Auditory brain stem response and auditory steady state response in infants who failed hearing screening

Objective　To evaluate the effect and advantages of auditory brain stem response (ABR) and auditory steady state response (ASSR) as a measure of the auditory diagnosis in infants who failed hearing screening. Methods　Seventy infants failed hearing screening of distortion product otoacoustic emission received routine audiological evaluations and analyses including ABR and ASSR. Results　Among 70 infants (140 ears), thirty-seven ears were found to be normal, and 18 ears were mild hearing loss, twenty-one ears were moderate hearing loss, thirty-one ears were severe hearing loss and 33 ears were profound hearing loss by ABR. Linear positive correlation was found between ABR threshold and the ASSR threshold at 2 kHz and 4 kHz (IP/I0.05). But not between ABR threshold and the ASSR threshold at 0.5 kHz and 1 kHz(IP/I0.05), The rates of ASSR threshold detected at 0.5 kHz, 1 kHz, 2 kHz and 4 kHz in infants with profound hearing loss were 42.4%, 57.6%, 45.5% and 48.5% respectively, higher than that of ABR threshold (I/Isup2/sup=9.7408，IP/I=0.0450). Conclusion　There was significant relationship between ASSR at high carrier frequency and ABR in infants who failed hearing screening, and ASSR may serve as a preferable objective measure for assessing the hearing threshold with frequency speciality and high detectability in infants with profound hearing loss.