Functional abnormality of the auditory brainstem in high-risk late preterm infants

ObjectiveTo examine whether late preterm infants with perinatal problems are at risk of brainstem auditory impairment.Methods68 high-risk late preterm infants (gestation 33–36 weeks) with perinatal problems or conditions were studied at term using maximum length sequence brainstem auditory evoked response. The controls were 41 normal term infants and 37 low-risk late preterm infants.ResultsCompared with normal term infants, the high-risk late preterm infants demonstrated a significant abnormal increase in MLS BAER variables that mainly reflect more central function of the brainstem auditory pathway, including wave V latency, III–V and I–V interpeak intervals, and III–V/I–III interval ratio. The abnormalities were more significant at higher than at lower click rates. The slopes of MLS BAER-rate function for these variables were increased. Compared with low-risk late preterm infants, the high-risk infants showed similar, though slightly less significant, abnormalities, mainly a significant increase in III–V and I–V intervals.ConclusionsMaximum length sequence brainstem auditory evoked response components that mainly reflect central function of the auditory brainstem were abnormal at term in high-risk late preterm infants.SignificanceMore central regions of the auditory brainstem are impaired in high-risk late preterm infants, which is mainly caused by associated perinatal problems or conditions.

► Little is known bout whether high-risk late preterm infants has brainstem impairment. ► Maximum length sequence brainstem auditory evoked response was found to be abnormal in these infants. ► This suggests that more central regions of the auditory brainstem are impaired in high-risk late preterm infants.