DISEASE PAGE

Conductive / Middle-Ear Pathology

Emissions absent despite a healthy cochlea — the transmission path is blocked.

The OAE signature

  • Emissions are reduced or absent even though the outer hair cells themselves are normal.[5]
  • A flat tympanogram or conductive air–bone gap alongside an absent OAE points to the middle ear, not the cochlea.[6]
0 ms20 ms
— Normal ear— Conductive / Middle-Ear Pathology
Simulated TEOAE comparison. Educational signal model — not recorded patient data.

Audiogram companion

The pure-tone audiogram below accompanies the OAE signature. Reading the two together — what the threshold shows and what the emission shows — is the core diagnostic skill.

0204060801002505001k2k4k8kFrequency (Hz)
○ Right — PTA 43 dB (Moderate)✕ Left — PTA 43 dB (Moderate)
Pure-tone audiogram companion. dB HL increases downward, following clinical convention. Illustrative thresholds — not recorded patient data.

Why the emission looks this way

  • The middle ear must transmit the stimulus inward and the emission back outward. Effusion, ossicular disease, or a poor probe seal attenuates both directions, abolishing the recordable emission.[3]

TEACHING POINT

Always confirm middle-ear status before calling an absent OAE a cochlear problem — a conductive block produces an identical refer result.[6]

Sources for this page are listed on the References page. Browse all condition patterns from the atlas home.