A cochlear implant is a surgically implanted device that bypasses damaged hair cells in the ear and provides electrical stimulation directly to the auditory nerve, giving patients who are severely hearing impaired or profoundly deaf the ability to hear. It is most beneficial for those who cannot be helped with a traditional hearing aid.
A cochlear implant works differently than a hearing aid. Hearing aids amplify sounds so that a person with nerve damage can hear more clearly. Cochlear implants generate an electrical signal that the brain interprets as sound. The implant has an external portion that sits behind the ear, consisting of a microphone, a speech processor and a transmitter. These work in tandem with the internal components, a receiver and array of electrodes, which have been implanted in the ear. The microphone picks up sound and sends it to the speech processor, which converts these signals to digital impulses and sends them to the transmitter. The transmitter, in turn, sends the processed audio signals to the receiver. From there, they are transmitted directly to the brain through the auditory nerve. While a cochlear implant does not cure deafness or restore hearing loss, it does allow a patient to perceive sound, and can help him or her to converse again.
If you are experiencing severe to profound sensorineural hearing loss (the result of nerve damage to the inner ear) and can’t benefit from conventional hearing aids, you are a prime candidate for cochlear implants. These implants are most helpful in patients with solid language and communication skills and a hearing loss that occurred later in life. Younger children (typically between the ages of two and six) also benefit, since a cochlear implant exposes them to sounds during their formative learning years, while they are developing speech and language skills. Post-implantation therapy is a crucial component in the success of cochlear implants; learning to use them correctly takes time and effort.
Bone Anchored Hearing Aid, or Baha, is a hearing device that relies on direct bone conduction to transmit sound. This surgically implanted device bypasses the auditory canal and middle ear, utilizing bones as a pathway for sound to reach the middle ear. It’s an alternative for people with chronic ear infections, congenital external auditory canal atresia and single-sided deafness. These patients usually do not benefit from conventional hearing aids.
In a person with normal hearing, sound enters the external ear and travels down the ear canal through the middle ear to the cochlea, or inner ear. This process is called air conduction. For individuals with certain types of hearing loss, sound is unable to travel down these pathways. The Baha system takes advantage of the bones’ natural conductive abilities by sending sound vibrations directly to your inner ear, bypassing the auditory canal and middle ear completely.
The Baha device is made up of three components: a titanium implant, an external abutment and a sound processor. Once the surgical implant is in place, it gradually fuses with the skull bone over a period of several months in a process known as osseointegration. The Baha unit is then ready to be fit and programmed. The sound processor transmits vibrations through the external abutment to the implant, where vibrations in the skull and inner ear stimulate the nerve fibers responsible for hearing.
Baha is a safe and effective FDA-approved treatment alternative that enables many hearing-impaired individuals to communicate more effectively. It has been available in the U.S. since 1977.
Candidates for Baha are typically patients with conductive and mixed hearing losses, or those with unilateral (single-sided) hearing loss.
If you experience chronic ear infections that do not respond to treatment, you may find the Baha system particularly beneficial. Conventional hearing aids can aggravate the condition due to humidity and moisture building up in the ear canals. Those with congenital ear defects (such as ear canals that are narrow or absent) are good candidates, as well.