Patient experience in nerve-to-masseter-driven smile reanimation

Masseteric Nerve Transfer for Facial Paralysis Secondary to Parotid Malignancy: A Retrospective Case Series

Background: The objective outcomes of masseteric nerve transfer in the setting of parotid malignancy are unclear. Objective: To measure objective facial reanimation outcomes of masseteric nerve transfer in patients with parotid malignancy who underwent parotidectomy with facial nerve resection. Materials and Methods: Retrospective review of patients who underwent masseteric nerve transfer for facial paralysis secondary to parotid malignancy was carried out at a tertiary referral hospital from August 2017 to November 2021. Objective facial reanimation outcomes were analyzed using Emotrics. Minimal follow-up of 6 months was required for inclusion. Results: Eight patients (five males) with a median age of 75.5 years (range 53-91) met inclusion criteria. Fifty percent had metastatic squamous cell carcinoma, and 50% had primary parotid malignancy. Five patients underwent concomitant cancer resection with facial nerve reconstruction. Seven patients received postoperative adjuvant radiotherapy. After reinnervation, patients had improved oral commissure excursion (from 1.51 mm ±1.27 to 3.77 mm ±1.81; p < 0.01) and facial symmetry during smile. Conclusion: In this study, masseteric nerve transfer enhanced oral commissure excursion and facial symmetry during smile in patients with parotid malignancy and facial nerve resection.

Donor nerve selection in free gracilis muscle transfer for facial reanimation. A systematic review and meta-analysis of clinical outcomes

BACKGROUND

One of the critical factors in facial reanimation is selecting the donor nerve. The most favored neurotizers are the contralateral facial nerve with a cross-face nerve graft (CFNG) and motor nerve to the masseter (MNM). A relatively new dual innervation (DI) method has shown successful results. This study aimed to compare the clinical outcomes of different neurotization strategies for free gracilis muscle transfer (FGMT).

METHODS

The Scopus and WoS databases were queried with 21 keywords. Three-stage article selection was performed for the systematic review. Articles presenting quantitative data for commissure excursion and facial symmetry were included in meta-analysis, using random-effects model. ROBINS-I tool and Newcastle-Ottawa scale were used to assess bias and study quality.

RESULTS

One hundred forty-seven articles containing FGMT were systematically reviewed. Most studies indicated CFNG as the first choice. MNM was primarily indicated in bilateral palsy and in elderly. Clinical outcomes of DI studies were promising. 13 studies including 435 observations (179 CFNG, 182 MNM, 74 DI) were eligible for meta-analysis. The mean change in commissure excursion was 7.15 mm (95% CI: 4.57-9.72) for CFNG, 8.46 mm (95% CI: 6.86-10.06) for MNM, and 5.18 mm (95% CI: 4.01-6.34) for DI. In pairwise comparisons, a significant difference was found between MNM and DI (p = 0.0011), despite the superior outcomes described in DI studies. No statistically significant difference was found in resting and smile symmetry (p = 0.625, p = 0.780).

CONCLUSIONS

CFNG is the most preferred neurotizer, and MNM is a reliable second option. Outcomes of DI studies are promising, but more comparison studies are needed to draw conclusions. Our meta-analysis was limited by incompatibility of the assessment scales. Consensus on a standardized assessment system would add value to future studies.

Automated Spontaneity Assessment after Smile Reanimation: A Machine Learning Approach

BACKGROUND

Recreation of a spontaneous, emotional smile remains a paramount goal of smile reanimation surgery. However, optimal techniques to reliably restore spontaneity remain unknown. Dual automated machine-learning tools were used to develop an objective tool to analyze spontaneous smiling. The feasibility of this tool was tested in a sample of functional free muscle transfers.

METHODS

Validated humorous videos were used to elicit spontaneous smiles. Automated facial landmark recognition (Emotrics) and emotion detection software (Affdex) were used to analyze video clips of spontaneous smiling in nine normal subjects and 39 facial reanimation cases. Emotionality quotient was used to quantify the ability of spontaneous smiles to express joy.

RESULTS

The software could analyze spontaneous smiling in all subjects. Spontaneous smiles of normal subjects exhibited median 100 percent joy and 0 percent negative emotion (emotional quotient score, +100/0). Spontaneous smiles of facial palsy patients after smile reanimation, using cross-facial nerve graft, masseteric nerve, and dual innervation, yielded median emotional quotient scores of +82/0, 0/-48, and +10/-24 respectively (joy, p = 0.006; negative emotion, p = 0.034).

CONCLUSIONS

Computer vision software can objectively quantify spontaneous smiling outcomes. Of the retrospective sample of cases reviewed in this study, cross-facial nerve graft-innervated gracilis functional free muscle transfer achieved a greater degree of emotionality during spontaneous smiling than masseteric or dually innervated transfer. Quantification of spontaneous smiling from standard video clips could facilitate future, blinded, multicenter trials with sufficient long-term follow-up to definitively establish the rates of spontaneity from a range of reanimation procedures.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Diagnostic, IV.

Factors Associated With Late Admission to Facial Plastic Surgery Among Patients With Long-Standing Facial Paralysis

BACKGROUND

Facial plastic surgeons often encounter patients experiencing untreated long-standing facial paralysis who are unaware that their condition can be managed by facial reconstructive procedures. To promote timely admission of patients with facial paralysis for facial plastic surgery, factors associated with late admission should be elucidated.

METHODS

A retrospective chart review was conducted on patients admitted to our facial paralysis clinic. Late admission was defined by an onset-to-admission interval longer than the median value. Multivariable logistic regression analysis was used to assess the odds ratio of late admission with age, sex, etiology, referring physician specialty, and the time of first admission.

RESULTS

A total of 199 cases from October 2017 to March 2020 were included. Onset-to-admission interval longer than 21 months (median) was considered late admission. Etiologies involving benign tumors and congenital diseases were significantly associated with late admission (odds ratio [95% confidence interval], 3.9 [1.0-14.4] and 31.7 [4.7-212.6], respectively). Most benign tumor cases were referred from nonplastic surgeons.

CONCLUSIONS

Benign tumors and congenital diseases were significantly related to late admission of patients with long-standing facial paralysis. As the majority of benign cases were referred from nonplastic surgeons, spreading awareness on facial plastic surgery as a treatment option may be necessary in promoting timely admission.

[Dynamic procedures for facial nerve reconstruction]

In this article the indications and surgical treatment options for patients with facial nerve palsy are discussed. A distinction is made between static and dynamic surgical procedures. Static reconstructions for example are used to restore the eyelid closure function. For smile reconstruction, which is important for the psychosocial life of the patient, dynamic procedures are used. Depending on the duration of the facial nerve paralysis, there are several possibilities to restore the smile. In this work the masseteric branch transposition to the buccal branch, the hypoglossal-facial nerve anastomosis, the Labbé procedure and the gracilis flap as a free muscle transplant are discussed. The surgical procedures are compared and the advantages and disadvantages of the intervention are presented. A spontaneous smile is aimed, this cannot always be achieved. With the masseteric branch transposition to the buccal branch and the Labbé procedure the smile is initially triggered by chewing. A spontaneous smile is possible through cortical adaptation. With the gracilis flap, however, a nerve anastomosis with the contralateral 'healthy' facial nerve is possible, either directly or via a so-called cross facial nerve grafting, whereby a spontaneous smile can be achieved.

Therapists' perceptions and attitudes in facial palsy rehabilitation therapy: A mixed methods study

Background: Facial palsy rehabilitation therapy plays an essential role in treating facial palsy.Purpose: This study aimed to gain insight into therapists' perceptions and attitudes toward facial palsy rehabilitation therapy and to examine whether therapists could be categorized into distinct groups based on these attitudes and perceptions.Methods: Thirteen semi-structured, in-depth interviews were conducted in a purposive sample of therapists. Interviews were analyzed using thematic analysis. Next, a questionnaire containing questions about therapists' characteristics and perceptions and attitudes toward facial palsy rehabilitation therapy was sent to all facial palsy rehabilitation therapists in the Netherlands and Flanders (n = 292). Latent class analysis (LCA) was performed to identify and analyze distinct groups of therapists.Results: Seven themes were derived from the interviews: treatment goals, therapy content, indications, measurement instruments, factors influencing success, emotional support, and cooperation with colleagues. The questionnaire was filled out by 127 therapists. A 2-group structure consisting of a positive class and a negative class was found to fit the questionnaire data best. No distinction could be made regarding therapists' characteristics.Conclusion: Considerable variation in stated treatment practices was present among therapists. Therapists could be classified into 2 groups. This study raises several hypotheses that require further study.

Dermal Filler Treatment Improves Psychosocial Well-Being in Facial Paralysis Patients

Background: In the care of the facial paralysis (FP) patient, outcomes have historically focused on facial function rather than the psychosocial burden of the disease state. Yet, FP patients often describe the impact of their disease on domains of psychosocial health. These patient concerns have motivated clinicians to formally recognize and treat nonfunctional sequelae of the disease. Dermal filler therapy (DFT) is a minimally invasive reversible procedure that can be used to treat facial asymmetry and improve psychosocial well-being in FP patients. However, there are no data describing outcomes of DFT in FP-related facial asymmetry. Therefore, we sought to formally characterize FP patients' facial symmetry and psychosocial well-being before and after DFT. Methods: FP patients presenting for DFT at a tertiary academic medical center were prospectively interviewed. Patients completed the validated FACE-Q for Appearance-Related Psychosocial Distress instrument. Self-reported facial symmetry scores were recorded. Patients were evaluated before and 2 weeks after DFT. Statistical analysis was performed on R software using paired sample t-tests. Results: Twenty FP patients completed DFT treatment and two surveys. The cohort was predominantly female (n = 19, 95%) with an average age of 54 years. After a single treatment of DFT averaging 2.3 mL, patients had significant improvement in facial symmetry and psychosocial well-being. Patients felt particular improvement in self-confidence and emotional expression (p < 0.0001 for all stated comparisons). Conclusion: FP of varying etiologies is associated with significant functional, psychosocial, and quality-of-life impairments. This is the first prospective study to demonstrate statistically significant improvements in facial symmetry and psychosocial well-being after a single office-based treatment of dermal filler. In addition, our study's emphasis on psychosocial health instruments reflects an increased awareness of this important domain in the care of the FP patient.

Spontaneity Assessment in Dually Innervated Gracilis Smile Reanimation Surgery

Importance

Surgeons have sought to optimize outcomes of smile reanimation surgery by combining inputs from nerve-to-masseter and cross-face nerve grafts. An objective assessment tool could help surgeons evaluate outcomes to determine the optimal neural sources for smile reanimation.

Objective

To evaluate the use of a novel video time-stamping method and standard outcome measurement tools to assess outcomes of facial reanimation surgery using various innervation strategies.

Design, Setting, and Participants

Cohort study assessing the outcomes of dually innervated gracilis free muscle transfers vs single-source innervated gracilis transfer performed at a tertiary care facial nerve center between 2007 and 2017 using a novel, video time-stamping spontaneity assessment method. The statistical analyses were performed in 2018.

Interventions

Dually innervated gracilis free muscle transfers or single-source innervated gracilis transfer.

Main Outcomes and Measures

Spontaneous smiling was assessed by clinicians and quantified using blinded time-stamped video recordings of smiling elicited while viewing humorous video clips.

Results

This retrospective cohort study included 25 patients (12 men and 13 women; median [range] age, 38.4 [29.3-46.0] years) treated with dually innervated gracilis free functional muscle graft for unilateral facial palsy between 2007 and 2017. Smile spontaneity assessment was performed in 17 patients and was compared with assessment performed in 24 patients treated with single-source innervated gracilis transfer (ie, nerve-to-masseter-driven or cross-face nerve graft-driven gracilis [n = 13]) (demographic data not available for NTM and CFNG cohorts). The use of time-stamped video assessment revealed that spontaneous synchronous oral commissure movement in a median percentage of smiles was 33% in patients with dually innervated gracilis (interquartile range [IQR], 0%-71%), 20% of smiles in patients with nerve-to-masseter-driven gracilis (IQR, 0%-50%), and 75% of smiles in patients with cross-face nerve graft-driven gracilis (IQR, 0%-100%). Clinicians graded smile spontaneity in dually innervated cases as absent in 40% (n = 6 of 15), trace in 33% (n = 5 of 15) and present in 27% (n = 4 of 15). No association was demonstrated between clinician-reported spontaneity and objectively measured synchronicity.

Conclusions and Relevance

Dually innervated gracilis free muscle transfers may improve smile spontaneity compared with masseteric nerve-driven transfers but not to the level of cross-face nerve graft-driven gracilis transfers. Quantifying spontaneity is notoriously difficult, and most authors rely on clinical assessment. Our results suggest that clinicians may rate presence of spontaneity higher than objective measures, highlighting the importance of standardized assessment techniques.

Level of Evidence

4.

Masseteric-to-Facial Nerve Transfer and Selective Neurectomy for Rehabilitation of the Synkinetic Smile

Importance

Synkinesis is the involuntary movement of 1 area of the face accompanying volitional movement of another; it is commonly encountered in patients affected by facial palsy. Current treatments for synkinesis include biofeedback for muscular retraining and chemodenervation via the injection of botulinum toxin. Chemodenervation is effective in reducing unwanted muscle movement, but it requires a commitment to long-term maintenance injections and may lose effectiveness over time. A permanent solution for synkinesis remains elusive.

Objective

To evaluate masseteric-to-facial nerve transfer with selective neurectomy in rehabilitation of the synkinetic smile.

Design, Setting, and Participants

In this case series, 7 patients at a tertiary care teaching hospital underwent masseteric-to-facial nerve transfer with selective neurectomy for synkinesis between September 14, 2015, and April 19, 2018. The medical records of these patients were retrospectively reviewed and demographic characteristics, facial palsy causes, other interventions used, and changes in eFACE scores were identified.

Intervention

Masseteric-to-facial nerve transfer.

Main Outcomes and Measures

Changes in eFACE scores (calculated via numeric scoring of many sections of the face, including flaccidity, normal tone, and hypertonicity; higher scores indicate better function and lower scores indicate poorer function) and House-Brackmann Facial Nerve Grading System scores (range, 1-6; a score of 1 indicates normal facial function on the affected side, and a score of 6 indicates absence of any facial function [complete flaccid palsy] on the affected side).

Results

Among the 7 patients in the study (6 women and 1 man; median age, 49 years [range, 41-63 years]), there were no postoperative complications; patients were followed up for a mean of 12.8 months after surgery (range, 11.0-24.5 months). Patients experienced a significant improvement in mean (SD) eFACE scores in multiple domains, including smile (preoperative, 65.00 [8.64]; postoperative, 76.43 [7.79]; P = .01), dynamic function (preoperative, 62.57 [15.37]; and postoperative, 75.71 [8.48]; P = .03), synkinesis (preoperative, 52.70 [4.96]; and postoperative, 82.00 [6.93]; P < .001), midface and smile function (preoperative, 60.71 [13.52]; and postoperative, 78.86 [14.70]; P = .02), and lower face and neck function (preoperative, 51.14 [16.39]; and postoperative, 66.43 [20.82]; P = .046). Preoperative House-Brackmann Facial Nerve Grading System scores ranged from 3 to 4, and postoperative scores ranged from 2 to 3; this change was not significant.

Conclusion and Relevance

This study describes the application of masseteric-to-facial nerve transfer with selective neurectomy for smile rehabilitation in patients with synkinesis, with statistically significant improvement in smile symmetry and lower facial synkinesis as measured with the eFACE tool. This technique may allow for long-term improvement of synkinesis and smile. This study is only preliminary, and a larger cohort will permit more accurate assessment of this therapeutic modality.

Level of Evidence

4.