Abstract: Objective The present study aims to investigate the indications of subtotal resection of facial nerve schwannoma with facial nerve-preserving surgery for patients with mild facial nerve paralysis(HB Ⅰ-Ⅱ)and obvious accompanied symptoms. Methods A retrospective analysis of the clinical data of three cases of facial nerve schwannoma that underwent subtotal resection with facial nerve-preserving surgery was conducted. The analysis encompassed the clinical manifestations, auxiliary examinations, operative approaches, and postoperative prognoses. Results Of the three patients, one exhibited facial nerve function of HB Ⅱ prior to surgery, while the other two demonstrated normal facial nerve function preoperatively. Preoperative imaging findings demonstrated that the mass had grown along the course of the facial nerve. Among the patients, one individual exhibited no symptoms of facial palsy prior to surgery, yet EMG results indicated facial nerve impairment. Subtotal resection of the facial nerve schwannoma was performed under intraoperative facial nerve electrophysiological monitoring. Post-operative observations revealed that the function of the facial nerve had been well preserved. Furthermore, no significant changes to facial nerve function were observed in the immediate post-surgical period. Furthermore, no substantial alterations in facial nerve function were detected during the extended follow-up period of up to three years. Conclusion For patients with facial nerve schwannoma, if the patient's facial nerve function is graded HB Ⅱ or better at the time of surgery, and the patient has strong desire to preserve facial nerve function, then subtotal resection of the facial nerve schwannoma can be contemplated, with this being performed under electrophysiological monitoring during surgery.

Key words: Facial nerve schwannoma, Subtotal resection, Facial nerve function, Intraoperative electrophysiological monitoring, Facial nerve electromyography