The Cochlear Implant
The cochlear implant is technically a hearing aid. It is normally used in situations of severe hearing impairment and/or in situations where the speech discrimination obtained from a hearing aid is poor. If you are a hearing impaired person wearing hearing aids but still struggle significantly with communication then there is some prospect a Cochlear Implant may provide you with benefit.
The boundaries of its fitting range are always expanding and the technology is becoming smaller and more cosmetic. ACE Audiology Melbourne refers individuals to the appropriate medical specialists when it is deemed that better benefit can potentially be obtained with a cochlear implant rather than persisting with a hearing aid.
The first step requires you to have a current hearing test result as well as data on the performance of your current hearing aids and importantly your speech discrimination ability on standardised tests. Your current hearing aids must be optimised to your current hearing loss and ACE Audiology Melbourne is happy to assist you in this regard.
Many factors are balanced in the decision to proceed with a cochlear implant. Audiology is critical but so too are the medical and radiological investigations to support surgery decisions. Although your hearing loss is a good predictor of your speech discrimination ability, this is not always the case, and a speech test in quiet and noise is important to complete. In general, a speech score under 50% tips the greater benefit in favour of a cochlear implant.
How does a Cochlear Implant Work?
The Cochlear Implant relies on the simple principles that the cochlea is “tonotopically” organised with the pitch being perceived having a physical location, and, that despite the sensory tissue being severely damaged, the underlying nerve remains intact and will respond to electrical stimulation.
Hence an electrode array is inserted into the cochlear and spirals around its full length so that it may reach as many nerve endings as possible. The externally worn equipment, takes sound from the environment and converts it to an electrode address and passes the instruction across the skin via the induction coil, which also supplies power for the implant to operate.
Naturally there is a lot of programming required to optimise the electrical stimulus for the individual. Comprehension of speech gradually improves with this fine tuning and aural rehabilitation training provided by the Audiologist managing the implant.
Who can benefit from a Cochlear Implant?
Individuals who receive marginal benefit from hearing aids due to poor speech discrimination ability, usually less than a 50% score on standardised tests, are likely candidates for a cochlear implant. It is quite common for a person with hearing loss to continue to wear a hearing aid in their better ear and compliment that with a cochlear implant in the other ear.
Often, individuals who have had severe Meniere’s Syndrome, have poorer speech discrimination in one or other of their ears than would be the case if their hearing loss was due to another pathology and of a similar severity. They do very well with a mixture of hearing aid and cochlear implant and have greater satisfaction in communication and enjoyment of life.
Other individuals may have had a total hearing loss in one ear and find hearing in noise and localising the origin of a sound to be difficult. They can be assisted with a cochlear implant for their single sided deafness.
Am I suitable for a Cochlear Implant?
This question is best answered by visiting your audiologist and having a Cochlear Implant evaluation, particularly relevant if you receive little benefit from hearing aids. ACE Audiology Melbourne is happy to perform your hearing test and advise you if a referral for a cochlear implant is appropriate in your situation.