Delay in the development of the auditory pathways. A differential diagnosis in hearing impairment in young infants

Background. Due to the increased frequency of screening tests in new-born infants, the number of subsequent examinations of very young children has increased in the Departments of Phoniatrics and Pediatric Audiology. To exclude hearing loss in young children, click stimulated brain-stem evoked response audiometry (BERA) and otoacoustic emission tests are, in general, considered to be reliable methods. However, pathologic BERA thresholds and pathologic hearing reactions have been observed occasionally in young infants who show improved and even normal hearing reactions in subjective and objective hearing tests after some months. Patients and results. Our group of 14 children (ten female, four male) was initially examined by BERA at the ages of 17 months. Twelve children had an elevated risk of hearing loss due to complications in the pre-, peri- and postnatal period. In the BERA, no deafness was diagnosed, but in all children at least monaural pathologic BERA thresholds were observed. Subjective hearing tests confirmed hearing loss. Objective and even subjective hearing reactions improved and normalised within a few months at least monaurally. Conclusion. In very young infants, the possibility of a delayed maturation of the auditory pathways must be considered when a hearing loss is diagnosed. Our examples prove that young children with sensorineural hearing loss need more than one objective hearing examination during the first year of life.