Disease Atlas

Tympanometric signatures of the conditions most often discussed in immittance teaching. Each page pairs the tympanogram with its acoustic reflex pattern and the expected audiometric picture.

Otitis media with effusion

A flat (type B) trace with a normal equivalent ear-canal volume — the hallmark of fluid loading the middle-ear system.

Type BReflex: absentDecay: n/a

Tympanic membrane perforation

A flat trace with an abnormally LARGE equivalent ear-canal volume, because the probe now measures canal plus middle-ear space.

Type BReflex: absentDecay: n/a

Eustachian tube dysfunction

A peak shifted markedly into negative pressure (type C), reflecting under-aeration of the middle-ear cleft.

Type CReflex: presentDecay: negative

Otosclerosis (stapes fixation)

A shallow (type As) peak at normal pressure. Reflexes are often absent; early disease may show a biphasic on–off pattern.

Type AsReflex: absentDecay: n/a

Ossicular chain discontinuity

An abnormally deep (type Ad) peak from a hypermobile system, classically with a large conductive air–bone gap.

Type AdReflex: absentDecay: n/a

Retrocochlear lesion (e.g. vestibular schwannoma)

A normal type A tympanogram — but with elevated or absent reflexes and POSITIVE reflex decay on the affected side.

Type AReflex: elevatedDecay: positive