RESUMO
INTRODUCTION: Impedance audiometry is a routine test for diagnosing hearing disorders in children. Typically, tympanometry uses a 220 or 226 Hz probe tone. However, using a 1000 Hz test tone is becoming increasingly popular, particularly in newborns, since it enables one to assess individual components of the ear's admittance. AIM: This study compares tympanograms for test frequencies of 226 Hz and 1000 Hz in newborns and evaluate the rate of occurrence of each type of tympanogram for both frequencies. MATERIAL AND METHOD: The study material was 53 newborns. All newborns underwent middle ear susceptibility testing at two measurement frequencies: 226 Hz and 1000 Hz. The parameters obtained with both frequencies were compared, and the utility of the 1000 Hz test frequency for middle ear diagnostics in newborns was evaluated. RESULTS: The results show that tympanograms obtained from the same ear using different test frequencies are significantly different. The 1000 Hz tone produced a higher rate of type B tympanograms (flat). CONCLUSIONS: Tympanometry curves for 226 Hz and 1000 Hz are different, and in newborns the 1000 Hz test tone revealed a higher rate of middle ear pathology. However, further studies are required to verify that 1000 Hz tympanometry is a high-sensitivity diagnostic method for middle ear problems in newborns.
