Clinical study on low vs high probe tone frequency tympanometry in children: Rural population

Background: Hearing impairment is a major problem worldwide, significantly delaying acquisition of speech in children. Unfortunately delayed detection of hearing impairment especially in rural and remote areas, adds a significant burden to the society and the nation. Hence early detection of hearing impairment is imperative and the need of the hour lies in developing an easy, cost effective and reliable method for testing large number of neonates and infants. This study was to assess the effectiveness and utility of Tympanometry as a screening tool for assessment of middle ear pathology in neonates and infants. Middle ear disorders are significantly prevalent in young children. Aim: Investigating and comparing the results of visual inspection of the tympanic membrane to the results of Tympanometry with traditional probe tone (226 Hz) and high frequency probe tone (678 Hz) in” ears without effusion” and “ears with effusion” and to establish their sensitivity and specificity to detect middle ear disorders as a database in clinical practice. Materials and methods: Subjects were evaluated for the stable middle ear/ Eustachian tube function. Ears with no sign of effusion in the middle ear on otoscopy were labeled as “ears without effusion” and those who showed the presence of fluid in the middle ear were labeled as “ears with effusion”. Blinded to otoscopic ear exam results, Tympanometry was conducted with conventional probe tone of 226 Hz and high probe tone 678 Hz by audiologist using standard procedure. Results: Otoscopic examination results of ears for all age groups were evaluated and ears without effusion and with effusion were tabulated. Conclusion: The tympanometric parameters obtained with 226 Hz and 678 Hz probe tones have statistically significant differences in detecting the ears without effusion and with effusion. Compliance values also proved to be statistically different with the different probe tones.