Use of an infrared camera to improve the outcome of facial nerve monitoring.

Intraoperative cranial nerve neuromonitoring (IONM) has significantly reduced morbidity historically associated with skull-base procedures. It provides the surgeon with immediate feedback to preserve both anatomic and physiologic function of monitored nerves. However, when the surgeon cauterizes tissue near the nerve, the monitoring equipment is saturated by the cautery signal, eliminating IONM information at a critical time. The use of an infrared camera under the drapes to observe the face for movement due to nerve stimulation is an invaluable adjunct to traditional IONM. Monitoring may also be improved by contralateral electrode placement to help identify artifact from nerve stimulation, using the microscope's video output to compare the surgeon's hand movements to recorded activity, and learning basic anatomy of the inner ear and skull base in order to know when heightened attention is important.