Cochlear implantation involves a team of people with a range of training and skills. Teams include specially trained ear, nose and throat (ENT) physicians, audiologists, and speech language pathologists. Other members of the team might include a social worker, a teacher of children with hearing loss, and a psychiatrist or psychologist.
As a specialized procedure, cochlear implant (CI) surgery is not performed in all ENT clinics. Cochlear implants are a specialized intervention undertaken by individuals who have chosen to specialize in this device. Unlike other interventions, a cochlear implant is a life long process that requires care over a person's lifetime. The best outcome is dependent upon more than just surgery. Mapping or programming of the external sound processor by a CI audiologist is required every 3 to 6 months during the first year. Typically after the first few years, annual audiology visits are recommended. Additionally, auditory (re)habilitation services provided by the CI team or a recommended professional outside of the clinic will help children and adults reach their full potential with the CI device.
The first step in the hearing evaluation is to have a pure-tone audiogram taken with and without hearing aids. The audiogram determines the type and degree of the hearing loss. The audiogram can indicate the origin of your hearing loss and whether it originates in the inner ear or elsewhere. The severity of the hearing loss is reflected by the pure tone average hearing thresholds. This information serves as a key parameter in the decision regarding whether an individual candidate meets the audiological criteria for cochlear implantation. Information regarding which sounds are perceived best by a CI candidate is reflected by the shape of the audiogram. The audiogram also enables the audiologist to compare ears as well as aided (with hearing aids on) and unaided outcomes. It is helpful for individuals undergoing an evaluation to have and share past audiological records. Comparison of audiograms over time can indicate whether the hearing loss is stable, fluctuating, or progressive.
In order to minimize the steps to determine candidacy, an individual should visit their audiologist or hearing aid dispenser about one month before the first visit to the CI center for any necessary refitting and maintenance. If the dispenser's recommendation is to purchase new hearing aids, it is recommended that the candidate wait until the CI clinic has made a candidacy determination. Sometimes, individuals are encouraged to try newer or stronger hearing aids even though they will derive greater benefit from CI.
To read more about the evaluation process, click HERE.
Consideration of Bilateral Implantation
Many cochlear implant users have residual hearing in their non-implanted ear. To provide binaural and more balanced hearing a hearing aid in the opposite ear may provide benefit. For individuals with a more severe hearing loss and minimal benefit from a hearing aid, a second cochlear implant may be recommended. Binaural hearing offers the benefit of improved speech perception in noise (and quiet), better sound localization and greater access to sound generally.
For more information on binaural hearing, click HERE for presentations from ACI Alliance conferences.
Medical Assessment and Surgery
The medical assessment addresses the candidate’s overall health, hearing loss history, and etiology of the hearing loss. The surgeon will exam the condition of the ear and cochlea. Radiologic testing will be performed prior to surgery to allow visualization of the cochlear anatomy. The implant surgery will be performed under general anesthesia and generally takes two to three hours. The surgery is typically performed in the outpatient setting; sometimes an overnight stay will be required—a decision made by the surgeon. Patients typically return for a follow-up medical appointment once week post surgery.
Post Operative Audiology Appointments
Two to four weeks after surgery, the patient is fit with the external part of the cochlear implant, which is called a sound processor. A cochlear implant audiologist uses a computer to adjust each of the individual electrodes to levels that allow the recipient to best hear sounds. The process is similar to a hearing test in which a patient listens to tones to determine the most comfortable and effective level of sound for the individual. These levels are stored on the speech processor; this data is often referred to as a “map.” After the audiologist measures and saves this data, the sound processor is turned on and the person hears with a cochlear implant for the first time.
Several appointments may be needed after this initial activation to adjust the program as patients adapt to sound and practice listening with the device. The number of appointments needed varies by the person but is typically 3 to 6 appointments the first year and one appointment per year after that.
For more information on speech and sound coding, click HERE for presentations from ACI Alliance conferences.
After activation of the sound processor, recipients will be encouraged to practice listening to speech as well as the sounds in the environment, learning to apply meaning to those sounds. An auditory (re)habilitation program will help the recipient reach their full potential with a cochlear implant. Auditory therapy for children is essential; and is strongly encouraged for adults. Therapy goals are individualized to meet patient needs and are also impacted by the age of the individual and their hearing history. In recent years, it has been recognized that involving parents in the therapy process for children has a positive effect on a child’s progress as it facilitates family involvement. No longer do parents sit in the waiting room while their child sees a habilitation specialist. Many centers provided therapy at the CI clinic. If they do not, the CI audiologist will recommend an auditory therapist with appropriate training and experience.
To read more about adult rehabilitation after cochlear implantation, visit our blog site: http://acialliance.site-ym.com/page/AdultRehab
To read more about habilitation for children after cochlear implantation, click HERE for presentations from ACI Alliance conferences.
For both children and adults, the inclusion of music in the therapy process of (re)habilitation has proven to improve listening skills for some CI users. Music heard through a cochlear implant provides much more limited access to tones that are inherent to melody. Working in collaboration with a music therapist often leads to improved perception of melody, rhythm, pitch and timbre.
For more information on Music Training as part of (re)habilitation, click HERE for presentations from ACI Alliance conferences.