Prevalence and audiological characteristics in individuals with auditory neuropathy/auditory dys-synchrony.

The objectives of this study were to (a) estimate the prevalence of auditory dys-synchrony in Mysore, a city of one million population in Southern India and, (b) present the results of audiological testing of this clinical population as well as the relationship between these figures. A register-based study design was employed wherein the results of audiological tests of all patients who visited the Department of Audiology, All India Institute of Speech and Hearing between January 2000 and December 2003 were reviewed. Results showed that the prevalence of auditory dys-synchrony was around 1 in 183 in individuals with sensory neural hearing loss. Behavioural thresholds and speech identification scores were variable. Around 60% of the individuals had no measurable speech identification scores. There was no relation between the hearing thresholds and speech identification scores or between otoacoustic emissions and speech identification scores. These results indicate that auditory dys-synchrony is not an extremely rare disorder.