Reanimation of the paralyzed face by indirect hypoglossal-facial nerve anastomosis

Malformation of the external ear and facial paralysis caused by megatemperature hydro-aluminum

We present a case of right lateral auricle contracture malformation, auricular canal atresia, and complete facial paralysis (House-Brackmann grade VI) caused by a megatemperature hydro-aluminum injury at work. The diastrophic auricle and auricular canal atresia were reshaped. The complete facial paralysis was reanimated to House-Brackmann grade III after surgical hypoglossal-facial end-to-end anastomosis. These outcomes indicate that hypoglossal-facial end-to-end anastomosis is an effective surgical option for successful reanimation of complete facial paralysis.

Chapter 8: Current techniques and concepts in peripheral nerve repair

Despite the progress in understanding the pathophysiology of peripheral nervous system injury and regeneration, as well as advancements in microsurgical techniques, peripheral nerve injuries are still a major challenge for reconstructive surgeons. Thorough knowledge of anatomy, pathophysiology, and surgical reconstruction is a prerequisite of proper peripheral nerve injury management. This chapter reviews the currently available surgical treatment options for different types of nerve injuries in clinical conditions. In overview of direct nerve repair, various end-to-end coaptation techniques and the role of end-to-side repair for proximal nerve injuries is described. When primary repair cannot be performed without undue tension, nerve grafting or tubulization techniques are required. Current gold standard for bridging nerve gaps is nerve autografting. However, disadvantages of this approach, such as donor site morbidity and limited length of available graft material encouraged the search for alternative means of nerve gap reconstruction. Nerve allografting was introduced for repair of extensive nerve injuries. Tubulization techniques with natural or artificial conduits are applicable as an alternative for bridging short nerve defects without the morbidities associated with harvesting of autologous nerve grafts. Achieving better outcomes depends both on the advancements in microsurgical techniques and introduction of molecular biology discoveries into clinical practice. The field of peripheral nerve research is dynamically developing and concentrates on more sophisticated approaches tested at the basic science level. Future directions in peripheral nerve reconstruction including, tolerance induction and minimal immunosuppression for nerve allografting, cell based supportive therapies and bioengineering of nerve conduits are also reviewed in this chapter.

The long thoracic nerve as a donor for facial nerve reanimation procedures: cadaveric feasibility study

Object

Injury of the facial nerve with resultant facial muscle paralysis may result in other significant complications such as corneal ulceration. To the authors' knowledge, neurotization to the facial nerve using the long thoracic nerve (LTN), a nerve used previously for neurotization to other branches of the brachial plexus, has not been explored previously.

Methods

In an attempt to identify an additional nerve donor candidate for facial nerve neurotization, 8 adult human cadavers (16 sides) underwent dissection of the LTN, which was passed deep to the clavicle and axillary neurovascular bundle. The facial nerve was localized from the stylomastoid foramen onto the face, and the distal cut end of the previously dissected LTN was tunneled to this location. Measurements were made of the length and diameter of the LTN. Long thoracic nerve innervation to the first and second digitations of the serratus anterior was maintained on all sides.

Results

All specimens were found to have an LTN with more than enough length to be tunneled superiorly, tension-free to the extracranial facial nerve. Connections remained tensionless with left and right head rotation of up to 45°. The mean length of this part of the LTN was 18 cm with a range of 15–22 cm. The overall mean diameter of this nerve was 2.5 mm. No evidence of injury to the surrounding neurovascular structures was identified on gross examination.

Conclusions

To the authors' knowledge, the LTN has not been previously examined as a donor nerve for facial nerve reanimation procedures. Based on the results of this cadaveric study, the use of the LTN may be considered for such surgical maneuvers.

Impact of different types of facial nerve reconstruction on the recovery of motor function: an experimental study in adult rats

OBJECTIVE

Poor functional recovery after facial nerve reconstruction is characterized by mass movements and synkinesis. Major reasons are axonal sprouting from the regenerating axons leading to misdirected reinnervation and hyperinnervation as well as polyinnervation of the mimic muscle end plates. We analyzed whether or not the type of nerve reconstruction influenced these pathological phenomena.

METHODS

The experiments were performed on 48 adult rats divided into four groups. One group served as an intact control and the experimental groups were subjected to facial-facial nerve repair (FFN), facial nerve interpositional grafting, and hypoglossal-facial nerve repair (HFN), with 12 subjects in each group. Two months later, functional recovery was measured by biometrical motion analysis of whisking. Retrograde fluorescence labeling of the brainstem motoneurons was used to quantify the degree of collateral axonal branching at the lesion site. Fluorescence histochemistry of sections through the levator labii superioris muscle was performed to quantify the degree of polyinnervation after surgery.

RESULTS

The type of nerve reconstruction significantly influenced the regeneration. The whisking amplitude did not recover completely regardless of the type of reconstruction. The angular velocity and angular acceleration of the vibrissal hairs showed a full recovery after facial nerve interpositional grafting and HFN, whereas these parameters remained decreased after FFN. Significantly less collateral branching and polyinnervation of the end plates were determined after grafting and HFN than after FFN.

CONCLUSION

No type of immediate facial nerve reconstruction results in a full recovery in the rat. However, the morphological and functional recovery was significantly better after grafting and HFN than after FFN.

Suprascapular nerve as a donor for extracranial facial nerve reanimation procedures: a cadaveric feasibility study

OBJECTIVES

Facial nerve injury with resultant facial muscle paralysis is disfiguring and disabling. To the authors' knowledge, neurotization of the facial nerve using a branch of the brachial plexus has not been previously performed.

METHODS

In an attempt to identify an additional nerve donor candidate for facial nerve neurotization, 5 fresh adult human cadavers (10 sides) underwent dissection of the suprascapular nerve distal to the suprascapular notch where it was transected. The facial nerve was localized from the stylomastoid foramen onto the face, and the cut end of the suprascapular nerve was tunneled to this location. Measurements were made of the length and diameter of the supra-scapular nerve. In 2 of these specimens prior to transection of the nerve, a nerve-splitting technique was used.

RESULTS

All specimens were found to have a suprascapular nerve with enough length to be tunneled, tension free, superiorly to the extracranial facial nerve. Connections remained tensionless with left and right head rotation of up to 45 degrees . The mean length of this part of the suprascapular nerve was 12.5 cm (range 11.5-14 cm). The mean diameter of this nerve was 3 mm. A nerve-splitting technique was also easily performed. No gross evidence of injury to surrounding neurovascular structures was identified.

CONCLUSIONS

To the authors' knowledge, the suprascapular nerve has not been previously explored as a donor nerve for facial nerve reanimation procedures. Based on the results of this cadaveric study, the authors believe that use of the suprascapular nerve may be considered for surgical maneuvers.

Surgical results of the Hypoglossal-Facial nerve Jump Graft technique

BACKGROUND

The Hypoglossal-Facial nerve crossover has appeared as a surgical option for those scenarios where the facial nerve is injured in its intracranial course, but the conventional technique unequivocally leads to twelfth cranial nerve deficit. In recent years a number of different surgical approaches have been introduced with a view to avoiding the complete section of the hypoglossal nerve, such as the Jump Graft technique. This paper aims to present the results of the Hypoglossal-Facial nerve Jump Graft technique in relation to facial musculature reanimation capability and hemitongue function preservation.

METHODS

A retrospective analysis of the records of eight patients submitted to Hypoglossal-Facial nerve Jump Graft technique was performed. The surgical approach was characterised by the interposition of a short graft sutured to the distal stump of the transected facial nerve and sutured end-to-side to the hypoglossi, with cutting of only a third of the diameter of the latter.

FINDINGS

The facial nerve injuries were secondary to temporal bone trauma in five cases and to cerebellopontine angle tumour surgery in three. Grafts were harvested from the greater auricular nerve in six patients and from the sural nerve in two. The results of facial reanimation demonstrated facial symmetry and improvement in the facial tone in all cases, and classified as House-Brackmann grade IV in three (37.5%) and grade III in five (62.5%) patients. There was no incidence of definitive hemitongue atrophy and no patient complaint of swallowing or speech difficulty.

CONCLUSIONS

The modification of the conventional technique of Hypoglossal-Facial nerve anastomosis by means of sectioning one third of the hypoglossal nerve area does not lead to dysfunction of this nerve and the surgical results in terms of facial reanimation are satisfactory.

Facial reanimation by means of the hypoglossal nerve: anatomic comparison of different techniques

OBJECTIVE

The goal of this study was to determine the various anatomical and surgical relationships between the facial and hypoglossal nerves to define the required length of each for a nerve transfer, either by means of a classical hypoglossal-facial nerve anastomosis or combined with any of its variants developed to reduce tongue morbidities.

METHODS

Five adult cadaver heads were bilaterally dissected in the parotid and submaxillary regions. Two clinical cases are described for illustration.

RESULTS

The prebifurcation extracranial facial nerve is found 4.82 +/- 0.88 mm from the external auditory meatus, 5.31 +/- 1.50 mm from the mastoid tip, 15.65 +/- 0.85 mm from the lateral end of C1, 17.19 +/- 1.64 mm from the border of the mandible condyle, and 4.86 +/- 1.29 mm from the digastric muscle. The average lengths of the mastoid segment of the facial nerve and the prebifurcation extracranial facial nerve are 16.35 +/- 1.21 mm and 18.93 +/- 1.41 mm, respectively. The average distance from the bifurcation of the facial nerve to the hypoglossal nerve turn is 31.56 +/- 2.53 mm. For a direct hypoglossal-facial nerve anastomosis, a length of approximately 19 mm of the hypoglossal nerve is required. For the interposition nerve graft technique, a 35 mm-long graft is required. For the technique using a longitudinally dissected hypoglossal nerve, an average length of 31.56 mm is required. Exposure of the facial nerve within the mastoid process drilling technique requires 16.35 mm of drilling.

CONCLUSION

This study attempts to establish the exact graft, dissection within the hypoglossal nerve, and mastoid drilling requirements for hypoglossal to facial nerve transfer.

Manual stimulation of facial muscles improves functional recovery after hypoglossal–facial anastomosis and interpositional nerve grafting of the facial nerve in adult rats

The facial nerve in humans is often prone to injuries requiring surgical intervention. In the best case, nerve reconstruction is achieved by a facial-facial anastomosis (FFA), i.e. suture of the proximal and distal stumps of the severed facial nerve. Although a method of choice, FFA rarely leads to a satisfactory functional recovery. We have recently devised and validated, in an established experimental paradigm in rats, a novel strategy to improve the outcome of FFA by daily manual stimulation (MS) of facial muscles. This treatment results in full recovery of facial movements (whisking) and is achieved by reducing the proportion of functionally detrimental poly-innervated motor end-plates. Here we asked whether MS could also be beneficial after two other commonly used surgical methods of clinical facial nerve reconstruction namely hypoglossal-facial anastomosis (HFA) and interpositional nerve grafting (IPNG) which, however, seem to have a poorer outcome compared to FFA. Compared to FFA, daily MS for 2 months after HFA and IPGN did not completely restore function but, nevertheless, significantly improved the amplitude of whisker movements by 50% compared with untreated animals. Functional improvement was associated with a reduction in the proportion of polyinnervated end-plates. MS did not reduce the extent of axonal branching at the lesion site nor the subsequent misdirected axonal regrowth to inappropriate targets. Our data show that a simple approach leading to improved quality of muscle fiber reinnervation is functionally beneficial after different types of clinically relevant surgical interventions.

[Rehabilitation options for lesions of the facial nerve]

Patients with permanent facial palsies cannot hide their conditions. As a consequence, these patients suffer from massive psychological stress. To achieve satisfactory reconstruction of mimic function, experience with a variety of surgical techniques and adjuvant nonsurgical treatments is necessary. This report provides information on the present repertoire of surgical and conservative options, emphasizing their fields of indications, limitations, and possible combinations.

Hypoglossal-facial anastomosis

The aim of this paper was to report on further experience with a new technique for reanimation of the facial nerve. This procedure allows a straight end-to-side hypoglossal–facial anastomosis without interruption of the 12th cranial nerve or the need for graft interposition. It is technically demanding and time consuming but offers an effective, reliable, and extraordinarily quick means of reinnervating the facial muscles, including the orbicularis oculi muscle, thus avoiding the need for a gold weight in the eyelid or a fascial sling.

Intraparotid facial nerve schwannoma. What to do?

An intraparotid facial nerve schwannoma is often not recognised in pre-treatment work-up and frequently results in subsequent significant postoperative morbidity. We have evaluated the literature regarding pre-treatment work-up and facial nerve function outcome. Two of our own cases are presented. A minority of the intraparotid schwannomas can be removed by resection while preserving facial nerve integrity and function. In the event of preoperative facial nerve dysfunction, tumour resection and subsequent nerve repair should be considered. If resection of an intraparotid facial nerve schwannoma cannot be performed with preservation of facial nerve integrity and function, a wait-and-see policy seems justified due to the indolent behaviour of the tumour and moderate results of facial nerve reconstruction.

Advances in facial reanimation

PURPOSE OF REVIEW

Facial paralysis often has a significant emotional impact on patients. Along with the myriad of new surgical techniques in managing facial paralysis comes the challenge of selecting the most effective procedure for the patient. This review delineates common surgical techniques and reviews state-of-the-art techniques.

RECENT FINDINGS

The options for dynamic reanimation of the paralyzed face must be examined in the context of several patient factors, including age, overall health, and patient desires. The best functional results are obtained with direct facial nerve anastomosis and interpositional nerve grafts. In long-standing facial paralysis, temporalis muscle transfer gives a dependable and quick result. Microvascular free tissue transfer is a reliable technique with reanimation potential whose results continue to improve as microsurgical expertise increases. Postoperative results can be improved with ancillary soft tissue procedures, as well as botulinum toxin.

SUMMARY

The paper provides an overview of recent advances in facial reanimation, including preoperative assessment, surgical reconstruction options, and postoperative management.

Side-to-end hypoglossal-facial anastomosis via transposition of the intratemporal facial nerve

The technique of facial nerve repair with side-to-end hypoglossal-facial anastomosis is presented and evaluated in five patients who were operated on for facial nerve paralysis after acoustic schwannoma surgery, or had cranial base trauma. The end-to-end hypoglossal-facial anastomosis is accompanied by hemilingual paralysis, with difficulty in swallowing, chewing and speaking. In this new technique, the facial nerve is mobilised in the temporal bone, transected at the second genu and transposed to the hypoglossal nerve where a tensionless side-to-end anastomosis is performed. The hypoglossal nerve is transected in oblique fashion to about one third of its circumference. We were able to achieve a tensionless anastomosis in all patients. The idea is to bring about re-innervation of the previously denervated tissue via a collateral sprouting of axons of the donor nerve through the site of coaptation without sacrificing the innervation of the donor nerve's original targets. With side-to-end hypoglossal-facial anastomosis, two patients attained a House- Brackmann grade of III (one of them with independent movement of eyelids and mouth); one achieved grade IV, another grade V and grade VI. No patient had hemilingual atrophy nor any problems associated with swallowing or chewing.

Postoperative functional evaluation of different reanimation techniques for facial nerve repair

BACKGROUND

The facial nerve function after facial-facial nerve anastomosis, grafting, hypoglossal-facial nerve anastomosis, hypoglossal-facial interpositional jump nerve anastomosis, or a combined approach was analyzed.

METHODS

Facial function was assessed after operation using a 7-point visual analog scale (VAS) and by electromyography (EMG) in 53 patients. The final result was judged by May's facial nerve grading system.

RESULTS

Voluntary EMG activity occurred on average 4.52 +/- 1.31 months after operation. Initial facial movements were visible after 5.41 +/- 1.80 months. Facial function related to the VAS finally reached 44% of normal value. The result was judged May's grade I in 13%, grade II in 34%, grade III in 28%, and grade IV in 25% of patients. A significant difference in outcome between different reconstruction types was not seen. Age over 60 years was related to worse outcome.

CONCLUSIONS

A correct selection of the best method in the individual situation presumed, all analyzed facial reanimation techniques seem to lead nearly similar and satisfactory results.

[Paralyzed face. Ansa-cervicalis-nervi-hypoglossi]

INTRODUCTION

For 100 years hypoglossal-facial nerve anastomosis (HFA) has been a common surgical procedure for reanimation of paralyzed mimic muscles of the face after axotomy of the facial nerve. However, the denervation and subsequent scarred degeneration of the target muscles of the hypoglossal nerve often results in unfavorable late effects for speech and swallowing. Therefore, the ansa cervicalis nervi hypoglossi-facial nerve anastomosis (ACHFA) can be an alternative to avoid such late effects. As a branch of the hypoglossal nerve the ansa cervicalis innervates the infrahyoidal muscles. Neck dissection surgery proved that resection of the ansa cervicalis causes no side effects for swallowing because of several nerve anastomoses to the cervical plexus.

PATIENTS AND METHOD

We compared our clinical results of eight cases following a delayed ACHFA with our own experiences after HFA and results from the literature.

RESULTS

We found a reanimation rate lower than usually seen after HFA only in the target muscles of the forehead. This may be caused by a reduced neuronal plasticity of the ansa cervicalis. However, in the target muscles of the other two facial nerve branches we observed the same good results one would expect after HFA. There were no late side effects for swallowing and speech though.

The facial nerve in the presence of a head and neck neoplasm: assessment and outcome after surgical management

PURPOSE OF REVIEW

The face is the mirror of personality. Facial expression is the most important part of verbal and nonverbal communication. Patients with head and neck neoplasm and facial palsy are more stigmatized by the latter than by the tumor itself. Facial nerve reconstruction in such a patient is a great challenge. This review gives an overview of the assessment of facial palsy, surgical reconstruction, and postoperative treatment.

RECENT FINDINGS

MRI, CT, and electromyography are indispensable tools in the assessment of preoperative facial palsy in patients with head and neck neoplasm. When part of the facial nerve has to be sacrificed during surgery, the best functional results are achieved with direct facial nerve suture, interposition graft, or by a hypoglossal-facial nerve interposition jump anastomosis. The latter is the best choice when the reanimation is planned between 6 months and 2 years after tumor surgery. In any case, the eye is best rehabilitated with upper lid loading. Temporalis muscle transposition gives fast and good results for the restoration of the corner of the mouth after radical surgery. Reanimation by free muscle transfer for head and neck cancer patients is rarely indicated. Botulinum toxin treatment is an excellent postoperative aid for refining the result; the optimal modality of postoperative physiotherapy is still unclear.

SUMMARY

Surgical reanimation of the face in head and neck patients has reached a high standard. Strategies to decrease misdirected reinnervation after nerve suture have to be established in clinical practice for further improvement of facial rehabilitation.

Was Thomasz Drobnik really the first to operate on the facial nerve?

Thomasz Drobnik is considered to have been the first to operate on the facial nerve. The original report of this operation has unfortunately never been found. Because Drobnik's procedure has generally been considered to be the first documented facial nerve repair in history, it is interesting to explore Drobnik's background and the veracity of this claim. Three sources were studied: (1) literature on facial nerve repair; (2) L'état actuel de la chirurgie nerveuse, the oldest known reference to Drobnik's operation; and (3) some biographies of Drobnik. It is concluded that Thomasz Drobnik was not the first to operate on the facial nerve in 1879. Instead, the first was Sir Charles Balance, of London, England, in 1895.

The surgical management of facial nerve injury

Treatment of facial nerve injuries depends upon a detailed understanding of its anatomic course, accurate clinical examination, and timely and appropriate diagnostic studies. Reconstruction depends upon the extent of injury, the availability of the proximal stump. and the time since injury and duration of muscle denervation. Although no alternative is perfect, these techniques, in combination with static and ancillary procedures. can protect the eye, prevent drooling, restore the smile, and improve facial symmetry. New techniques (including single-stage free tissue transfers and bioengineered nerve grafts), further research on the characteristics of the facial musculature, and methods of preserving the neuromuscular junction will undoubtedly manifest themselves as further refinements of established surgical techniques.