Frequently Asked Questions

Q1. What Is A Cochlear Implant? A1. A Cochlear Implant is a device designed to help severe to profoundly deaf individuals who gain little or no benefit from hearing aids. With their cochlear implant they gain awareness of environmental sounds, most can understand speech without lip-reading and some can use the telephone. The cochlear implant system converts acoustic sound waves into weak electric currents, which are delivered to the immediate vicinity of the auditory nerve in the inner ear or cochlea. The auditory nerve is stimulated by these electric currents and transmits nerve impulses to the brain, where they are understood as acoustic sensations. Q2. According To My Doctor, I Suffer From Nerve Deafness. Does This Mean That The Hearing Or Auditory Nerve Is Destroyed? A2. No, the auditory nerve may still potentially function even in cases of nerve deafness; in most cases the auditory nerve is intact (or partially functional), but the hair cells in the cochlea are damaged or destroyed. Normally, when sound waves reach the ear they are converted into electric currents by tiny sensory hair cells. The auditory nerve responds to the electric current and passes it on to the brain. We experience this as "hearing". If the hair cells are damaged, there is no mechanism to convert the sound waves into electric currents, and without electric current the nerve is not stimulated. As a result nothing can be heard. Q3. In Other Words, Damage Or Destruction Of The Hair Cells In The Cochlea Can Result In Total Deafness, But The Auditory Nerve Can Still Be Fully Intact? A3. In principal, yes! In most cases, however, part of the nerve is in fact damaged. Q4. How Can The Cochlear Implant Help? A4. The cochlear implant conveys weak electric stimuli to the vicinity of the auditory nerve. The electric stimulus activates the nerve, which then transmits a signal to the brain. The brain recognizes this signal and we experience this as "hearing". The cochlear implant has the same function as the hair cells, in that it transforms sound into an electric current that stimulates the auditory nerve. Nevertheless, the result is not the same as normal hearing. Q5. How Many Parts Are There To A Cochlear Implant System? A5. A cochlear implant consists of two main components: a. The internal component, Cochlear Implant, which is implanted surgically, and b. The external components, Speech Processor, Microphone & Transmitter Coil, which are worn outside the body. Q6. What Does The Internal Component Consist Of? A6. The inner component or implant package contains an induction coil and an electrode array (see diagram of cochlear implant system). With surgery this implant package is implanted in the Temporal bone behind the ear. The electrode array is introduced into the inner ear (cochlea). An electric current across the electrode array activates the auditory nerve and the result is that you "hear". What Is The Purpose Of The External Component Of The Cochlear Implant?
A7. The external part converts sound waves into electric signals. It consists of a microphone, a small speech processor and an external coil (see diagram of cochlear implant system). The microphone picks up the sound waves and transforms them into weak electric signals. The speech processor modifies these electric signals. They are then sent to the external coil via a cable. If the external coil is placed over the internal coil, signals will be transmitted through the intact skin to the implant and electrode array. In this way the auditory nerve is stimulated, which results in acoustic sensations. Q8. How Large Is The Speech Processor? A8. Behind The Ear (BTE) – the size of a high powered Hearing Aid
Body worn – the size of a small walkman radio or pack of cards Q9. Where Is The External Coil Situated? A9. The external coil must be placed on the skin exactly over the internal coil in the implant package. If the two coils are not correctly aligned, the sound impressions will become quieter or vanish entirely. Correct positioning of the external coil is therefore essential. Q10. How Can The External Coil Be Correctly Positioned? A10. The external coil contains a magnet that is attracted by a second magnet inside the implant package, which places it into the proper position on the skin. Hair does not normally need to be removed./