Condition · Outer / middle ear

Otitis Media with Effusion

Middle-ear fluid — reflex absent on the probe side, type B tympanogram

The commonest reason a reflex is absent

An effusion loads and stiffens the middle-ear system. Because the reflex is recorded as a change in admittance, the fluid both blocks measurement on the probe side and attenuates the stimulus when the affected ear is stimulated. The accompanying tympanogram is characteristically flat (type B).

Why it matters in the cross-check

An absent reflex with a type B tympanogram and a conductive loss is fully explained by effusion; no further neural inference should be drawn until the middle ear is clear. The reflex may return once the effusion resolves.

The reflex signature

Stim. Right
Stim. Left
Probe Right
Absent
Absent
Probe Left
Elevated
110 dB HL
Present
90 dB HL
The characteristic four-cell grid for this condition.

Absent responses for the affected probe ear, with possible elevation when the affected ear is the stimulus ear because the effusion attenuates the sound.

Reflex decay

0s2s4s6s8s10s0%50%100%50% criterion
Negative (normal) decay — amplitude is well maintained across the 10-second hold. Not assessable on the affected side, since a reflex cannot be recorded through an effusion.

Pure-tone audiogram

0204060801002505001k2k4k8kFrequency (Hz)Hearing level (dB HL)
○ Right ear✕ Left ear
Right ear: mild flat conductive loss with an air–bone gap; resolves as the effusion clears.

Frequencies plotted: 250, 500, 1k, 2k, 4k, 8k Hz.

References for this page

  1. Gelfand SA (2009). Essentials of Audiology. Thieme, 3rd edition.
  2. Hall JW (2014). Introduction to Audiology Today. Pearson, Boston.
  3. Katz J (Ed.) (2015). Handbook of Clinical Audiology (7th ed.). Wolters Kluwer, Philadelphia.
Want to contrast this with another condition? The comparison tool places any two reflex signatures side by side.