Abstract Abstract 165
The present study aimed to investigate the effect of intrauterine growth retardation on the maturation of the peripheral auditory organs by means of Click Evoked OtoAcoustic Emissions (CEOAE). CEOAE are sounds, measured in the external ear canal, produced by the motile activity of the outer hair cells in the organ of Corti. The response level of these CEOAE is known to increase in preterm infants during the period from 30 to 40 weeks Post Conceptional Age (PCA). In a matched control study we compared the CEOAE amplitude of 23 ears of 12 SGA infants with Appropriate for Gestational Age (AGA) infants, matched on PCA at test date. The median birthweight of the SGA infants was 1768 g (range 780-2580 g) at a median gestational age at birth of 37.1 weeks(range 29.4-41.4 weeks). For the AGA infants, the median birthweight was 2398 g (range 1280-3330 g) at a median gestational age of 35.9 weeks (range 29.0-41.4 weeks). In the left ears, the CEOAE amplitude was significantly lower in SGA infants than in AGA infants (Wilcoxon, median amplitude SGA=15.1 dBSPL, median amplitude AGA=20.3 dBSPL, n=12, p<0.05). In the right ears, there proved to be a similar trend (Wilcoxon, median amplitude SGA=18.5 dBSPL, median amplitude AGA=23.4 dBSPL, n=11, p=0.13). Compared to the normal course of maturation of CEOAE amplitude in preterm infants, SGA infants indeed showed a trend of delayed maturation of cochlear activity and/or the middle ear transmission. The effect of this delayed maturation on the long-term auditory integrity in SGA infants remains to be studied.
