Clinical Case · Clinician

An infant with absent ABR but preserved otoacoustic emissions

Vignette

A 9-month-old has absent or grossly abnormal ABR waveforms with preserved otoacoustic emissions and cochlear microphonics — a picture consistent with auditory neuropathy spectrum disorder. A multiple-frequency ASSR is recorded and yields present responses at moderate intensities.

Audiogram

-10020406080100120500 Hz1k Hz2k Hz4k HzHearing level (dB HL)
O Right earX Left ear
Estimated thresholds by ear. O = right, X = left.

ASSR finding

ASSR yields present responses where no reliable ABR could be obtained; the ASSR-estimated thresholds differ from later behavioural thresholds, particularly at low frequencies.

Diagnostic question

How should the ASSR result be used in this child with suspected ANSD?