DOI: 10.36347/sjams.2014.v02i06.121

Pages: 3445-3451

It has been established that the seismic sensitivity of the human vestibular system exceeds that of the cochlea for low-frequencies. The objective of this work is to determine spurious low frequency air bone gap (slABG) observed in some patients with severe sensorineuronal hearing loss (sSNHL) is due to vestibular otolith organ perception. Study design was Cross-sectional study. Twenty normal volunteers and twenty age-matched patients with sSNHL were included in this study. The participants were undergone comprehensive audiologic tests, cervical vestibular-evoked myogenic potentials (cVEMPs), and thin-sliced computerized tomography scans (CT) at the audiology department of Hamadan University of Medical Sciences, Iran. The observed slABG in the patients group was disappeared at frequencies over 1000Hz. Mean value for slABG was 38.7 dB, 29.3 dB, 20.4 dB and 13.9 dB for frequencies of 250, 500, 750 and 1000 HZ, respectively. We observed twenty three ears with sSNHL showed slABG>10 dB and abnormal cVEMPs (affected). Seventeen ears without slABG>10dB had normal cVEMPs (unaffected). Normal group had normal cVEMPs. None of the patients showed Tullio sign or noise- pressure-induced nystagmus, or third window type symptoms during exam and testing periods. All CT were normal. Statistical analysis of the peaks latency and amplitude of cVEMPs among three groups revealed significant differences (P = 0.039, one-way ANOVA test, Tukey HSD). Higher threshold for bone-conduction at low-frequencies in the ears with SSNHL may be due to stimulation of the otolith organs. We assumed that the observed slABG is not due to vibrational sensation.