A Cochlear Implant is an electrical device used to help patients who have severe hearing loss and do not get adequate benefits from hearing aids. There are several parts to a cochlear implant. The first part is the receiver-stimulator. The receiver-stimulator is the device, which is implanted underneath the skin behind the ear. A small wire from the receiver-stimulator is placed at surgery into the inner ear. The skin is sewn back together and the device is completely underneath the skin.
The speech processor is an external device, which has a microphone that connects with the internal device by radio transmission. A small magnet on the speech processor attached to a wire adheres to the skin over the internal device by magnetism. The speech processor receives sounds and speech from the environment and sends a signal to the internal device (the receiver-stimulator). The receiver-stimulator then sends a signal down Cochlear Implant Receiver to the wire into the inner ear, which the patient can hear as sound.
“A.W., a cochlear implant recipient, has done extremely well with his implant. He began to understand words on the first day. Like most patients, he shows continued improvement over time. He has been very happy with his results.”
The vast majority of patients have improvement in their communication after cochlear implantation. Some patients are able to understand speech much better than previously. Some people are even able to understand speech on the telephone, and some do not need to lip read anymore. However, there is some variability in the results of individual patients. In many cases, this relates to deterioration of the hearing nerve during the period of deafness. Fortunately, the number of patients who do poorly with a cochlear implant is small. Most patients note significant improvement.
Most patients say that speech has a higher pitch than normal but is usually understandable. Many patients describe the sound as "mechanical". Patients have generally much improved awareness of sounds around them. This can be very helpful for safety issues, such as hearing an oncoming car. A few patients are actually able to regain an appreciation for music, but this is less common.
Interestingly, the exact cause of hearing loss does not affect whether a patient will benefit from a cochlear implant. As more and more patients with different types of ear disorders receive cochlear implants, we are finding that the cause is generally not important. Patients have the potential to do well with many different causes of hearing loss. One important note is that patients who are deafened from meningitis and develop new bone inside the inner ear do not have as much benefit from an implant as other patients.
Patients are initially evaluated in the ENT office at Eastern Carolina Ear, Nose, and Throat. A search is made for potentially treatable causes of hearing loss. If the patient has not yet tried hearing aids, a hearing aid trial is begun. If the patient is not sufficiently successful with hearing aids, then a complete cochlear implant audiological evaluation is carried out. If the patient is deemed to be a candidate on detailed hearing and speech testing, they then return for evaluation with the physician and a CAT scan is obtained to study the structure of the inner ear. The patient then has an opportunity to learn more about the surgical procedure and a final decision is made together with the patient and physician. We are currently using the Clarion cochlear implant. To learn about Clarion, click here. To learn about cochlear implants from the cochlear corporation, click here.
P. Bradley Brechtelsbauer, MD, FACS
Sandra Royle-Tabak, Au. D., CCC-A, F-AAA
Ellen Poland, Ph.D., Au.D., CCC-A, F-AAA
Nan Taylor, Masters of Science, Certificate of Clinical Competence in Audiology
Hollie Lilley, OTO-Tech, Hearing Instrument Specialist
Lisa Collins, MS, CCC-SLP
Morgan Greve, MA, CCC-SLP