Otoacoustic Emissions (OAE)

Otoacoustic emissions are low-level sounds generated by the outer hair cells of the cochlea in response to acoustic stimulation. When the outer hair cells function normally, they amplify incoming sound and also produce a measurable echo that travels back through the middle ear and out of the ear canal, where a sensitive microphone can detect it. OAE testing is non-invasive and does not require a behavioral response, making it particularly useful for newborn hearing screening and assessment of young children.

There are two main types: transient evoked OAEs (TEOAEs), which use a brief click stimulus, and distortion product OAEs (DPOAEs), which use two simultaneous tones. Absent OAEs indicate that the outer hair cells are not functioning normally, suggesting cochlear hearing loss. However, OAEs can also be absent when there is middle ear dysfunction (such as fluid), even if the cochlea itself is intact.

OAE results are always interpreted alongside other audiological measures.