Evaluation of Cervical Vestibular Evoked Myogenic Potential in Subjects with Chronic Noise Exposure.

Abstract

Noise has been recognized as a major cause of cochlear damage resulting in both tinnitus and hearing loss. On the other hand, damage to the vestibular system, especially the saccule, can be considered as a potential problem. The cervical vestibular-evoked myogenic potentials (cVEMPs) have been established as a clinical test of measuring both sac-cular and inferior vestibular nerve function. Therefore, it is thought to be sensitive to the noise-induced damage to the vestibular system. Accordingly, this study was designed to assess the vestibular system in subjects exposed to noise during work by using cVEMPs. This study was performed in over 60 adult males who were divided into a study group (consisting of 40 adult males) with history of chronic occupational noise exposure and with variable degree of hearing levels and a control group consisting of 20 healthy adults with normal peripheral hearing, with no history of noise exposure and no vestibular complaints. cVEMP recordings were elicited using 95dB nHL click stimuli. There was statistically significant prolonged cVEMP latency of the P13 and N23 waves of the study versus the control groups. As regard to the sense of imbalance, there were significant prolonged cVEMPs latencies in present versus absent sense of imbalance. However, there were statistically insignificant reduced cVEMP amplitudes in present versus absent sense of imbalance. Chronic noise exposure damages the vestibular system especially the saccule in addition to cochlear damage.