CLINICAL CASE 2 OF 8

Validating a baby's first hearing aids

Vignette

A 7-month-old with bilateral moderate-to-severe sensorineural hearing loss has just been fitted with hearing aids. The family wants to know the aids are actually helping. The baby is settled and alert. You record free-field cortical responses to the speech tokens /m/, /g/ and /t/, unaided and then aided.

Findings

0100200300400latency (ms)Unaided /t/Aided /t/
No cortical response to the unaided high-frequency /t/ token; a clear response once the hearing aid is in place.

Diagnostic question

Aided cortical responses are present to /m/ and /g/ but the aided /t/ response is the one shown above. What does the aided /t/ result indicate?

References