A Prospective Study of Intra Operative Nerve Monitoring of Facial Nerve in Parotid Surgery

The aim of this study is to describe the intra‑operative application of IFNM andreporting postoperative facial‑nerve outcomes in a consecutive series ofparotidectomies performed with routine IFNM.Methodology: This prospective study included 23 patients who underwent surgery forparotid gland tumors. Intra Operative Facial Nerve Monitoring (IFNM) was used in allpatients during surgery. Facial nerve function after surgery was assessed using postparotidectomy facial nerve grading system (PPFNGS). The mean age of participants was 28.96 ± 16.03 years, 57% were male and43% were female. Twenty-two patients underwent superficial parotidectomy and threepatients with revision parotidectomy. Facial nerve monitoring setup averaged 6.91minutes, with successful nerve monitoring in all cases. In two patients, IFNM was usedwith long-acting NMBA, and the return of nerve activity was observed in main trunk andtemporofacial division of facial nerve as effect of these muscle relaxant faded.Postoperatively, facial nerve function assessed using PPFNGS showed facial nerveparesis in 30.43% cases predominantly affecting mandibular and buccal branches, withslight improvement over three months. Histopathological analysis revealed 82.6%benign tumours, predominantly pleomorphic salivary adenoma. Postoperativecomplications included facial paresis (30.43%), hypoesthesia (17.39%), and sialoceleformation (8.7%). The study highlights that IFNM facilitated facial nerve identification,branches tracking and dissection in all, especially in revision parotid surgeries. IFNM isa useful tool for teaching, ease of mind of surgeon and patient counselling andmedicolegal purpose.