?

BACKGROUND: Cross face nerve grafting (CFNG) is a well-established nerve transfer technique in facial reanimation; however, no study has assessed outcome of supercharging the smile with CFNG in patients with synkinesis. The goal of this study was to examine the smile outcome in non-flaccid facial paralysis (NFFP) patients after supercharging with CFNG during selective neurectomy. METHODS: NFFP patients who underwent CFNG with end-to-side coaptation to a smile branch on the paralyzed side during selective neurectomy were retrospectively identified and their charts were reviewed. Pre-operative and post-operative facial function was assessed with the electronic clinician-graded facial function tool (eFACE), and an automated computer-aided facial assessment tool (Emotrics). Smile metrics were compared pre-operatively, in early post-operative time (EPO, <6 months), and late post-operative time (LPO, >9 months) when CFNG contribution would be expected. RESULTS: Thirteen cases were performed between June 2019 and December 2021. No objective smile metrics improved following supercharging with CFNG. Oral commissure excursion improved by 1.23 points in eFACE (p = .812), and by 0.84 in Emotrtics (p = .187) from EPO to LPO. EFACE dynamic score was improved by 0.08 points from EPO to LPO (p = .969). CONCLUSIONS: Using CFNG for supercharging the smile during selective neurectomy in NFFP patients may not enhance smile. Longer term results following supercharging and long term natural history of selective neurectomy should be assessed.

Nasolabial fold dynamics: Implications for facial paralysis and facial reanimation surgery.

OBJECTIVES: In patients with facial paralysis, facial reanimation surgery may be needed to normalize facial soft tissue function/movements. Critical for this normalization is the dynamics of the nasolabial folds (NLFs). The objective of this prospective, observational study was to determine the 3D morphologic dynamics of the NLFs in patients with unilateral facial palsy and normal subjects. SETTINGS AND SAMPLE POPULATION: 3D facial soft tissue movement data collected from adults with unilateral, facial paralysis (Bell's Palsy, n = 36); and (2) an age- and sex-frequency matched control group (n = 68). MATERIALS AND METHODS: Movement data were collected during repeated animations from participants using a video-based motion capture system. Movement in terms of displacement and asymmetry of the NLFs, nasal and circumoral regions were analyzed in the lateral, vertical and depth planes; as well as movement of the commissure and NLFs relative to the lower lip midline. Two-sample t tests were used to test for significant group differences. RESULTS: Patients NLFs had less mean displacement, greater mean asymmetry and uncoordinated movements compared with the controls. For both groups during smiling, the NLF and commissure landmarks had approximately similar magnitudes of displacement (control range = 11-14mm; patient range = 7-10mm). CONCLUSION: NLF dynamics during smiling were as significant as oral commissure excursion. Thus, an immobile NLF is an unnatural feature of facial animations. Surgical treatments that address impaired NFL movements must be considered to create a more natural surgical outcome especially during smiling.

Facial mobility and recovery in patients with unilateral facial paralysis.

OBJECTIVE: (a) To quantify longitudinal 3D changes in facial soft tissue movements in adults with unilateral facial paralysis, and (b) to compare the patients' movements with an age- and sex-frequency matched control group. SETTINGS AND SAMPLE POPULATION: Prospective 3D facial movement data of 36 patients and 68 control participants. Patients' data were collected within 6 weeks of onset of symptoms (baseline) and then at 3 and 12 weeks after baseline. MATERIALS AND METHODS: The 3D facial movement data were collected during different facial animations. Mean group measurements of displacement, velocity and asymmetry were computed. Two sample t tests were used to test for significant group differences, and linear mixed models were fit to test for significant changes over time in the patient group. Also, 3D dynamic modelling and vector plots were computed to isolate the patients' abnormal movements and/or paralysis. RESULTS: The patients' mean baseline movements were significantly less for both the paralysed and contralateral sides of the face with much greater movement asymmetry than the controls. Patients' mean measures improved significantly from baseline to 12 weeks. The measures were closer to, but fell short of, the control values. CONCLUSION: In unilateral facial paralysis, the contralateral facial side was affected by the paralysis and may be tethered or limited in its movement by the paralysed side. The comprehensive measurement set and 3D facial mapping effectively tracked patient recovery and isolated paralysed facial regions. The 3D measures can be used for diagnosis and outcome assessment of different treatments.

Long-Term Outcomes of Free Gracilis Muscle Transfer for Smile Reanimation in Children.

OBJECTIVE: To evaluate long-term outcomes of free gracilis muscle transfer (FGMT) for smile reanimation on smile excursion, facial symmetry, and quality of life in a cohort of children with facial palsy. STUDY DESIGN: A retrospective analysis of 40 pediatric patients who underwent FGMT for facial palsy at the Massachusetts Eye and Ear Infirmary Facial Nerve Center was performed. Preoperative and postoperative photography and videography were used to quantify smile excursion and facial symmetry. Preoperative and postoperative quality of life was assessed with the Facial Clinimetric Evaluation (FaCE) survey, a validated, patient-based instrument for evaluating facial impairment and disability. RESULTS: Of the 40 patients who underwent FGMT for facial palsy, 38 patients had complete data including preoperative and postoperative photography and videography from 3 months to 10 years following surgery; 13 cases had >5 years of follow-up. FGMT resulted in significant improvements in smile excursion within several months, with continued improvements in smile excursion and symmetry demonstrated more than 5 years later. Fifteen patients completed preoperative and postoperative FaCE surveys, which demonstrated significant improvement in quality of life scores following FGMT. CONCLUSIONS: FGMT significantly improves smile, facial asymmetry, and quality of life for years after this surgery for facial palsy.

Surgical Refinement Following Free Gracilis Transfer for Smile Reanimation.

IMPORTANCE: Gracilis free muscle transfer is widely regarded as the gold standard functional smile reanimation in long-standing facial palsy. Although most patients achieve meaningful oral commissure movement, a subset has suboptimal aesthetic outcomes due to midfacial bulk or oral commissure malposition. Safe refinements that do not compromise excursion would be a welcome addition to the surgical armamentarium for this population. OBJECTIVES: The goal of this study was to describe surgical approaches to the 3 most common postoperative sequelae that detract from the final result after gracilis facial reanimation and to examine how these surgical refinements affect aesthetic outcome, smile excursion, and quality of life. DESIGN: This was a retrospective case series. SETTING: Tertiary care center (Massachusetts Eye and Ear Infirmary Facial Nerve Center). PARTICIPANTS: Of 260 gracilis transfers performed since 2003, meaningful excursion (>3 mm) but poor aesthetic outcome requiring additional surgery was noted in 21 patients and was related either to excess muscle bulk (9), resting inferior malposition of the oral commissure (9), or resting superior/lateral malposition of the oral commissure (3). INTERVENTION: Specific surgical interventions to address each of these negative sequelae were developed and refined, to preserve muscle functionality but eliminate the unsightly feature. MAIN OUTCOME: Aesthetic status, determined by midfacial symmetry; quantitative smile excursion; and quality of life (using the FaCE instrument) were measured before and after revision. RESULTS: Patients who underwent gracilis refinement directed at either muscle debulking, or gracilis tightening or loosening experienced significantly improved aesthetics/midfacial symmetry and improved quality of life with no significant decrease in smile excursion. CONCLUSIONS: Improved aesthetics and quality of life can be achieved through targeted revision of the gracilis free tissue transfer, without significant loss of smile excursion.

The Dilator Naris Muscle as a Reporter of Facial Nerve Regeneration in a Rat Model.

OBJECTIVE: Many investigators study facial nerve regeneration using the rat whisker pad model, although widely standardized outcomes measures of facial nerve regeneration in the rodent have not yet been developed. The intrinsic whisker pad "sling" muscles producing whisker protraction, situated at the base of each individual whisker, are extremely small and difficult to study en bloc. Here, we compare the functional innervation of 2 potential reporter muscles for whisker pad innervation: the dilator naris (DN) and the levator labii superioris (LLS), to characterize facial nerve regeneration. METHODS: Motor supply of the DN and LLS was elucidated by measuring contraction force and compound muscle action potentials during stimulation of individual facial nerve branches, and by measuring whisking amplitude before and after DN distal tendon release. RESULTS: The pattern of DN innervation matched that of the intrinsic whisker pad musculature (ie, via the buccal and marginal mandibular branches of the facial nerve), whereas the LLS seemed to be innervated almost entirely by the zygomatic branch, whose primary target is the orbicularis oculi muscle. CONCLUSIONS: Although the LLS has been commonly used as a reporter muscle of whisker pad innervation, the present data show that its innervation pattern does not overlap substantially with the muscles producing whisker protraction. The DN muscle may serve as a more appropriate reporter for whisker pad innervation because it is innervated by the same facial nerve branches as the intrinsic whisker pad musculature, making structure/function correlations more accurate, and more relevant to investigators studying facial nerve regeneration.

Bell's palsy: aetiology, clinical features and multidisciplinary care.

Bell's palsy is a common cranial neuropathy causing acute unilateral lower motor neuron facial paralysis. Immune, infective and ischaemic mechanisms are all potential contributors to the development of Bell's palsy, but the precise cause remains unclear. Advancements in the understanding of intra-axonal signal molecules and the molecular mechanisms underpinning Wallerian degeneration may further delineate its pathogenesis along with in vitro studies of virus-axon interactions. Recently published guidelines for the acute treatment of Bell's palsy advocate for steroid monotherapy, although controversy exists over whether combined corticosteroids and antivirals may possibly have a beneficial role in select cases of severe Bell's palsy. For those with longstanding sequaelae from incomplete recovery, aesthetic, functional (nasal patency, eye closure, speech and swallowing) and psychological considerations need to be addressed by the treating team. Increasingly, multidisciplinary collaboration between interested clinicians from a wide variety of subspecialties has proven effective. A patient centred approach utilising physiotherapy, targeted botulinum toxin injection and selective surgical intervention has reduced the burden of long-term disability in facial palsy.

Contemporary management of Bell palsy.

Bell palsy (BP) is the most common diagnosis in acute and chronic facial palsy. Although most patients fully recover, more than one-quarter will have residual dysfunction. Of these, nearly half will demonstrate severe limitations in facial expression. Though significant attention has been paid to acute management and prognosis, a paucity of literature exists addressing management of the long-term sequelae of BP. This article describes contemporary use of physical therapy, injectables, and static and dynamic surgical procedures in facial reanimation of acute and chronic BP.

Long-term functional recovery after facial nerve transection and repair in the rat.

BACKGROUND: The rodent model is commonly used to study facial nerve injury. Because of the exceptional regenerative capacity of the rodent facial nerve, it is essential to consider the timing when studying facial nerve regeneration and functional recovery. Short-term functional recovery data following transection and repair of the facial nerve has been documented by our laboratory. However, because of the limitations of the head fixation device, there is a lack of long-term data following facial nerve injury. The objective of this study was to elucidate the long-term time course and functional deficit following facial nerve transection and repair in a rodent model. METHODS: Adult rats were divided into group 1 (controls) and group 2 (experimental). Group 1 animals underwent head fixation, followed by a facial nerve injury, and functional testing was performed from day 7 to day 70. Group 2 animals underwent facial nerve injury, followed by delayed head fixation, and then underwent functional testing from months 6 to 8. RESULTS: There was no statistical difference between the average whisking amplitudes in group 1 and group 2 animals. CONCLUSION: Functional whisking recovery 6 months after facial nerve injury is comparable to recovery within 1 to 4 months of transection and repair, thus the ideal window for evaluating facial nerve recovery falls within the 4 months after injury.

The success of free gracilis muscle transfer to restore smile in patients with nonflaccid facial paralysis.

BACKGROUND: Development of synkinesis, hypertonicity, and poor smile excursion after facial nerve insult and recovery contribute to disfigurement, psychological difficulties, and an inability to convey emotion via facial expression. Despite treatment with physical therapy and chemodenervation, some patients who recover from transient flaccid facial paralysis never spontaneously regain the ability to perform a meaningful smile. METHODS: Prospective evaluation was performed on 20 patients with nonflaccid facial paralysis who underwent free gracilis muscle transfer. Patients were evaluated using the quality-of-life (QOL) FaCE survey, Facial Nerve Grading Scale, and Facegram to quantify QOL improvement, smile excursion, and symmetry after muscle transfer. RESULTS: A statistically significant increase in the FaCE score was seen after muscle transfer (paired 2-tailed t test, P < 0.039). In addition, there was a statistically significant improvement in the smile score on the Facial Nerve Grading Scale (P < 0.002), in the lower lip length at rest (P = 0.01) and with smile (P = 0.0001), and with smile symmetry (P = 0.0077) after surgery. CONCLUSIONS: Free gracilis muscle transfer has become a mainstay in the management armamentarium for patients who develop severe reduction in oral commissure movement after facial nerve insult and recovery. The operation achieves a high overall success rate, and innovations involving transplanting thinner segments of muscle avoid a cosmetic deformity secondary to excess bulk. This study demonstrates a quantitative improvement in QOL and facial function after free gracilis muscle transfer in patients who failed to achieve a meaningful smile after physical therapy.

Contemporary facial reanimation.

The facial nerve is the most commonly paralyzed nerve in the human body. Facial paralysis affects aesthetic appearance, and it has a profound effect on function and quality of life. Management of patients with facial paralysis requires a multidisciplinary approach, including otolaryngologists, plastic surgeons, ophthalmologists, and physical therapists. Regardless of etiology, patients with facial paralysis should be evaluated systematically, with initial efforts focused upon establishing proper diagnosis. Management should proceed with attention to facial zones, including the brow and periocular region, the midface and oral commissure, the lower lip and chin, and the neck. To effectively compare contemporary facial reanimation strategies, it is essential to employ objective intake assessment methods, and standard reassessment schemas during the entire management period.

"Muscle foreshortening after free gracilis transfer for smile: Where, when, why?"

BACKGROUND: Gracilis free muscle transfer (GFMT) remains the standard for smile restoration in patients with long-standing facial palsy. Resting oral commissure lateralization (ROCL) following GFMT is aesthetically unappealing and can cause functional problems including dysarthria and oral incompetence. The risk factors for ROCL following GFMT are poorly understood. METHODS: Of all patients who underwent GFMT for smile restoration from 2003 - 2021, patients with subsequent ROCL were identified from a facial nerve database using pre-determined search criteria. Medical records were reviewed to identify potential risk factors for muscle foreshortening. RESULTS: Of 412 patients who underwent successful GFMT since 2003, we identified 41 (10%) patients who subsequently developed ROCL. ROCL rates varied significantly based on gracilis innervation source, with ipsilateral CN VII innervation and dual-innervation (cross-facial nerve graft (CFNG) plus ipsilateral nerve-to-masseter (NTM)) demonstrating the highest foreshortening rates (27.3% and 15.4%, respectively), compared to the lowest rates of foreshortening when gracilis was innervated by CNFG alone (3.2%), p=0.005. Patients with a history of radiation to the surgical field were significantly more likely to develop ROCL (22%) compared to those without a history of radiation (8.6%), p<0.001. Furthermore, the rate of ROCL was significantly higher among patients who underwent concurrent stabilization of the nasolabial fold using a wide band of fascia lata (20.8%) compared to those who did not (6.6%), p<0.001. CONCLUSIONS: Herein we report potential risk factors for ROCL following GFMT for smile restoration, including innervation source, radiation history, and concurrent fascia lata static suspension.

Favorable Outcome Perception in Facial Selective Neurectomy.

OBJECTIVE: Facial selective neurectomy (SN) improves facial function by denervation of muscles antagonistic to the smile in nonflaccid facial paralysis (NFFP) patients. This study aims to assess whether and which objective facial function metrics affect favorable SN outcome in NFFP patients, as perceived by facial nerve (FN) practitioners. STUDY DESIGN: Retrospective cohort study. SETTING: NFFP patients who underwent SN at the facial nerve center. METHODS: Standardized preoperative and postoperative facial photographs of patients undergoing SN were analyzed using clinician-graded measures (eFACE) and automated facial measurement (Emotrics). Favorable outcome was ranked subjectively by 3 independent FN practitioners. Correlations between objective metrics and favorable subjective outcome were examined. RESULTS: Fifty-eight SN cases were included. Oral commissure excursion with smile, interlabial distance, and lower lip movement were all considered statistically significantly important for favorable outcome perception. Each +1 mm of smile excursion increases the odds of a favorable outcome by 75.4% (odds ratio [OR]: 1.754). Each +1 mm of interlabial distance asymmetry decreases the odds of a favorable outcome by 24.7% (OR: 0.753). Each +1-point change in lower lip movement eFACE score increases the odds of a favorable outcome by 2.7% (OR: 1.027). CONCLUSION: Several smile metrics contribute to favorable SN outcome perception among FN practitioners. Smile excursion, interlabial distance, and lower lip movement were significant predictors of success. These observations may be extrapolated to other facial reanimation interventions and serve surgeons and patients during counseling and expectation management, and during surgery.

Freeing the Animal Model: A Modular, Wirelessly Powered, Implantable Electronic Platform.

SUMMARY: Fully implantable electronic devices in freely roaming animal models are useful in biomedical research, but their development is prohibitively resource intensive for many laboratories. The advent of miniaturized microcontrollers with onboard wireless data exchange capabilities has enabled cost-efficient development of myriad do-it-yourself electronic devices that are easily customizable with open-source software ( https://www.arduino.cc/ ). Likewise, the global proliferation of mobile devices has led to the development of low-cost miniaturized wireless power technology. The authors present a low-cost, rechargeable, and fully implantable electronic device comprising a commercially available, open-source, wirelessly powered microcontroller that is readily customizable with myriad readily available miniature sensors and actuators. The authors demonstrate the utility of this platform for chronic nerve stimulation in the freely roaming rat with intermittent wireless charging over 4 weeks. Device assembly was achieved within 2 hours and necessitated only basic soldering equipment. Component costs totaled $115 per device. Wireless data transfer and wireless recharging of device batteries was achieved within 30 minutes, and no harmful heat generation occurred during charging or discharging cycles, as measured by external thermography and internal device temperature monitoring. Wireless communication enabled triggered cathodic pulse stimulation of the facial nerve at various user-selected programmed frequencies (1, 5, and 10 Hz) for periods of 4 weeks or longer. This implantable electronic platform could be further miniaturized and expanded to study a vast array of biomedical research questions in live animal models. CLINICAL RELEVANCE STATEMENT: The clinical relevance of electrical stimulation in neural recovery remains controversial, and long-term neural stimulation in small animal models is challenging. We have developed a low-cost, fully implantable, wirelessly powered nerve stimulation device to facilitate further research in nerve stimulation in animal models.

Pre-Operative Factors May Predict Outcome in Selective Neurectomy for Synkinesis.

Background: While there has been great interest in offering selective neurectomy (SN) to patients with nonflaccid facial palsy (NFFP), postoperative outcomes are inconsistent. Objective: To assess overall SN outcome in NFFP patients and to examine correlation between preoperative factors and SN outcome. Methods: SN cases were retrospectively identified between 2019 and 2021. Patient factors and facial function were assessed using chart review, the Facial Clinimetric Evaluation (FaCE), the electronic clinician-graded facial function tool (eFACE), and an automated computer-aided facial assessment tool (Emotrics). Correlations between preoperative factors and patients outcome were established. Results: Fifty-eight SN cases were performed; 88% were females, and median age was 53 years (range 11-81). Outcome assessment was 8 months on average (1-24 months). Postoperatively, multiple eFACE and Emotrics parameters improved significantly, including ocular, perioral, and synkinesis metrics. In preoperative factors assessment, age >50, facial palsy (FP) duration >2 years, poor preoperative facial function, and nontrauma etiology all correlated with greater improvements compared with younger patients, those with shorter duration facial palsy, trauma etiology, and better preoperative facial function. Conclusions: SN can significantly improve facial function; we have identified several preoperative factors that correlated to outcome.

Understanding the Relationship Between Facial Nerve Branch Sacrifice and Selective Neurectomy Outcome.

Introduction: While there is great interest in selective neurectomy (SN) for patients with synkinesis, outcomes can be inconsistent. Objective: To examine the relationships between intraoperative facial nerve branch transection and both postoperative outcome and functional deficits. Methods: SN cases, with minimal follow-up of 4 months, were retrospectively identified between 2019 and 2021; outcome was assessed using FaCE instrument, eFACE and Emotrics. Correlations between intraoperative facial nerve branch preservation or transection, and functional outcome and new functional deficits were examined. Results: Fifty-six cases were performed: 88% were females, and median age was 53 years (range 11-81). Mean follow-up was 19.5 months (range 4-42). Oral commissure excursion improved in patients where all smile branches were preserved, no vertical vector smile branches were transected, and more than three smile antagonist branches were transected. A linear trend between smile antagonist branch sacrifice and favorable smile outcome was found. Lower lip movement was improved in patients in whom more than half of the identified lower lip branches were transected. Thirty percent of patients experienced untoward postoperative functional deficits, from which 47% recovered with interventions. Conclusions: Several correlations between SN intra-operative decisions and outcome were identified; new or worsening functional deficit rate can be high. However, chemodenervation or fillers can help diminish these deficits.

A comparison of facial nerve grading systems.

PURPOSE: This study aimed to compare a computerized tool to standard objective clinical scales for global and zone-specific assessment of facial nerve function. METHODS: This was a retrospective review of 77 patients with facial paralysis who underwent facial videography. Videos were independently scored by 3 facial nerve specialists using the House-Brackmann Scales (HBI and HBII). Digital scoring was performed with Facogram software. Scores were recorded and compared using intraclass and Pearson (r) correlations. RESULTS: Interobserver correlation was high with HBII, with overall scores in excellent agreement (intraclass correlation range, 0.78-0.95; P ≤ 0.0001). There were strong correlations between Facogram and HBII (r ≥ 0.67, P ≤ 0.0001) and strong intraobserver correlations between HBI and HBII (r ≥ 0.71, P ≤ 0.0001). The HBII required more clinician time [mean (SD), 72 (21) seconds per case], compared with Facogram, which did not require any clinician time. CONCLUSIONS: An automated, zone-specific facial analysis tool can eliminate clinician subjectivity and allow standardized assessment of facial paralysis.

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.

Post Facelift Facial Paralysis: A 20-Year Experience.

INTRODUCTION: Facial nerve (FN) injury during a facelift is a relatively rare but potentially devastating complication. Despite extensive literature discussing facial nerve anatomy and danger zones, few studies describe detailed management, FN exploration intraoperative findings, and outcome following post-facelift facial paralysis (PFFP). We review a 20-year experience in managing iatrogenic PFFP. METHODS: PFFP patients were retrospectively identified between 2002-2022. Demographic data, operative details from the facelift procedure, post-facelift facial function, medical and surgical management, intraoperative findings, and long-term outcome were analyzed. RESULTS: 25 patients who experienced PFFP were referred for evaluation over the past 20 years. Eight patients required FN exploration, of which 6 underwent nerve repair; all recovered to some degree, with 50% achieving essentially normal facial function. 14 patients underwent non-surgical management including physical therapy, chemodenervation and filler therapy. Of these non-surgical patients who were not lost to follow up, 50% achieved normal facial function and 42% achieved near-normal facial function. The single patient who had no spontaneous improvement presented outside the re-innervation window and was not an operative candidate. CONCLUSION: PFFP outcome depends on injury type and location, accurate assessment and appropriate treatment; however, overall prognosis is quite favorable. FN exploration is warranted when nerve transection is suspected. Observation is suitable for patients demonstrating early signs of recovery. Patients presenting beyond a reasonable re-innervation window will be offered other facial reanimation techniques. When FN exploration is required, outcomes may be superior in a facial nerve center setting. Adjunctive interventions for symmetry improvement while awaiting recovery are available.