Cochlear Implant Surgery Side Effects

A cochlear implant is a device that works to restore hearing to those who cannot benefit from hearing aids. A candidate usually has profound to severe sensorineural deafness in both ears and should have enough intact aural nerve endings to benefit from the device. Cochlear implant surgery is a relatively safe procedure that can be performed on adults in good health and on children as young as 12 months old. Side effects are minimal, but as with any kind of surgery, there are risks to consider.

Function

• A cochlear implant consists of an internal receiver that is surgically implanted behind the ear and an external earpiece that translates sound into electronic signals. A cochlear implant is not a hearing aid. It works by using electrodes to bypass the damaged part of the inner ear and send auditory cues to the brain. In contrast, a hearing aid only amplifies sound and is useless for those with nerve damage.

Benefits

• Normal hearing is not fully restored with a cochlear implant. Speech and environmental noise do not sound the same, and the brain must relearn how to identify what it hears. Benefits vary greatly among candidates depending on how long they have lived with hearing loss, how well their brain can adapt to new stimulus, and their belief that the device will improve the quality of their lives. Hearing recognition improves greatly over time when combined with rehabilitation exercises, lip reading and speech therapy.

Minor Side Effects

• Although a cochlear implant procedure is considered major surgery, there are relatively few side effects, and these usually abate after a few weeks. Minor side effects include nausea, disorientation, dizziness, pain and/or pressure around the ear and sore throat from the insertion of a breathing tube. Some people experience a metallic taste in the mouth or have other taste disturbances that may persist for a few months. Those who experienced tinnitus, or head noise, prior to surgery may find their symptoms have lessened, while for others tinnitus may increase.

Major Side Effects

• Serious side effects include a disturbance of facial nerves on the side where the device was implanted. The procedure requires close contact with facial nerves, and if they are damaged during surgery a temporary facial paralysis may result. This is a rare occurrence that can be treated with steroids or antiviral medications. Another side effect is the leakage of cerebrospinal fluid around the brain, which can cause inflammation and infection.

Considerations

• Cochlear implant recipients may be at an increased risk for contacting bacterial meningitis. Those with congenital inner ear malformations, cerebrospinal fluid leaks, recurrent ear infections, a history of meningitis, a weakened immune system, or who are younger than 5 age are especially susceptible. Patients who receive a cochlear implant should be immunized against the disease as a precaution.