Cervical Vestibular-Evoked Myogenic Potentials Using Vibration and Sound in Normal Subjects

Na, Bo Ra; Han, Soo Hee; Ha, Eun Jung; Lee, Yeo Jin; Park, Mun Su; Kim, Jae Myung; Shin, Jung Eun; Park, Hong Ju

Abstract

BACKGROUND AND OBJECTIVES
The aim of this study was to investigate and compare the incidence and the characteristics of parameters of cervical vestibular-evoked myogenic potentials (cVEMPs) using air-conducted (AC) and bone-conducted (BC) stimulations in normal subjects.
SUBJECTS AND METHOD
Twenty-four normal subjects (48 ears) with normal hearing and no previous history of dizziness were included. cVEMP responses were recorded by surface electrodes on sternocleidomastiod muscles in response to AC and BC stimuli sequentially. Variances of parameters, including thresholds, amplitudes and interaural amplitude difference ratios (IADR), were analyzed and compared.
RESULTS
cVEMP responses were clearly observed in all 48 ears in both AC and BC cVEMP tests. There was no significant difference in latencies (p1 and n1). However, the thresholds in BC cVEMP testing were significantly lower than those in AC cVEMP testing, when compared to the maximum stimulation level. Interaural amplitude difference ratios showed no significant difference in between the two tests, although amplitudes at maximum stimulation intensity in BC cVEMP testing were significantly larger than those in AC cVEMP testing.
CONCLUSION
This study shows that BC cVEMP testing shows lower thresholds compared to AC cVEMP testing in normal subjects, suggesting that the threshold value can be used as a parameter in detecting vestibular dysfunction in the clinic. Further studies in patients with various vestibular disorders are needed.