Med Treatment

What is a Cochlear Implant?
A cochlear implant is an intricate, medical electronic device that is surgically implanted behind the ear to treat hearing loss. A cochlear implant improves hearing by representing sounds better. Patients may not get back normal hearing but they will be able to hear sounds more clearly and will have an improved understanding of speech in environments filled with noise.

How does the Cochlear Implant work?
A cochlear implant consists of internal parts that are implanted beneath the skin and external parts that are worn by the patient. The external part has a speech processor that helps in creating the sensation of sound. The external microphone and processor gathers the sounds in the environment and converts them into electrical impulses.

The cochlear implant sends impulses to the auditory nerve that transmits the signals to the brain. It can bypass the nonfunctional portions of the ear and provide a direct stimulation to the auditory nerve. These signals are then transmitted by the auditory nerve to the brain that perceives the signals as sound.

A cochlear implant does not increase the volume of sound like a hearing aid but it boosts the nervous reaction to sound.

How is the Cochlear Implant surgery performed?

The area behind the ear is shaved and sterilized.
A two to three inch incision is made. This leads to the opening in the mastoid bone and into the middle ear.
The receiver-stimulator part of the cochlear implant is place on a depression that is made on the bone.
The device is kept in place with an enduring suture.
Through the opening in the mastoid bone, another opening is created in the cochlea to implant the electrodes.
The electrode is carefully and very slowly placed through this opening. The structure of electrode is designed to arrange the electrodes very close to the ganglion cells to allow the electrical signals.
When the device is fitted in place, it is tested and the incision is closed with absorbable sutures.

How to prepare for the Cochlear Implant procedure?
The patient may need to go through certain medical tests such as:

Thorough examination of the ear
Audiogram
Hearing aid evaluation
Physical examination
General anesthesia preparation
Psychological test to determine if the patient can deal with the implant

How much time is required?

Approximately 2 hours in surgery.It may take longer for younger children due to the small size of their middle ear structures. For adult and adolescent patients, the cochlear implant surgery is conducted as an outpatient procedure.
Children, however, may require a one-night-stay at the hospital.

What type of anesthesia will be given?

General anesthesia

How will patient recover?

- A bandage around the head needs to be worn during sleep for some time after the surgery.
- The external parts are fitted about one month after surgery when the surgery site has healed. The device is then turned on and mapped, which involves adjusting the speech processor and fixing the stimulation level for each electrode.
- The patient needs to be trained in interpreting sounds that are heard through the cochlear implant for many day or even years.
- Some patients may experience sound sensations that are mechanical or synthetic for a few weeks.

What should be cared?

- Patients who require an MRI may need to remove the magnet in the cochlear implant.
- Care should be taken not to get the external cochlear implants wet. They should be removed before showering, bathing or swimming.
- If the device fails, surgery is required to solve the problem.