What is Tympanometry?
It is the measurement of sound getting into the ear, while the pressure on the drum is raised and lowered.
What is its use?
Tympanometry is used to look at middle ear function. ie is there fluid holding the drum stiff and non-mobile.
What do we see if the ear is normal?
A normal ear should allow the most amount of sound to get in when no pressure is applied to the drum. When +ve pressure is applied, the drum gets pushed, allowing less sound to get through. When -ve pressure is applied, the drum gets sucked, and less sound gets through again.
Therefore a normal ear gives a bel shaped curve called a TYPE A curve. All you have to know is an A curve is NORMAL.
A curve: peaks at zero pressure.
B curve is flat ie no peak
How is it relevant to my child with hearing concerns?
If a child has fluid behind the eardrum, tympanometry gives a flat curve called a B curve (no sound gest thru with +ve or -ve pressure). This is because the drum is splinted by fluid behind, and pressure makes no difference to sound getting through.
Tympanometry helps the doctors know if the fluid is affecting the child.
How do we do it?
We do the test by an instrument called a tympanometer.
It creates a sound and sends to the eardrum. A microphone is there to pick up any return sound while the pressure is applied to the drum.
What is its role in managing your child?
Tympanometer another tool we use to give the doctors all the information they need to help you. Tympanometry is only a part of a full audiometric test we do. While tympanometry does not replace a good clinical assessment, it complements and gives additional information your doctor needs to help you.