Intra—Operative Facial Nerve Monitoring in Acoustic Neurinoma Surgery

Objective To determine the method and significance of facial nerve preservation during acoustic neurinoma surgery by intra-operative facial nerve monitoring(IFNM).Methods 62 patients were randomly assigned to the IFNM or the control group.Facial nerve function(FNF)was assessed by a modified House-Brackmann grading(HB)before the operation,10 days and every two months after surgery and com,pared between the two groups. Results Ten days after surgery,26/32 patients in the IFNM group and 15/30 patients in the control group had FNF HB grade,Ⅰ-Ⅲ；FNF HB gradeⅣ-Ⅴ was prestent in 6/32 in the IFNM group and 15/30 in the control group.During follow-up,29/32 patients in the IFNM group and 20/20 patients in the control group had FNF HB gradeⅠ-Ⅲ;FNF HB gradeⅣ-Ⅴ was present in 3/32 in the IFNM group and 10/30 in the control group.All differnces were statistcally significant.Conclusion IFNM significantly improved anatomic and functional facial nerve preservation as well as the quality of life.