A cochlear implant is an electronic device that transmits electrical impulses to the brain where they are perceived as sounds both for children who are born deaf or become deaf and also deaf or severely hard of hearing adults.
The cochlear implant consists of two parts:
- the external part with a speech processor incorporating a microphone which is placed behind the ear with a transmitter coil or with a compact, single-unit audio processor that is held in place by magnets over the implanted receiver
- a surgically implanted internal part consisting of a receiver package implanted in a recess in the mastoid bone which is connected to the electrode array positioned within the cochlea.
Today the possibility of obtaining a cochlear implant in Europe is still very uneven and depends in particular on the social insurance system of the country concerned.
It should be remembered that health policy in the European Union is in the first place the responsibility of each state member.
Numerous indicators show a definite increase in the quality of life after a cochlear implantation and consecutive rehabilitation.
The CI provides better results than conventional hearing aids in many cases, facilitates the integration of children into mainstream education and provides adults with a better chance of being able to integrate socially and professionally.
The overall impact for a child with a CI is generally higher than for an adult. As regards the child’s impact, it includes also the likelihood that less special educational school may be required.
Furthermore other social costs are likely to be saved, e.g. unemployment allowances, due to the fact that CI users are much more likely to be able to find a job.
Most of the cost-benefit studies undertaken show clear advantages for cochlear implantation in both adults and children.
The CI has a positive impact on the quality of life of the individual that is both long term and sustainable for a relatively modest cost and is therefore a net advantage for Society and facilitates the inclusion of citizens with this disability.
Research is being conducted into ways to further improve the functioning of cochlear implants in noise and other environments, to improve the ability for CI users to use TV, phones and to enjoy music. The preservation of residual hearing during cochlear implantation, especially in those candidates who have significant residual low frequency hearing and can benefit from electro acoustic stimulation, is also being researched.
All adults with severe / profound or total hearing loss, acquired and possibly to some extend congenital should be considered as potential candidates for a cochlear implant. The hearing loss must be of sufficient degree so that, even when aided, speech perception through audition alone is limited. The decision as to whether or not to be implanted must depend upon the informed consent of the individual involved and, last but not least, also upon the recommendation of a health care multidisciplinary team. The potential advantages /disadvantages of not being implanted must be taken into account.
Potential cochlear implant candidates must be fully informed of the entire process including the pre-operative investigations, the surgical procedure, and the post-operative program. Only those multidisciplinary CI-teams which offer before satisfactory range of pre and post-operative services (long and medium term rehabilitation programs) should be considered. Rehabilitation programs must include psycho-social rehabilitation, such as communication strategies. Supportive signs have proved to be of good assistance to deafened adults with CI.
Candidates for cochlear implants should be assessed and implanted in centres with fully qualified staff having evidence of expertise. Factors to consider are the experience of the centre, the nature of the pre-operative assessments, the frequency of routine follow-up assessments, and whether or not a rehabilitation program is recommended and conducted. When in doubt, the CI candidate should obtain a second opinion.
Not only children but also adults should have access to bi-lateral cochlear implants if it is considered they can benefit from them. This means that national health services should establish corresponding health programs to make this possible.
As a general rule, the decision to implant should be made as soon as possible after an acquired severe to profound hearing loss has been diagnosed, and as early in the child’s life as possible for those with congenital hearing loss.
The earlier a child is implanted the more likely normal speech and language capabilities will be developed by deaf children without additional needs, with minimal delay as compared to normal hearing children. The earlier the implant is undertaken, the greater is the expected impact on his/her speech development. This underlines the necessity for and importance of a neonatal screening program.
The final decision about cochlear implantation must only be made with the consent of the parents.
The professional teams involved in the implant process must provide the parents with all the information they need to make such a decision.
It has to be considered that 95% of the parents of deaf children are both normal hearing having no experience with deafness or sign language and the child is the only deaf child in a hearing family. Learning the spoken language from the child’s environment is one of the main issues for deaf children using cochlear implants.
Specific speech therapy training sessions are necessary to achieve good auditory perception, speech and language skills. A favourable social environment and the involvement of the family are also of utmost importance. If audition is not intensively and continually stressed in the training program, it is less likely that the full potential benefits of the implant will be realized. We also know that, for their social emotional development, it is very important that these deaf children have regular contact with other deaf children and deaf peers.
Others modes of communication which children, in particular older children, used before the implant process such as cued speech, lip-reading, sign language do not negatively impact on the benefits of cochlear implantation.