FV 183. Comparison of the Early Auditory Evoked Potentials during the First Month of Life in Term and Preterm Children

Background: The sense of hearing is crucial for a normal cognitive and social development in children. Early brain stem auditory evoked potentials are a neurophysiological test that provides functional information about the integrity of the auditory system and in addition viability of the brain stem. Hearing deficits should be detected early in life to support the child adequately and to avoid a delay in language development.

Aim: The primary aim of the study was to detect the effect of prematurity on the maturation of the auditory system. A secondary aim was to determine if the birth weight and the gender of the infants have any impact on the maturation of the auditory system as well.

Research Question: How does prematurity, birth weight, and gender affect the maturation of the auditory system in infancy?

Methods: To answer the question, a retrospective study was conducted. A total of 85 infants were included in the study. Fifty-five preterm infants born earlier than or at 37 weeks of gestational age and 30 term infants born later than 37 weeks of gestational age constituted the study groups. Subgroup analysis was conducted for birth weight, gender, and neonatal history.

For many years, a standard AEP recording protocol is being used at the Children’s hospital of Eastern Switzerland to examine the children. The examination is conducted at the age of 39 to 42 weeks (PCA). The recoding is performed during sleep either prior breast feeding or with sleep induction by melatonin. To record the electric activity of the hearing nerve and brain stem, four electrodes were placed on the child head, with the active electrode on the ipsilateral mastoid. The ears were stimulated by sequential unilateral click noises with 60 and 30 dB. An average of the electric activity after 1,500 acoustic stimulations (click sounds) was recorded. During the first 10 milliseconds of recording, the potentials from the hearing nerve and brain stem were localized and the latencies were determined. The latencies were compared between the groups using t-tests or Mann–Whintey’s U test, whenever more appropriate.

Results: The comparison of the brain stem–related potentials (wave V) and latencies at 60 dB revealed a significant difference between full-term and premature infants (mean difference: 0.76; 95% confidence interval: 0.5040–1.0159; p <0.001). No difference for the subgroup analysis of gender and birth weight was found. However, some diseases in the neonatal period clearly lead to a disturbance of the maturation of the auditory system but due to a large heterogeneity statistical comparison is difficult.

Conclusion: AEP are a valuable tool to assess the integrity of the auditory system in infants and children at risk which can be detected early in life.

No conflict of interest has been declared by the author(s).