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At least 937 records · Page 52Linked to original sources
PubMed1990

Functional results of facial nerve suture after removal of acoustic neurinoma: analysis of 25 cases.

The facial nerve is sometimes severed during the removal of acoustic neurinomas, either intentionally to ensure complete removal, or unintentionally because of difficulties in identification. In such cases we have, if possible, sutured the nerve stumps microsurgically, either end to end or by use of an intervening nerve graft. We analyzed the outcome of 25 instances of facial nerve suturing in a series of 219 patients operated on for acoustic neurinoma from 1979 to 1987. The first signs of recovery appeared at an average of 12 months, and there was continued improvement for several years. Recovery was graded from 1 to 6. The anastomosis was successful in 24 of the 25 sutured nerves, in that at least some facial movement and tone were restored (Grade 5 or higher). In 11 of the 25 cases, facial appearance at rest and with movement was moderately good (Grade 2 or 3). A Grade 1 result, with no perceivable facial dysfunction, was never achieved. Typically, oral muscles showed the most improvement and frontal muscles the least. Facial appearance was better at rest than with movement, which was always complicated by some degree of synkinesis. Closure of the eye was so good in 13 of the 25 cases that neither tarsorrhaphy nor an eyelid spring was necessary. When the facial nerve is severed, intraoperative suture is recommended, because it provides a chance for moderately good restoration of facial appearance.

Evaluation Studies as Topic↗
PubMed1997

Management of 1000 vestibular schwannomas (acoustic neuromas): the facial nerve--preservation and restitution of function.

OBJECTIVE: Although the rate of reported facial nerve preservation after surgery for vestibular schwannomas continuously increases, facial nerve paresis or paralysis is a frequent postsurgical sequelae of major concern. The major goal of this study was to define criteria for the right indication, timing, and type of therapy for patients with palsies despite anatomic nerve continuity and those with loss of anatomic continuity. METHODS: One thousand vestibular schwannomas were surgically treated at the Department of Neurosurgery at Nordstadt Hospital from 1978 to 1993. Of 979 cases of complete removal and 21 cases of deliberately partial removal, the facial nerve was anatomically preserved in 929 cases (93%). The rate of preservation is increasing, as is evidenced in the most recent cases, and preservation is supported by special electrophysiological monitoring. The facial nerve was anatomically severed in 60 cases (6%). It was anatomically lost in previous operations that were performed elsewhere in 11 cases (1%). In case of nerve discontinuity (42 cases), immediate nerve reconstruction by one of three available intracranial procedures (within the cerebellopontine angle, intracranial-intratemporal, intracranial-extracranial) was performed in the same surgical setting. In case of loss of the proximal facial nerve stump at the brain stem, early reanimation by combination with the hypoglossal nerve was achieved in most patients within weeks after tumor surgery. In a few patients with anatomic nerve continuity but absence of reinnervation for 10 to 12 months, a hypoglossal-facial combination was applied. All the patients with partial or with complete palsies were treated in a special follow-up program of regular controls and of modulation of physiotherapeutic treatment every 3 to 6 months. RESULTS: In intracranial nerve reconstruction at the cerebellopontine angle, 61 to 70% of patients regained complete eye closure and an overall result equivalent to House-Brackmann Grade 3. Hypoglossal-facial reanimation led to Grade 3 in 79%. The duration between the onset of paralysis and the reconstructive procedure is decisive for the quality of the outcome. These data are discussed in view of other treatment options and certain parameters influencing outcome. CONCLUSIONS: This management contains three major principles as follows: 1) preservation of facial nerve continuity in function by the aid of intraoperative monitoring, 2) early nerve reconstruction in case of lost continuity, and 3) scheduled follow-up program for all patients with incomplete or complete palsies.

Adolescent↗
PubMed1994

Recovery of the sutured facial nerve after removal of acoustic neuroma in patients with neurofibromatosis-2.

The authors compared the long-term recovery of sutured facial nerves after the removal of 8 neurofibromatosis-2 (NF2)-associated and 22 non-NF2 acoustic neuromas. The patients were from a series of 270 patients operated on for an acoustic neuroma between 1979 and 1989. The assessment was done with a modified House and Brackmann scale from video recordings. At least some facial movement or tone was achieved (Grade 5 or better) in all but three patients, but in none was the recovery excellent. The facial function, judged by the overall appearance in movement, recovered less in patients with NF2 (P = 0.048); a moderately good recovery (Grade 3 or better) was seen in one patient of eight with NF2, as compared with 13 of 22 with non-NF2. In conclusion, if the tumor cannot be peeled off easily from the facial nerve in patients with NF2, leaving a fragment of tumor behind is preferable to cutting and suturing the facial nerve.

Adolescent↗
PubMed1984

Facial nerve function after suboccipital removal of acoustic neurinoma.

The recovery of facial nerve function after suboccipital removal of 91 acoustic neurinomas is presented. The results after anatomical preservation of the nerve (60 cases), direct anastomosis of the nerve (7 cases), nerve grafting (16 cases), and facial hypoglossal anastomosis (8 cases) are presented after a follow-up period of 31.2 months. A simplified classification was used to describe motor function. The results are compared to those in the literature.

Adolescent↗
PubMed2004

Effects of transitory lingual nerve impairment on speech: an acoustic study of diphthong sounds.

PURPOSE: The effects of lingual nerve impairment on the phonetic quality of diphthongs were studied by analyzing changes in their main acoustic features when anesthetic was injected into the lingual nerve to partly block the normal neural feedback mechanisms in speech. PATIENTS AND METHODS: The speech material consisted of 8 diphthongs in word context produced by 7 male speakers. Every utterance was repeated 10 times using normal speech rate and intonation with and without the anesthesia (Ultracain D-Suprarenin, 0.8 mL; Aventis Pharma Deutscland GmpH, Frankfurt am Main, Germany). In addition, 1 male speaker with permanent nerve impairment was studied. The acoustic features (F1, F2, F0, and duration) were analyzed using Computerized Speech Laboratory (CSL 4300B; Kay Elemetrics, Lincoln Park, NJ). RESULTS: At the group level, no general significant acoustic changes were found between the 2 conditions. The changes were highly individual and variable across the subjects. Significant changes were observed for all the subjects, most prominently for the subject with permanent nerve impairment. CONCLUSIONS: According to the results, lingual nerve impairment has effects on the production of diphthongs. A comparison between monophthongs and diphthongs showed that the alterations are more significant for the diphthongs than for other vowels indicating the more demanding, complicated, and complex manner of articulation of diphthongs.

Adult↗
PubMed1994

Electrophysiological characterization of pre- and postoperative facial nerve function in patients with acoustic neuroma using electrical and magnetic stimulation techniques.

Facial nerve function was examined in patients who underwent posterior fossa surgery for unilateral acoustic neuroma. Examinations took place prior to surgery (n = 47 patients), early after surgery (0-12 days, n = 16 of 47 patients), and late after surgery (187-1505 days, n = 29 of 47 patients). Clinical signs of facial palsy were present to a variable extent in 13 of 47 patients before, in 12 of 16 patients early, and in 18 of 29 patients later after surgery. Electrophysiologically, the facial nerve was stimulated electrically at the stylomastoid fossa and magnetically at its proximal intracanalicular segment. In addition, the face-associated motor cortex was stimulated magnetically. In patients with facial palsy, any of these stimulation methods resulted in a decreased amplitude of the response in the nasalis muscle. The decrease showed a linear relationship to the clinical grade of palsy, pre- and postoperatively. Corticomuscular latencies remained unchanged. We conclude that: (i) the electrophysiological characteristics of facial nerve lesions due to compression by acoustic neuromas or due to a complication of neuroma removal are those of a purely axonal neuropathy; (ii) the three stimulation techniques have a similar diagnostic yield, thus making the use of all three of them redundant; and (iii) the electrophysiological techniques allowed no prediction of the final facial nerve function.

Adult↗
PubMed1981

Inhibition of intracranial self-stimulation in brain stem-transected cats--a proposed mechanism of aversive effects produced by brain stimulation.

Effects of intracranial self-stimulation of central 'punishment areas' were studied on an operant conditioning of vertical eye movements in the midpontine pretrigeminal cats as well as in the encéphale isolé cats. In 36 pretrigeminal cats, the ventromedial hypothalamus (VMH), basal amygdaloid nuclei (AMY), dorsal central gray (CG) of the midbrain and the thalamic nuclei such as the ventralis posteromedialis (VPM) and ventralis posterolateralis (VPL) were tested. No suppression of eye movements indicating a passive avoidance conditioning from stimulation of these 'punishment areas' was obtained in 92 electrode tip sites. In 49 encéphale isolé cats, stimulation of the VPM associated with contraction of the facial muscles, demonstrated a marked passive avoidance effect on the eye movements. After blocking both the trigeminal (5N) and facial nerves (7N), VPM stimulation no longer produced an increase of facial EMG activity and the suppressive effect on eye movements was abolished. Extracranial blockade of 7N alone, which induced facial muscle paralysis also showed similar effects. Bilateral blockade of cranial nerves from acoustic (8N) to hypoglossal (12N) nerves had no significant effect on the avoidance conditioning. The mass neural activity recorded from the 5N showed a marked increase of discharge by VPM stimulation which was reduced significantly after 7N blockade. These results may suggest a possibility that punishing effects of brain stimulation depend on feedback from the periphery (muscles, blood vessels and visceral organs), whereas reward effects essentially depend on neural circuitry confined within the forebrain above the rostral pons.

Amygdala↗
PubMed1997

[Factors influencing the long-term function of the facial nerve following removal of acoustic neurinomas].

Thirty-five cases with removal of acoustic neurinomas were reviewed to demonstrate the factors which influenced the postoperative long term function of the facial nerve. All cases were operated on via a suboccipital route. The group consisted of 7 cases with the tumor confined to the internal auditory meatus, 4 cases with a neurinoma of 20 mm or less in diameter, 13 cases with a neurinoma of 30 mm or less, and 11 cases with a neurinoma over 30 mm. The consistency of the tumors was solid in 27 cases, and cystic in 8 cases. Dislocation of the facial nerve was observed during the operation except in 7 intrameatal cases. The dislocation is summarized as follows: dislocated in the cranial direction in 2 cases, ventrocranial in 7, ventral in 5, ventrocaudal in 10, dorsocaudal in one, and caudal in 3 cases. No case showed dislocation of the facial nerve in the dorsocranial or dorsal direction. Careful observation of the facial nerve at the entrance of the internal auditory meatus showed a severe kinking in 2 cases, moderate kinking in 2, but no kinking at all in the remaining 31 cases. The facial nerve was preserved anatomically in all cases. Long term function of the facial nerve can be summarized as excellent in 18 cases, good in 8 cases, and poor in 9 cases. Three cases showed an almost complete paresis of the facial nerve immediately after the operation and recovery was never observed. Neurinoma facial score was defined in 28 cases, except intrameatal cases, according to the degree of preoperative facial nerve function, tumor size, presence of the cystic component within the tumor, direction of the facial nerve dislocation, and the presence of kinking of the facial nerve. The correlation between the long-term facial nerve function and the neurinoma facial score was statistically examined and was found to be significant (Sperman's correlation coefficient by ranks; rs = 0.38596 > 0.375; P = 0.05). In conclusion, neurinoma cases that show the least facial nerve function are: cases in which facial function had deteriorated, cases in which the tumor was large or when the tumor had no cyst, when dislocation of the facial nerve was in the cranial direction, and in cases where there was kinking of the facial nerve at the internal auditory meatus. In such cases, the removal should be carried out intracapsularly so as to preserve facial nerve bundle which may spread and become flattened like a tumor capsule. This might minimize the postoperative deterioration of the facial nerve function.

Adult↗
PubMedDate not supplied

Pre- and postoperative facial nerve testing in patients with acoustic neuromas.

Clinical and electrophysiological examination of the facial nerve was performed in 49 consecutive patients, from December 1982 to January 1984, before and after surgical removal of acoustic neuroma. The electrophysiological examination included quantitative electromyography of the facial muscles and facial nerve stimulation with registration of amplitude and latency of evoked muscle potentials. 17 patients had tumours with an extrameatal size of 5-25 mm, 16 had tumours between 26 and 40 mm, and 16 (32%) tumours larger than 40 mm. At preoperative clinical examination, 9 patients had decreased facial motor function; 7 however, only by meticulous inspection, while 2 had a slight paresis. Two patients had hemifacial spasms. 25 patients had prolonged duration of motor unit potentials and/or increased incidence of polyphasic potentials by electromyography. Only one patient had denervation activity. Three patients had decreased amplitude of evoked muscle potentials to supramaximal stimulation of the facial nerve. Motor latency was normal. At the most recent examination between 3 and 12 months postoperatively, 65% of the patients had no or insignificant facial nerve involvement, 10% had slight and 25% significant involvement, of whom 6 had paralysis or only slight reinnervation. The preoperative clinical facial involvement and the degree of electrophysiological abnormality was poorly correlated to the motor function at the time of the most recent examination.

Adolescent↗
PubMed2005

Facial nerve rerouting in skull base surgery.

Facial nerve rerouting techniques were developed to facilitate re-section of extensive tumors occupying the skull base. Facial nerve rerouting has its own limitations and risks, requiring microsurgical expertise, additional surgical time, and often some degree of facial nerve paresis. This article presents different degrees of anterior and posterior facial nerve rerouting, techniques of facial nerve rerouting, and a comprehensive review of outcomes. It then reviews anatomic and functional preservation of the facial nerve in acoustic neuroma resection, technical aspects of facial nerve dissection, intracranial facial nerve repair options, and outcomes for successful acoustic neuroma surgery.

Cranial Fossa, Middle↗