A Cochlear Implant is an electronic device that can be surgically introduced to the inner of a deaf patient to restore hearing. The Nucleus™ device is an Australian cochlear implant developed from the work of Professor Graeme Clark at the University of Melbourne. It is widely considered the best cochlear implant device available in the world for both children and adults.
The best age for a child born deaf to receive an implant is prior to the age of 2 years. This gives the best opportunity to develop normal speech and language. Adults becoming deaf with disease or injury should be implanted as soon as the diagnosis is confirmed.
An extensive pre-operative assessment is necessary to determine a patient’s suitability for the operation and this includes some or all of the surgeon, audiologist, radiologist, speech pathologist, paediatrician, geneticist, psychologist and anaesthetist.
REASONS FOR SURGERY:
Dr. Wallace recommends a cochlear implant for the following reasons:
- Congenital (from birth) severe to profound nerve deafness
- Bilateral severe to profound deafness from disease or injury
RISKS OF SURGERY:
This surgery is associated with a low risk of complication.
The specific risks of a cochlear implant operation of which you should be aware are:
- Dizziness or vertigo. This is normal for a day or two after surgery. Prolonged symptoms are rare.
- Tinnitus or spontaneous noise in the ear. Commonly present but rarely exacerbated by the surgery.
- Facial nerve injury. This is very rare. The pre-operative scan helps locate any abnormal facial nerve position.
- Taste disturbance. This is not uncommon but is almost always transient
- Meningitis. The risk of this rare complication is minimized by good surgical technique and prophylactic antibiotic.
Dr Wallace performs this operation with the patient under a General Anaesthetic, being asleep for approximately 2 to 3 hours. This is followed by about 45 minutes in Recovery.
Dr Wallace performs the surgery through an incision behind the ear using an ‘operating microscope’. Normally, no shaving of hair is necessary. The bone of the mastoid is drilled away to approach the cochlea and a bed is created in the skull bone for the body of the implant. The ‘tail’ of electrodes is inserted into the cochlea through a 1mm drill hole that is carefully sealed. The implant is tethered to the bone and the incision closed, usually with dissolving stitches. A large wrap-around head dressing is applied.
Most patients will stay in hospital for two nights after surgery for observation and prophylactic antibiotic. Any requirement for pain relief is usually minimal. Dr. Wallace books a first review in the office one week after surgery.
The main precaution after cochlear implant surgery is to avoid any chance of infection getting to the implant. Swimming should be avoided for two weeks and any heavy head colds should be treated with a broad-spectrum antibiotic. Strenuous physical exercise in the first two weeks carries a risk of disrupting the tissue seal around the electrodes and allowing in some infection and so this should also be avoided.
The hearing of sound does not happen until the Audiologist switches on the device some 2 weeks after surgery. This requires the wearing of the external components of the implant and having each individual electrode tuned or ‘mapped’. There follows an extended period of learning to get the best out of the implant.
A cochlear implant has a very high probability of giving a deaf child normal speech and language communication and restoring close to normal hearing in a deafened adult. The quality of sound is not as good as that perceived by healthy ears but advancing technology is bringing this goal very close to reality.
"Dear Dr Wallace,
Thought I would let you know how I am progressing. Thank you for your letter about listening to music and words.Marvellous! My first go at it was 10pm(late) and afterwards,we switched to Late Night News and I discovered I was hearing the news and not reading it. Also, I have seen Suzanne, my Audiologist, and am now trying a new programme not quite so much like ’Bugs Bunny’. Can hear my little grandchildren speaking to me and understand what they are saying. And get this one: This morning I heard a flock of pidgeons fly over - their wings!
Once again, thank you.