|
 Feedback from poor fitting ear molds can be a
problem. What can you do about feedback while you are waiting for new earmolds to be made?
When my son started having feedback problems in the middle of our vacation, an Audiologist
told me to get some Corn Huskers
Lotion (she was out of
Otoferm)
and rub a dab of it around the ear mold. It did the trick till we could get home and have
new ones made. Some parents tell me they control feedback with Lansinoh, a lanolin cream made for
breast-feeding mothers.
 Is
your audiologist using a powder mixed with water to make the ear molds? For
difficult to fit ears the silicone putty that comes in 2 parts, each a
different color, and is then mixed together has a bit less shrinkage and holds
its shape better. When this type of impression material is used, a better
fitting ear mold results. Also, the further into the canal the ear mold goes
(not just the impression, but the actual ear mold that's made from the
impression) the less feedback problems tend to occur.
For
infants, feedback is often a problem. They don't have control of their neck
muscles yet so the often end up laying on one of their hearing aids, which
causes feedback. The audiologists at our son's school, a private
oral school for the deaf that does newborn testing and serves the needs of
newborns through high school, uses an FM system contained in a unit that that
clips onto the bottom of the hearing aid. The use of the FM allows the mic on
the hearing aid to be turned off, stopping the feedback. If the child is at
home, an environmental mic can be used and placed near the child so the child
can hear environmental sounds as well as their own voice. They tell me that the
only problem they've had with this configuration is that sometimes the FM unit
rubs against the child's shoulder because babies have very short necks. When
this happens, the use of a Huggie device is helpful. A
system that uses cords to boot the device to the hearing aid is not advised due
to safety concerns.
Our
son's hearing loss is so bad and the power in his hearing aid so high that he
can't even have vents in his ear mold. They also have to use a special
super-heavy walled tubing. When he gets new earmolds I can always tell when the
lab didn't put in the special tubing (which is about half of the time) because
of feedback problems.
More
Than Meets the Ear: Understanding and Optimizing Your Child's Earmolds
by Brad
Ingrao, M.S.Ed., CCC-A. This document is a "Must Read" and includes a chart to help you
learn how long to expect your child's earmold to last before you start getting
feedback.
In
the newsgroup alt.support.hearing-loss,
this topic came up about feedback in digital in the canal hearing aids. One
answer, from Dr. Michael Ridenhour, was
interesting:
"Have your audiologist turn down the setting called "max
gain" 3 decibels. This will not diminish the amplification of the hearing
aid in any way. It reduces the "search" mode of the processor, which
is changing every time you change the shape of your ear canal by chewing or
smiling or whatever. If you still get it some, turn it down another 2 dB,
until it is gone." (You can find this message
here
on Google).
Here
are some links to other Websites with info on Feedback:
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