Acoustic Reflex Testing in Neonatal Hearing Screening and Subsequent Audiological Evaluation.

Area of Science:

• Neonatal audiology
• Otoacoustic emissions
• Hearing screening

Background:

• Neonatal hearing loss affects 1-3 per 1000 live births.
• Early detection and intervention are crucial for optimal language and cognitive development.
• Risk factors for neonatal hearing loss include low birth weight and prematurity.

Purpose of the Study:

• To evaluate acoustic reflex screening and thresholds in healthy neonates and those at risk.
• To determine the impact of birth weight and gestational age on acoustic stapedial reflex (ASR).

Main Methods:

• Assessed 18 healthy neonates and 16 at-risk neonates using transient evoked otoacoustic emissions (TEOAEs).
• Conducted acoustic reflex screening and threshold tests with pure-tone and broadband noise stimuli.
• Analyzed the influence of gestational age and birth weight on ASR.

Main Results:

• Lower gestational age and birth weight were associated with reduced ASR elicitation by pure tones, particularly at 0.5, 1, and 2 kHz.
• At-risk neonates (Group II) exhibited higher ASR thresholds and absent reflexes more frequently compared to healthy neonates (Group I).
• Broadband noise elicited responses in all neonates, while pure-tone stimuli revealed significant differences between groups at 1, 2, and 4 kHz.

Conclusions:

• Birth weight and gestational age significantly influence acoustic reflex elicitation in neonates.
• Infants with risk factors like low birth weight and prematurity are less likely to exhibit ASR and have elevated thresholds.
• ASR testing, especially with broadband noise, is valuable for neonatal hearing assessment, with pure-tone results indicating higher risk in preterm or low birth weight infants.