OPTIONS TO IMPROVE HEARING FOR PEOPLE WITH
Bone Anchored Hearing Aids (BAHA's)
A hearing device attached to a fixing that is implanted in the skull.
It involves a small surgical procedure to put the fixing in. There
is no in-the-ear component for the BAHA system and therefore it
is suitable for people with aural atresia (no ear canals). The BAHA
system does not magnify or reproduce sound, but rather conducts
the natural sound one hears through the skull to the functioning
cochlea, bypassing the malfunctioning ear canals and middle ear
structures The BAHA system is the only implanted treatment that
works through direct bone conduction and therefore, clearly stands
apart from any hearing aid available, eg, ear canals and middle
ear structures. This osseointegrated implant provides an alternative
method for sound via the skull bone, much like a cochlear implant
offers an alternative method for sound through the cochlea. The
BAHA system replaces ear canals, which are absent due to birth defects.
Babies born with born bilateral atresia can wear a Softband Baha
which is the BAHA worn on a headband. When they are older and
the skull is thicker they can be fitted with a BAHA, which is
attached to a fixing in the skull. It involves a small surgical
procedure to put the fixing in. This BAHA gives a better quality
sound than a BAHA worn on a headband.
This system is also successfully used for people with unilateral
Bone Conduction Hearing Aids
This is also an option for children with bilateral atresia. The
traditional type hearing aids can be worn on a headband.
In the hands of a highly specialised experienced surgeon, reconstructing
the ear canal and restoring the natural hearing is a realistic possibility.
Atresia repair involves the drilling out of bone where the ear canal
should be, lining it with skin grafts and the creation of an ear
drum. The goal of surgery is to create a healthy and hearing ear.
Not all people with atresia are candidates for the surgery and a
CT scan is needed to evaluate whether or not this surgery can be
Operating on a patient with atresia is challenging.
Years ago attempts to reconstruct the ear canal resulted in poor
hearing improvement and various complications. However, in the past
50 years, improvements in surgical technology, such as the operating
microscope and the facial nerve monitor, have resulted in good surgical
success rates for properly chosen patients. It is very important
that only a surgeon who specialises in this surgery and who has
a proven track record in this procedure is used.
If atresia repair surgery is successful, patients
with unilateral atresia should be able to listen to stereo music,
tell the directionality of sound, and hear better in a noisy environment.
In a quiet place or in one-to-one conversation, patients are told
not to expect improved hearing after surgery. With bilateral atresia
repair, successful surgery can give improvements in all of the above.
Atresia repair is currently not available in
Ireland and patients from Ireland have travelled to the USA for
this procedure. The surgeons best known for their work in this area
include Dr Joseph Roberson at The California Ear Institute in Palo
Alto, California, USA and Dr Bradley Kesser,Virginia, USA.