hearing aid purchase

CharlesHarney CharlesHarney at worldnet.att.net
Mon Dec 15 00:48:26 EST 1997


Dear John,

You have lots of questions.  Before commenting on hearing aid evaluation
I would urge to have an otoacoustic emissions test done on your child,
if it has not been done. Those frequencies at which emissions may be
present (either transient or distortion product testing) should not
receive amplification over what would present with an assistive
listening device such as an Phonic Ear Easy Listener FM system.  The
other advantage of emissions, if they are present in the higher
frequencies, is that changes in the amplitude (distortion products) of
the emissions may objectively signal that the hearing loss is of a
progressive nature (assumming no middle ear component is present).  Have
the child's hearing checked every 3 months for 1-2 years.

By all means have the audiologist do sound field testing on the child.
Plug up the opposite ear with earmold impression material and take
unaided and aided sound field thresholds to assess the maximum gain of
the unit. Real ear measurement at increasing input levels will allow the
audiologist to look at how the compression circuit is working, which may
make the audiologist change such parameters such as the center frequency
and the compression ratio for the high or low frequency channel. If the
hearing aid has multiple memories take advantage of them by programming
alternative selections that vary from what the audiologist thinks is the
"best". Set up an area in the house with toys spread out in front of the
child and sit behinfd the child asking to get one toy or another (have
background noise present such as recording of multitalkers, the
audiologist can tell you how you can get one). Change the programs and
see if your child responds to the identification task more consistently
with one program vs another. WRITE IT DOWN! Write down what you do and
then go back to the audiologist and continue to work together.

PS. If otoacoustic emissions are present at 2000Hz and above buy the
personal FM system. Use it in school and therapy. Buy a wireless hookup
for the TV for him. Rearrange your home to reduce ambient noise. Make
the whole family change their speaking habits (don't speak from behind,
speak one at a time, etc.)

Good luck,

Charlie





More information about the Audiolog mailing list