One-stage procedure using spinal accessory nerve (XI)-innervated free muscle for facial paralysis reconstruction

Functional Outcome of Dual Reinnervation with Cross-Facial Nerve Graft and Masseteric Nerve Transfer for Facial Paralysis

BACKGROUND

The combination of cross-facial nerve graft (CFNG) and masseteric nerve transfer (MNT) for reinnervation of facial paralysis may provide advantages of both neural sources. However, quantitative functional outcome reports with a larger number of patients are lacking in the literature. Here, the authors describe their 8-year experience with this surgical technique.

METHODS

Twenty patients who presented with complete facial paralysis (duration, <12 months) received dual reinnervation with CFNG and MNT. The functional outcome of the procedure was evaluated with the physician-graded outcome metric eFACE scale. The objective artificial intelligence-driven software Emotrics and FaceReader were used for oral commissure measurements and emotional expression assessment, respectively.

RESULTS

The mean follow-up was 31.75 ± 23.32 months. In the eFACE score, the nasolabial fold depth and oral commissure at rest improved significantly ( P < 0.05) toward a more balanced state after surgery. Postoperatively, there was a significant decrease in oral commissure asymmetry while smiling (from 19.22 ± 6.1 mm to 12.19 ± 7.52 mm). For emotional expression, the median intensity score of happiness, as measured by the FaceReader software, increased significantly while smiling (0.28; interquartile range, 0.13 to 0.64). In five patients (25%), a secondary static midface suspension with fascia lata strip had to be performed because of unsatisfactory resting symmetry. Older patients and patients with greater preoperative resting asymmetry were more likely to receive static midface suspension.

CONCLUSION

The authors' results suggest that the combination of MNT and CFNG for reinnervation of facial paralysis provides good voluntary motion and may lessen the use of static midface suspension in the majority of patients.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Neurofibromatosis Type II and Facial Paralysis: Clinical Evaluation and Management

BACKGROUND

Facial paralysis secondary to neurofibromatosis type 2 (NF2) presents the reconstructive surgeon with unique challenges because of its pathognomonic feature of bilateral acoustic neuromas, involvement of multiple cranial nerves, use of antineoplastic agents, and management. Facial reanimation literature on managing this patient population is scant.

METHODS

A comprehensive literature review was performed. All patients with NF2-related facial paralysis who presented in the past 13 years were reviewed retrospectively for type and degree of paralysis, NF2 sequelae, number of cranial nerves involved, interventional modalities, and surgical notes.

RESULTS

Twelve patients with NF2-related facial paralysis were identified. All patients presented after resection of vestibular schwannoma. Mean duration of weakness before surgical intervention was 8 months. On presentation, one patient had bilateral facial weakness, 11 had multiple cranial nerve involvement, and seven were treated with antineoplastic agents. Two patients underwent gracilis free functional muscle transfer, five underwent masseteric-to-facial nerve transfer (of whom two were dually innervated with a crossfacial nerve graft), and one patient underwent depressor anguli oris myectomy. Trigeminal schwannomas did not affect reconstructive outcomes if trigeminal nerve motor function on clinical examination was normal. In addition, antineoplastic agents such as bevacizumab and temsirolimus did not affect outcomes if stopped in the perioperative period.

CONCLUSIONS

Effectively managing patients with NF2-related facial paralysis necessitates understanding the progressive and systemic nature of the disease, bilateral facial nerve and multiple cranial nerve involvement, and common antineoplastic treatments. Neither antineoplastic agents nor trigeminal nerve schwannomas associated with normal examination affected outcomes.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, V.

Age-related outcomes of facial reanimation surgery using gracilis free functional muscle transfer innervated by the masseteric nerve: A retrospective cohort study

BACKGROUND

The free functional muscle gracilis transfer is an established approach in facial reanimation surgery; however, the significance of its neurotization and the patient's age is still inconclusive. Several donor nerves are available for facial reanimation using the free functional gracilis muscle transfer.

OBJECTIVE

This retrospective cohort study investigates whether the masseteric nerve is an equally reliable donor nerve in both older and younger patients.

METHODS

We included 46 patients (13-71 years, male and female) who underwent nerve-to-masseter (NTM)-driven free functional muscle transfer (FFMT) between January 2008 and December 2019. Patients were distributed into three cohorts according to their age at surgery. We assessed the facial symmetry before and after surgery using the pupillo-modiolar angle. Commissure height and excursion deviation were measured with the Emotrics software. Patient-reported outcome measurements were taken using the Facial Clinimetric Examination (FaCE) scale.

RESULTS

All patients had successful flap innervation, except for one patient in the middle-aged cohort (31-51 years). The postoperative facial symmetry at rest, smiling, and laughing was analyzed with the pupillo-modiolar angle and the Emotrics software and showed similar results between all cohorts. The FaCE scale showed similar scores for the middle-aged (31-51 years) cohort and the senior cohort (52-71 years). The social function score in the senior cohort was higher than in the middle-aged cohort, without statistical significance. One patient in the middle-aged (31-51 years) cohort and the senior cohort (52-71 years), respectively, underwent emergency revision due to impaired flap perfusion and could be salvaged.

CONCLUSIONS

NTM-driven FFMT for facial reanimation is a safe and reliable procedure across all age groups of patients.

Phrenic Nerve as an Alternative Donor for Nerve Transfer to Restore Shoulder Abduction in Severe Multiple Root Injuries of the Adult Brachial Plexus

PURPOSE

Nerve transfer is the gold standard to restore shoulder abduction in acute brachial plexus injuries. The aim of this study was to compare the phrenic nerve (Ph) to the spinal accessory nerve (XI) as the donor nerve for this purpose.

METHODS

A retrospective chart review was performed on 136 patients with acute brachial plexus injuries who received a nerve transfer of the shoulder with either the Ph (94 patients) or XI (42 patients). Each group was divided into 3 subgroups based on the recipient nerve. The maximum degree of shoulder abduction was recorded after 2 years of postoperative follow-up. A generalized estimating equation model was performed to examine the variables affecting shoulder abduction over time.

RESULTS

The maximum degrees of shoulder abduction achieved were 61.9° ± 38.7° in patients with Ph and 51.1° ± 37.3° in patients with XI. More than M3 shoulder abduction was achieved by 67% of patients with Ph versus 59% of patients with XI. The regression analysis showed that the age at the time of surgery correlated more with the functional outcome over time than the choice of donor nerve.

CONCLUSIONS

In multiple root brachial plexus injuries, the Ph exhibited similar outcomes to the XI for shoulder abduction. Our routine exploration of the supraclavicular plexus exposes the Ph conveniently for nerve transfer. The phrenic nerve should be considered as an alternative when the XI is not available or is reserved for secondary reconstruction.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

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.

Integrated Approaches for Reconstruction of Facial Paralysis

BACKGROUND

Facial paralysis can affect periorbital muscles, oral competence, and facial expressions with significant facial deformities, which could occur in either children or adults with variable severity, duration, and degree of recovery.

OBJECTIVE

The present study was aimed to delineate treatment plans for facial paralysis with different clinical scenarios and to report the results of these patients.

METHODS

Patients were grouped according to different presentations as follows: (1) facial paralysis with incomplete recovery; (2) young patients of facial paralysis without recovery; (3) senile patients of facial palsy without recovery; (4) combined facial palsy with mandibular deficiency, vascularized bone reconstruction for mandible with (a) subsequent muscle transfer or (b) simultaneous sling operation or (c) simultaneous facial nerve exploration and cross nerve grafting; (5) palsy of frontal branch of facial nerve; (6) palsy of zygomatic-buccal branch of facial nerve; (7) palsy of marginal mandibular branch of facial nerve; (8) partial recovery with dyskinesia; and (9) facial paralysis with dynamic asymmetry and muscle atrophy. According to clinical scenarios, different treatment plans were provided, and clinical outcomes were evaluated and presented.

RESULTS

All patient groups achieved fair or satisfactory outcomes. Revisions using sling procedures, botulinum toxin injection, and filler or fat graft as supplement further refined the ultimate outcomes.

CONCLUSIONS

For reconstruction of facial paralysis, individualized integrated treatment plans are mandatory according to the presentation and condition of the patient. Comprehensive considerations and strategic solutions for the existing disabilities have been appreciated by the patients. The least numbers of operations with considerate correction of asymmetry were the major concerns of the patients.

The Split Hypoglossal Nerve and Cross-Face Nerve Graft for Dual Innervation of the Functional Muscle Transfer in Facial Reanimation

Facial paralysis is a disabling deformity. The affected individual is seriously affected both esthetically and functionally. Free functional muscle transfer is currently the corner stone in the management of long-standing facial nerve paralysis. Several nerve options are available to supply the free muscle transfer. These nerves can be used alone or in combination. The aim of this work is to study the possibility and results of dually innervating the free functioning muscle transfer. The dual innervation is done using the split hypoglossal nerve and cross-face nerve graft (CFNG) both sutured in an end-to-end manner to the nerve to gracilis. Twenty-nine patients with unilateral long-standing facial nerve paralysis (more than 1 y) were treated using free gracilis muscle transfer dually supplied by the split hypoglossal nerve and CFNG, both sutured in an end-to-end manner. The gained excursion after the free gracilis transfer was 9 to 29 mm (mean: 17.24 mm). A statistically significant increase ( P -value=0.0001) in the distance from where the midline crosses the lower vermilion border to commissure occurred from preoperative (mean: 16.55 mm) to postoperative setting (mean: 33.79 mm). Spontaneity was achieved in 26 patients (89.6%). In conclusion, dual innervation of the free muscle transfer using both the split hypoglossal nerve and CFNG (both sutured in an end-to-end manner to the nerve to gracilis) is a good possible option to treat long-standing cases of facial nerve paralysis. It yields adequate muscle excursion with acceptable spontaneity.

Surgical Treatment for Postparalytic Facial Synkinesis - A 35 Year Experience

BACKGROUND

Surgical intervention with Combined myectomy & neurectomy followed by functioning free muscle transplantation (FFMT) has been proposed to effectively resolve the problem of postparalytic facial synkinesis (PPFS) since 1985, and continues to be our standard-of-care. We aim to provide evidence that this surgical strategy is effective for treatment of synkinesis and smile quality.

METHODS

103 patients with PPFS were investigated (1985-2020). They all underwent extensive removal of the synkinetic muscles and triggered facial nerve branches in the cheek, nose and neck regions, followed by gracilis FFMT for facial reanimation. Ninety-four patients with 50 Type II and 44 Type III PPFS patients, all of whom had at least one year of postoperative follow-up were included in the study. Patient's demographics, 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% prior to 2012 up to 24% in the years after. Young adults (79%) and female patients (63%) 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-A toxin injection after surgery. Revision surgery for secondary deformity was 53%.

CONCLUSION

Combined myectomy & neurectomy followed by FFMT 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.

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.

Sternocleidomastoid Muscle Transfer for Treatment of Longstanding Facial Paralysis: Long-term Outcomes and Complications

BACKGROUND/AIM

The use of sternocleidomastoid muscle (SCM) flap for facial reanimation was established in the 1980s by the senior author of this paper. We aimed to analyze long-term outcome and complications of this procedure.

PATIENTS AND METHODS

We conducted a retrospective chart review of all patients undergoing SCM reanimation for longstanding facial palsy between January 2009 and December 2015. Patients with follow-up longer than 12 months (range=12-96) were included in the study. Facial muscle function was evaluated before and at each follow-up after the surgery with the House-Brackmann (HB) scale-facial nerve grading system and Facegram analysis. Donor site morbidity and overall complication rates were documented and analyzed.

RESULTS

Forty-two patients aged 18-66 years (mean age=37) with a mean duration of facial palsy of 5 years (range=2-48) met the inclusion criteria. The HB score 2 years after surgery improved significantly (p<0.05) in comparison to the pre-operative condition (3.6 vs. 4.7). Twelve months after surgery, oral commissure excursion improved by mean 8.95 mm. No flap necrosis occurred, nor compromise of neck and shoulder function despite an obvious contour defect in the SCM donor site. None of the patients presented head posture or movement issues.

CONCLUSION

The SCM flap transfer is a reliable and effective procedure to achieve moderate improvement of the oral commissure excursion using a local method with moderate donor site morbidity. It can be regarded as a valuable option for dynamic facial reanimation in case of longstanding facial palsy.

End-to-Trunk Masseteric to Facial Nerve Transfer With Selective Neurectomy for Facial Reanimation

OBJECTIVE

To examine functional outcomes following end-to-trunk masseteric to facial nerve transfer in patients with chronic flaccid facial paralysis.

DESIGN

Retrospective chart review.

SETTING

Tertiary-care private practice setting.

PARTICIPANTS

Patients with complete unilateral facial paralysis of less than 24 months duration.

INTERVENTIONS

Direct end-to-trunk masseteric to facial nerve anastomosis.

OUTCOME MEASURES

Outcome measures included time to first movement, development of synkinesis, and an objective assessment of the resting tone and dynamic movement that was achieved.

RESULTS

Patient age at the time of transfer ranged from 6 to 61. Follow-up ranged from 12 to 24 months. No patients had any perioperative complications. No patient experienced significant mass movement or synkinetic facial movement with chewing. No patient had worsened chewing or swallowing. Patients have not yet recovered significant resting tone. All patients achieved smile activity when biting down with a median (interquartile range) oral commissure excursion of 7.57 mm (5.19-9.94 mm), starting 3 to 5 months after transfer.

CONCLUSIONS

End-to-trunk masseteric to facial nerve transfer is a safe and effective procedure. Patients had rapid reinnervation with good excursion and achieved a natural appearing smile. The rehabilitated smile appears better than that achieved with hypoglossal-facial nerve transfer. The procedure can be performed coincident with cross-facial nerve grafting, and in some cases may produce dynamic facial movement that obviates the need for free muscle transfer.

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.

Hemihypoglossal-facial nerve anastomosis: results and electromyographic characterization

INTRODUCTION

The facial nerve surgery belongs to the basic procedures during lateral skull base approaches. Its damage has serious medical and psychological consequences, and therefore mastery of reconstruction and correction techniques should belong to the repertoire of skull base surgeons. The goal of this study was to demonstrate usefulness of electromyographic follow-up in facial nerve reconstruction.

MATERIAL AND METHODS

A total of 16 patients underwent hemihypoglossal-facial anastomosis between 2005 and 2017. Most of the primary lesions came from vestibular schwannoma surgery. All patients were examined with electromyography and scored according to the House-Brackmann and IOWA grading scales. Function of the tongue has been evaluated.

RESULTS

Ten patients achieved definitive House-Brackmann grade 3 score (62.5%). We did not observe any association with the patient's age, previous irradiation and the etiology of the damage. Electromyography showed pathological spontaneous activity after the first surgery. Incipient regeneration potentials were detected in 4-17 months (average 7.6) and reached maximum in 6.5-18 months (average 16). Electromyographic assessment of the effect of tongue movement showed better mimic voluntary activity by swallowing or by moving the tongue up. There was no relationship between the start of activity and the interval to achieving maximal activity.

CONCLUSION

Hemihypoglossal-facial nerve anastomosis is a safe procedure and it is an optimal solution for cases lacking a proximal stump or in the case of reconstruction in the second stage. Electromyography can predict initial reinnervation activity after reconstructive procedures. During subsequent follow-up it can help to discover insufficiently recovering patients, however clinical characteristics are crucial.

Nerve to the Zygomaticus Major Muscle for Facial Reanimation Surgery: A Cadaveric Study for Branching Patterns and Axonal Count

Background

In facial reanimation surgery, higher donor facial nerve axonal load yields a superior outcome. Nerves supplying the zygomaticus major muscle are primary donors for the grafting procedure; however, their topography has not been studied in detail. This study identified potential donor nerves by quantifying axon loads of the zygomaticus major muscle through histological analysis of cadaveric specimens.

Materials and Methods

Forty-three hemifaces from 26 fresh human cadavers were studied. Branching patterns of nerves were classified according to their shapes. All branches of interest were sectioned and stained for an axon count. The potential donors were mapped into each tributary of nerves supplying the zygomaticus major.

Results

Branching patterns were categorized into five types: Y-type (28%), X-type (28%), H-type (19%), E-type (14%), and F-type (11%). The mean number of axons in the most superiorly and proximally located main branches was 1387.33 ± 406.59 in Y-type, 1021.42 ± 187.79 in X-type, 1222.75 ± 193.82 in H-type, 1496.17 ± 364.567 in E-type, and 1353.40 ± 256.07 in F-type (P > 0.05). A topographic relation between facial nerves supplying the zygomaticus major muscle and their mean axonal load was illustrated. The zygomatic/buccal branches were found within 5 mm from Zuker's point in 100% of X-, Y-, H-, and E-type and 75% of F-type specimens.

Conclusions

Most proximal facial nerve branches supplying the zygomaticus major, arising at the anterior border of a parotid gland, contained over 900 axons in all five branching types. The primary subbranches may be used in selected cases if donor weakness is a concern. Further, our study provides evidence that demonstrates the precision of Zuker's point.

Impact of increasing age on functioning free muscle transplantation for facial palsy reconstruction

BACKGROUND

Management of facial paralysis in older patients is controversial. The purpose of this study is to evaluate the impact of increasing age on functioning free muscle transplantation (FFMT).

PATIENTS AND METHODS

Twenty-nine facial paralysis patients over 50 years old received FFMT. A separate group of patients aged 41-50 years old were included as control. Outcome assessments included use of the SMILE evaluation system for excursion, a cortical adaptation scoring system for brain plasticity, and a subjective satisfaction assessment score. Meta-analysis of literature over the past 50 years was also performed to examine the impact of older age.

RESULTS

The mean change in excursion movement was 13.39 ± 5.49 mm. Weakest excursion was found in the oldest age group (11.74 ± 4.84 mm, p = .097), in concordance with the meta-analysis. There was significant difference between the three different neurotizers (p = .036). Excursion and satisfaction score were significantly worse in the older cohort with the cross face-nerve graft FFMT.

CONCLUSIONS

FFMT is a viable option in the elderly patient group but performs weaker in excursion. The choice of neurotizer is dependent on the patient's goals and the suitable age at which the benefits outweigh the risks.

Effectiveness and safety of the use of gracilis muscle for dynamic smile restoration in facial paralysis: A systematic review and meta-analysis

BACKGROUND

Smiling is a fundamental component of social interactions. Significant challenges arise for patients with facial palsy. One of the key procedures for dynamic smile restoration is the microneurovascular transfer of a gracilis muscle. We aimed to assess the effectiveness and safety of dynamic smile reanimation surgery using the free gracilis muscle unit in patients with facial palsy.

METHODS

We conducted a systematic review and meta-analysis of studies reporting surgical outcomes of dynamic smile restoration using free gracilis muscles identified from EMBASE, Medline, and Web of Science databases from their inception to March 15, 2018. Two-stage screening and data extraction were performed by two independent reviewers. Pooled proportions were calculated using random-effects models.

RESULTS

Thirty-one studies including 1647 patients who underwent 1739 free gracilis flaps were included. Twelve (38.7%) studies measured perioperative smile excursion change using six different tools. Six of these studies were homogeneous and were used in meta-analyses of smile excursion improvement, which revealed a mean change of 7.5 mm (95% CI 6.0-9.0 mm, I² 86.7%) perioperatively. Twenty (64.5%) studies reported perioperative complications, and pooled proportions of flap failures were of 2.9% (95% CI 1.3-4.5%, I² 47.7%).

CONCLUSIONS

Dynamic smile restoration using a free gracilis muscle may represent an effective procedure to regain oral commissure motion and is associated with an approximately 3% rate of flap failure. Masseteric nerve coaptations lead to larger improvements in perioperative smile excursion (10 mm) than cross-facial nerve grafts (6.8 mm). Future studies with homogeneous reporting of smile excursion and patient-reported outcome measures are needed.

Facial reanimation with masseter nerve-innervated free gracilis muscle transfer in established facial palsy patients

Background

The masseter nerve is a useful donor nerve for reconstruction in patients with established facial palsy, with numerous advantages including low morbidity, a strong motor impulse, high reliability, and fast reinnervation. In this study, we assessed the results of masseter nerve–innervated free gracilis muscle transfer in established facial palsy patients.

Methods

Ten patients with facial palsy who received treatment from January 2015 to January 2017 were enrolled in this study. Three patients received masseter nerve–only free gracilis transfer, and seven received double-innervated free gracilis transfer (masseter nerve and a cross-face nerve graft). Patients were evaluated using the Facial Assessment by Computer Evaluation software (FACEgram) to quantify oral commissure excursion and symmetry at rest and when smiling after muscle transfer.

Results

The mean time between surgery and initial movement was roughly 167.7 days. A statistically significant increase in excursion at rest and when smiling was seen after muscle transfer. There was a significant increase in the distance of oral commissure excursion at rest and when smiling. A statistically significant increase was observed in symmetry when smiling. Terzis’ functional and aesthetic grading scores showed significant improvements postoperatively.

Conclusions

Masseter nerve innervation is a good option with many uses in in established facial palsy patients. For some conditions, it is the first-line treatment. Free gracilis muscle transfer using the masseter nerve has excellent results with good symmetry and an effective degree of recovery.

Outcome Tracking in Facial Palsy

Outcome tracking in facial palsy is multimodal, consisting of patient-reported outcome measures, clinician-graded scoring systems, objective assessment tools, and novel tools for layperson and spontaneity assessment. Patient-reported outcome measures are critical to understanding burden of disease in facial palsy and effects of interventions from the patient perspective. Clinician-graded scoring systems are inherently subjective and no 1 single system satisfies all needs. Objective assessment tools quantify facial movements but can be laborious. Recent advances in facial recognition technology have enabled automated facial measurements. Novel assessment tools analyze attributes such as spontaneous smile, emotional expressivity, disfigurement, and attractiveness as determined by laypersons.

Proximal versus Distal Nerve Transfer for Biceps Reinnervation-A Comparative Study in a Rat's Brachial Plexus Injury Model

BACKGROUND

The exact role of proximal and distal nerve transfers in reconstruction strategies of brachial plexus injury remains controversial. We compared proximal with distal nerve reconstruction strategies in a rat model of brachial plexus injury.

METHODS

In rats, the C6 spinal nerve with a nerve graft (proximal nerve transfer model, n = 30, group A) and 50% of ulnar nerve (distal nerve transfer model, n = 30, group B) were used as the donor nerves. The targets were the musculocutaneous nerve and the biceps muscle. Outcomes were recorded at 4, 8, 12, and 16 weeks postoperatively. Outcome parameters included grooming test, biceps muscle weight, compound muscle action potentials, tetanic contraction force, and axonal morphology of the donor and target nerves.

RESULTS

The axonal morphology of the 2 donor nerves revealed no significant difference. Time interval analysis in the proximal nerve transfer group showed peak axon counts at 12 weeks and a trend of improvement in all functional and physiologic parameters across all time points with statistically significant differences for grooming test, biceps compound action potentials, tetanic muscle contraction force, and muscle weight at 16 weeks. In contrast, in the distal nerve transfer group, the only statistically significant difference was observed between the 4 and 8 week time points, followed by a plateau from 8 to 16 weeks.

CONCLUSIONS

Outcomes of proximal nerve transfers are ultimately superior to distal nerve transfers in our experimental model. Possible explanations for the superior results include a reduced need for cortical adaptation and higher proportions of motor units in the proximal nerve transfers.

The Spinal Accessory Nerve for Functional Muscle Innervation in Facial Reanimation Surgery: An Anatomical and Histomorphometric Study

INTRODUCTION

Facial reanimation surgery is performed in severe cases of facial palsy to restore facial function. In a 1-stage procedure, the spinal accessory nerve can be used as a donor nerve to power a free gracilis muscle transplant for the reanimation of the mouth. The aim of this study was to describe the surgical anatomy of the spinal accessory nerve, provide a guide for reliable donor nerve dissection, and analyze the available donor axon counts.

METHODS

Dissections were performed on 10 nonembalmed cadavers (measurements of 20 nerves). Surgical anatomy of the spinal accessory nerve was described and distances to important landmarks were measured. Nerve biopsies were obtained of the main nerve trunk distal to the skull base, caudoposterior to the sternocleidomastoid muscle, proximal to the trapezius muscle and at the level of donor nerve harvest to analyze the myelinated axon count throughout the course of the spinal accessory nerve. The donor nerve length and available donor nerve axon count were the primary outcome parameters in this study.

RESULTS

The mean donor nerve length was 11.6 cm. The spinal accessory nerve was transferred to the mandibular angle without tension for ideal coaptation to the free muscle transplant. After retraction of the trapezius muscle, a small distal nerve branch that leaves the main nerve trunk at a 90-degree angle medially was used as a landmark to indicate the level of donor nerve transection. On average, 1400 myelinated donor axons were available for innervation of the gracilis muscle transplant.

CONCLUSIONS

This study gives a practical guide for spinal accessory nerve dissection for its application in facial reanimation as a motor source for the innervation of a free muscle transplant.

Postparalysis facial synkinesis: clinical classification and surgical strategies

Supplemental Digital Content is available in the text.

Background:

Postparalysis facial synkinesis (PPFS) can occur after any cause of facial palsy. Current treatments are still inadequate. Surgical intervention, instead of Botox and rehabilitation only, for different degrees of PPFS was proposed.

Methods:

Seventy patients (43 females and 27 males) with PPFS were enrolled since 1986. They were divided into 4 patterns based on quality of smile and severity of synkinesis. Data collection for clinically various presentations was made: pattern I (n = 14) with good smile but synkinesis, pattern II (n = 17) with acceptable smile but dominant synkinesis, pattern III (n = 34) unacceptable smile and dominant synkinesis, and pattern IV (n = 5) poor smile and synkinesis. Surgical interventions were based on patterns of PPFS. Selective myectomy and some cosmetic procedures were performed for pattern I and II patients. Extensive myectomy and neurectomy of the involved muscles and nerves followed by functioning free-muscle transplantation for facial reanimation in 1- or 2-stage procedure were performed for pattern III and many pattern II patients. A classic 2-stage procedure for facial reanimation was performed for pattern IV patients.

Results:

Minor aesthetic procedures provided some help to pattern I patients but did not cure the problem. They all had short follow-up. Most patients in patterns II (14/17, 82%) and III (34/34, 100%) showed a significant improvement of eye and smile appearance and significant decrease in synkinetic movements following the aggressively major surgical intervention. Nearly, all of the patients treated by the authors did not need repeated botulinum toxin A injection nor require a profound rehabilitation program in the follow-up period.

Conclusions:

Treatment of PPFS remains a challenging problem. Major surgical reconstruction showed more promising and long-lasting results than botulinum toxin A and/or rehabilitation on pattern III and II patients.

Update in facial nerve paralysis: tissue engineering and new technologies

PURPOSE OF REVIEW

To present the recent advances in the treatment of facial paralysis, emphasizing the emerging technologies. This review will summarize the current state of the art in the management of facial paralysis and discuss the advances in nerve regeneration, facial reanimation, and use of novel biomaterials. This review includes surgical innovations in reinnervation and reanimation as well as progress with bioelectrical interfaces.

RECENT FINDINGS

The last decade has witnessed major advances in the understanding of nerve injury and approaches for management. Key innovations include strategies to accelerate nerve regeneration, provide tissue-engineered constructs that may replace nonfunctional nerves, approaches to influence axonal guidance, limiting of donor-site morbidity, and optimization of functional outcomes. Approaches to muscle transfer continue to evolve, and new technologies allow for electrical nerve stimulation and use of artificial tissues.

SUMMARY

The fields of biomedical engineering and facial reanimation increasingly intersect, with innovative surgical approaches complementing a growing array of tissue engineering tools. The goal of treatment remains the predictable restoration of natural facial movement, with acceptable morbidity and long-term stability. Advances in bioelectrical interfaces and nanotechnology hold promise for widening the window for successful treatment intervention and for restoring both lost neural inputs and muscle function.