What is the difference between a Cochlear Implant and a Bone Anchored Implant?
July 23, 2012
When someone with a hearing loss comes into our Center, we talk with them about many different technology options to help them reconnect to their world. Most people are familiar with hearing aids. However, many have questions about a Cochlear Implant or a Bone Anchored Implant, often called a Baha, and wonder if these implants would be an option for them.
A Bone Anchored Implant is appropriate for someone where traditional hearing aids are not efficient because of draining ears or chronic infections, blockage or damage in the outer or middle ear or loss of all hearing in one ear such as following an acoustic tumor removal. Candidates have either a conductive hearing loss or a single sided deafness. The bone anchored implant uses a titanium device placed in the skull behind the ear and a sound processor that attaches to the implant. The sound processor will collect sounds from the environment sending vibration into the implant which in turn vibrates the bone. This bone vibration bypasses the outer and middle ear and stimulates the inner ear. The hair cells inside the inner ear convert the sound to electrical impulses that travel to the brain allowing the recipient to hear naturally. A Bone Anchored Implant can be surgically placed on a child starting around 5-years of age. However, even infants can successfully use a Bone Anchored Implant by using a soft-band to hold the processor in place. For adults, there is no upper age limit to receiving and using a Bone Anchored Implant. Recipients report being happy to be free of hearing aid earmolds and that they are understanding speech in noise better than they were able to with their hearing aids.
A Cochlear Implant candidate differs from a Bone Anchored Implant in that they have a greater degree of hearing loss. They have a severe to profound sensorineural hearing loss (often called “nerve deafness”) in both ears where traditional amplification is no longer beneficial. Often times candidates report that wearing a more powerful aid or increasing the volume of their hearing aid is like turning up the volume on a bad speaker. It can make sound louder but more distorted. A sensorineural hearing loss can be caused by illness, head trauma, malformation of the inner ear, exposure to loud noise, general aging or other unknown causes. The Cochlear Implant is a two part system where the internal device is surgically placed under the skin and the sound processor sits on the outside of the ear capturing sounds from the environment. The processor translates the captured sound into digital information sends it to the internal implant which in turn converts the digital information into an electrical signal that stimulates the auditory nerve bypassing the damaged portion of the inner ear. The electrical signals are sent to the brain and are perceived as sound. Cochlear Implants can be placed on children as young as 12-months of age and there is no upper age limit for cochlear implant use. Cochlear Implant recipients report that they are able to relax and not work so hard to communicate with friends and family any more and are excited to share stories of all the “new” sounds they forgot were in their world.
If you have a hearing loss or know someone who does and want to find out if traditional amplification or these implant technologies can help, ask an Audiologist or call our Center at 206-215- HEAR (4327).