Impedance Audiometry

The primary purpose of impedance audiometry is to determine the status of the tympanic membrane and middle ear via tympanometry. The secondary purpose of this test is to evaluate acoustic reflex pathways, which include cranial nerves (CN) VII and VIII and the auditory brainstem.

This is an objective test of Hearing. Term Impedance means the ‘opposition’. This test measures Opposition offered by the middle ear system in the flow of acoustic / Sound energy. This test help in assessing Ear Drum Mobility with the negative and Positive Pressure variation, Ear canal Volume and Stapedial Reflexes.

This test is completed in the Two Steps

1. Tympanometry – this tests the Ear drum mobility and shows results in the form of Graphical Representation called Tympanogram. This Tympanogram Tells about the Possible Cause of Middle Ear Pathology (Example- Early / Late Stages of Chronic Supporative Otitis Media, Perforation of Ear Drum, Otosclerosis Etc.)

2. Acoustic Reflexes- This test assesses the Neural Pathway (Ipsilateral and Contralateral Pathways).

Impedance Audiometry helps in finding about the Movements of Ear Drum, Eustachian Tube Function, identifying about status of ossicular chain, presence of Fluid inside Middle ear, Facial Nerve integrity.