Comparison of 226 Hz and 1000 Hz tympanometry results in infants

Abstract

Tympanometry with a 226 Hz probe tone is a reliable indicator of middle ear disease in adults and older children. However, it is reported to produce a high rate of false-negatives in young infants. Tympanometry with a 1000 Hz probe tone has been reported to better indicate middle ear dysfunction in infants. However, age-graded norms for 1000 Hz tympanometry are currently not available. Furthermore, the results of 226 Hz and 1000 Hz tympanometry have not been compared in large numbers of infants of different ages. Tympanograms with 226 and 1000 Hz probes were analyzed from 1879 7- to 40-week-old infants to determine whether tympanometric compliance changes with age during infancy, whether 226 Hz compliance predicts 1000 Hz compliance and whether tympanometric screening results obtained with these probe frequencies agree. Preliminary results indicate that infants with 226 Hz compliance of 0.1 mmh had low 1000 Hz compliance. For infants with mean (0.3 mmh) or high (0.5 mmh) 226 Hz compliance, 1000 Hz complia...