OPTIONS TO IMPROVE HEARING FOR PEOPLE WITH AURAL ATRESIA

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.

Bilateral Atresia:
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.

Unilateral Atresia:
This system is also successfully used for people with unilateral atresia.

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.

Atresia Repair
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 done.

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.