The role of continuous intraoperative neuromonitoring followed by facial nerve stimulation during parotidectomy

BACKGROUND. Intraoperative neural monitoring (IONM) has begun to be studied in detail by surgeons around the world since several decades ago from the need to verify functional integrity of the neural elements. Parotid gland surgery requires a thorough knowledge of the anatomy of this region by ENT surgeons. Also, the surgeons performing parotid surgery need to have important strategies of management which include: handiness to identify facial nerve, dissection nerve branches and application of neuromonitoring in order to preserve nerve functions.

OBJECTIVE. This study has analysed the usefulness of intraoperative continuous monitoring in superficial or in total parotidectomy. It identifies the facial nerve and reduces the risk of postoperative facial palsy. We have been using intraoperative continuous monitoring - evoked facial nerve electromyograms (EMG).

MATERIAL AND METHODS. Continuous intraoperative facial nerve monitoring was prospectively achieved in the case of three patients diagnosed with benign tumors, on which parotidectomy with the preservation of the nerve was carried out in order to highlight the value and efficacy of this method.

RESULTS. In our country, continuous intraoperative facial nerve monitoring performance is still not a common practice in ENT Departments. It revealed postoperatively that the incidence of temporary or permanent facial palsy was 0% and the minimal stimulation was obtained at levels equal to 0,5 mA, which implies integral functioning of the facial nerve.

CONCLUSION. In parotid surgery, facial nerve IONM represents the gold standard in recognition of real-time electrophysiological signals, electromyography waves and auditory signals to enable the correct approach wherever possible, avoiding extensive nerve damage. It is known the importance of continuous IONM in postoperative prognosis of the neural function and intraoperative decision making regarding the technical surgery.