Recent News and Articles on the Keywords: cochlear implants + implant surgery + cochlear  Related to the article below (Last Update: 8/7/2008)

Hornsby and Upper North Shore David can hear the birds whistle again Hornsby and Upper North Shore, Australia - The Royal Institute for Deaf and Blind Children arranged for little David to come to Australia to receive a cochlear implant which costs $26000 donated by ... findingDulcinea Experimental Implants May Be Answer for Lazy Eye findingDulcinea, New York - If successful, the implantable lens could join the ranks of other revolutionary implants, such as the cochlear implant, which provides sound to the deaf or ... Cochlear implant patients share their stories Porterville Recorder, CA - Jul 29, 2008 These implants are for people who are deaf or hearing-impaired. Cochlear implants are for patients who have lost hearing in both ears, whereas BAHA implants ... Cochlear Announces Landmark Milestone Performing 120000 Cochlear ... DOTmed.com (press release), NY - Jul 30, 2008 Since the first commercial implant in 1982, cochlear implants have become the standard of care for people who have severe to profound hearing loss. ...ASX:COH As It Stands - Prosthetic ears, thieves, and payback Times-Standard, CA - Aug 3, 2008 Then a medical breakthrough became available in 1984 when a Australian cochlear implant was approved by the United States Food and Drug Administration to be ... Nemours clinic delivers sounds of progress Bizjournals.com, NC - Jul 25, 2008 They also argue that devices like the implant can make a child feel inferior and subject to abuse from peers. Proponents of cochlear implants, like Horlbeck ... 30 years on, implants still hear Herald Sun, Australia - Jul 31, 2008 Dr Briggs said early diagnosis and bilateral implants gave children the best chance of a normal life. Cochlear implant inventor Prof Clark said today's ... Hearing aid spells growth, market share for Med-El Bizjournals.com, NC - Jul 18, 2008 Pillsbury says the average cost of implant surgery, which embeds an artificial device with an array of electrodes into the cochlea of the inner ear, ... FOX Files: Romanian Girl Gets Cochlear Implant MyFox Saint Louis, MO - Jul 17, 2008 Cochlear implants are not for everyone. It involves surgery to implant the device. They don't work for everyone and they are very expensive ? around $65000 ... Study: Cochlear Implant Improves Hearing in Noisy Environments MedIndia, India - Jul 11, 2008 Ninety-one per cent said that music sounded pleasant with their cochlear implant, while 82 per cent reported listening to music every week, if not every day ...

Cochlear Implants

Sometimes called a "bionic ear," the cochlear implant offers the hope of regaining or restoring the ability to sense sound for some people who have experienced significant hearing loss. Although they're not miracle devices, cochlear implants help some children and adults, whether they're born deaf or whether hearing loss occurs later in life, experience talking on the phone, listening to music, and hearing the voices of their friends and loved ones - things a person with normal hearing often takes for granted.

What Is a Cochlear Implant?
A cochlear (pronounced: ko-klee-er) implant is a surgically implanted device that helps overcome problems in the inner ear, or cochlea (pronounced: ko-klee-uh). The cochlea is a snail-shaped bone located in the area of the ear where nerves are contained. Its function is to gather electrical signals from sound vibrations and transmit them to your auditory nerve (or hearing nerve). The hearing nerve then sends these signals to your brain, where they're translated into sounds you recognize.

If important parts of the cochlea aren't working properly and the hearing nerve isn't being stimulated, there's no way for the electrical signals to get to your brain. Therefore, hearing doesn't occur. (Sometimes referred to as nerve deafness, this is called sensorineural hearing loss, pronounced: sen-so-ree-nyur-ul.) By completely bypassing the damaged part of the cochlea, the cochlear implant uses its own electrical signals to stimulate the auditory nerve, allowing the person to hear.

How Does Normal Hearing Occur?
The ear is made up of three parts, and sound for a person who has normal hearing passes through all three on the way to the brain. The outer ear is made up of the outer, visible part of your ear and the ear canal. When a person is exposed to a sound, the outer ear captures the sound vibration and sends it through the ear canal to the middle ear, which consists of the eardrum and three tiny bones. The sound vibration then causes motion in the three tiny bones, which makes the fluid in the cochlea move. The motion of the fluid stimulates the hair cells, which are thousands of tiny hearing receptors inside the cochlea. The hair cells bend back and forth and send electrical signals to the hearing nerve, and the hearing nerve then carries these signals to the brain, where they're interpreted.

Through aging, heredity, disease, infection, or repeated or severe exposure to loud noise, hair cells can be damaged or destroyed. If the hair cells don't work, the hearing nerve can't be stimulated and therefore can't send information to the brain. Thus, the person is unable to hear.

Hearing loss can be mild, moderate, or severe, depending on the number of hair cells that are defective, damaged, or destroyed. People with mild or moderate hearing loss may find that hearing aids, which simply make sounds louder, help. Those with profound or severe hearing loss might even have trouble understanding loud sounds. A hearing aid won't help in these cases, and a doctor might recommend a cochlear implant.

What Does a Cochlear Implant Do?
The cochlear implant artificially stimulates the inner ear area with electrical signals, sends those signals to the hearing nerve, and allows the user to hear. Although sound quality is sometimes described as "mechanical" and not completely like that experienced by a person with normal hearing, the cochlear implant provides users with the ability to sense sound that they couldn't hear otherwise.

The actual cochlear implant consists of an implant package, which is secured inside the skull, and a sound and speech processor, which is worn externally (outside the body). Several components of the cochlear implant work together to receive sound, transfer it to the hearing nerve, and send it to the brain.

The implant package is made up of:

• a receiver-stimulator that contains all of the electronic circuits that control the flow of electrical pulses into the ear
• an antenna that receives the signals from the external sound and speech processor
• a magnet that holds the external sound and speech processor in place
• two wires containing electrodes that are inserted into the cochlea (the number of electrodes can vary depending on the cochlear implant model type used). The electrodes act much like normal functioning hair cells and provide electrical charges to stimulate the hearing nerve.

The sound and speech processor is a minicomputer that processes sound into digital information, and then sends that information to the implant package in the form of electrical signals. The sound and speech processor is worn externally and looks a lot like a normal hearing aid. Depending on the type of sound and speech processor used, it can either be worn as a headset behind the ear or in a belt, harness, or pocket.

The components of the sound and speech processor include:

• the actual sound and speech processing device (which can either be a body-level model that can be clipped onto clothing like a portable radio, or an ear-level model that's hooked over the ear)
• a microphone
• a transmitter that sends the signals to the implant package. The transmitter also includes a magnet that helps the user align the processor with the implant package.

For the cochlear implant to work, the implant package and the sound and speech processor must be aligned - that's what the magnets are for. By lining up the magnets, both the implant package and sound and speech processor are secured and work as one device. When the implant package and the sound and speech processor aren't completely aligned, the device doesn't work and the person can't hear. Because both components need to be aligned for the user to hear, some people take the sound and speech processor off at night to sleep soundly. Others leave it on all the time.

How Does a Cochlear Implant Work?

Understanding what, exactly, the cochlear implant does may help children appreciate their new bionic ear and the cool technology that's behind it that allows them to hear better. Here's how the implant works:

• The microphone picks up sound.
• Sound is sent to the sound and speech processor.
• The sound and speech processor analyzes the sound and converts it into an electrical signal. (The signal contains information that determines how much electrical current will be sent to the electrodes.)
• The transmitter sends the signal to the implant package, where it's decoded.
• The implant package determines how much electric current should pass to the electrodes and sends the signal. The amount of electrical current will determine loudness, and the position of the electrodes will determine the sound's pitch.
• The nerve endings in the cochlea (the area where the hair cells are located) are stimulated and the message is sent to the brain along the hearing nerve.
• The brain interprets the sound and the person hears.

What Does the Surgery Involve?

The actual surgical procedure, which takes 3 to 5 hours and uses general anesthesia, involves securing the implant package under the skin and inside the skull, and then threading the wires containing the electrodes into the spirals of the cochlea. To secure the implant, the surgeon first drills a 3- to 4-millimeter bed in the temporal bone (the skull bone that contains part of the ear canal, the middle ear, and the inner ear). After the implant is positioned, a small hole is drilled in the cochlea and the wires containing the electrodes are inserted. The implant package is then secured and the incision is closed.

After your child has had cochlear implant surgery, he or she:

• will probably be able to go home the next day
• will have to wear a dressing over the implant area for 24 hours
• may be off-balance or dizzy for a few days
• may experience mild to moderate pain (your child's doctor may recommend that you give your child acetaminophen, such as Tylenol, or ibuprofen, such as Advil or Motrin)
• won't have to have the stitches removed - they're absorbable and dissolve on their own
• can lie on the side with the cochlear implant in a few days

At least a month after surgery, the sound and speech processor is matched with the implant package and is programmed and fine-tuned to meet your child's individual hearing needs.

Learning to Use a Cochlear Implant

After 4 to 6 weeks of healing and getting used to the implant, the person is ready to begin using the sound and speech processor.

Because the extent and type of hair cell damage, electrical signal patterns, and sensitivity of the hearing nerve are all different for each person, a specialist must fine-tune the sound and speech processor for each individual. By measuring the lowest and highest current for each electrode, the clinician finds the softest and loudest sounds that will be heard (each electrode produces a different sound with different pitch). The sound and speech processor matches sounds on different electrodes with different volumes and attempts to create an accurate version of the original sound. However, because there are a limited number of electrodes taking over the function of the thousands of hair cells in a normal ear, sounds won't be totally "natural."

After the first few programming sessions, the user begins to pick up sounds with the implant, but giving the implant full power is a gradual process that takes several weeks. In children who are born deaf, the stimulation from the implant will allow them to develop the brain pathways necessary to hear sounds. This is an extended process with programming and intensive therapy that often lasts for several years.

During the programming process, the user attends speech and language therapy sessions to help identify and interpret the new sounds he or she is hearing. In addition, an important part of the therapy includes parent education and training.

Therapy will help a child develop and understand spoken language through detecting, imitating, and associating meanings of sounds. These sessions last at least a year, along with parent education and training programs. In many cases, therapy has helped children with cochlear implants develop speech and language on par with their peers and attend mainstream schools.

Can a Cochlear Implant Restore Hearing for Everyone?

Cochlear implants are very successful for some people, but not everyone is a candidate to receive one. Ideally, children 12 months of age or older with profound hearing loss in both ears are excellent candidates, but not every child is eligible.

Some common reasons that a child may not be eligible for a cochlear implant:

• the child's hearing is "too good" (meaning the child can hear some sound and speech with hearing aids)
• the reason for hearing loss isn't a problem with the cochlea
• the child has experienced profound deafness for a long period of time
• the hearing nerve itself is damaged or absent

Each potential candidate must be evaluated by a cochlear implant team to determine whether a cochlear implant is the best option.

For those who do receive a cochlear implant, benefits can vary. The length of rehabilitation varies from person to person, and many factors such as the condition of the hearing nerve or the presence of scar tissue in the cochlea can hinder the success of the implant. Expectations should be realistic, and your child's doctor or surgeon will help you understand the level of success the implant can reasonably achieve for your child.