Cochlear Implant: Hear the World

3rd Part of Article

2009-04-03T05:04:00.000-07:00

Manufacture:

Currently (as of 2007 update), the three cochlear implant devices approved for use in the U.S. are manufactured by Cochlear Limited, Australia, MED-EL, Austria and Advanced Bionics, US. In the EU, an additional device manufactured by Neural, of France is available. Each manufacturer has adapted some of the successful innovations of the other companies to their own devices. There is no clear-cut consensus that any one of these implants is superior to the others. Users of all four devices display a wide range of performance after implantation.

Since the devices have a similar range of outcomes, other criteria are often considered when choosing a cochlear implant: usability of external components, cosmetic factors, battery life, reliability of the internal and external components, MRI compatibility, mapping strategies, customer service from the manufacturer, the familiarity of the user's surgeon and audiologist with the particular device, and anatomical concerns.

Cochlear's 2007 annual report acknowledges that a Federal investigation continues into its payments to physicians and providers. In February 2007, part of the whistleblower complaint against Cochlear filed by former Chief Financial Officer Brenda March was unsealed by the U.S. District Court for the District of Colorado. The complaint alleges that Cochlear violated the Federal anti-kickback statute through its Partners Program, which offered credits towards free or discounted products for physicians who implanted Cochlear devices, as well as gifts, trips, and other gratuities paid to physicians and providers. The government intervened in the case and transferred it from the U.S. Department of Justice to the Health and Human Services Inspector General for the imposition of civil penalties. The amounts of sanctions are not yet known.

What are the Benefits of Cochlear Implants?:

For people with implants:
Hearing ranges from near normal ability to understand speech to no hearing benefit at all. Adults often benefit immediately and continue to improve for about 3 months after the initial tuning sessions. Then, although performance continues to improve, improvements are slower. Cochlear implant users' performances may continue to improve for several years. Children may improve at a slower pace. A lot of training is needed after implantation to help the child use the new 'hearing' he or she now experiences.

Most perceive loud, medium and soft sounds. People report that they can perceive different types of sounds, such as footsteps, slamming of doors, sounds of engines, ringing of the telephone, barking of dogs, whistling of the tea kettle, rustling of leaves, the sound of a light switch being switched on and off, and so on. Many understand speech without lip-reading. However, even if this is not possible, using the implant helps lip-reading.

Many can make telephone calls and understand familiar voices over the telephone. Some good performers can make normal telephone calls and even understand an unfamiliar speaker. However, not all people who have implants are able to use the phone. Many can watch TV more easily, especially when they can also see the speaker's face. However, listening to the radio is often more difficult as there are no visual cues available. Some can enjoy music. Some enjoy the sound of certain instruments (piano or guitar, for example) and certain voices. Others do not hear well enough to enjoy music.

What are the Risks of Cochlear Implants?

General Anesthesia Risks:
General anesthesia is drug-induced sleep. The drugs, such as anesthetic gases and injected drugs, may affect people differently. For most people, the risk of general anesthesia is very low. However, for some people with certain medical conditions, it is more risky.

Risks from the Surgical Implant Procedure:
Injury to the facial nerve --this nerve goes through the middle ear to give movement to the muscles of the face. It lies close to where the surgeon needs to place the implant, and thus it can be injured during the surgery. An injury can cause a temporary or permanent weakening or full paralysis on the same side of the face as the implant.

Meningitis:

This is an infection of the lining of the surface of the brain. People who have abnormally formed inner ear structures appear to be at greater risk of this rare, but serious complication. For more information on the risk of meningitis in cochlear recipients,
Cerebrospinal fluid leakage:

The brain is surrounded by fluid that may leak from a hole created in the inner ear or elsewhere from a hole in the covering of the brain as a result of the surgical procedure.Perilymph fluid leak:
The inner ear or cochlea contains fluid. This fluid can leak through the hole that was created to place the implant;

Infection of the skin wound;
Blood or fluid collection at the site of surgery;
Attacks of dizziness or vertigo;
Tinnitus, which is a ringing or buzzing sound in the ear;
A taste disturbance; the nerve that gives taste sensation to the tongue also goes through the middle ear and might be injured during the surgery.
Numbness around the ear;
Reparative granuloma; this is the result of localized inflammation that can occur if the body rejects the implant. There may be other unforeseen complications that could occur with long term implantation that we cannot now predict.

Other Risks Associated with the Use of Cochlear Implants:
People with a cochlear implant: May hear sounds differently. Sound impressions from an implant differ from normal hearing, according to people who could hear before they became deaf. At first, users describe the sound as "mechanical", "technical", or "synthetic". This perception changes over time, and most users do not notice this artificial sound quality after a few weeks of cochlear implant use.

May lose residual hearing; The implant may destroy any remaining hearing in the implanted ear.

May have unknown and uncertain effects. The cochlear implant stimulates the nerves directly with electrical currents. Although this stimulation appears to be safe, the long term effect of these electrical currents on the nerves is unknown.

May not hear as well as others, who have had successful outcomes with their implants;

May not be able to understand language well. There is no test a person can take before surgery that will predict how well he or she will understand language after surgery;

May have to have it removed temporarily or permanently if an infection develops after the implant surgery. However, this is a rare complication.

May have their implant fail. In this situation, a person with an implant would need to have additional surgery to resolve this problem and would be exposed to the risks of surgery again;

May not be able to upgrade their implant when new external components become available. Implanted parts are usually compatible with improved external parts. That way, as advances in technology develop, one can upgrade his or her implant by changing only its external parts. In some cases, though, this won't work and the implant will need changing;

May not be able to have some medical examinations and treatments;

These treatments include:
MRI imaging: MRI is becoming a more routine diagnostic method for early detection of medical problems. Even being close to an MRI imaging unit will be dangerous because it may dislodge the implant or demagnetize its internal magnet. FDA has approved some implants, however, for some types of MRI studies done under controlled conditions.

Neurostimulation.

Electrical surgery.

Electroconvulsive therapy.

Ionic radiation therapy.

Will depend on batteries for hearing.

For some devices new or recharged batteries are needed every day.

May damage their implant.

Contact sports, automobile accidents, slips and falls, or other impacts near the ear can damage the implant.

This may mean needing a new implant and more surgery. It is unknown whether a new implant would work as well as the old one.

May find them expensive. Replacing damaged or lost parts may be expensive.Will have to use it for the rest of life. During a person's lifetime, the manufacturer of the cochlear implant could go out of business.

Whether a person will be able to get replacement parts or other customer service in the future is uncertain.

May have lifestyle changes because their implant will interact with the electronic environment.

An implant may Set off theft detection systems;

Set off metal detectors or other security systems;

Be affected by cellular phone users or other radio transmitters;

Have to be turned off during take offs and landings in aircraft;

Interact in unpredictable ways with other computer systems;

Will have to be careful of static electricity;

Static electricity may temporarily or permanently damage a cochlear implant.

It may be good practice to remove the processor and headset before contact with static generating materials such as children's plastic play equipment, TV screens, computer monitors, or synthetic fabric. For more details regarding how to deal with static electricity, contact the manufacturer or implant center.

Have less ability to hear both soft sounds and loud sounds without changing the sensitivity of the implant. The sensitivity of normal hearing is adjusted continuously by the brain, but the design of cochlear implants requires that a person manually change sensitivity setting of the device as the sound environment changes.May develop irritation where the external part rubs on the skin and have to remove it for a while.

Can't let the external parts get wet. Damage from water may be expensive to repair and the person may be without hearing until the implant is repaired. Thus, the person will need to remove the external parts of the device when bathing, showering, swimming, or participating in water sports. May hear strange sounds caused by its interaction with magnetic fields, like those near airport passenger screening machines.

2nd Part of Article

2009-04-03T04:01:00.001-07:00

British Member of Parliament Jack Ashley received a cochlear implant in 1994 at age 70 after 25 years of deafness, and reported that he has no problem speaking to people he knows one on one, even on the telephone, although he might have difficulty with a new voice or with a full of activity conversation, and still had to rely to some amount on lip-reading. He described the robotic sound of human voices perceived through the cochlear implant as "a croaking dalek with laryngitis". Even modern cochlear implants have at most 24 electrodes to put back the 16,000 delicate hair cells that are used for normal hearing. However, the sound superiority delivered by a cochlear implant is often good quality enough that many users do not have to rely on lip-reading. American radio host Rush Limbaugh, who has severe hearing difficulties, says that everything sounds normal apart from that he cannot decipher the melody of new music that he had not heard prior to becoming deaf.

Adults who have grown up deaf can find the implants ineffective or irritating. This relates to the specific pathology of deafness and the time frame. Adults who are born with normal hearing and who have had normal hearing for their early years and who have then progressively lost their hearing tend to have better outcomes than adults who were born deaf. This is due to the neural patterns laid down in the early years of life, which are crucially important to speech perception. Cochlear implants cannot overcome such a problem. Some who were orally educated and used amplifying hearing aids have been more successful with cochlear implants, as the perception of sound was maintained through use of the hearing aid.

Many individuals who use sign language believe they have no use for sound. Individuals who are deaf use sign language and an interpreter to communicate with those who use spoken languages, in the similar way that an individual who only speaks English but wants to meet with an individual, who only speaks French, would utilize an interpreter.

Children without a working auditory nerve may be helped with a cochlear implant, although the results may not be best. Patients without a feasible auditory nerve are usually identified during the candidacy process. Less than 1% of deaf individuals have a missing or damaged auditory nerve, which today can be treated with an auditory brainstem implant. Recent research has suggested that children and adults can advantage from bilateral cochlear implants in order to aid in sound localization and speech understanding.

Risks and disadvantages:

Some effects of implantation are irreversible; while the machine promises to provide new sound information for a recipient, the implantation process unavoidably results in damage to nerve cells within the cochlea, which often results in a permanent loss of most residual natural hearing. While fresh improvements in implant technology, and implantation techniques, assure to minimize such damage, the risk and extent of damage still varies.

In addition, while the machine can help the recipient improved hear and understand sounds in their environment, it is cleanly incapable of replicating the quality of sound processed by a natural cochlea. As a result, some recipients can only distinguish the difference between simple sounds, such as ringing phone bell and a doorbell, while others can clearly understand speech in quiet environments. The achievement rate depends on a variety of factors, including technology used and condition of the recipient's cochlea.

The FDA reports that cochlear implant recipients may be at higher risk for meningitis. A study of 4,265 American children, who received implants between 1997 to 2002, concluded that recipient children had a danger of pneumococcal meningitis more than 30 times greater than that for children in the general population. A later, UK-based, study found that while the incidence of meningitis in implanted adults was significantly higher than the general population, the occurrence in children was no different than the general population.

There are strict protocols in choosing candidates to avoid risks and disadvantages. Batteries of tests are performed to make the deCochlear Implants ion of candidacy easier. For instance, some patients suffer from deafness medial to the cochlea - typically acoustic neuronal. Implantation into the cochlea has a low success rate with these people as the artificial signal does not have a healthy nerve to travel along. With careful selection of candidates, the risks of implantation are minimized.

Ethical issues:

Discussions within the deaf community continue to fuel controversy and emotional personal debates about health, rights of the individual citizen, language, ethics, and the effects of the device on deaf society. For some in the deaf group of people, Cochlear Implants are an affront to their culture as they view it, is a minority threatened by the hearing majority. This has been a difficulty for the deaf community and goes back as far as the 18th century with the argument of manuals vs. orals. Another part of the controversy concerns the essential right of an individual to choose a language versus an individual as a young child having a form of communication and language chosen for them. In the history, many adults whose first language is sign language endured policies created by medical and educational governing bodies that enforced the use of spoken language and use of hearing aids on them. One argument made by those in the deaf community opposed to cochlear implants is that implantation of CI's in young children is just another form of mistreatment. In the past, deaf individuals have successfully advocated change to improve human rights for individuals, and they continue to work to supporter for change that will help children who are born with loss of hearing.

Cochlear implants for congenitally deaf children are often considered to be most effective when implanted at a young age, during the critical period in which the brain is still learning to understand sound. Hence they are implanted before the recipients can decide for themselves. Critics question the ethics of such invasive optional surgery on children. They point out that manufacturers and specialists have exaggerated the efficacy and downplayed the risks of a procedure that they stand to increase from. On the other hand, Andrew Solomon of the New York Times states that "Much National Association of the Deaf propaganda about the danger of implants is alarmist; some of it is positively inaccurate."

Much of the strongest objection to cochlear implants has come from the deaf community, which consists largely of pre-lingual deaf people whose first language is a signed language. Regardless of the fact that to be deaf is to lack the ability to hear, many individuals who are deaf and the deaf community do not share the view of deafness held by many hearing parents of deaf children, who regard deafness as a disability to be "fixed". Individuals who are deaf rejoice their diverse culture. On the other hand, many people feel that refusing to implant deaf children is unethical, comparable to refusal to treat any other handicap or disease that can be effectively alleviated. Many individuals who can hear or who have become deaf due to injury or illness are not comfortable with the thought of a child who is short of the sense most commonly associated with human language. Individuals who are deaf may feel that implants are just another form of mental and physical abuse in the long history of punishments, mistreatment, and pain they have had to endure.

The clash over these opposing models of deafness has angered since the 18th century, and cochlear implants are the latest in a history of medical interventions promising to turn a deaf child into a hearing child, or, more accurately, into a child with a mild or moderate hearing impairment.

Critics argue that the cochlear implant and the subsequent therapy often become the focus of the child's identity at the expense of a deaf identity and ease of communication in sign language. Measuring the child's success only by their mastery of hearing and speech will lead to a poor self-image as "disabled" (because the implants do not produce normal hearing) rather than having the healthy self-concept of a proud deaf person.

Some writers have noted that children with cochlear implants are more likely to be educated orally and without contact to sign language. Also, children with implants are often isolated from other deaf children and from sign language. Instead they are 'married' to a team of hearing experts who will monitor their cochlear implant and adjust the speech processor, at great expense. Children do not always receive support in the educational system to fulfill their needs as they may require special education environments and Educational Assistants. According to Johnston, cochlear implants have been one of the technological and social factors implicated in the decline of sign languages in the developed world. Some of the more extreme responses from deaf activists have labeled the widespread implantation of children as "cultural genocide". As cochlear implants began to be implanted into deaf children in the mid to late 1980s, the deaf community responded with protests in the US, UK, Germany, Finland, France and Australia.

Opposition continues today but is softening. As the trend for cochlear implants in children grows up, deaf-community advocates have tried to counter the "either or" formulation of oralism vs. manualism with a "both and" approach; some schools now are successfully integrating cochlear implants with sign language in their educational programs. However, some opponents of sign language education quarrel that the most successfully implanted children are those who are encouraged to listen and speak rather than overemphasize their visual sense. Significantly, deaf individuals have a high rate of illiteracy due to the phonetic nature of western writing systems; it is consideration that cultivating the auditory senses will help a hearing impaired child avoid this problem. However, others (mainly deaf people who have been educated in decades past) feel that the high levels of relative illiteracy are mainly due to profoundly deaf children being taught orally despite being sign language users and not being able to fully understand speech. Oral education in the past, though, was very much different from the approaches nowadays, which have the benefit of hearing with cochlear implants. Previous generations relied heavily on lip-reading. A fairly high percentage of today's implanted persons can hear well or have only reasonable hearing loss and, depending on the individual, do not depend on lip-reading at all.

Parents and children alike have been interviewed to discuss their opinions on cochlear implants. Many children discuss the fact that many of their parents never asked them or discussed the idea of a cochlear implant with them. While some discuss the fact that their parents asked them about it and discussed it with them and that made it better. Young adults seem to have the most horrible experiences mainly for cosmetic reasons but for some the cochlear implants just not work for them. If a child is placed into a mainstream setting it makes it difficult for them because they feel like they do not fit in with their peers and cannot fully identify with the deaf community. One interviewee in the Christiansen and Leigh study states “In high school it was the worst time for me with the cochlear implant because I was really trying to discover my identity with the cochlear implant. I never accepted my deafness. And the cochlear implant in some ways showed me that no matter what, the moment I take it off I’m deaf. I’ll never be hearing 24 hours.”

A 2007 study about attitudes of young, implanted people shows that although they are aware of the negative effects, their feelings about the implantation are overwhelmingly positive. None of the teenagers participating in the study critic-Cochlear implanted their parents for making the deCochlear Implants ion. They developed a positive identity and felt that they belonged to both the hearing and deaf worlds although only some of them use both spoken and sign language.

Common Myths and Misconceptions:

A lack of clarity on a seemingly confusing theme causes myths and misconceptions to arise. The term ‘Bionic Ear’ seems to allude to the idea that a cochlear implant will provide a cure for what nature did not provide. However, present technologies are not adequately advanced for cochlear implants to be considered a counterpart to a normal human ear.

The myth that a cochlear implant will heal deafness is the one that causes the most controversy among the deaf and hearing community, especially because numerous in the deaf community believe that their deafness is a gift and attempts to fix or cure deafness it is not considered respectful to the members of that community.

Another myth that may appear alarming to people is the thought that cochlear implants will mark an end of the deaf community. There is much discussion in the deaf community about its future, not only because of cochlear implants, but also because of the implications of genetic research for correcting hereditary deafness. This technology may in fact reduce the size of the deaf community; however one must also look at the idea that many deaf people are welcoming of those individuals that have had cochlear implantation. Many of the children who have received cochlear implants still go to schools for the deaf and as many articles have discussed school and other outside activities with other deaf students increase the reach of deaf culture because only 10% of deaf children have parents who are deaf. Proof of the close-knit relationship of the deaf community, even through the advancement of cochlear implants can be seen at Gallaudet University. Every year at Gallaudet they have been counting the number of students that are admitted with cochlear implants and for the past four years that they have been counting the number doubles. Even at the elementary school on Gallaudet's campus the inclusion of the thought of cochlear implants can be seen in the children's books as well as a doll known as "C.I” Joe. However, there are counterarguments to this myth and that is some deaf people believe that cochlear implant surgery on young deaf children will decrease the numbers of deaf people and the idea of a cochlear implant adds to the understanding as deaf being a disability. The only problem with this dispute is that even if a child has a cochlear implant that does not necessarily take them out of the deaf community as a whole. Many deaf people will fight the point that it will take more than an implant to make deaf identity go away.

Functionality:

The implant works by using the tonotopic organization of the basilar membrane of the inner ear. "Tonotopic organization", also referred to as a "frequency-to-place" mapping, is the way the sorts out different frequencies so that our brain can development that information. In a normal ear, sound vibrations in the air lead to resonant vibrations of the basilar membrane inside the cochlea. High-frequency sounds (i.e. high pitched sounds) do not pass very far along the membrane, but low frequency sounds pass beyond in. The movement of hair cells, located all along the basilar membrane, creates an electrical disturbance that can be picked up by the surrounding nerve cells. The brain is able to interpret the nerve activity to determine which area of the basilar membrane is resonating, and therefore what sound frequency is being heard.

In individuals with sensor neural hearing loss, hair cells are often fewer in number and damaged. Hair cell loss or absence may be caused by a genetic mutation or an illness such as meningitis. Hair cells may also be destroyed chemically by an ototoxic medication, or just damaged over time by excessively loud noises. The cochlear implant bypasses the hair cells and stimulates the cochlear nerves straight using electrical impulses. This allows the brain to interpret the frequency of sound as it would if the hair cells of the basilar membrane were functioning properly.

Processing:

Sound received by the microphone must after that be processed to determine how the electrodes should be activated. Filter-bank strategies use Fast Fourier Transforms to divide the signal into different frequency bands. The algorithm chooses a number of the strongest outputs from the filters, the exact number depending on the number of implanted electrodes and other features. These strategies highlight transmission of the spectral aspects of speech. Although coarse temporal information is presented, the fine timing aspects are as yet poorly perceived and this is the focal point of much current research.

Feature extraction strategies used features which are rare to all vowels. Each vowel has a fundamental frequency (the lowest frequency peak) and formants (peaks with higher frequencies). The pattern of the fundamental and formant frequencies is specific for different vowel sounds. These algorithms try to recognize the vowel and then emphasize its features. These strategies emphasize the transmission of spectral aspects of speech. Feature extraction strategies are no longer widely used.

Transmitter:

This is used to transmit the processed sound information over a radio frequency link to the internal portion of the device. Radio frequency is used so that no physical connection is needed, which reduces the chance of infection and pain. The transmitted attaches to the receiver using a magnet that holds through the skin.

Receiver:

This component receives directions from the speech processor by way of magnetic induction sent from the transmitter. (The receiver also receives its power through the transmission.) The receiver is also a sophisticated computer that translates the processed sound information and controls the electrical current sent to the electrodes in the cochlea. It is embedded in the skull at the back the ear.

Electrode array:

The electrode array is made from a type of silicone rubber, while the electrodes are platinum or a similarly highly conductive material. It is connected to the internal receiver on one end and inserted into the cochlea deeper in the skull. (The cochlea winds its way around the auditory nerve, which is ton topically organized just as the basilar membrane is). When an electrical current is routed to an intra-cochlear electrode, an electrical field is generated and auditory nerve fibers are stimulated. In the devices manufactured by Cochlear Ltd, two electrodes sit outside the cochlea and acting as grounds-- one is a ball electrode that sits beneath the skin, while the other is a plate on the device. This equates to 24 electrodes in the Cochlear-brand 'nucleus' device, 22 array electrodes within the cochlea and 2 extra-cochlear electrodes.

Speech processors:

Speech processors are the part of the cochlear implant that transforms the sounds picked up by the microphone into electronic signals capable of being transmitted to the internal receiver. The coding strategies programmed by the user's audiologist are stored in the processor, where it codes the sound accordingly. The signal produced by the speech processor is sent through the coil to the internal receiver, where it is picked up by radio signal and sent along the electrode array in the cochlea.

There are primarily two forms of speech processors available. The most common kind is called the "behind-the-ear" processor, or BTE. It is a small processor that is kept worn on the ear, typically together with the microphone. This is the kind of processor used by most adults and older children.

The other form is called a body-worn-processor. This is the kind used typically by younger children, whose ears are too small to properly fit the bulky BTE processor. The body worn processor is kept on the user's body, and a long wire extends up to the microphone earpiece to connect it with the processor. Users of the body worn processor have to find some creative way where to place the body worn processor. Some mothers place the processor on the child's back in a pocket sewn onto a T-shirt or onsite others use a harness that clips across the child's chest.

Programming the speech processor:

The cochlear implant must be programmed individually for each user. The programming is performed by an audiologist trained to work with cochlear implants. The audiologist sets the minimum and maximum current level outputs for each electrode in the array based on the user's reports of loudness. The audiologist also selects the appropriate speech processing strategy and program parameters for the user.

Scientific and technical advances:

Professor Graeme Clark A.C. of La Trobe University, Melbourne, Australia has developed a prototype "hi fi" cochlear implant featuring 50 electrodes. The increased number of electrodes is expected to enable users to perceive music and discern specific voices in noisy rooms.

Researchers at Northwestern University have used infrared light to directly stimulate the neurons in the inner ear of deaf guinea pigs while recording electrical activity in the inferior calicles, an area of the midbrain that acts as a bridge between the inner ear and the auditory cortex. The laser stimulation produced more pre-Cochlear Implants signals in that brain region than the electrical stimulation commonly used in cochlear implants. Laser stimulation is a promising technology for improving the auditory resolution of implants but further research using fiber optics to stimulate the neurons of the inner ear is required before products using the technology can be developed.

Cochlear implants are rarely used in ears that have a functional level of residual hearing. However, Electric Acoustic Stimulation (EAS) devices have been developed that combine a cochlear implant with a sound amplifying hearing aid. EAS devices have the potential to make cochlear implants suitable for many people with partial hearing loss. The sound amplifying component helps users to perceive lower frequency sounds through their residual natural hearing while the cochlear implant allows them to hear middle and higher frequency sounds. The combination enhances speech perception in noisy environments.

CONTINUE ON 3RD PAGE ... FOLLOW THE BLOG ARCHIVE

COCHLEAR IMPLANTS: HEAR THE WORLD

2009-03-16T06:11:00.000-07:00

A Cochlear Implant (in short “CI”) is a surgically implanted electronic device that provides a sense of sound to a person who is deeply deaf or severely hard of hearing. The cochlear implant is frequently referred to as a bionic ear. Unlike hearing aids, the cochlear implant does not amplify sound, but workings by directly stimulating any functioning auditory nerves inside the cochlea with an electric field. External components of the cochlear implant comprise a microphone, speech processor and an RF transducer or main headpiece coil. A secondary coil is implanted beneath the skull's skin and inductively coupled to the primary headpiece coil. The headpiece coil has an attraction by which it attaches to another attraction placed on the secondary coil often beside the cochlear implant. The implant communicates the incoming signal to the implanted electrodes in the cochlea. The speech processor permits an individual to regulate the sensitivity of the device. The implant gives recipients additional auditory information, which may include sound discrimination well enough to understand speech in calm environments. Post-implantation rehabilitative therapy is often serious to ensuring successful outcomes.

About 150,000 people worldwide have received cochlear implants, with recipients split almost evenly among children and adults. The huge majority are in developed countries due to the high cost of the device, surgery and post-implantation therapy. A little but growing segment of recipients have bilateral implants (one implant in each cochlea).

There is disagreement whether providing cochlear implants to children is ethically justifiable; renewing a century-old debate about models of deafness that often lowest point hearing parents of deaf children next to the Deaf community.

History:
The finding that electrical stimulation to the auditory system can create an awareness of sound occurred around 1790, when Alessandro Volta (the developer of the electric battery) sited metal rods in his own ears and connected them to a 50-volt circuit, experiencing a jolt and hearing a noise "like a thick boiling soup". Other experiments occurred sporadically, until electrical (sound-amplifying) hearing aids began to be developed in earnest in the 20th century.

The first direct stimulation of an audio nerve with an electrode was performed in the 1950s by the French-Algerian surgeons André Journo and Charles Eyras. They placed wires on nerves exposed during an operation, and reported that the patient heard sounds like "a roulette wheel" and "a cricket" when a current was applied.

In 1957, Journo and Eyras of France, William F. House of the House Ear Institute in Los Angeles, and Robin Michelson of the University of California, San Fran Cochlear Implants Co., all created and implanted single-channel cochlear devices in human volunteers, although Michelson is extensively credited with being the creator of the Cochlear Implant (3M Cochlear Implant), which is the majority used throughout the world.

Point Presentation on the Cochlear Implant:
Parallel to the developments in California, in the seventies there were two other groups, working on the development of the Cochlear Implant in Vienna, Austria and Melbourne, Australia. On December 16, 1977 Prof. Kurt Burien implanted the first patient worldwide that received a multichannel cochlear implant. The device has been developed by the Scientists Vineberg and Erwin Hochmair, who founded MED-EL, producer of hearing implants, in 1989. Burien K, Hochmair E, Hochmair-Decoyer IJ. Lesser MR (1979)

In December 1984, the Australian cochlear implant was approved by the United States Food and Drug Administration to be implanted into adults in the United States. In 1990 the FDA lowered the approved age for implantation to 2 years, then 18 months in 1998, and finally 12 months in 2002, although off label use has occurred in babies as young as 6 months in the United States and 4 months internationally.

Throughout the 1990s, the large external components which had been damaged strapped to the body grew smaller and smaller thanks to developments in miniature electronics. By 2006, most school-age children and adults used a small behind-the-ear (BTE) speech processor about the size of a power hearing aid. Younger children have small ears and might mishandle behind-the-ear speech processors; therefore, they often wear the sound processor on their hip in a pack or small harness, or wear the BTE's pinned to their collar, barrette or elsewhere.

On October 5, 2005, the first of 3 recipients was implanted with Cochlear's TIKI device, a totally implantable cochlear implant, in Melbourne, Australia. This was part of a research project conducted by Cochlear Ltd. and the University of Melbourne Department of Otolaryngology under the umbrella of CRC HEAR to be the first cochlear implant system capable of functioning for sustained periods with no external components. The system is capable of providing hearing via the TIKI device in standalone mode (invisible hearing), or via an external sound processor. Although these recipients continue to use their devices successfully today, it will be severial years before a commercial product becomes available.

Since hearing in two ears allows people to localize sounds and to hear better in noisy environments, bilateral (both ear) implants are currently being investigated and operated. Users generally report better hearing with two implants, and tests show that bilateral implant users are better at localizing sounds and hearing in noise. Nearly 3000 people worldwide are bilateral cochlear implant users, including 1600 children. As of 2006, the world's youngest recipient of a bilateral implant was just over 5 months old in Germany 2004.

Parts of the cochlear implant:
The implant is surgically placed under the skin behind the ear. The basic parts of the device include:

External:
A microphone which picks up sound from the environment

A speech processor which selectively filters sound to priorities audible speech and sends the electrical sound signals through a slim cable to the transmitter.

A transmitter, which is a coil held in position by a magnet placed behind the external ear, and transmits the processed sound signals to the internal device by electromagnetic induction,

Internal:
A receiver and stimulator secured in bone beneath the skin, which converts the signals into electric impulses and sends them through an internal cable to electrodes.

An array of up to 22 electrodes wound through the cochlea, which send the impulses to the nerves in the scalar tympani and then directly to the brain through the auditory nerve system.

Candidates:
There are a number of factors that decide the degree of success to expect from the operation and the device itself. Cochlear implant centers determine implant candidacy on an individual basis and take into account a person's hearing history, cause of hearing loss, amount of residual hearing, speech recognition ability, health status, and family commitment to aural habilitation/rehabilitation.

A Prime Candidate is described as:
Having severe to profound sensor neural hearing impairment in both ears
Having a functioning auditory nerve
Having lived at least a short amount of time without hearing (approximately 70+ decibel hearing loss, on averiage)
Having good speech, language, and communication skills, or in the case of infants and young children, having a family willing to work toward speech and language skills with therapy
Not benefitting enough from other kinds of hearing aids
Having no medical reason to avoid surgery
Living in or desiring to live in the "hearing world"
Having realistic expectations about results
Having the support of family and friends
Having appropriate services set up for post-cochlear implant aural rehabilitation (through a speech language pathologist, deaf educator, or auditory verbal therapist).

Type of hearing impairment:
People with gentle or moderate antenna neural hearing loss are generally not candidates for cochlear implantation. After the implant is put into position, sound no longer travels via the ear canal and middle ear but will be picked up by a microphone and sent through the device's speech processor to the implant's electrodes inside the cochlea. Thus, the majority candidates have been diagnosed with profound sensor neural hearing loss.

The presence of auditory nerve fibers is essential to the functioning of the device: if these are damaged to such a degree that they cannot receive electrical stimuli, the implant will not work. A small number of individuals with severe auditory neuropathy may also benefit from cochlear implants.

Age of recipient:
Post-lingual deaf adults and pre-lingual deaf children form two distinct groups of potential users of cochlear implants with different needs and outcomes. Those who have lost their hearing as adults were the first group to find cochlear implants useful, in regaining some comprehension of speech and other sounds. If an individual has been deaf for a long period of time, the brain may begin using the area of the brain used for hearing for other functions. If such a person receives a cochlear implant, the sounds can be very disorienting, and the brain often will struggle to readapt to sound.

The risk of surgery in the older patient must be considered against the improvement in quality of life. As the devices improve, particularly the sound processor hardware and software, the advantage is often judged to be worth the surgical risk, mainly for the newly deaf elderly patient. The other groups of customers are parents of children born deaf who want to ensure that their children grow up with good spoken language abilities. Research shows that congenitally deaf children who receive cochlear implants at a young age (less than 2 years) have better success with them than congenitally deaf children who first receive the implants at a later age, though the critical period for utilizing auditory information does not close completely until teenage years.

Number of Users:
It has been estimated in 2002 that around 10,000 children in the US and an additional 49,000 people worldwide have received Cochlear implants. By the end of 2008, the total number of cochlear implant recipients has grown to an estimated 150,000 worldwide.
Mexico had performed only 55 cochlear implant operations by the year 2000. China will be having 15,000 cochlear implant surgeries on children, which are being paid for by a Taiwanese philanthropist. There is anxiety that the follow-up services in China are not adequate to meet the needs of cochlear implanted children. The operation, post-implantation therapy and ongoing effects.

Cochlear implant as worn by user:
The device is surgically implanted under a general anesthetic, and the operation usually takes from 1½ to 5 hours. First a small area of the scalp directly behind the ear is shaven and cleaned. Then a small in Cochlear Implants ion is made in the skin just behind the ear and the surgeon drills into the mastoid bone and the inner ear where the electrode array is inserted into the cochlea. The patient normally goes home the same day as the surgery, although some cochlear implant recipients stay in the hospital for 1 to 2 days. It is considered outpatient surgery. As with every medical procedure, the surgery involves a certain amount of risk; in this case, the risks include skin infection, onset of tinnitus, damage to the vestibular system, and damage to facial nerves that can cause muscle weakness, or, in worst cases, disfiguring paralysis. There is also the danger of device failure, usually where the in Cochlear Implants ion does not cure properly. This occurs in 2% of cases and the device must be removed. The operation also may destroy any residual hearing the patient may have; as a result, some doctors advise single-ear implantation, saving the other ear in case a biological treatment becomes available in future.

After 1-4 weeks of curative (the wait is usually longer for children than adults), the implant is turned on or activated. Results are typically not immediate, and post-implantation therapy is necessary as well as time for the brain to adapt to hearing new sounds. In the case of congenitally deaf children, audio logical training and speech therapy typically continue for years, though infants can become age suitable in a matter of months. The participation of the child's family in working on spoken language development is considered to be even more significant than therapy. The family can aid development by participating actively in the child's therapy, making hearing and listening interesting, talking about objects and actions, and encouraging the child to make sounds and form of words.

In 2003, the CDC and FDA announced that children with cochlear implants are at a slightly increased danger of bacterial meningitis. Although this hazard is tiny, it is still 30 times higher than children in the general population, without proper vaccinations. Severial users, audiologists, and surgeons also statement that when there is an ear infection causing fluid in the middle ear, it can have an effect on the cochlear implant, leading to temporarily reduced hearing.

The implant has a few effects unrelated to hearing. Manufacturers have cautioned against scuba diving due to the pressures involved, but the depths found in standard recreational diving appear to be safe. The external components must be turned off and removed prior to swimming or showering. Some brands of cochlear implant are unsafe in areas with strong magnetic fields, and thus cannot be used with certain diagnostic tests such as Magnetic Resonance Imaging (MRI), but some are now FDA approved for use with certain strengths of MRI machine. Large amounts of static electricity can cause the device's memory to reset. For this reason, children with cochlear implants are also advised to avoid plastic playground slides. The electronic stimulation the implant creates appears to have a positive effect on the nerve tissue that surrounds it.

Cost:
In the United States, medical costs run from US$ 45,000 to $ 105,000; this includes evaluation, the surgery itself, hardware (device), hospitalization and rehabilitation. Some or all of this may be covered by health insurance. In the United Kingdom, the NHS (National Health Services) covers cochlear implants in full, as does Medicare in Australia. According to the US National Institute on Deafness and Other Communication Disorders, the estimated total cost is $ 60,000 per person implanted.

Efficacy:
A cochlear implant will not cure deafness or hearing impairment, but is a prosthetic substitute for hearing. Some recipients find them extremely effective, others somewhat effective and some feel overiall not as good as off with the implant than without. For people already functional in spoken language who lose their hearing, cochlear implants can be a great help in restoring functional comprehension of speech, especially if they have only missing their hearing for a short time. Individuals who have acquired deaf blindness (loss of hearing and vision combined) may find cochlear implants a radical improvement in their daily life. It may provide them with more information for safety, communication, equilibrium, orientation and mobility and promote interaction within their environment and with other people, reducing separation. Having more auditory information that they may be recognizable with may provide them independent gathering of information to become more independent.

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Sumo DM Hearing Aid for Deaf Peoples

2009-02-21T03:15:00.000-08:00

Features:
· More speech and audibility
· Freedom from Feedback
· Child – friendly design
· Super Powerful and reliable
· All the right accessories

People first:
We believe that it takes more then technology and audiology to create the best hearing instruments. That’s why we put the individual needs and wishes of peoples with hearing loss first in our development of new hearing care solutions.

Digital Super Power
Your child’s key to better opportunities!
As a parent, you want your child to have every opportunity to succeed. You want them to be able learn. And you want them to be able to communicate, so that they can grow, have fun and eventually forge their own path in life.

This journey demands the best possible hearing care available - an instrument that provides clear and consistent access to speech, every day of the week. If you have been waiting for and instrument like this you will be delighted to hear that Sumo DM has arrived.

Sumo DM satisfies the most fundamental needs of children with severs-to-profound hearing loss. It is the smallest, most advanced super power instrument in the world – and it turns the page on a new chapter of development for your child/

5 Great Benefits of Sumo DM!
Sumo DM offers a host of benefits designed to enhance your child’s speech language and auditory skills. It also supports a young and dynamic lifestyle.

Benefit 1.
More speech and audibility:
· Sophisticated digital sound processing enhances speech and controls unwelcome noise.
· Intelligent technology matches your child’s hearing loss with extreme precision

Benefit 2.
Freedom from feedback:
· A dynamic anti-feedback system eliminates irritating whistling sounds.
· Brushing hair, putting on a cap or getting a hug wont end in a sudden attack of whistling.
· Less feedback makes life easier for your child, family friends and teachers.

Benefit 3:
Child friendly design:
· Sumo DM is the world’s smallest digital super power hearing aid.
· The lightweight shell is practical and comfortable to wear.
· The status light lets caregivers know that your child is receiving the needed amplification.

Benefit 4:
Super Powerful – and reliable:
· Sumo DM is robust and reliable – so it won’t let your child down.
· High quality components make it extremely resilient to everyday wear and tear.
· A battery management system promises consistent power for longer periods.

Benefit 5:
All the right accessories:
· Compatibility with all the major FM Systems makes Sumo DM easy to use at school and at home.
· Innovative interlocking adaptor shoes prevent the receiver from falling off and being lost.
· Sumo DM works seamlessly with oticon’s advanced, digital lexis FM System.

Sumo DM
Child – focused technology:

More speech and audibility:
To develop good listening and language skills your child needs consistent access to the speech signal. Sumo DM uses advanced speech detection and noise management systems to control unwelcome noise and maintain the crucial dialogue between adults and child. And with major reserves of digital power, Sumo DM increases audibility to provide better overall sound quality.

A tailor made signal:
Sumo DM’s digital sound processing system customizes the signal in much the same way as a sound engineer would do in a recording studio. Matching your child’s hearing loss with great precision; Sumo DM provides extra support in areas where amplification can be of real benefit.

Freedom from feedback:
Feedback can be frustrating, not only for your child but also for people in the immediate vicinity. But with Sumo DM’s dynamic feedback cancellation system (DFCS) constantly on “red alert”, this irritating phenomenon is kept family under control, without reducing the overall volume.

Freedom to hug!
Children often experience feedback when brushing their hair, chewing their food or giving their parents a hug. Sumo DM attacks the problem head on using DFCS it constantly monitors the input and output signals, and if feedback seems imminent – the system neutralizes it with no reduction in gain.

More fun for the family:
Your child isn’t the only person to be affected by feedback; family and friends are probably also surprised by it from time to time. Life is more fun when hugs can be exchanged without the fear of feedback!

Child – friendly design:
Sumo DM’s child – friendly design combines durability with functionally, all in a slender, lightweight shell. Temper – resistant features include the battery door and the volume control, which can be disabled to prevent accidental changes.

Smart controls:
Sumo DM is extremely practical, from the volume control wheel that doubles as an on/off button to the 3-program control switch. The volume control and program switches are clearly marked – a bonus for both child and family.

Visible status light:
Sumo DM’s status light is unique among super power hearing aids. Showing “Power-on” and “Preferred Volume Control Level”, makes it easy for parents and caregivers to see that the child is receiving the desired amplification.

Super Powerful and reliable:
In Sumo DM, special attention has been paid to protecting the interior components in order to avoid moisture and temperature – related breakdowns. Whether children are indoors or outdoors, Sumo DM keeps them in close contact with their surroundings.

Built to last:
On the inside and on the outside Sumo DM is one of the most robust solutions available. Your child can play, do sports or other rough and rumble activities without having to worry about it breaking.

More power for longer:
Sumo DM is the result of child – focused engineering that succeeds in improving not only size but also performance. The unique receiver technology provides high and consistent power output with very low battery drain.

All the right accessories:
Children with severe –to –profound hearing loss frequently use FM Systems and DAI devices, and Sumo DM’s accessories program was developed with this in mind. It offers easy and secure integration with all standard systems and accessories.

Safe and secure:
Unique, family – interlocking adaptor shoes give your child the freedom to enjoy all sorts of activities at school and during their leisure time, without having to worry about losing valuable accessories.

The lexis FM System:
Oticon’s wireless lexis FM System gives your child on extra boost at school and at home. In noisy situations it transmits the teacher’s voice directly to the hearing aid, and when plugged directly into the television it allows the whole family to listen at normal volume levels.

Designed with children in mind:

Status Light:
Sumo DM is unique in that it includes a status light that flashes for power - up and when the preferred volume control level is reached. As an option that can be activated by your hearing care professional, it indicates that the instrument is ON and that the battery is working.

Temper – resistant features:
Sumo DM features a temper – resistant battery door plus the option to disable the volume control (yours hearing care professional can do this).

Interlocking FM & DAI:
Sumo DM is compatible with all wireless FM Systems and DIA devices. These interlock securely into the battery door.

Intelligent volume control with markings:
The intelligent digital volume control features distinct “start and end” positions. Smart, eight – channel technology allows full – range gain adjustments without the risk of feedback. Seating the volume control at the preferred level is easy with the preferred level beeps and light flashes.

3 – Positions switch:
This fully programmable switch is designed to support up to three listening programs to suit individual needs. Each position can be programmed to any of the followings.

M: Microphone Program
MT: Microphone + Telecoil Program
T: Telecoil Program
OFF: Optional Off Program
*FM available with auto – detect *