Auditory Steady-State Response for Bone in Infants without Hearing Loss

Introduction: Auditory steady-state response (ASSR) for bone conduction contributes to the early diagnosis of hearing loss, because it is an electrophysiological procedure that can predict auditory thresholds.

Objective: To analyze the thresholds obtained in the study of bone conduction ASSR in normal hearing infants born at term.

Methods: Cross-sectional and contemporary study in which 32 infants were evaluated, of both genders, term infants, mean age 4.2 ± 1.4 months. The infants showed otoacoustic emissions, tympanometry unchanged, acoustic reflexes, and appropriate otorhinolaryngology test. Reviews were then conducted by the ASSR bone conduction at frequencies of 500, 1,000, 2,000, and 4,000 Hz. Comparisons between gender and evaluation of the association between ages were also performed.

Results: When comparing the ASSR frequencies from 500 Hz to 4,000 Hz in the right ear, there was a significant difference, with the frequency of 500 Hz showing higher values (F = 51.9, df = 29.3, p < 0.001). Regarding gender and age, there was no significant association between the ASSR in the frequencies used, 500 Hz (r = −0.024, p = 0.898), 1,000 Hz (r = −0.017, p = 0.927), 2,000 Hz (r = 0.203, p = 0.265), and 4,000 Hz (r = −0.026, p = 0.887).

Conclusion: There was significant difference between the thresholds obtained with the ASSR at frequencies of 500 Hz to 4,000 Hz only in the right ear, where thresholds showed higher values at frequencies of 500 Hz. There was no statistically significant association between the results of ASSR with age and gender of the infant.

Keywords: Auditory, auditory steady-state response, hearing infants, electrophysiology, auditory perception.