Dynamic Restoration in Möbius and Möbius-Like Patients:

Current Treatments and Future Directions for Facial Paralysis

Facial palsy is a condition that affects the facial nerve, the seventh of the 12 cranial nerves. Its main function is to control the muscles of facial expression. This involves the ability to express emotion through controlling the position of the mouth, the eyebrow, nostrils, and eye closure. The facial nerve also plays a key role in maintaining the posture of the mouth and as such, people with facial paralysis often have problems with drooling, speech, and dental hygiene.Due to the devastating effects on the quality of life of individuals with facial palsy, there are a multitude of various treatment options for the paralyzed face. This article reviews current management strategies and points towards promising future directions for research in the field of facial reanimation.

Gracilis Muscle-Free Flap Objective Improvement of Oral Commissure Excursion in Facial Palsy Reanimation Surgery: Systematic Review and Meta-Analysis

Background: Facial palsy patients face significant challenges. Gracilis free flap transfer is a key procedure in facial reanimation. Objective: This study aims to analyze oral commissure excursion improvement after gracilis free flap transfer and the differences regarding donor nerve: cross-facial nerve graft (CFNG), hypoglossal or spinal accessory nerves, motor nerve to masseteric (MNTM), and most recently, double anastomosis using both the MNTM and CFNG. Methods: A systematic review and meta-analysis were conducted of studies reporting oral commissure excursion improvement after free gracilis muscle transfer. Pooled proportions were calculated using a random-effects model. Results: Eighteen studies, 453 patients, and 488 free gracilis flaps were included. The mean change in perioperative oral commissure excursion was 7.0 mm, for CFNG 7.2 mm, for MNTM 7.7, and for double anastomoses 5.5 mm. Conclusions: There is a significant improvement in oral commissure excursion after gracilis muscle-free flap. Unfortunately, we could not make definitive conclusions regarding the optimal choice of donor nerve.

Testing EEG functional connectivity between sensorimotor and face processing visual regions in individuals with congenital facial palsy

Moebius syndrome (MBS) is characterized by the congenital absence or underdevelopment of cranial nerves VII and VI, leading to facial palsy and impaired lateral eye movements. As a result, MBS individuals cannot produce facial expressions and did not develop motor programs for facial expressions. In the latest model of sensorimotor simulation, an iterative communication between somatosensory, motor/premotor cortices, and visual regions has been proposed, which should allow more efficient discriminations among subtle facial expressions. Accordingly, individuals with congenital facial motor disability, specifically with MBS, should exhibit atypical communication within this network. Here, we aimed to test this facet of the sensorimotor simulation models. We estimated the functional connectivity between the visual cortices for face processing and the sensorimotor cortices in healthy and MBS individuals. To this aim, we studied the strength of beta band functional connectivity between these two systems using high-density EEG, combined with a change detection task with facial expressions (and a control condition involving non-face stimuli). The results supported our hypothesis such that when discriminating subtle facial expressions, participants affected by congenital facial palsy (compared to healthy controls) showed reduced connectivity strength between sensorimotor regions and visual regions for face processing. This effect was absent for the condition with non-face stimuli. These findings support sensorimotor simulation models and the communication between sensorimotor and visual areas during subtle facial expression processing.

Degenerate pathway for processing smile and other emotional expressions in congenital facial palsy: an hdEEG investigation

Influential theoretical models argue that an internal simulation mechanism (motor or sensorimotor simulation) supports the recognition of facial expressions. However, despite numerous converging sources of evidence, recent studies testing patients with congenital facial palsy (i.e. Moebius syndrome) seem to refute these theoretical models. However, these results do not consider the principles of neuroplasticity and degeneracy that could support the involvement of an alternative neural processing pathway in these patients. In the present study, we tested healthy participants and participants with Moebius syndrome in a highly sensitive facial expression discrimination task and concomitant high-density electroencephalographic recording. The results, both at the scalp and source levels, indicate the activation of two different pathways of facial expression processing in healthy participants and participants with Moebius syndrome, compatible, respectively, with a dorsal pathway that includes premotor areas and a ventral pathway. Therefore, these results support the reactivation of sensorimotor representations of facial expressions (i.e. simulation) in healthy subjects, in the place of an alternative processing pathway in subjects with congenital facial palsy.

This article is part of the theme issue ‘Cracking the laugh code: laughter through the lens of biology, psychology and neuroscience’.

Prevalence of Hand Malformations in Patients With Moebius Syndrome and Their Management

BACKGROUND

Moebius syndrome is a disorder characterized by facial and abducens nerve paralysis. Patients can present a wide range of upper extremity malformations. Literature focused on orthopedic manifestations of Moebius syndrome shows variability in the prevalence and clinical presentation of upper extremity anomalies. The aim of this work is to evaluate the prevalence of upper extremity malformations in patients with Moebius syndrome, clarify its various clinical presentations, and present treatment strategies for their management.

METHODS

This is a retrospective, cross-sectional study including patients with Moebius syndrome and upper extremity malformations between 2012 and 2019. Data include demographic characteristics, Moebius syndrome subtype, type of malformation, affected extremity, and surgical procedures underwent. Quantitative data were recorded as mean (standard deviation [SD]), and qualitative data were expressed in terms of totals and percentages. Statistical association between Moebius syndrome subtype and development of upper extremity anomalies was evaluated using binary logistic regression.

RESULTS

Twenty-five out of 153 patients (16.3%) presented upper extremity malformations (48% male). Mean age of presentation was 9.08 ± 9.43 years. Sixty-eight percent of the malformations were unilateral. The most common presentations included Poland syndrome and simple syndactyly with 8 cases each (32%), followed by 5 cases of brachysyndactyly (20%), 3 cases of amniotic band syndrome (12%), and 1 case of cleft hand (4%). No statistical association was found between Moebius syndrome subtype and odds ratio for development of upper extremity anomalies. Thirteen patients (52%) underwent reconstructive procedures.

CONCLUSION

Poland syndrome and syndactyly are the most common anomalies in patients with Moebius syndrome. Patients may present with a wide range of hand malformations, each patient should be carefully evaluated in order to determine whether surgical treatment is needed and to optimize rehabilitation protocols.

Lessons from Gracilis Free Tissue Transfer for Facial Paralysis: Now versus 10 Years Ago

Outcomes following free gracilis muscle transfer have steadily improved during the past decade. Areas for continued improvement include re-creating natural smile vectors, improving midface symmetry, minimizing scarring, improving spontaneity, and increasing reliability using various neural sources. Outcome standardization, pooled data collection, and remote data acquisition methods will facilitate comparative effectiveness research and continued surgical advancements.

Workhorse Free Functional Muscle Transfer Techniques for Smile Reanimation in Children with Congenital Facial Palsy: Case Report and Systematic Review of the Literature

BACKGROUND

Pediatric facial palsy represents a rare multifactorial entity. Facial reanimation restores smiling, thus boosting self-confidence and social integration of the affected children. The purpose of this paper is to present a systematic review of microsurgical workhorse free functional muscle transfer procedures with emphasis on the long-term functional, aesthetic, and psychosocial outcomes.

MATERIALS AND METHODS

We performed a literature search of the PubMed database from 1995 to 2019 using the following search strategy: "facial paralysis"[Title/Abstract] OR "facial palsy"[Title]. We used as limits: full text, English language, age younger than 18 years, and humans. Two independent reviewers performed the online screening process using Covidence. Forty articles met the inclusion criteria. The protocol was aligned with the PRISMA statement (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and was registered at the International Prospective Register of Systematic Reviews (PROSPERO, CRD42019150112) of the National Institute for Health Research.

RESULTS

Free functional muscle transfer procedures include mainly segmental gracilis, latissimus dorsi, and pectoralis minor muscle transfer. Facial reanimation procedures with the use of the cross-face nerve graft (CFNG) or masseteric nerve result in almost symmetric smiles. The transplanted muscle grows harmoniously along with the craniofacial skeleton. Muscle function and aesthetic outcomes improve over time. All children presented improved self-esteem, oral commissure opening, facial animation, and speech.

CONCLUSIONS

A two-stage CFNG plus an FFMT may restore a spontaneous emotive smile in pediatric facial palsy patients. Superior results of children FFMT compared to adults FFMT are probably attributed to greater brain plasticity.

Moebius syndrome: Craniofacial clinical manifestations and their association with prenatal exposure to misoprostol

BACKGROUND

A growing link between prenatal exposure to misoprostol (PEM) and Moebius syndrome (MS) or sequence has been reported. Our objectives were to describe the craniofacial clinical manifestations associated with MS and to determine the frequency of PEM, comparing cases of exposure and nonexposure.

METHODS

A descriptive, cross-sectional study of 140 patients with MS. Clinical evaluations, as well as 140 interviews with mothers residing in 39 cities or districts of Colombia, were carried out between April 2008 and May 2018. Additionally, previous clinical history of each case was reviewed.

RESULTS

The average age of the patients with MS was 8.4 years (29 days to 48 years). All of them presented facial nerve involvement and abducens, 112 (80.8%) with bilateral facial paralysis. 98.5% presented craniofacial disorders, and there were no significant differences between those exposed and not exposed to misoprostol. Forty-seven percentage of patients (64 cases) presented PEM, in 98.4% of which abortion had been intended.

CONCLUSION

PEM could have an influence in the appearance of new cases of MS by increasing the frequency of bleeding during gestation, without increasing the number of associated craniofacial malformations. We present the biggest series on MS and craniofacial findings in the literature, along with a meaningful reference for its understanding.

LEVEL OF EVIDENCE

3b.

Orofacial motor dysfunction in Moebius syndrome

AIM

To review orofacial disabilities and their consequences in children with Moebius syndrome (MBS).

METHOD

We retrospectively analysed the records of 32 patients (21 males, 11 females) with non-progressive bilateral facial and abducens palsies who had been examined before 6 months of age.

RESULTS

All facial muscles were severely involved in 17 patients; in the 15 others, partial movements were found in the lower face. Most patients (n=24) were unable to smile. Patients frequently presented with congenital trismus (n=20) and drooling (n=18). Additional palsies involved cranial nerves IX and X (n=18) and XII (n=25). Sucking was absent or weak in 30 patients; swallowing was impaired in 25. During the first month of life, feeding disorders were graded as severe/moderate in 25. Respiratory complications occurred in 17. Severe feeding disorders were associated with congenital trismus (p=0.01) and with cranial nerve IX and X palsy (p=0.01). Growth failure between 1 and 6 months of age, followed by catch-up growth between 6 and 12 months, was observed in 20 patients. Between 2 and 5 years of age, 25 out of 32 patients attained normal oral diet and 28 out of 29 showed normal growth.

INTERPRETATION

Children with MBS frequently require adjusted therapeutic options to prevent failure to thrive. Congenital trismus, cranial nerve IX and X palsy, and laryngeal-tracheal dysfunctions are predictors of severe feeding disorders.

WHAT THIS PAPER ADDS

Moebius syndrome frequently induces reduced oral intake and early failure to thrive. Normal oral diet and growth parameters are attained at 2 to 5 years of age. Congenital trismus, pharyngeal palsy, and laryngeal disorders predict dysphagia.

Children with facial paralysis due to Moebius syndrome exhibit reduced autonomic modulation during emotion processing

BACKGROUND

Facial mimicry is crucial in the recognition of others' emotional state. Thus, the observation of others' facial expressions activates the same neural representation of that affective state in the observer, along with related autonomic and somatic responses. What happens, therefore, when someone cannot mimic others' facial expressions?

METHODS

We investigated whether psychophysiological emotional responses to others' facial expressions were impaired in 13 children (9 years) with Moebius syndrome (MBS), an extremely rare neurological disorder (1/250,000 live births) characterized by congenital facial paralysis. We inspected autonomic responses and vagal regulation through facial cutaneous thermal variations and by the computation of respiratory sinus arrhythmia (RSA). These parameters provide measures of emotional arousal and show the autonomic adaptation to others' social cues. Physiological responses in children with MBS were recorded during dynamic facial expression observation and were compared to those of a control group (16 non-affected children, 9 years).

RESULTS

There were significant group effects on thermal patterns and RSA, with lower values in children with MBS. We also observed a mild deficit in emotion recognition in these patients.

CONCLUSION

Results support "embodied" theory, whereby the congenital inability to produce facial expressions induces alterations in the processing of facial expression of emotions. Such alterations may constitute a risk for emotion dysregulation.

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.

Autonomic Responses to Emotional Stimuli in Children Affected by Facial Palsy: The Case of Moebius Syndrome

According to embodied simulation theories, others' emotions are recognized by the unconscious mimicking of observed facial expressions, which requires the implicit activation of the motor programs that produce a specific expression. Motor responses performed during the expression of a given emotion are hypothesized to be directly linked to autonomic responses associated with that emotional behavior. We tested this hypothesis in 9 children (M_age = 5.66) affected by Moebius syndrome (MBS) and 15 control children (M_age = 6.6). MBS is a neurological congenital disorder characterized by underdevelopment of the VI and VII cranial nerves, which results in paralysis of the face. Moebius patients' inability to produce facial expressions impairs their capacity to communicate emotions through the face. We therefore assessed Moebius children's autonomic response to emotional stimuli (video cartoons) by means of functional infrared thermal (fIRT) imaging. Patients showed weaker temperature changes compared to controls, suggesting impaired autonomic activity. They also showed difficulties in recognizing facial emotions from static illustrations. These findings reveal that the impairment of facial movement attenuates the intensity of emotional experience, probably through the diminished activation of autonomic responses associated with emotional stimuli. The current study is the first to investigate emotional responses in MBS children, providing important insights into the role of facial expressions in emotional processing during early development.

Congenital facial palsy and emotion processing: The case of Moebius syndrome

According to the Darwinian perspective, facial expressions of emotions evolved to quickly communicate emotional states and would serve adaptive functions that promote social interactions. Embodied cognition theories suggest that we understand others' emotions by reproducing the perceived expression in our own facial musculature (facial mimicry) and the mere observation of a facial expression can evoke the corresponding emotion in the perceivers. Consequently, the inability to form facial expressions would affect the experience of emotional understanding. In this review, we aimed at providing account on the link between the lack of emotion production and the mechanisms of emotion processing. We address this issue by taking into account Moebius syndrome, a rare neurological disorder that primarily affects the muscles controlling facial expressions. Individuals with Moebius syndrome are born with facial paralysis and inability to form facial expressions. This makes them the ideal population to study whether facial mimicry is necessary for emotion understanding. Here, we discuss behavioral ambiguous/mixed results on emotion recognition deficits in Moebius syndrome suggesting the need to investigate further aspects of emotional processing such as the physiological responses associated with the emotional experience during developmental age.

Management of Bilateral Facial Palsy

Bilateral facial paralysis is a rare entity that occurs in both pediatric and adult patients and can have congenital or acquired causes. When paralysis does not resolve with conservative or medical management, surgical intervention may be indicated. This article presents the authors' preferred technique for facial reanimation in patients with bilateral congenital facial paralysis. Specifically, a staged bilateral segmental gracilis transfer to ipsilateral nerve to masseter is discussed.

Pathogenesis of cranial neuropathies in Moebius syndrome: Electrodiagnostic orofacial studies

INTRODUCTION

We designed a retrospective study of 59 patients with congenital sporadic nonprogressive bilateral facial and abducens palsies.

METHODS

Examinations included needle electromyography (EMG) of facial and oral muscles, facial nerve motor latency and conduction velocity (FNCV), and blink responses (BR).

RESULTS

Neurogenic EMG changes were found in 1 or more muscles in 55 of 59 patients, with no abnormal spontaneous activity. EMG changes were homogeneously neurogenic in 17 patients, homogeneously myopathic in 1 patient, and heterogeneous in 41 of 59 patients. Motor latency was increased according to recordings from 52 of 137 facial muscles. An increase of motor latency was not associated with neurogenic EMG (Fischer's test: right, P = 1; left, P = 0.76). FNCV was slowed in 19 of 36 patients. BR was absent bilaterally in 35 of 58 patients; when present, R1 and R2 latencies were normal.

DISCUSSION

Our results support the hypothesis of an early developmental defect localized in motor cranial nerves with spared V-VII internuclear pathways. Muscle Nerve, 2018.

A proposal for new neurorehabilitative intervention on Moebius Syndrome patients after 'smile surgery'. Proof of concept based on mirror neuron system properties and hand-mouth synergistic activity

Studies of the last twenty years on the motor and premotor cortices of primates demonstrated that the motor system is involved in the control and initiation of movements, and in higher cognitive processes, such as action understanding, imitation, and empathy. Mirror neurons are only one example of such theoretical shift. Their properties demonstrate that motor and sensory processing are coupled in the brain. Such knowledge has been also central for designing new neurorehabilitative therapies for patients suffering from brain injuries and consequent motor deficits. Moebius Syndrome patients, for example, are incapable of moving their facial muscles, which are fundamental for affective communication. These patients face an important challenge after having undergone a corrective surgery: reanimating the transplanted muscles to achieve a voluntarily control of smiling. We propose two new complementary rehabilitative approaches on MBS patients based on observation/imitation therapy (Facial Imitation Therapy, FIT) and on hand-mouth motor synergies (Synergistic Activity Therapy, SAT). Preliminary results show that our intervention protocol is a promising approach for neurorehabilitation of patients with facial palsy.

Pre- and Postsurgical Orthodontics in Patients with Moebius Syndrome

The authors report a combined orthodontic-surgical correction of an adult patient's malocclusion affected by Moebius Syndrome (MS). The treatment was conducted at the Dentistry Unit and the Maxillofacial Surgery Unit of the University Hospital of Parma. Treatment of malocclusion was performed after the correction of facial mimic mobility with smile surgery. The postoperative stability and orthodontic results were good and the correction of the morphological problems related to the syndrome was very satisfactory.

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.

Reanimation surgery in patients with acquired bilateral facial palsy

Acquired bilateral facial palsy is rare and causes difficulty with speech and eating, but dynamic reanimation of the face can reduce the effect of these problems. Of 712 patients who had these procedures during our study period, two had an acquired bilateral facial paralysis. In both, reanimation was completed in a single operation using a free-functional transfer of the latissimus dorsi muscle that was coapted to the masseteric branch of the trigeminal nerve. Both patients achieved excellent non-spontaneous excursion and an improvement in function. Careful evaluation of the available donor nerves including thorough examination and electromyographic testing should always be completed before operation.

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

BACKGROUND

For the treatment of facial paralysis, functioning free muscle transplantation has become accepted standard treatment. Choice of donor nerve and number of surgery stages, however, are still matters of great debate.

METHODS

Between 2000 and 2011, 36 patients (out of 329; 11 percent) with 42 functioning free muscle transplantations were treated using spinal accessory nerve (XI)-innervated muscle for facial reanimation as a one-stage procedure. Indications included bilateral or unilateral Möbius syndrome, severe postparetic facial synkinesis, and patient preference. Postoperative smile training was required to achieve spontaneous smile. For outcome assessment, patients were evaluated using multidisciplinary methods, including objective smile excursion score (range, 0 to 4), cortical adaptation stage (range, I to V), tickle test, and subjective patient questionnaire and satisfaction score (range, 1 to 5).

RESULTS

Mean smile excursion score improved from 0.5 preoperatively to 3.4 postoperatively. Eighty-three percent of patients were able to perform independent and even spontaneous smile after 1 year of follow-up. Ninety percent of patients had a mean satisfaction score of 3.4 out of 5. However, 50 percent expressed more concern with aesthetic appearance than functional status. There was no functional morbidity of the donor shoulder in daily life.

CONCLUSIONS

The classic two-stage procedure is still the first choice for facial paralysis reconstruction. However, the effectiveness of XI-innervated free muscle for facial reanimation in a one-stage procedure has proven it to be a good alternative treatment. It has become second in popularity for facial paralysis reconstruction in the authors' center.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Treatment of severe skeletal open bite deformity in patients with Möbius syndrome: a report of 3 cases

PURPOSE

To investigate the treatment of severe skeletal open bite deformities in Möbius syndrome patients.

MATERIALS AND METHODS

Three patients aged 17 to 24 years (2 male patients and 1 female patient) with Möbius syndrome were evaluated and treated with preoperative orthodontics, orthognathic surgery, and postoperative orthodontic management. One patient was treated by bilateral V osteotomies of the mandibular body and one patient with bilateral V osteotomies of the mandibular body plus a Le Fort I osteotomy. The third patient had bilateral mandibular ramus sagittal split osteotomies in combination with maxillary osteotomies. Two of the patients had preoperative electromyographic studies on the temporalis and masseter muscles.

RESULTS

Postoperative and post-orthodontic stability was good in 2 cases, whereas a 5-mm anterior open bite developed after treatment in 1 case and additional orthodontic management was required to re-establish good occlusion. Potential to redevelop anterior open bites may likely be related to the functional deficiencies of the muscles of mastication and facial paralysis. Two patients who had electromyographic studies to evaluate muscle function showed lower-than-normal function of the temporalis and masseter muscles. Lower lip ptosis remained a significant esthetic issue in 2 of 3 patients.

CONCLUSIONS

Patients with Möbius syndrome with severe skeletal open bite deformities can be treated with combined orthodontic and orthognathic surgery; however, there is a tendency for redevelopment of an anterior open bite with the surgical and orthodontic techniques used in these cases.

Surgical management of facial nerve paralysis in the pediatric population

BACKGROUND

In the pediatric patient population, both the pathology and the surgical managements of seventh cranial nerve palsy are complicated by the small size of the patients. Adding to the technical difficulty is the relative infrequency of the diagnosis, thus making it harder to become proficient in the management of the condition. The magnitude of the functional and aesthetic deficits these children manifest is significantly troubling to both the patient and the parents, which makes immediate attention, treatment, and functional restoration essential.

METHODS

A literature search using PubMed (http://www.pubmed.org) was undertaken to identify the current state of surgical management of pediatric facial paralysis.

RESULTS

Although a multitude of techniques have been used, the ideal reconstructive procedure that addresses all of the functional and cosmetic needs of these children has yet to be described. Certainly, future research and innovative thinking will yield progressively better techniques that may, one day, emulate the native facial musculature with remarkable precision.

CONCLUSION

The necessity for surgical intervention in children with facial nerve paralysis differs depending on many factors including the acute/chronic nature of the defect as well as the extent of functional and cosmetic damage. In this article, we review the surgical procedures that have been used to treat pediatric facial nerve paralysis and provide therapeutic facial reanimation.

A single hypoglossal nerve for bilateral smile reconstruction in Möbius syndrome

Möbius syndrome is a rare congenital disorder characterized by a variety of cranial nerve defects. Although there are several variants of Möbius syndrome depending on which cranial nerves are affected, the commonest form involves facial and abducens cranial nerve paralysis. Despite several strategies for bilateral smile reconstruction that have been advocated, the condition still presents a challenge to the plastic surgeon. The most acceptable method nowadays is bilateral free neurovascularized muscle transfer. The author represents a new method of using a single hypoglossal nerve to supply both free flaps in a Möbius patient. The procedure is done on 2 stages using both latissimus dorsi muscles and a single hypoglossal nerve. The patient regained a natural symmetric smile 12 months after the first stage. Despite hemilingual atrophy, no tongue morbidity was observed. The author concludes that despite the limitation of the study, the hypoglossal nerve is a good nerve source to supply both free flaps for smile reconstruction in Möbius syndrome.

Successful salvage surgery after treatment failures with cross graft and free muscle transplant in facial reanimation

BACKGROUND

The microneurovascular transfer of a free-muscle transplant is the procedure of choice for facial animation, It is characterized by low morbidity in both adult and paediatric patients. In spite of the improvements in microsurgical techniques, failures due to absent revascularization or reinnervation of the transplanted muscle or infections causing flap necrosis are observed. We propose a second surgical procedure based on the gracilis muscle transplant reinnervated by the masseteric nerve as a solution for these cases.

METHODS

We analyzed and report on two patients treated in our department after the failure of a previous cross-facial nerve graft and free muscle transplant. They were treated with a new facial reanimation using the contralateral gracilis muscle and the masseteric nerve as the donor nerve.

RESULTS AND DISCUSSION

We did not observe any postoperative complications, and all of the flaps survived. Reinnervation and contraction of the muscle appeared 3-4 months postoperatively, with good functional and aesthetic results.

CONCLUSIONS

This technique is a one-step procedure characterized by reliable flap harvesting, low donor site morbidity and good activity of the masseteric nerve. We consider it as a good option for treatment of facial animation failures.

Reanimation of the middle and lower face in facial paralysis: review of the literature and personal approach

Facial paralysis refers to a condition in which all or portions of the facial nerve are paralysed. The facial nerve controls the muscles of facial expression, paralysis which results in a lack of facial expression which is not only an aesthetic issue, but has functional consequences as the patient cannot communicate effectively. The treatment of long-standing facial paralysis has challenged plastic surgeons for centuries, and still the ultimate goal of normality of the paralysed hemi-face with symmetry at rest as well as the generation of a spontaneous symmetrical smile with corneal protection has not yet fully been reached. Until the end of the 19th century, the treatment of this condition involved non-surgical means such as ointments, medicines and electrotherapy. With the advent and refinement of microvascular surgical techniques in the latter half of the 20th century, vascularised free muscle transfers coupled with cross-facial nerve grafts were introduced, allowing the possibility of spontaneous emotion being restored to the paralysed face became reality. The aim of this article is to revisit the surgical evolution and current options available as well as outcomes for patients suffering from facial paralysis concentrating on middle and lower face reanimation.

Facial animation in children with Moebius and Moebius-like syndromes

BACKGROUND

Moebius syndrome, a rare congenital disorder of varying severity, involves multiple cranial nerves and is characterized predominantly by bilateral or unilateral paralysis of the facial and abducens nerves. The paralysis of the VI and VII cranial nerves leads to a lack of function in the muscles they supply. Facial paralysis often causes bilabial incompetence with speech difficulties, oral incompetence, problems with eating and drinking, including pocketing of food in the cheek and dribbling, as well as severe drooling.

METHODS

In this study, we report on pediatric patients with Moebius and Moebius-like syndromes seen and treated surgically from 2003 to September 2007 at the Operative Unit of Maxillofacial Surgery, Head and Neck Department, University of Parma, Italy.

RESULTS

Twelve patients underwent microsurgical reconstruction for restoration of facial movement. The contralateral facial nerve was used as a motor donor nerve in 4 procedures, the motor nerve to the masseter muscle was used in 8 patients, and the gracilis muscle was used in all operations, with a total of 17 free-muscle transplantations. All free-muscle transplantations survived transfer, and no flap was lost. We observed a significant improvement in drooling, drinking, speech, and facial animation with a high degree of patient satisfaction.

CONCLUSIONS

The gracilis muscle free transfer is a surgical procedure well tolerated by the young patients and well accepted by their families. We consider it a safe and reliable technique for facial reanimation with good aesthetical and functional results in children with Moebius and Moebius-like syndromes.

Ectopic bone formation as a complication of surgical rehabilitation in patients with Moebius’ syndrome

PURPOSE

Treatment of facial paralysis by muscular neurotization resulted in ectopic ossification in 1 of 134 cases in this department. That patient suffering from Moebius syndrome (MS) is presented. Reviewing the literature concerning MS, Hox genes and bone morphogenetic protein dysregulation, a pathogenesis of ossification in MS is suggested.

PATIENT

The MS patient exhibited a congenital facial nerve palsy, which was treated by muscular neurotization (Lexer-Rosenthal). Because of postoperative ossification of scarred areas, osteotomy of the processus muscularis and mobilization of the masseter muscle was performed. Nevertheless, further ossification occurred at the interface between the mandible and zygoma and in two masticatory muscles. So, the construction of a neoarthrosis became necessary. Three years later, the iatrogenic bone defect had reossified despite of an active opening therapy.

CONCLUSIONS

Ectopic ossification after muscular neurotization seems to be restricted to patients with MS and is triggered by trauma. Molecular pathogenesis: facial malformations in MS are caused by disturbances in embryonic patterning. Failure in the development of the second pharyngeal arch leads to a spatial BMP-4 dysregulation responsible for ossification after wounding of muscle fascia. Therefore, surgical rehabilitation of facial function by muscular neurotization is contra indicated in MS patients.

Anesthetic implications of Möbius syndrome

Möbius syndrome is a rare disorder characterized by unilateral or bilateral facial paralysis and defective extraocular eye movements secondary to congenital paresis of the facial (VII) and abducens (VI) cranial nerves. Associated dysfunction of other cranial nerves, orofacial abnormalities, and skeletal muscle hypotonia are common accompanying features. Given the multisystem involvement of Möbius syndrome, there are several potential perioperative concerns. Of primary importance to the anesthesia provider are the propensity for postoperative respiratory failure due to several pathological mechanisms, associated orofacial abnormalities that may make routine airway management difficult, the presence of gastroesophageal reflux and other factors that increase the risk of perioperative aspiration, and associated hypotonia of the skeletal musculature. The authors present a 10-month-old infant with Möbius syndrome who required anesthetic care during a Nissen fundoplication. The potential anesthetic implications of this syndrome are discussed.