The facial nerve. Current trends in diagnosis, treatment, and rehabilitation

Facial paralysis is a potentially devastating disorder with numerous implications. Multiple entities must be considered in its etiology, and recent advances in microbiology, radiographic imaging, electrodiagnostic testing, and microsurgery have provided great insight into the pathophysiology, diagnosis, treatment, and rehabilitation of the facial nerve. Recent DNA PCR testing has shed new insight into the potential cause for Bell's palsy. This article focuses on the evaluation, differential diagnosis, medical treatment, and rehabilitation of facial nerve pathology with primary emphasis on facial paralysis. Surgical management is also discussed, including reanimation of the paralyzed face.     

Total facial nerve decompression: technique to avoid complications

Exposure of the facial nerve from the brainstem to the parotid can be accomplished without injury to the nerve, tympanic membrane, external auditory canal, ossicular chain, inner ear or structures within the cerebello-pontine angle. The procedure has reliably provided good results for patients who have had the proper indications with facial paralysis from Bell's palsy, herpes zoster oticus, infection, hemi-facial spasm, temporal bone fracture and tumors. The current technique for exposure through the mastoid, middle cranial fossa and retrolabyrinthine combined approaches are described. This technique, properly performed, is a valuable treatment for facial nerve lesions.     

Botulinum toxin injection effective for post-peripheral facial nerve palsy synkinesis]

Facial synkinesis is an involuntary activation of muscles innervated by the zygomatic or mandibular branch of the facial nerve in conjunction with voluntary activation of the other branch. It appears frequently after recovery from peripheral facial nerve paralysis. We report 10 patients with facial synkinesis following Bell's palsy with a mean duration of synkinesis of 7 +/- 4 years before treatment with periorbital injections of Botulinum toxin type A. 9 had marked subjective and objective improvement starting a few days after injection and lasting 4-9 months. The results suggest a useful treatment option for post-Bell's palsy facial synkinesis with Botulinum toxin type A.     

Facial palsy following trauma to the external ear: 3 case reports

We report two children and a young adult who developed unilateral facial palsy shortly after injury to the external ear. In two instances the paralysis followed a prominent ear correction and in the other a laceration to the concha. The trauma-triggered facial palsy was most likely idiopathic although the anatomy of the facial nerve near the ear leads one to speculate on a possible pathway of a virally induced palsy (Bell's palsy). Each patient recovered over a period of 6 months.     

Electroconvulsive therapy in therapy refractory depression in the elderly. Report of experiences

The aetiology of idiopathic facial nerve palsy (Bell's palsy) and sudden deafness are not known, although viruses have been suspected as a cause of them. We investigated the relationship between Bell's palsy or sudden deafness, and reactivation of cytomegalovirus, human herpesvirus 6 (HHV-6) and 7 (HHV-7). Paired sera were collected from 22 patients with Bell's palsy and 24 patients with sudden deafness. IgG antibody titres to HHV-7 were increased in one patient with Bell's palsy. IgG antibody titres to HHV-6 were increased in one patient with Bell's palsy and two with sudden deafness. IgG antibody titres to cytomegalovirus were increased in one patient with sudden deafness. Titres of the three viral antibodies were not increased simultaneously in any patients. These viruses may contribute to the development of Bell's palsy or sudden deafness in some cases. It is, however, unlikely that these viruses are the main cause of Bell's palsy and sudden deafness in the majority of patients.     

Quantitative analyses for facial nerve MR imaging

It is clear, from our clinical experience, that the facial nerve in patients with facial palsy is enhanced on magnetic resonance (MR) imaging after intravenous administration of gadolinium diethylenetriamine. However, some problems with clinical reliability persist. There have been reports that normal facial nerves often show enhancement on MR imaging. We also question whether there are any differences in the degree of enhancement between Bell's palsy and Ramsay Hunt syndrome. To solve these problems, analyses were conducted using a personal computer by means of digital image-processing to measure the gray scale levels of enhanced facial nerves on MR imaging films. Seventeen cases of Bell's palsy, eight cases of Ramsay Hunt syndrome and fourteen normal subjects whose facial nerves showed enhancement on MR imaging were selected for the analyses. The concept of a facial nerve/whole image ratio (F/W ratio), analyzing the degree of enhancement of the facial nerve quantitatively, is introduced in this paper. The F/W ratio is the ratio of the gray scale level of the facial nerve region to the highest gray scale level in the skull at the MR imaging film. When the F/W ratios of these subjects were analyzed, no significant differences were found between Bell's Palsy and Ramsay Hunt syndrome in the degree of enhancement; facial palsy cases showed quantitatively larger F/W ratios than normal subjects.     

Human herpesvirus-6 antibodies in idiopathic facial nerve palsy and sudden deafness

Human herpesvirus-6 (HHV-6) is the causative agent for exanthem subitum. This study investigated the relationship between idiopathic facial nerve palsy (Bell's palsy), sudden deafness and HHV-6 infection. Both Bell's palsy and sudden deafness are syndromes which causes are unknown. Both of them are suspected viral infection as causative agents. Paired sera from 22 patients of Bell's palsy and 39 patients of sudden deafness were examined for reactivity to HHV-6 by the indirect immunofluorescence test. On a case of Bell's palsy and two cases of sudden deafness each of the HHV-6 antibody titers was increased.     

Gd-DPTA enhanced MRI in Bell's palsy and herpes zoster oticus: an overview and implications for future studies

Magnetic resonance imaging (MRI) is a new and important tool for use in diagnosing and investigating diseases affecting the facial nerve. In recent gadolinium-DTPA enhanced MRI (Gd-MRI) studies it has unequivocally been demonstrated that ipsilateral facial nerve contrast enhancement, predominantly in the meatal portion, is present in both Bell's palsy and herpes zoster oticus. In this overview, the results of MRI studies performed on patients with acute peripheral facial palsy, especially Bell's palsy and herpes zoster oticus, are discussed. The Gd-MRI pattern in Bell's palsy is very similar to that seen in herpes zoster oticus, and the findings reported so far support the theory that an inflammation may be the cause of the nerve injury in both cases. So far, however, Gd-MRI has not been helpful in evaluating the severity and/or prognosis of the facial palsy. Further studies employing improved techniques, including three-dimensional fast (or turbo) spin echo (3DFSE) MRI with heavily T2-weighted sections and high resolution three-dimensional Fourier transform (3DFT) MRI, need to be conducted in order to determine whether it is possible to follow the course of the disease and whether MRI and/or Gd-MRI are useful prognostic tools in the early stages of palsy.     

An assessment of physical and psychological stress of patients with facial paralysis

The purpose of this study was to determine if there is a relationship between the appearance of facial paralysis and physical or psychological stress. Subjects were 55 patients (23 men, 32 women) with facial paralysis (32 with Bell's palsy, 23 with Ramsay Hunt syndrome) who visited the Department of Otolaryngology, Nihon University Itabashi Hospital, from August 1994 to March 1996. At the time of the initial visit, patients were asked if they had any physical or psychological stress one week before the occurrence of facial paralysis. The degree of psychological stress was rated by Niina's Psychological Stress Response Scale 50 Items Revised (PSRS-50R). Answers were obtained from 52 of the 55 subjects. Forty patients (76.9%) reported that they had felt physically fatigued, suggesting some type of relationship between the occurrence of facial paralysis and physical stress. Twenty-seven patients (51.9%) reported the existence of psychological stress. However, the evaluation of psychological stress by PSRS-50R did not reveal a high level of psychological stress in any patient, indicating lack of a strong relationship between the occurrence of facial paralysis and psychological stress. Stepwise regression analyses were made to study the relationship between the degree of paralysis at the time of the initial visit and factors which affect the prognosis of the paralysis. Those patients who reported physical fatigue before the appearance of facial paralysis had more abnormal values on the nerve excitability test than those who did not report such fatigue.     

Bell's palsy (prevention and treatment)

The effectiveness of a variety of the most popular methods used for treatment Bell's paralysis is analyzed on a great number (1168 patients) of cases. It has been found that the results of the treatment are predetermined primarily by the gravity of the facial nerve affection. No convincing dependence of the treatment effect on the disease etiology was noted, except cases of Bell's paralysis of vascular etiology, the outcome of which was worse. A less favourable outcome was also observed in patients over 60 years of age and in cases of paralysis relapses. Of the methods of treating Bell's paralysis tested by the authors it was early use of perineural injections of hydrocortisone and novocaine in combination with the traditional methods (etiotropic, resorptive, and restorative means, electrotherapy, exercises) that proved to be the most efficacious. On the basis of the follow-up study of 676 patients recommendations on the treatment of residual phenomena of Bell's paralysis and on preventing the latter's relapses are given.     

A comparison of transcranial magnetic stimulation with electroneuronography as a predictive test in patients with Bell's palsy

The aim of this study was to examine the neuronographic findings of electrical and transcranial magnetic stimulation of the facial nerve and to compare their ability to predict clinical recovery from idiopathic facial nerve palsy (Bell's palsy). Eighty-six patients were examined clinically and neurophysiologically immediately on presentation to Tampere University Hospital. Electroneuronography (ENoG) and transcranial magnetic stimulation (TMS) were performed 1-6 times for each patient. The time interval between each examination varied from 2 to 7 days. Seventy-eight patients were followed for a median period of 13 months after the onset of palsy. Facial nerve function was graded according to the House-Brackmann grading system. Relative amplitude differences of ENoG and TMS during the acute phase were then correlated with clinical outcome. Statistical analysis of the results showed that a TMS response elicitable during the first 5 days of the palsy was correlatable with a good prognosis. ENoG results correlated with clinical outcome at a later time from onset of symptoms. TMS was well tolerated and no adverse effects were seen. These results indicate that TMS is a useful method for the early prediction of outcome in patients with Bell's palsy.     

Cardiomyopathy due to a pheochromocytoma. A reversible entity

Bilateral facial nerve palsy is relatively uncommon and may occur in association with a variety of neurological, infectious, neoplastic or degenerative disorders. Presentation is made of 4 cases of bilateral facial diplegia due to a refractory anemia with excess of blasts, a Lyme disease and a tuberculoid leprosy. In one of these patients the cause of bilateral seventh-nerve palsy was unknown (Bell's palsy). Facial palsy returned to normal after treatment with steroids in 3 patients. The patient with myelodysplastic syndrome did not show any improvement and died 6 months after diagnosis.     

Hemifacial spasm caused by a hemangioma at the geniculate ganglion: case report

OBJECTIVE AND IMPORTANCE: Hemifacial spasm is rarely caused by facial nerve lesions in the temporal bone. Intratemporal facial nerve hemangiomas may initially present as facial spasm. CLINICAL PRESENTATION: A 30-year-old woman developed right hemifacial spasm. Physicians observed slight weakness on the right side of her face, in addition to the hemifacial spasm, but routine radiological examinations did not detect any abnormal findings along the course of the facial nerve. Although the patient underwent neurovascular decompression, the spasm persisted postoperatively. Two years after surgery, the right facial palsy progressed. Concurrently, the hemifacial spasm diminished. High-resolution computed tomography demonstrated a small mass lesion expanding the cortex of the right petrosal bone involving the geniculate ganglion of the facial nerve. INTERVENTION: The patient underwent a second craniotomy through a subtemporal extradural route, and the tumor was completely removed. A pathological examination demonstrated a cavernous hemangioma. CONCLUSION: Routine radiological examinations may fail to detect small intratemporal facial nerve hemangiomas, particularly at the geniculate ganglion. Therefore, when physicians encounter atypical facial spasm, the intratemporal portion of the facial nerve should be carefully examined using high-resolution computed tomography.     

Transverse and T fractures with fracture of the posterior wall of the acetabulum. Results of orthopedic and surgical treatment. Apropos of 52 cases

A patient developed delayed facial nerve palsy at the level of House-Brackmann grade I to grade III 10 days after vestibular schwannoma surgery by the suboccipital transmeatal approach. The palsy had completely recovered after one month. Immunological study showed reactivation of herpes simplex and magnetic resonance (MR) imaging demonstrated an abnormal enhancement pattern of the facial nerve; intense enhancement of the distal intracanalicular segment and labyrinthine segment, similar to the MR findings for Bell's palsy. A prospective control study on the enhancement pattern of the functionally preserved facial nerve after vestibular schwannoma surgery in six cases showed a similar pattern to that of the normal facial nerve. Based on these findings, we propose the hypothesis that herpes simplex reactivation is an underlying cause of delayed facial palsy after vestibular schwannoma surgery.     

A case of mediastinal tuberculous lymphadenitis with tracheal stenosis

The extracellular fluid pathway in the facial nerve and the diffusion of a tracer from the facial nerve to other cranial nerves was examined in the rabbit. Sodium fluorescein solution was injected into either the facial nerve fascicles or the epineurial connective tissue as a tracer at the stylomastoid foramen and then localized by fluorescence microscopy. In the facial nerve, fluorescence was observed in the endoneurium and external nerve sheath (epineurium and perineurium) through the geniculate ganglion following injection into the nerve fascicles. The vestibular, trigeminal, and glossopharyngeal ganglia also showed fluorescence on the injection side in ganglion cells and intercellular connective tissues. The results suggested that the endoneurial connective tissue constitutes a diffusion pathway inside the facial nerve fascicles and that the extracellular fluid pathway from the facial nerve to these cranial ganglia may be related to the neural spread of inflammation or neoplastic metastasis.     

Thoughts on carcinogenic pollution caused by ionizing radiation]

The lacrimal secretion in 99 healthy individuals has been measured by Schirmer's method. The established statistical limits of normal lacrimal secretion were tested in 18 patients submitted to geniculate ganglionectomy because of petrosal neuralgia, in 15 patients with traumatic, in 17 patients with idiopathic, and in 10 patients with herpetic facial palsy. A significant bilateral reduction of lacrimation was found to be as indicative for a unilateral interruption of the parasympathetic iaring. Abnormal unilateral and bilateral values of lacrimation were present in 93% of the traumatic, in 53% of the idiopathic, and in 60% of the herpetic facial palsies respectively. There is evidence that a significantly disturbed lacrimal flow has not only topographic, but also prognostic value in facial nerve palsy.     

Facial palsy in Kawasaki syndrome

Facial nerve palsy, a very rare complication of Kawasaki syndrome, has been reported in only 25 patients. We treated a 12-week-old boy with bilateral coronary artery aneurysms due to Kawasaki syndrome who developed marked unilateral peripheral facial nerve palsy on day 36 of illness. None of the 25 previously reported patients with this complication were treated with immunoglobulin; they required 7 to 90 days to recover. In our patient, treatment with this agent was associated with complete resolution of facial nerve palsy within 36 hours. Review of prior cases demonstrates that children with Kawasaki-associated facial nerve palsy have more than twice the risk for coronary artery aneurysm (52% vs <25%) as that of children who do not develop this neurological complication. Unexplained facial nerve paralysis in young children with a prolonged febrile illness should provoke consideration of Kawasaki syndrome and of echocardiography to exclude coronary artery aneurysms. Although facial palsy appears likely to resolve in all patients that survive the acute phase of Kawasaki syndrome, treatment with intravenous immunoglobulin appears to considerably shorten the time to full recovery and provides an important clue to the mechanisms of neurological injury in this illness.     

Clusters of Bell's palsy

The idiopathic facial paralysis or Bell's palsy installs abruptly or within a few hours, without any apparent cause. It corresponds to approximately 75% of all peripheral facial palsies. Three theories try to explain its pathogenecity: vascular-ischemic, viral and auto-immune. We reviewed the records of the EMG Sector, Hospital do Servidor Público Estadual (S?o Paulo, Brazil), from 1985 to 1995 and found 239 cases of Bell's palsy. Data were analysed according to age, gender, seasonal distribution of cases. There was a predominance of cases in the 31-60 age bracket (40.59%). The female gender was responsible to 70.71% of cases. There was a predominance of cases in winter (31.38%) and autumn (30.13%), which was statistically significant. These findings let us to suppose that Bell's palsy predominates in females, in 41-60 years age bracket, and occurs predominantly in cold months. There are groups of clusters throughout temporal distribution of cases and cases are dependent on one each other or on factors affecting them all, which reinforces the infectious hypothesis (there is a rise in the incidence of viral upper respiratory tract infection during cold months).     

Diagnostic importance of electrophysiologic tests in Bell's palsy: report on a longterm follow-up study in 100 cases (author's transl)

The present study is based upon the results of repeated electrodiagnostic tests carried out in a series of 100 cases of Bell's palsy (Determination of Rheobase and Chronaxy). The first symptoms of denervation can be observed during the second week after the onset of the paralysis. This seems to be the critical period in which the ultimate consequences of the lesion are determined: partial or total recovery or complete irreversible denervation. In cases showing a rapid increase of chronaxy during the 2nd week, prognosis is rather poor because a difference of 240% between the affected and the normal side indicates a progressive denervation. Cases in which the difference of chronaxy values during the 2nd week is increased upto 240% (i.e. partial denervation) recover incompletely in 15% of the cases. Estimation of prognosis in Bell's palsy and timing of a facial nerve decompression must be based on reliable facts, such as the results of repeated electrodiagnostic tests (modified measurement of Rheobase and Chronaxy) carried out at least every secont but preferably every day during the first 3 weeks after the onset of the paresis.     

Prediction of prognosis in peripheral facial nerve paralysis using submandibular gland scintigraphy

In this study, we evaluated the ability of submandibular gland scintigraphy to predict the prognosis of peripheral facial nerve paralysis. METHODS: Submandibular gland scintigraphy was performed in 78 patients with acute peripheral facial nerve paralysis. After injection of 180-370 MBq [99mTc]pertechnetate, serial 1-min images were acquired for 25 min. At 15 min after injection of radionuclide, ascorbic acid was administered intraorally to stimulate salivary secretion. Regions of interest were set manually on both submandibular glands, and time-activity curves were generated. The ratios of peak count density (PCR) and washout (WR) of the affected side to the normal side were calculated. Parameters of > or = 0.8 suggested normal affected submandibular function and indicated a good prognosis. RESULTS: Complete recovery of facial nerve paralysis was observed in 52 of 78 patients. The sensitivity, specificity and accuracy of PCR for a good prognosis were 79%, 50% and 69%, and those of WR were 85%, 77% and 82%, respectively. Positive and negative predictive values for a good prognosis were 76% and 54% in PCR and 88% and 71% in WR, respectively. When WR obtained within 14 days of the onset was used, positive and negative predictive values for a good prognosis were 94% and 73%, respectively. None of the eight patients who had values of <0.8 for both parameters within 14 days of the onset recovered completely. CONCLUSION: Submandibular gland scintigraphy can serve as a reliable indicator to predict the prognosis of acute peripheral facial nerve paralysis in its early symptomatic period.