Cochlear Implants

What is a cochlear implant? A cochlear implant is a surgically implanted electronic device that provides a sense of sound. It is often referred to as a bionic ear.

How does a cochlear implant work? In normal ears, sound waves are converted to electrical signals by parts of the inner ear. These signals are sent to the brain, where they are interpreted as sound. A cochlear implant simulates that process. It converts the sound to electrical impulses that are sent to the brain by the auditory nerve. The implant, supplemented with therapy, can assist people to recognize sounds and even speech.

Will a cochlear implant restore normal hearing? No, a cochlear implant does not restore normal hearing. It is a prosthetic substitute.  

Are cochlear implants experimental devices? No. Cochlear implant devices have been used since the 1970. They are approved by the Food and Drug Administration (FDA) in the USA for use in children and adults. 

Are there risks in cochlear implant surgery? Risk is inherent to any surgery requiring general anaesthesia. Risks specific to cochlear implants surgery are related to associated important structures in the surgical area. Complications are however uncommon.

Who is a candidate for a cochlear implant?
In profoundly deaf infants or children, if the hearing aid is not providing a progression in speech or language development.
In adults:
Severe to profound sensori-neural hearing impairment in both ears.
A functioning auditory nerve
Not benefitting enough from hearing aids
No medical reason to avoid surgery
Living in or wanting to live in the “hearing world”
Have realistic expectations about results and good support of family and appropriate access to post-cochlear implant aural rehabilitation.

What are the symptoms of hearing loss in infancy? The child will not babble or make sounds or the babbling may regress at 6 months. Normal hearing children will respond to a loud sound, while children that are profoundly deaf will not respond.

Is there a way of detecting hearing loss in babies? The recommendation is to have the infant tested at birth to screen for any hearing problems. This can be done while the child is still in the hospital. The test is called an Oto Acoustic Emission. Repeated testing should be done at least once a year to make sure that the child does not lose hearing after birth, which does occur.

What are the percentages of children born with hearing problems? Approximately 1 in 1,000 children are born profoundly deaf.

What are the options once an infant has been diagnosed as being profoundly deaf and a cochlear implant candidate? There are schools of thought that advocate non implantation. The belief is that these children should learn sign language and be part of the “deaf culture”.
Others believe that children that are born deaf should be given the opportunity to hear sound and learn language and speech through hearing.
There are advantages and disadvantages to both approaches. However, it is being recognised that the long term benefits of implantation FAR outweigh the challenges. This INCLUDES cost. In most countries it is now recognised as best practice.

What is the cost? The cost is up to R300 000.00 per ear. Most medical aids to not cover this.

Are both ears ever implanted? Most studies are now showing that this is probably going to be the standard.

How is the cost then justified in a country where basic needs are not being met? The cost to the state of educating and “sheltering” a hearing impaired person is estimated at over R10 Million rand in the lifetime of the person. This includes “lost potential income”. As most cochlear implanted patients can be mainstreamed, the long term saving is profound.

Will more surgery be performed as new technology becomes available? The implanted device is designed to last a lifetime. The external speech processor, that is responsible for converting the sound into signals and sending this information to the implanted device, is dependent on software. This can be upgraded as technology improves. 

Will children outgrow the internal device and require a new one? No, the cochlea is fully formed at birth. The electrode array that is part of the implanted device is designed to accommodate skull growth in children. 

Should I wait for new cochlear implant technology? No. The advantage of implanting earlier and benefiting from the “audible world” in terms of stimulation, quality of life improvements, enjoyment and language development far outweigh the disadvantages of possible design improvement that may be lost. This is because the design of the surgically implanted device and electrode array has changed relatively little during the history of cochlear implants. Speech-coding strategies and software algorithms have improved significantly over the years. The speech processor can be upgraded to incorporate new technology when available. 

Can people with cochlear implants identify environmental noises as well as speech? Performance in speech perception varies among individuals. With time and therapy, most implanted patients understand more speech than with hearing aids and many communicate by telephone or even can enjoy music. 

Can people with cochlear implants swim, shower and participate in sports? Yes. As long as they are not wearing their external processor, they can do virtually anything. Restrictions do apply to skydiving and scuba diving because significant changes in air pressure are not advised. Protective headgear to prevent damage to the implanted device is recommended during sporting activities.

Ear,Nose and Throat Specialists