Immitanciometry or Acoustic Immitance: What is it?
Immitanciometry is a quick and easy-to-perform exam that helps evaluate the condition of the eardrum, the middle ear ossicles (maleus, incus and stapes) and the Eustachian tube (communication between the nose and ears).
It is performed with the patient sitting, inside or outside the acoustic booth (but in a quiet environment). The audiologist inserts a small tube into the patient’s ear canal to seal it completely for a short time. This probe is connected to a portable device called an immitanciometer, which analyzes two functions: 1) the complacence of the eardrum (how much it moves when it receives a certain positive or negative pressure); 2) what sound intensity can trigger a protective ear reflex, known as acoustic or stapedial reflex.
The presence of secretion in the middle ear or problems in the ossicles or in Eustachian tube may alter the results, so it is very useful test in certain cases:
1) in babies, to complement the hearing screening; 2) on suspicion of middle ear diseases; 3) in pre and postoperative routine of the ear; 4) in patients with hearing loss, tinnitus, dizziness or paralysis of the facial nerve; 5) in children who speak loudly and ask constantly to repeat sentences; 6) in patients with ear pain, respiratory allergies and / or mouth breathing