Abstract:
Meniere's disease is mainly a labyrinthine pathology; however, other labyrinthine pathologies such as NIHL and ototoxicity have shown that neural involvement begins to occur with disruption of the hair cell within the cochlea. This phenomenon of neural involvement has been linked to the "dying back" of the neurons due to the absence of inputs from the hair cell. Considering the later stage of Meniere's disease, which includes considerable hearing loss, a similar "dying back" of the neuron might be expected, leading to poor performance on speech audiometry; however, this remains unexplored. Hence, the study aimed to investigate the effect of Meniere's disease and its stages on the outcome of speech audiometry. Two groups of participants (age range: 18-60 years) were considered, one with Meniere's disease (N=89) and the other with non-Meniere's cochlear hearing loss (N=108), and they were classified into four stages based on the pure tone average thresholds. The comparison of SIS, SRT and SRT-PTA difference between Meniere's disease and cochlear hearing loss group showed significant difference only at stage III. This indicates pathology restricting to the cochlea till stage II and a beginning of neural involvement due to dying back in stage III of Meniere's disease group.
