Large Intratemporal Facial Nerve Schwannoma without Facial Palsy: Surgical Strategy of Tumor Removal and Functional Reconstruction

Abstract

Three patients with large intratemporal facial schwannomas underwent tumor removal and facial nerve reconstruction with hypoglossal anastomosis. The surgical strategy for the cases was tailored to the location of the mass and its extension along the facial nerve. To provide data on the different clinical aspects of facial nerve schwannoma, the appropriate planning for management, and the predictive outcomes of facial function. Three patients with facial schwannomas (two men and one woman, ages 45, 36, and 52 years, respectively) who presented to the clinic between 2009 and 2015 were reviewed. They all had hearing loss but normal facial function. All patients were operated on with radical tumor removal via mastoidectomy and subtotal petrosectomy and simultaneous cranial nerve (CN) 7- CN 12 anastomosis. Multiple segments of the facial nerve were involved ranging in size from 3 to 7 cm. In the follow-up period of 9 to 24 months, there was no tumor recurrence. Facial function was scored House-Brackmann grades II and III, but two patients are still in the process of functional recovery. Conservative treatment with sparing of the nerve is considered in patients with small tumors. Excision of a large facial schwannoma with immediate hypoglossal nerve grafting as a primary procedure can provide satisfactory facial nerve function. One of the disadvantages of performing anastomosis is that there is not enough neural tissue just before the bifurcation of the main stump to provide neural suturing without tension because middle fossa extension of the facial schwannoma frequently involves the main facial nerve at the stylomastoid foramen. Reanimation should be processed with extensive backward mobilization of the hypoglossal nerve.