[Facial Nerve Schwannomas].

Abstract

Facial nerve schwannomas (FNSs) are rare, benign tumors that can arise along segments of the facial nerve, including the cerebellopontine angle, internal auditory canal, middle fossa, and temporal bones. Although traditionally managed with gross total resection and facial nerve reconstruction, the resulting facial nerve palsy has prompted a paradigm shift toward functional preservation. Based on>70 surgical cases, we established a tailored strategy based on preoperative facial nerve function and intraoperative facial nerve electromyograms. Patients with mild-to-moderate palsy underwent facial nerve preservation surgery with subtotal resection and osseous decompression under continuous intraoperative monitoring to preserve and improve facial nerve function. Patients with severe palsy underwent total resection with nerve reconstruction. We proposed a practical five-type classification based on the primary tumor location to guide the surgical approach. Cerebellopontine angle-type FNSs may present without facial symptoms, mimicking vestibular schwannomas, particularly if the labyrinthine segment or geniculate ganglion is not involved. In such cases, radical resection should be avoided to ensure functional preservation. To balance long-term tumor control with optimal facial nerve function, comprehensive surgical expertise is required, including detailed anatomical knowledge, diverse skull-base approaches, intraoperative monitoring, nerve reconstruction techniques and flexible surgical planning that allows for intraoperative modification.