We go to Buffalo tomorrow for Nolan's repeat hearing test. Hopefully the most recent loss of hearing was due to the wax in his ears. Kids with hearing aids for a sensorineural loss rely on a healthy middle ear to maintain reasonable aided hearing levels. Nolan has a relatively mild loss, but middle ear problems can cause his hearing to drop into the severe range across all frequencies. This is the primary reason our ENT wants to get those adenoids and tonsils out.
With every hearing test, our audiologist runs a tympanogram. This measures the mobility of the eardrum and can give an indicator of middle ear health. A nice, healthy middle ear gives a "Type A" tympanogram, with a nice peak to indicate the eardrum is functioning properly. I actually only have one tympanogram with this configuration- this example is from Nolan's right ear during a relatively fluid-free period of time. This was also shortly after his second PE tube fell out of the right ear.
The second type of Tympanogram is a "Type B," and is flat. This can mean fluid, or a perforation. When Nolan's right ear dropped to a hearing level of 80dB in December 2008, his tympanogram looked like this:
Not all "Type B" tympanograms are bad. Nolan's healthy left ear always displays a "Type B" tympanogram, because it has an intact PE tube. A child with a PE tube will display a flat tymp. with a large Ear Volume. The volume lets us know that the tube is in place and functioning as it should. The tympanogram is a good way of checking up on the status of his tubes:
Hopefully our hearing test tomorrow will show a return to our June 2009 hearing levels. If we see a decline in hearing ability, a tympanogram will be run again to verify a healthy middle ear.
I have my fingers crossed for good hearing levels and a nice "Type A" tympanogram!