Peri-intraventricular hemorrhage: Study of the inhibitory effect of auditory efferent pathway

Abstract

Purpose: to determine the functioning of the efferent auditory system in premature newborns with intraventricular hemorrhage. Method: the sample consisted of 44 newborns, divided into two groups. The study group was composed of 22 premature newborns with intraventricular hemorrhage/and the control group was composed of 22 newborns without intraventricular hemorrhage, matched to the study group for gestational age, correct gestational age and sex. The groups were submitted to the evaluation of the inhibitory effect of auditory efferent in otoacoustic emissions (equipment ILOv6-Otodynamics Ltda®) and auditory evoked potential with and without contralateral noise (equipment SmartEP-Intelligent Hearing Systems®). Results: newborns with intraventricular hemorrhage exhibited a higher occurrence of central hearing alteration as well as a lesser occurrence of the inhibitory effect of auditory efferent in otoacoustic emissions and auditory evoked potential compared to the newborns without this condition. An association was found between central hearing alteration and a lower occurrence of inhibitory effect. Agreement was found between the inhibitory effect test on otoacoustic emissions and latency of the auditory evoked potential. Conclusion: premature newborns with intraventricular hemorrhage have a greater occurrence of functional abnormality of the afferent auditory system, which can be effectively identified through an evaluation of the inhibitory effect of auditory efferent in otoacoustic emissions evoked by a transient stimulus and latency parameter in the brainstem auditory evoked potential.