Evaluating the Benefits of Intraoperative Neurophysiological Monitoring

Abstract

Guidelines for intraoperative monitoring have been issued by various bodies. The Therapeutics and Technology Subcommittee of the American Academy of Neurology has concluded that the following are useful and noninvestigational: (1) EEG, compressed spectral array, and somatosensory evoked potential (SSEP) in CEA and brain surgeries that potentially compromise cerebral blood flow, (2) auditory brainstem response (ABR) and cranial nerve monitoring in surgeries performed in the region of the brainstem or inner ear, and (3) SSEP monitoring performed for surgical procedures potentially involving ischemia or mechanical trauma of the spinal cord (44). Earlier, the National Institutes of Health Consensus Development Conference (held December 11–13, 1991) stated in a “Consensus Statement” that

There is a consensus that intraoperative realtime neurologic monitoring improves the surgical management of vestibular schwannoma, including the preservation of facial nerve function and possibly improves hearing preservation by the use of intraoperative auditory brainstem response monitoring. Intraoperative monitoring of cranial nerves V, VI, IX, X, and XI also has been described, but the full benefits of this monitoring remains to be determined.