Summary
The present study was carried on forty-five patients of confirmed hypothyroidism. Complete clinical examination and laboratory investigations were done regarding audiological and vestibular system. It was found that hypothyroidism affects the ear at multiple sites producing various types of hearing impairment viz. conductive, sensorineural and mixed. Vestibular system was found to be affected only minimally. The patients were then given levothyroxine and follow-up was done when they were euthyroid, which revealed statistically significant improvement in hearing threshold in 30% ears, in which conductive impairment was more common to be improved. The middle ear compliance and pressure, on impedance audiometry, also improved significantly in 50% and 87.50% ears respectively. Statistically significant change was also observed in acoustic reflex threshold. Improvement was also noted in wave I, V and interpeak (I-V) latencies, on Brain stem Evoked Response Audiometry (statistically not significant). The results of auditory investigations suggest a causal relationship between hypothyroidism and hearing loss. The site of
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