Impedance Audiometry Test commonly referred to as Tympanometry or Immittance Testing—measures hearing acuity in relation to the physiological functioning of the middle ear. The procedure is effortless and straightforward, making it a preferred option in assessing fluid levels in the middle ear, perforated ear drums, Eustachian tubes not functioning properly, and problems in the ossicles among other things.

Why Ent Refer for Impedance Audiometry Test

• To assess middle ear pressure.
• To measure the mobility of the eardrum (tympanic membrane).
• To assess acoustic reflex responses involving the stapedius muscle.
• To identify pathologies within the middle ear (e.g., otitis media, osteosclerosis, etc.)

Components of the Test

• Tympanometry – Registers the movement of the eardrum as a function of changing air pressure in the ear canal.
• Acoustic Reflex Testing – Registers involuntary muscle contractions in the middle ear due to an intense sound.

What Conditions Can It Help Diagnose?

• Otitis media with effusion
• Eustachian tubes not functioning properly
• Tympanic membrane perforation
• Otosclerosis (abnormal bone growth in the middle ear)
• Ossicular disarticulation
• Facial nerve lesions affecting reflexes

How Impedance Audiometry Test Performed?

• Probe is fitted gently into the ear canal.
• A tone is given at varying air pressure by the machine.
• The response of the eardrum to these changes is then tracked.

The procedure takes no more than a couple of minutes for each ear.

Results of Tympanometry Tests (Classifications)

• Type A: Functioning middle ear of normal limits.
• Type As: Stiffer than normal middle ear system
• Type Ad: Floppier than normal middle ear system
• Type B: Flat trace indicating fluid, perforation, or both.
• Type C: Negative pressure, indicating Eustachian tube dysfunction.