Aural Atresia means the ear canal has failed to form and there
is no opening from the outside ear to the hearing bones. In most
cases, this congenital abnormality is present on one side only
(>80%). It is usually found more often in males and the hearing
organ is usually not affected. Repair of this condition starts
with repair of any outside ear abnormality present. This is known
as MICROTIA
and it takes several different forms. Please see Congenital
Ear Abnormalities for more information.
Repair of the missing ear canal involves several steps. First,
your child will be given a “grade” that will allow
your doctor to tell you if your child is a candidate for surgery
and the approximate chances for hearing return.
Generally, if your child is a surgical candidate, approximately
2/3 of the time, hearing can be improved to the 30-35dB range.
Approximately 50% of the time, hearing can be improved to the
25dB range (just outside normal). Most children have a maximum
conductive hearing loss to start meaning they hear = 50dB.
The “grade” your child gets is determined partly
from a CT scan (X-ray study) of the ear. This scan is usually
done about 4-5 years of age. It does not help to get scans earlier
because, growth, to some extent will affect the outcome.
Once the patient is found to be a candidate, your doctor will
review the CT scan with you and go over the surgical repair in
detail.
Surgery consists of making an incision behind the ear and creating
an ear canal in the bone with a drill. The ear bones are uncovered
and a new ear drum is made from tissue under the skin behind the
ear. A skin graft (usually from the hip) is then used to make
the new ear canal skin. Finally, an opening is made in the outside
ear itself. This will look large at first because there is some
expected shrinkage. This surgery takes about 4 hours.
About 10 days after surgery, packing is removed from the ear.
You should be prepared that minor revision surgery is sometimes
necessary in the first 6months to a year due to scar formation
or narrowing of the ear canal opening.
Patients usually stay overnight and are discharged the following
morning. Regular follow-up is crucial to the success of the operation.
Therefore, if you cannot commit to regular visits as directed
by your doctor, it is best not to start the process initially.
Success of this operation is measured primarily by the hearing
result and it outlined above.
Complications of this procedure include: bleeding, wound infection,
loss of graft, infection or scaring at graft site, failure to
achieve expected hearing result and hearing loss. Your doctor
will discuss these possible complications with you before surgery.