Cochlear Implants – A Primer

Cochlear implants are electronic devices with three principal elements: a battery-operated external speech processor that converts sound waves into digital signals, a magnetically attached connector that transmits the signals to the implant, and an internal implant surgically placed under the skin on the skull and linked by a wire array to the hearing nerve.

The speech processor is essentially a mini-computer that processes sound waves electronically and sends them to the implant so the sounds can be understood by the brain as speech. Multiple programs give the user flexibility to adapt to different hearing situations.

Implants come in behind-the-ear (BTE) models and body pack versions. Most wearers choose the BTE model that became available in 2000. Body packs continue to be employed because of bone structure or other special circumstances.

Who Is Eligible for Cochlear Implants?

Increasingly, CIs are installed where hearing aids have failed to establish satisfactory speech thresholds. As of mid-2005, an estimated 90,000 persons have received implants worldwide, more than 30,000 in the United States. Implants are installed for infants as young as 12 months, as well as persons of all ages with a severe to profound hearing loss. Individuals in their 80s and early 90s have received implants.

Cost and Insurance Coverage

The surgery costs many times more than even a pair of top-of-the-line hearing aids; however, many health insurance policies and Medicare underwrite a substantial portion under “medical necessity” coverage.

A “medical necessity” letter from a physician or audiologist is required in the U.S. to establish implant eligibility. In effect, the letter certifies that surgery is required to deal with the hearing needs of the patient. Strict Federal standards enforced by the Food and Drug Administration (FDA) govern eligibility for implant surgery. These standards, set up in 2005, require 60% or less sentence discrimination in the best-aided condition, with 50% or less in the ear being implanted. Medicare’s standard for expense reimbursement requires speech understanding of 40% or less.

Surgical Procedure

Surgery is required on the head above the ear to insert a small disc-like device next to the skull. It is usually performed as day surgery unless there is bone structure irregularity (rare) or other special condition. The implant usually eliminates residual hearing in that ear.

The surgeon threads a wire array through the cochlea (hence the name cochlear implant) where it is linked to the hearing nerve and brain. The implanted wire array transmits the signals in their component speech frequencies.

Typically only one ear is implanted, although dual implants are sometimes used. Many CI wearers use a hearing aid in their other ear. Wearing devices in both ears helps with determining sound direction and dealing with background noise.

Dr. Chad Ruffin offers more information on cochlear implant surgery and on potential complications. Dr. Ruffin is an ENT doctor and surgeon in Washington State.

Getting Used to an Implant

Auditory therapy is often recommended “breaking-in” process, depending on the extent and character of the hearing loss and receptivity to the implant’s new sounds. Some patients find that implants improve speech understanding in a day or two without therapy, but others may take weeks or months to reach acceptable levels, even if assisted by speech-language therapy. In-person auditory therapy generally works better than what you find online. Although at first, voices may resemble Donald Duck or sound electronic, with time and training, the brain accepts the new sounds as normal. As one veteran implant audiologist put it, “That old brain continues to learn new tricks.”

This outstanding blog post shares the details, challenges, and triumphs of a successful cochlear implant journey.

Getting Support and Help with Your CI

Getting a cochlear implant means you’ve taken a big step, and your hearing may change for the better. But you still may have questions, concerns, or need support. As always, finding community and resources can make a big difference in your journey.

Here are some ways to make sure you’re getting the best from your CI.

Facebook has several cochlear implant support groups. You may find one that works for you. This one is active every day:
- Cochlear Implant Support Group | Facebook
Cochlear America has mentors, events, and an ongoing care program called Cochlear Family.
Advanced Bionics has mentors, a forum, and a blog.
Med-El has a HearPeers program and Facebook discussion group.

Finally, each manufacturer has apps that will help you use your CI effectively.