Facial nerve schwannoma

Fascicle preservation surgery for facial nerve neuromas involving the posterior cranial fossa

OBJECTIVE

To assess facial nerve function after fascicle preservation surgery in cases of facial nerve neuroma involving the cerebellopontine angle.

STUDY DESIGN

Retrospective case series and literature review.

SETTING

Tertiary referral center.

PATIENTS

Seven patients with facial nerve neuroma involving the posterior cranial fossa were reviewed from a single neurotologist's practice and combined with a review of 648 cases reported in the literature.

INTERVENTIONS

Translabyrinthine resection was used in all patients for complete tumor removal. Nerve reconstruction was accomplished with fascicle preservation (three cases), cable nerve interposition grafting (three cases, one of which involved using cranial nerve VIII as the graft), or direct anastomosis (one case).

MAIN OUTCOME MEASURE

Facial nerve function as measured by the House-Brackmann grading system. RESULTS A postoperative facial nerve (House-Brackmann) grade of II/VI was obtained in two of our three patients who underwent fascicle preservation reconstruction and in two of eight cases reported by other authors. One case reported elsewhere resulted in grade I/VI, and four other cases reported elsewhere achieved grade III/VI; only two cases were grade V/VI. There were no tumor recurrences at 5 to 19 years of follow-up.

CONCLUSION

Most cases of facial nerve neuroma require facial nerve resection. In rare cases, these tumors can be dissected away from the nerve fascicles, allowing the surgeon to preserve the facial nerve. This method resulted in better long-term postoperative facial nerve function (House-Brackmann grade II/VI vs. grade III/VI) compared with other techniques for patients in this small series, and no tumor recurrence.

Facial schwannoma without facial paralysis

A 64-year-old man with right aural discharge presented complaining of progressive deafness. Other otological symptoms were absent and specifically there was no seventh nerve paresis. A right aural polyp was identified and biopsied. Histology showed the polyp to be a schwannoma. Subsequent temporal bone computed tomography showed expansion of the distal facial canal. At operation, the schwannoma filled the middle ear cleft and extended from the genu to the region of the stylomastoid foramen. The floor of the middle ear had been eroded, exposing the jugular bulb. Facial paresis is the usual presenting feature of a facial schwannoma, while deafness, ageusia and reduced lacrimation are variable, dependent upon the site of the lesion. The absence of facial palsy as a presenting feature is very rare and this case illustrates the need for histological examination of all abnormal aural material.

Intracranial and intratemporal facial neuroma

Primary tumors of the facial nerve are relatively rare and have a variety of presenting symptoms. This article reviews 248 cases of facial neuroma in the world's literature and adds seven cases that were managed at the Baylor College of Medicine. Facial weakness was most common symptom, with facial spasm or tics, hearing loss, and masses in the external auditory canal also being frequently seen. At surgery, the tympanic, vertical, and labyrinthine segments were the most commonly involved areas. On the basis of this review, general principles have been drawn up to help the clinician in diagnosis and management of this (at times) difficult problem.

Intrapetrous neurinomas of the facial nerve. Report of three cases

Three cases of intrapetrous neurinomas of the facial nerve are reported and their diagnostic and surgical problems are discussed. Two of them revealed rare intracranial extensions and the other was a typical intrapetrous expansion of the tumor. The literature of intracranial neurinomas of the facial nerve is reviewed in detail.