The auditory system is placed at risk during a variety of surgical procedures involving access to and manipulation in the posterior cranial fossa. During the course of such operations, monitoring of the auditory system can help identify critical anatomical structures or provide an early warning to forestall potential permanent damage. To realize the benefits of monitoring, all members of the care team, including the surgeon, the anesthesiologist, and the neurophysiologist, should be knowledgeable about surgical objectives, anatomical relationships, and technical constraints of the monitoring modality as well as effects of surgical interventions and anesthesia on monitored parameters. The first section reviews important anatomical relationships as they relate to auditory function and recorded potentials. The second section discusses technical aspects of each monitoring modality. Finally, the third section briefly describes technical and physiologic problems that may cause changes in intraoperative monitoring.
KeywordsAuditory brainstem-evoked potentials Ear Cochlea Electrocochleogram Auditory pathway Techniques Recording Stimulation Anesthetic considerations Physiologic considerations
Radiographic and anatomic location of generators of BAEPs. The MRI images in the on-line video were provided by Reordan O. DeJesus, MD, Department of Radiology, University of Florida. The narrative was done by Erin Rathbone (MP4 111,628 kb)
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