Comparison of masseter VEMP responses in normal hearing individuals and individuals with sensorineural hearing loss

This study was conducted to compare the EMG measurement parameters of normal hearing individuals and individuals with sensorineural hearing loss by applying mVEMP test with airway 500 Hz tone burst stimulus. The study was performed on a total of 32 individuals (n= 64 ears), 16 females and 16 males. The individuals who voluntarily participated in the study were first evaluated with pure tone audiometry test and then mVEMP test was performed. A statistically significant positive correlation (r=0.929) was found between the mean hearing loss and P1N1 Threshold after mVEMP measurement (p<0.001). A statistically significant statistically significant relationship was found between the mean hearing loss and P1 Latency and N1 Latency (r=0.510 and r=0.413, respectively) (p<0.001). There was no statistically significant correlation between the mean hearing loss and P1N1 Interpeak (r=-0.179 and p<0.001). The comparison of the group averages in terms of P1N1 Amplitude was performed by independent two sample t-test. The normal group mean (12.23±1.23) was found to be statistically significantly lower than the hearing loss group mean (33.82±1.96) (Table 3, p<0.001). While there was a statistically significant difference between the groups in P1 asymmetry measurements, there was no statistically significant difference in N1 asymmetry measurements. In terms of P1 measurements, the normal group mean (0.9±0.42) was statistically significantly higher than the hearing loss group mean (0.63±0.32) (Table 4, p=0.049) (Bogle et al, 2013; Welgampola & Colebatch, 2005)In individuals with normal hearing and normal vestibular activity, the threshold mean intensity value at which P/N1 waves were last measured was 83dB.In the same group, the mean P1 latency value was 18.291ms and the mean N1 latency value was 24.698ms.In individuals with sensorineural type hearing loss but normal vestibular activity, the threshold mean intensity value at which P1/N1 waves were last measured was 98dB. In the same group, the mean P1 latency value was 19,437ms and the mean N1 latency value was 25,531ms. Accordingly, it was observed that the threshold of P1/N1 wave was increased in individuals with hearing loss compared to individuals with normal hearing, and there was no significant difference in latency values. In conclusion, the vestibulo-acoustic masseter reflex showed differences in parameters in the presence of cochlear pathology compared to normal hearing, which was found to be important in terms of differential diagnosis. It was thought that it could be used as a diagnostic test in the evaluation of the trigeminal pathway and in the evaluation of patients with various cochlear disorders.