Brainstem auditory evoked potential monitoring: when is change in wave V significant?

Journal Article

BACKGROUND: The probability of hearing loss during cerebellopontine angle (CPA) surgery can be reduced by using brainstem auditory evoked potential (BAEP) intraoperative monitoring (IOM). A wave V latency prolongation of 1.0 milliseconds or amplitude decrement of greater than 50% is arbitrarily considered the point when damage to hearing occurs. OBJECTIVE: To determine the accuracy of wave V changes in predicting hearing impairment. METHODS: Patients undergoing BAEP IOM for surgery in the CPA region were evaluated. The greatest wave V latency and amplitude change was determined. Patients were divided into four groups depending on degree of change of wave V: Group 1 consisted of minimal change, whereas Group 4 was permanent loss of wave V. The frequency of hearing loss in each group was compared. RESULTS: Data from 156 patients were reviewed. When all patients were analyzed, the frequency of hearing loss was not significantly different between the groups. When patients with CPA tumor were excluded, a significantly higher number of patients in Group 4 had hearing loss. Analysis of the patients with CPA tumor showed no difference in the frequency of hearing loss in any of the groups; even a large number (50%) of Group 1 patients had hearing impairment. CONCLUSIONS: During brainstem auditory evoked potential intraoperative monitoring, the type of surgery is important when interpreting significance of changes of wave V. For non-cerebellopontine angle tumor surgery, hearing loss occurs usually only with permanent loss of wave V; much smaller changes may be important in cerebellopontine angle tumor surgery.

Full Text

Duke Authors

Cited Authors

  • James, ML; Husain, AM

Published Date

  • November 22, 2005

Published In

Volume / Issue

  • 65 / 10

Start / End Page

  • 1551 - 1555

PubMed ID

  • 16301480

Electronic International Standard Serial Number (EISSN)

  • 1526-632X

Digital Object Identifier (DOI)

  • 10.1212/01.wnl.0000184481.75412.2b

Language

  • eng

Conference Location

  • United States