Prediction of facial nerve displacement in extra large vestibular schwannoma

The primary objective in the surgery of extra large vestibular schwannoma is the total removal of the tumour mass while preserving the facial nerve. Preservation of the facial nerve in extra large tumours is reported as being notoriously difficult in the majority of cases. This study was undertaken to evaluate the accuracy in predicting displacement of the facial nerve by preoperative radiological imaging studies in 19 cases of extra large vestibular schwannoma. The direction of displacement of the facial nerve was predicted with preoperative axial and coronal MRI scans and verified intraoperatively. We achieved total removal of tumours in 84.2%, facial nerve displacement was predicted in 80% and we accomplished anatomical preservation in 80%. Prediction of displacement was difficult in tumours with little or no intracanalicular components or with severe bony destruction of the internal acoustic meatus. The preoperative prediction of facial nerve displacement in extra large tumours allows safe internal decompression of the tumour and careful dissection near the predicted area of the facial nerve during the operation. Consequently, a high rate of anatomical preservation of the facial nerve can be achieved.     

Parotidectomy in childhood--with a review of the literature

Parotid tumours in childhood are rare. Four patients under 16 years old having parotidectomy are described and the literature is reviewed. The presentation, pathology and prognosis of parotid tumours in childhood is different to that seen in adults. Half of the parotid tumours in childhood are malignant but most are of low grade. Rapid growth, if present, may be the only clue of malignancy and facial nerve palsy or cervical node metastasis have rarely been described. Adequate surgical excision with facial nerve preservation is the treatment of choice and radical neck dissection is rarely necessary. Radiotherapy should be avoided and the prognosis is very favourable. It is difficult to differentiate clinically between benign and low-grade malignant tumours and because of the high incidence of malignancy, all parotid tumours in childhood should be suspected of being malignant until proven otherwise.     

Extensive facial nerve tumor with atypical histology: case report

Primary facial nerve tumours are uncommon; most are benign schwannomas. Rare cases of malignant schwannomas and cellular schwannomas have been reported. The report describes a multicentric facial nerve tumor that did not fit well into any of these histopathologic categories. The tumor was removed in two stages and the patient has no clinical or radiographic evidence of recurrence 2 years after the initial procedure.     

Intraoperative monitoring of facial nerve antidromic potentials during acoustic neuroma surgery

The present paper presents monopolar recording of facial nerve antidromic potentials as an alternative technique to facial electromyography for the continuous monitoring of the facial nerve during acoustic neuroma surgery. The investigation involved 22 patients undergoing acoustic neuroma surgery via a retrosigmoid approach (tumour sizes ranging from 5 to 28 mm). Bipolar electrical stimulation of the marginalis mandibulae was performed to elicit facial nerve antidromic potentials. Stimulus intensity ranged from 2 to 6 mA with a delivery rate of 7/sec. A silver wire monopolar electrode positioned intracranially on the proximal portion of the acoustic facial bundle was used to record antidromic potentials. To define the specific origin of the action potentials and acquire normative data, monopolar and bipolar recordings of facial nerve antidromic potentials were performed in 15 subjects undergoing retrosigmoid vestibular neurectomy for Meniere's disease. The average facial nerve antidromic potential latency was 4.2 (+/- 0.6) msec in subjects with acoustic neuroma and 3.3 (+/- 0.2) msec in subjects with Meniere's disease. Facial nerve antidromic potentials furnished near real-time information about intraoperative facial nerve damage and postoperative facial nerve function during acoustic neuroma surgery. Facial nerve antidromic potentials may provide additional information to conventional EMG. They allow the use of endplate blockers, yield quantitative estimation of facial nerve conduction properties in terms of amplitude and latency, and allow actual continuous monitoring of the facial nerve.     

"Big Smoke" has big risks: daily cigar use causes cancer, heart disease

BACKGROUND: To study the behaviour of recurrent benign parotid tumours, recurrence characteristics and problems faced with the removal of these lesions. METHODS: We reviewed the charts of the work of a single surgeon between 1971 and 1996. RESULTS: There were 24 patients (13 women, 11 men) with a mean age of 44 years at re-operation. Mean follow-up period was 10 years (range 1-22 years). There were 21 recurrent pleomorphic adenomas, two monomorphic adenomas and one patient with recurrent oncocytoma. Nine patients had solitary recurrence with a mean size of 14 mm, 15 patients had multiple recurrences with a mean size of 8 mm. There was malignant transformation of a previously benign lump in one patient. Three patients presented with a second or third recurrence. Overall facial nerve paralysis was 53% (38% temporary and 15% permanent). Frey's syndrome occurred in four patients (17%). CONCLUSIONS: Recurrent benign parotid tumours are uncommon if superficial parotidectomy (SP) is the performed initially; recurrence rates are between 0-4%. The recurrences are usually slow growing and require lengthy follow-up. Pre-operative diagnosis of a lump in the region of previous excision is useful in treatment planning. Malignant transformation in previous benign lump should be considered and fine needle aspiration biopsy may help in diagnosis. Facial nerve injury is more likely if the tumour is deep, in multiple sites or involves extensive scar tissue. Radiotherapy is controversial, it should be considered if there has been tumour spillage following re-operation.     

Benign neoplasms in the parotid gland in the county of Copenhagen 1986-1995

In a ten year period from 1986-95 433 patients were submitted to operation due to benign tumours in the parotid gland in Copenhagen County. In this study we made a retrospective analysis of the surgical outcome. The incidence was calculated to be 6.8 benign tumours in the parotid gland per 100,000 persons per year. The histological distribution showed a frequency of 54% pleomorphic adenomas, 28% adenolymphomas and 18% other tumours. In the observation period there was a 3% recurrence rate in our material, most frequently the pleomorphic adenoma. The risk of permanent damage to the facial nerve was 1% for severe injury and 3% for affection of the ramus marginalis. Frey's syndrome was present in 50% of the patients, moreover the syndrome was observed many years after surgery. The frequency rate reached its highest level about five years postoperatively.     

MRI findings of VIIth cranial nerve involvement in sarcoidosis

Right facial nerve palsy in a 58-year-old woman was due to sarcoidosis demonstrated by Gd-DTPA enhanced MRI. Abnormal enhancement of the right VIIth cranial nerve in the distal internal acoustic canal was seen on MRI. The enhancing lesion was smaller after 1 month of prednisolone 50 mg day-1. This is the first report on facial nerve involvement in neurosarcoidosis examined by Gd-DTPA enhanced MRI. The use of Gd-DTPA enhanced MRI with thin slicing, e.g. 3 mm slice thickness and 1 mm interslice gap, is effective in detecting small extramedullary lesions.     

Effect of octreotide on gastric and duodenal motility

Intraparotid facial nerve schwannomas have been documented sporadically throughout the medical literature. These benign tumours of neurogenic origin should be considered in the differential diagnosis of parotid region masses. A case report is presented, followed by a brief literature review and discussion of appropriate diagnostic and treatment modalities.     

3D reconstruction by high resolution MR tomography of the inner ear

By means of modern 3D-visualization systems it is possible to render detailed reconstructions of very small morphological structures such as the inner ear. Aim of the present study was to demonstrate the imaging quality of a new 3D-segmentation program developed in the University of Hamburg. The investigation was carried out on a high-resolution MR-tomography of the author's labyrinth and facial nerve. The images were obtained with a fast-field-echo technique using a surface coil. 32 axial slices of 1.0 mm thickness were used for reconstruction. Thus it was possible to completely visualize cochlea, semicircular canals and facial nerve. Especially the filiform substructures of the inner ear could reliably be reconstructed. So the content of information of the MR-investigation could be increased by the 3D-technique applied.     

Facial nerve neuromas presenting as acoustic tumors

Facial nerve tumors can present as masses in the internal auditory canal or cerebellopontine angle and may mimic an acoustic neuroma. These tumors can occur in any segment of the nerve from the brain stem to the neuromuscular junction. Prior to the advent of computed tomography and magnetic resonance imaging with gadolinium, facial nerve tumors were often difficult to diagnose. Even with these modalities it may be difficult to distinguish preoperatively between an acoustic neuroma and a facial schwannoma. Particular signs and symptoms associated with facial nerve tumors (in the spasms, and a facial tic. These symptoms, combined with modem radiologic studies, should allow for more accurate diagnosis, patient counseling, and treatment. This report presents a series of 32 facial nerve tumors diagnosed and treated at The Otology Group from 1975 to 1992. Of these lesions, 12 (38%) were thought to be acoustic neuromas. Eighteen tumors were correctly identified preoperatively as facial nerve tumors. Two facial nerve tumors were found incidentally.     

Solid rod short segment anterior fusion in thoracolumbar scoliosis

BACKGROUND: Facial electroneurography (ENoG) is an established and reliable method for assessing neural degeneration in various conditions affecting the facial nerve. The facial nerve may be subclinically involved by parotid tumors, but estimating such involvement preoperatively may be difficult when facial function is normal. The hypothesis that preoperative ENoG: (1) can detect subclinical facial nerve degeneration as a measure of involvement by parotid tumors and (2) can predict facial nerve function following parotidectomy was prospectively evaluated in the present study. METHODS: Twenty-two patients undergoing parotidectomy for tumors were tested preoperatively with ENoG, and their facial nerve function was graded pre- and postoperatively (House-Brackmann system). Eight patients had malignant tumors and 14 benign tumors. RESULTS: In patients with malignant tumors, lower percentage of preoperative ENoG response indicated nerve involvement that was not evident on clinical examination and correlated significantly (p = .035) with postoperative facial nerve dysfunction. Preoperative ENoG reduction of greater than 80% was found in all patients whose facial nerve was infiltrated by tumor. In 14 patients with benign tumors, preoperative ENoG results had no correlation with postoperative facial function. CONCLUSIONS: In malignant tumors, even when facial function is clinically intact, a low preoperative ENoG response may predict facial nerve involvement by the tumor. The lower the preoperative ENoG response, the poorer is the expected postoperative facial nerve function. There was no such correlation in benign parotid tumors.     

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.     

Comparison of the prognostic value between the nerve excitability test and maximum stimulation test in evaluation of Bell's palsy

In the present comparative study we applied the nerve excitability test (NET) and the maximum stimulation test (MST) to 131 patients with idiopathic facial nerve palsy. Our aim was to determine their value in the evaluation of facial nerve function. Results showed that the percentage of error of the NET in the prognosis of facial nerve palsy was 16%. In contrast, the MST was simple in its application and had a high percentage of reliability (97%). However, it remains a qualitative method, since it is dependent on the examiner's observations.     

Complement activation and CD59 expression in the motor facial nucleus following intracranial transection of the facial nerve in the adult rat

Intracranial transection of the facial nerve has been shown to cause a massive neuronal cell death in the motor facial nucleus. Complement activation has been proposed to contribute to neuronal degeneration following axotomy. Using immunocytochemistry and in situ hybridization we show in the present study that there is complement activation in the facial nucleus after intracranial facial nerve transection as well as increase of the complement regulators CD59 and clusterin. We propose a neuroprotective role for the complement regulators CD59 and clusterin against homologous attack of complement to facial motor neurons.     

Differential diagnosis in facial nerve palsy: a clinical review

BACKGROUND: The facial nerve possesses five functional components and manifests a complex course from its origin in the motor cortex to its peripheral distribution. Pathologies that impact the facial nerve in various locations along its route result in characteristic clinical manifestations that often involve other neurologic entities. CASE REPORTS: Case reports of three patients who manifested lesions of the facial nerve are presented. Each case represents a specific facial nerve pathology occurring within the supranuclear, nuclear, and infranuclear location. An anatomic, regional, and etiologic approach to the spectrum of facial nerve disorders is provided. Additionally, hyperkinetic facial disorders is discussed, and the management of facial nerve palsy is emphasized. CONCLUSION: The clinician must understand the fundamental anatomy and distribution of the facial nerve in order to localize lesions and institute the appropriate management. Abnormalities of lid position and insufficient corneal wetting are problematic. All efforts should be directed toward the maintenance of corneal integrity by appropriate wetting strategies.     

Greater petrosal nerve surgery in long-term cluster headache (author's transl)

Report on three cases with cluster headache for a period of 10 to 20 years, respectively. This was healed by resection of the greater petrosal nerve. In these patients the nerve was found in a bony canal of a length of 5 to 6 mm between the geniculate ganglion and the facial nerve hiatus. In this region the nerve was blurred free, luxated from the canal, and resected. Histological control of this part of the nerve revealed a fibrosis of the peri- and epineurium and a degeneration of some nerve fibers. Histological control in a greater number of cases is recommended.     

Results of the surgical management and histopathological evaluation of 88 parotid gland Warthin''s tumours

With the introduction of parotidectomy after identification of the facial nerve the recurrence rates for benign tumours has declined rapidly. Subsequently, attention was focused on other sequelae of parotid surgery. To reduce the specific surgical morbidity, several modifications of parotidectomy have been implemented. This study compares the results of the different surgical techniques with regard to the histopathological findings and recurrence rate for Warthin's tumour of the parotid gland. Eighty-eight primary surgical parotid procedures were performed on 85 patients for a Warthin's tumour. The surgical procedures included 52 'partial' superficial parotidectomies, 22 'standard' superficial parotidectomies, 12 partial superficial/deep lobe parotidectomies, and two 'selective' deep lobe parotidectomies. No patient developed a recurrence or experienced permanent facial nerve paresis/paralysis, the median follow-up being 93 months. Histopathological examination revealed a multifocal origin in 23% (20/88) of the surgical specimens. Partial parotidectomy is an effective treatment for Warthin's tumour. There is no need for extended follow-up.     

Peribulbar anaesthesia and needle length

This retrospective audit of 87 consecutive patients undergoing routine cataract surgery compared the effect of peribulbar local anaesthesia using 16 mm and 25 mm, 25 gauge needles to administer the anaesthetic. The effect on optic nerve function was observed. There was a significant increase of complete amaurosis in the group where the 16 mm needle had been used. This may be explained by more effective anatomic placement of the 16 mm needle within the orbit, allowing access to the retrobulbar space via fascial septae. There was significantly more lid akinesia with the 16 mm needle. None of this group required an additional facial nerve block, as opposed to 14% of the 25 mm needle group. The use of a 16 mm needle is theoretically safer than a 25 mm needle to administer a peribulbar anaesthetic, in this review it was also demonstrated to be more effective.     

Antiphospholipid syndrome associated with progressive systemic sclerosis

Hemifacial spasm is a neurological disorder due to abnormal hyperactivity of the facial nerve. The most common cause of hemifacial spasm is a neuro-vascular conflict in the cerebellopontine angle between a vascular loop and the root of the facial nerve (96% of cases). Tumors are the cause of hemifacial spasm in only 1% of cases). The authors present their results in 100 patients who underwent microvascular decompression for essential hemifacial spasm between 1990 and 1995. They used microsurgical and endoscopic procedures by a minimal retrosigmoid approach in all cases. The most common offending vessels were the posterior inferior cerebellar artery (70%), the vertebral artery (41%) and the anterior inferior cerebellar artery (28%). An aberrant vein was found in 2 cases. There were 38% of multiple artery-nerve conflicts. Physiopathology of hemifacial spasm is explained by two principal theories: in the ephaptic theory, hyperactivity and an abnormal nervous impulse pathway are due to a short demyelinated area on the nerve trunk caused by the offending vessel, inducing short circuiting between adjacent nerve fibers. In the nuclear theory, hyperactivity of the facial nerve is due to an abnormal and automatic activity of the facial nerve nucleus itself, induced by the vessel. The authors used pre and postoperative electromyographic tests and intraoperative electromyographic tests. Their results tend to prove the nuclear theory. Ninety per cent of the patients had a good result, with a mean follow-up time of 30 months in 60 cases. In 82% of the cases, there was a total recovery after a single procedure. There was no mortality and no facial palsy. Hearing loss occurred in less than 5%.     

Associations between body morphology and microalbuminuria in healthy middle-aged European, Maori and Pacific Island New Zealanders

The authors report their experience with 31 hypoglosso-facial anastomoses mainly carried out after removal of tumours of the cerebello-pontine angle, 26 were available for evaluation: at 18 months there were 5 of grade II, 19 of grade IV and 2 of grade V. Only one patient was dissatisfied with the result. 24 of the patients had received their hypoglosso-facial anastomosis using the clinical technique of Korte. In 3 cases the operation was by the technique of May. The authors suggest a variation of May's technique: it was carried out on the last 4 patients. It consists of a hemi-hypoglosso-facial anastomosis with rerouting of the mastoid portion of the facial nerve, without using a nerve graft. The aim of this technique is to reduce the sequelae of hemi-lingual atrophy and paralysis (which gives trouble with articulation, mastication and deglutition). The authors' experience confirms that these sequelae are greatly reduced, if not abolished. The functional results in terms of facial movements were satisfactory and consistant: 43.7% were quantified--with 3 of grade II and one of grade IV on the House Brackmann scale.