Electrically Evoked Auditory Brainstem Responses in Children Fitted with Hearing Aids Prior to Cochlear Implantation

Area of Science:

• Neuroscience
• Audiology
• Pediatrics

Background:

• Sensorineural hearing loss (SNHL) in children requires timely intervention.
• Hearing aids are a common management strategy before cochlear implantation.
• The impact of hearing aid use on auditory pathway development in children with SNHL, including those with inner ear malformations (IEMs), is not fully understood.

Purpose of the Study:

• To investigate the effect of hearing aid use on peripheral auditory pathways in children with SNHL.
• To compare neurophysiological responses between children with normal inner ear structures and those with IEMs.
• To evaluate the sensitivity of different electrical stimulation sites for auditory pathway assessment.

Main Methods:

• Electrically evoked auditory brainstem response (EABR) was measured in 40 children with hearing aids.
• EABR was evoked by electrical stimulation at the round window niche (RWN) and round window membrane (RWM) during cochlear implantation.
• Onset age of hearing aid use, inner ear structure (normal vs. IEMs), and stimulation site were analyzed.

Main Results:

• Earlier hearing aid use onset significantly correlated with shorter peak latencies for wave III (eIII) and wave V (eV) in EABR.
• Higher EABR thresholds were observed for RWN stimulation compared to RWM stimulation.
• Children with IEMs exhibited higher EABR thresholds than those without IEMs.

Conclusions:

• Early hearing aid use may enhance the physiological function of peripheral auditory pathways in children with SNHL, regardless of inner ear structure.
• EABR via RWM stimulation is more sensitive for assessing auditory pathway function than RWN stimulation.
• These findings provide neurophysiological evidence supporting early hearing aid intervention for children with SNHL.