Abstract
Objective
To elucidate the long-term clinical behavior, treatment, and outcomes of sporadic
facial nerve schwannoma (FNS) in a large cohort of patients managed in the post–magnetic
resonance imaging era.
Patients and Methods
Retrospective review at a single tertiary health care system (January 1, 1990, through
December 31, 2015), evaluating 80 consecutive patients with sporadic FNS.
Results
Ninety-eight patients with FNS were identified; 10 with incomplete data and 8 with
neurofibromatosis type 2 were excluded. The remaining 80 patients (median age, 47
years; 58% women) were analyzed. Forty-three (54%) patients presented with asymmetrical
hearing loss, 33 (41%) reported facial paresis, and 21 (26%) reported facial spasm.
Seventeen (21%) exhibited radiologic features mimicking vestibular schwannoma, 14
(18%) presented as a parotid mass, and 5 (6%) were discovered incidentally. Factors
predictive of facial nerve paresis or spasm before treatment were female sex and tumor
involvement of the labyrinthine/geniculate and tympanic facial nerve segments. The
median growth rate among growing FNS was 2.0 mm/y. Details regarding clinical outcome
according to treatment modality are described.
Conclusion
In patients with FNS, female sex and involvement of the labyrinthine/geniculate and
tympanic segments of the facial nerve predict a higher probability of facial paresis
or spasm. When isolated to the posterior fossa or parotid gland, establishing a preoperative
diagnosis of FNS is challenging. Treatment should be tailored according to tumor location
and size, existing facial nerve function, patient priorities, and age. A management
algorithm is presented, prioritizing long-term facial nerve function.
Abbreviations and Acronyms:
AAOHNS (American Academy of Otolaryngology-Head and Neck Surgery), CPA (cerebellopontine angle), CT (computed tomography), FNS (facial nerve schwannoma), GTR (gross total resection), HB (House-Brackmann), IAC (internal auditory canal), MRI (magnetic resonance imaging), NF2 (neurofibromatosis type 2), SRS (stereotactic radiosurgery), STR (subtotal resection)To read this article in full you will need to make a payment
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Article Info
Publication History
Published online: October 05, 2016
Footnotes
Grant Support: Internal departmental funding was used without commercial sponsorship or support.
Potential Competing Interests: Dr Carlson is a consultant for MED-EL GmbH. Dr Driscoll is a consultant for Advanced Bionics Corp., Cochlear Corp., and MED-EL GmbH.
Identification
Copyright
© 2016 Mayo Foundation for Medical Education and Research
