Neurophysiology during middle ear, mastoid and parotid surgery

Abstract

This chapter explores that intraoperative monitoring during middle ear, mastoid, and parotid surgery with the equipment and the techniques currently used is a fairly recent phenomenon. It discusses some outcomes using intraoperative monitoring as well as briefly reviews the techniques and pitfalls specific to middle ear, mastoid, and parotid surgery. It reviews that while both auditory and facial nerve monitoring accomplish many of the goals stated at the beginning of the chapter, both types of monitoring are not yet ideal. Neither type of monitoring is considered the standard of care and, while the use of facial nerve monitoring may be increasing among surgeons, there continues to be considerable resistance toward making it a standard of care. The difficulty of delivering a constant auditory stimulus to the ear, while simultaneously working through the ear canal, must be overcome for auditory monitoring. The noise and artifact during both types of monitoring must also be overcome. The chapter concludes that facial nerve monitoring is no substitute for the knowledge of facial nerve anatomy and good surgical technique. The use of a facial nerve monitor will not prevent facial nerve injury just as the use of auditory monitoring will not prevent a poor hearing outcome.