What is tympanometry?
In simple terms, tympanometry is a medical test that measures the function and movement of the
eardrum and middle ear. The results of tympanometry are represented on a graph called
a tympanogram. The test is usually quick and painless, unless the eardrum or middle ear are inflamed.
Important definitions
* Tympanometry: A test that measures the air pressure in the middle ear.
* Tympanometer: The device a clinician uses to perform a tympanometry test. There are many brands
and types.
* Tympanogram: The test results plotted on a chart.
What is a tympanometer used for?
The tympanometer causes the air pressure in your ear canal to change as you hear a low-pitched
tone. The feeling is similar to the pressure changes felt during takeoff and landing when you’re on a
plane. While the pressure is changing, measurements of your eardrum’s movement will be taken and
recorded. It is important that you are quiet and still during this test.
Why is tympanometry used?
Tympanometry is typically used to detect or rule out several things: the presence of fluid in the middle
ear, otitis media (a middle ear infection), a hole in the eardrum (perforation), or Eustachian tube
dysfunction. This test is especially important for children who have suspected middle ear problems, but
it's also sometimes given to adults as part of a routine hearing test to determine if there are any middle
ear problems contributing to hearing loss.
Adults and children who are seeking medical clearance for hearing aids will usually receive a
tympanometry test. Fluid behind the eardrum is the most common cause of an abnormal tympanogram
because it prevents the eardrum from moving and transmitting sound properly. This condition is nearly
always temporary and medically treatable.
What is a tympanogram?
A tympanogram is a graphic representation of how the eardrum moves in response to the air pressure in
the ear canal.
CLASSIFICATIONS OF TYMPANOGRAM:
TYPE: A
* Suggests normal middle ear functioning
* Peak is between +/- 100 daPa
* Compliance from 0.3-1.5 ml
TYPE : AD
* Suggests a highly compliant middle ear system
* Peak is between +/- 100 daPa
* Compliance is more than 1.5 ml
TYPE: AS
* Suggests a less compliant middle ear system
* Peak is between +/- 100 daPa
* Compliance is less than 0.3 ml
TYPE: B
* Suggests middle ear involvement from fluid (middle ear effusion)
* There is no identifiable peak
* Ear canal volume is normal
TYPE: B-HIGH
* Suggests middle ear involvement from a perforation or patent grommet
* There is no identifiable peak
* Equivalent ear canal volume exceeds normal limits; much larger than 1.5cm3
TYPE: C
* Suggests Eustachian Tube dysfunction (often seen just before or after effusion)
* Peak is below – 100 daPa
* Compliance from 0.3-1.5 ml