Cochlear Implants
A cochlear implant gives a person a way to hear when a hearing aid is not enough. Unlike a hearing aid, a cochlear implant does not make sounds louder. Instead, it sends sound signals directly to the hearing nerve. These signals go around the parts of the inner ear that are not working well. Cochlear implants are not a “cure” for hearing loss. They allow a person with hearing loss to make out sounds.
How do I know if my child needs a hearing aid or a cochlear implant?
Hearing aids work for most children with hearing loss, but when a child will do better with a cochlear implant, your audiologist or hearing health care professional will suggest one. Your child’s candidacy will be based on the type and severity of hearing loss as well as the structure and shape of the inner ear. As hearing loss is commonly identified in very young infants, it is recommended that children start with hearing aids initially and then be considered for a cochlear implant once they’re older.
How does a cochlear implant work?
Developed in large part at the House Institute by William House, MD, a cochlear implant is a surgically implanted electronic device that provides a sense of sound to a person who is profoundly deaf or severely hard of hearing. An implant does not restore normal hearing. Instead, it can give a deaf person a useful representation of sounds in the environment and helps him or her to understand speech.
The implant consists of an external portion that sits behind the ear and a second portion that is surgically placed under the skin. The basic parts of the device include:
- A microphone that picks up sound from the environment
- A speech processor that selectively filters sound to prioritize audible speech and sends the electrical sound signals through a thin cable to the transmitter
- A transmitter, which is a coil held in position by a magnet placed behind the external ear; it transmits the processed sound signals to the internal device by electromagnetic induction.
- A receiver and stimulator secured in bone beneath the skin, which converts the signals into electric impulses and sends them through an internal cable to electrodes
- An array of up to 22 electrodes wound through the cochlea, which send the impulses to the nerves in the scala tympani and then directly to the brain through the auditory system
How is a cochlear implant placed in the ear?
Surgery is needed to place a cochlear implant. The surgery takes up to a few hours and general anesthesia is needed. It takes several weeks for the skin over the surgery site to heal fully, but children usually return to normal activities in about 7 to 10 days.
Once your child receives a cochlear implant, they will have to return to the House Children’s Hearing Center four to six weeks after surgery to have the cochlear implant turned on, or activated. After the cochlear implant is activated, your child will need more visits to ensure the implant is optimally programmed.
Parental preference for hearing loss treatment
The decision to have a cochlear implant is complex. An implant is a long-term commitment leading up to and following surgery. Following surgery, speech therapy is often employed to maximize the benefit of the implant on language development. In addition, follow-up visits with your House Children’s Hearing Center physician and audiologist are required for at least one year, and often more, following the implant to assess the success of the procedure and check for any issues.
A cochlear implant is not for everyone. Some children perform well with hearing aids alone, and the decision to proceed with an implant will be made in conjunction with the parents, the child (if appropriate), and the entire House Children’s Hearing Center Team, including the physician and the audiologist.