Development of a middle ear screening for newborns and infants

Universal newborn hearing screening (UNHS) programs typically show fail rates of about five per cent. While only a small percentage of the newborns who failed the UNHS have a permanent hearing loss, middle ear problems are much more common. The aim of a currently ongoing project is the development of a screening test of the middle ear status in newborns and infants.

The test will be based on a measurement of the acoustic input impedance of the ear in the frequency range from 500 Hz to 10 kHz. Unlike wideband tympanometry, in the new test the impedance will be measured at ambient pressure. In the current study impedance measurements are conducted on infants aged 0 to 5 month with both normal and pathological middle ear findings. The measured impedance will be used for a model-based prediction of the input impedance of the middle ear, by considering acoustical effects of the residual volume and the wall compliance of the ear canal as well. The input impedance of the middle ear could then be used to specify normative values. In addition, data of a UNHS-screening test, of 1 kHz tympanometry, of visual findings regarding outer and middle ear status and of wideband absorbance measurements under ambient and under tympanometric pressures are collected.

First measurement results show a significant influence of the compliant ear canal walls on the measured input impedance of the ear.

In contrast to commercially available wideband absorbance measurement systems, which are based on the assumption of rigid ear canal walls, in the present approach the influence of compliant ear canal walls can be taken into account.

Publication History

Publication Date:
18 April 2018 (online)