Comparison of threshold estimation in infants with hearing loss or normal hearing using auditory steady-state response evoked by narrow band CE-chirps and auditory brainstem response evoked by tone pips.

OBJECTIVE

The objective of this study is to compare air-conduction thresholds obtained with ASSR evoked by narrow band (NB) CE-chirps and ABR evoked by tone pips (tpABR) in infants with various degrees of hearing loss.

DESIGN

Thresholds were measured at 500, 1000, 2000 and 4000 Hz. Data on each participant were collected at the same day.

STUDY SAMPLE: Sixty-seven infants aged 4 d to 22 months (median age = 96 days), resulting in 57, 52, 87 and 56 ears for 500, 1000, 2000 and 4000 Hz, respectively.

RESULTS

Statistical analysis was performed for ears with hearing loss (HL) and showed a very strong correlation between tpABR and ASSR evoked by NB CE-chirps: 0.90 (n = 28), 0.90 (n = 28), 0.96 (n = 42) and 0.95 (n = 30) for 500, 1000, 2000 and 4000 Hz, respectively. At these frequencies, the mean difference between tpABR and ASSR was -3.6 dB (± 7.0), -5.2 dB (± 7.3), -3.9 dB (± 5.2) and -5.2 dB (± 4.7). Linear regression analysis indicated that the relationship was not influenced by the degree of hearing loss.

CONCLUSION

We propose that dB nHL to dB eHL correction values for ASSR evoked by NB CE-chirps should be 5 dB lower than values used for tpABR.