Pure tone audiometry (PTA) is the crucial method for hearing function assessment in adults. Auditory brainstem response (ABR) and auditory steady-state response (ASSR) are mainly registered in adults only if objective hearing evaluation is required, in particular in cases of expertise.
OBJECTIVE
To compare thresholds obtained by PTA and ASSR at speech frequencies; to analyze causes of possible thresholds discrepancies.
MATERIAL AND METHODS
Totally 244 patients aged from 18 to 104 were examined in two clinics. After basic ENT check-up air and bone conduction PTA at standard frequencies was run, next — ABR and ASSR registration.
RESULTS
Correlation coefficient between ASSR and PTA thresholds was 0.7—0.71 at frequencies 500—1000 Hz and 0.54—0.58 at frequencies 2000—4000 Hz. No significant difference was revealed between thresholds obtained for right and left ears and between results obtained in two clinics. The least discrepancy between PTA and ASSR thresholds (0.8—11.8 dB) was obtained at 1000 Hz, the maximum one (13.7—15.1 dB) was got at 4000 Hz. The significant strong correlation (r=0.7) between PTA and ASSR thresholds discrepancy degree at frequencies 2000 to 4000 Hz and slope audiogram type was revealed. The weak correlation between PTA and ASSR thresholds discrepancy extent and hearing loss degree and patient’s age was got.
CONCLUSION
ASSR registration reliability in adults was shown and the method could be applied in case if either PTA is not accessible or PTA results are invalid. PTA and ASSR thresholds discrepancies were revealed in patients with slope audiometry types, high frequency ASSR thresholds might be better than PTA ones.