Auditory brainstem response in premature infants with very low birthweight

Background: Premature infants with very low birthweight (VLBW) differ from the full term ones in the innate, environmental factors and the health. These differences probably result in a developmental change on auditory pathway. In this article, we compared the auditory brainstem response (ABR) of VLBW premature infants with those of the full term in order to investigate the developmental difference of auditory pathway between the two populations. Methods: ABR was performed on 72 six-month-old VLBW premature infants and 65 twelve-month-old premature infants. Ten six-month-old and eight twelve- month-old age-matched full term infants were tested as control group. Latency (L) and interpeak interval (IPI) of ABR were analyzed. Results: The L I in six-month-old VLBW premature infants was longer than that in the full term infants (1.539 msec vs 1.478 msec). The L I in twelve-month-old VLBW premature infants was also longer than that in the full term ones (1.506 msec vs 1.448 msec). There was no difference in L III and L V between the two groups. The IPI I - III in six-month-old VLBW premature infants was shorter than that in the full term infants (2.664 msec vs 2.766 msec). The IPI I - III in twelve-month-old VLBW premature infants was shorter than that in the full term ones (2.542 msec vs 2.609 msec). There was no difference in IPI III - V between the two groups. The IPI I - V in twelve-month-old VLBW premature infants was shorter than that in the full term infants (4.663 msec vs 4.768 msec), while no difference was noted in the six-month-old group. Conclusions: L I was longer and IPI I III was shorter in VLBW premature infants than those in the full term infants. We considered that the prolongation of L I might be due to the higher incidence of otitis media in the VLBW premature infants. Longer extrauterine life duration of the VLBW premature infants might contribute to the shortness of IPI I - III.