Treatment options for hearing loss in patients with microtia atresia
When can my child's hearing be surgically corrected?
When your child is five years of age or older he or she can be further evaluated for either a canalplasty (opening the ear canal), or changing the soft band for an abutment or an implanted magnet (to hold the sound amplification device against your child's head rather than the softband). It is important that your child's otologist and microtia surgeon work together on the proper timing of surgery. Most plastic surgeons will not promote canalplasty because of the negative consequences on the quality of the ear reconstruction (I am sure you have seen photos of a fairly nice outer ear reconstructions with a large distracting hole drilled through the center of the framework for the canal).
If you are interested in canalplasty for your child, surgeons who use rib graft need to complete the ear reconstruction first before the canalplasty so that scars will not get in their way. Most medpor surgeons on the other hand are very cognisant of the increased risk of infection of the implant with secondary canalplasty so they will want you to have the canalplasty first and the outer ear reconstruction second.
Dr. Griffiths is unique and unlike other microtia surgeons, your child can have his or her hearing restoration surgery at the same time as the outer ear reconstruction (One-Stage Microtia Atresia Reconstruction). While Dr. Griffiths is carving and assembling the ear framework (whether it be out of rib cartilage or Medpor), our otologist can reconstruct their ear canal, or place a hearing device abutment or magnet at the same time. Combining the two procedures at the same time produces better aesthetics, and lower risk for canal stenosis.
Here is a close up photo of a patient who had one surgery to reconstruct her right ear and ear canal. Notice that unlike other photos that you may have seen from other surgeons after canalplasty, her ear canal is nicely positioned behind the tragus and under the crux of the helix.
How is the ear canal reconstructed?
The ear canal is reconstructed with an operation performed by an Otologist (a specialty trained ENT surgeon) called a canalplasty. As mentioned above, these patients must be carefully screened with a preoperative temporal bone CT scan and a special audiogram to determine if they are candidates for a canalplasty. The basic goal of the operation is to create a canal through the temporal bone to expose the middle ear space which contains the small bones that normally conduct the sound from the eardrum (tympanic membrane) to the oval window of the cochlea. A thin graft of fascia is harvested from the temporal muscle and is used to create the tympanic membrane. Skin grafts are then harvested to line the walls of the new canal. Dr Griffiths then connects the skin grafts to the rest of the reconstructed ear including the conchal bowl and tragus (the small bump of cartilage that is in front of the ear canal at the edge of the cheek.
What is canal stenosis and how can it be prevented?
After the ear canal is reconstructed there is a risk that it can contract and close up again (stenosis). Some authors place this risk between 50 and 60%. Dr. Griffiths and our otologist have modified the operation and the postoperative care protocol to reduce our risk to below 10%.
Can a bone conducting abutment or magnet be placed at the same time as the microtia surgery?
Yes it can! If you or your child are not a candidate for a canalplasty you can have the option of having a bone conducting hearing device abutment or magnet placed by our Otologist at the same time that Dr. Griffiths performs his one stage reconstruction of the outer ear. You will have the opportunity to meet with our Otologist before your surgery so you can review hearing device options and choose the one that best suits your needs.
What are my options for bone conducting hearing devices?
- Baha connect system. The connect system uses a titanium implant that is implanted into the skull bone behind the ear with an abutment that protrudes through the skin. The sound processor then attaches to the abutment.
- Baha attract system. The attract system uses a magnetic implant that is placed under the scalp behind the ear. The sound processor then magnetically adheres to the scalp.
Oticon Medical Pronto Pro
The Pronto Pro sound processor uses a titanium implant placed in the skull bone behind the ear. An abutment then protrudes through the scalp. The sound processor then snaps onto the abutment.
Medtronic Sophono Alpha 2 MPO
The Sophono sound processor is an abutment free attract system. Two small magnets are surgically placed in the skull bone behind the ear under the scalp. The sound processor then magnetically adheres to the scalp without an abutment.
Patients who choose the Cochlear connect system or the Oticon Pronto Pro might be candidates to have the abutment placed at the same time that their ear is reconstructed and the titanium implant placed in the skull bone behind the ear. Others will need a second simple procedure to place the abutment 3 to 6 months later by a qualified physician close to their home town. Our Otologist will recommend which will be best for you.
All three sound processor options will require programming to you or your child’s specific decibel hearing deficiency by a qualified audiologist close to your home town. We will help make arrangements for this service prior to your surgery.
“My son is experiencing a happiness and a confidence that I have never seen before. You have taken away a big, big hurt...Thank you for making my son happy.” Michael, Father of a Former Patient