Cochlear implants: a truly revolutionary medical device
2022-06-24T11:04:00Z
life sciences
Introduction
The development of the cochlear implant – sometimes referred to as a ‘bionic ear’ – was a massive step forward for hearing technology and the field of otology when it was first introduced in the late 1970s. Providing an unprecedented solution to some of the most severe forms of deafness and hearing loss, cochlear implants take the almost science-fiction-like approach of ‘hacking’ around the body’s own hearing system by surgically implanting a device which sends audio information directly into the brain. Thanks to this tiny but mighty medical device, millions of children and adults experience a better quality of life through their access to the world of sound.
How does a cochlear implant work?
Hearing is the only sense that can be successfully replicated through a medical device. Unlike hearing aids which simply amplify sound, cochlear implants deliver sound signals directly to a person’s auditory nerve, effectively bypassing damaged portions of the ear which are impairing their hearing. The implant consists of an external processor that fits behind the ear to capture sound signals, and a receiver that is surgically implanted under the skin behind the ear. The receiver sends signals to electrodes implanted in the cochlea (inner ear). These signals stimulate the auditory nerve, directing the signals to the brain, where they are interpreted as sounds. The implant does not restore normal hearing and may take its user three to six months to learn to interpret the signals coming from their cochlear implant. With training, people learn to recognise warning signals, understand the sounds of their environment and comprehend speech, both in person and over the phone.
Where it began
The multi-channel cochlear implant which is commonplace today was pioneered by Australian Professor Graeme Clark, who successfully performed the world’s first cochlear implant operation at Melbourne’s Royal Victorian Eye and Ear Hospital in 1978. Clark had a keen interest in finding ways to improve, restore and even introduce hearing to patients. His work in ENT surgery, electronics and speech science played a large role in the development of the cochlear implant. On that momentous day in 1978 when his adult patient Rod Saunders heard his first words following the cochlear implant surgery, Professor Clark reported: “I was just so overcome I went into the next door laboratory and wept for joy.” He has been lauded nationally and internationally for his research.
Evolution of the cochlear implant
Following the excitement of that first successful implant four decades ago, Professor Clark further developed the cochlear implant into a 22-channel device. In 1985, the Nucleus 22 implant became the first commercially available multi-channel cochlear implant in the world. Since then, multiple iterations have come to market, boasting technological improvements that make each version more comfortable to wear and easier to use.
More sophisticated modern models are designed with more electrodes, which enable a wider range of pitch perceptions. Electrical current is also tightly controlled to provide a more detailed pitch. Today’s models even offer direct streaming capabilities with compatible smartphones, meaning recipients can stream phone calls, movies, and music directly to their sound processor, without needing an intermediate device like a phone clip. As of 2019, approximately 736,900 registered devices had been implanted worldwide, and that figure is projected to continue rising in the future. The World Health Organization projects that by 2030, nearly 2.5 billion people will have some degree of hearing loss, and at least 700 million (one in every ten people) will require hearing rehabilitation.
Who can benefit?
There is no upper or lower age limit on recipients for a cochlear implant: any person with a moderately severe to profound degree of hearing loss in the inner ear or cochlear may be a potential candidate. Babies as young as a few months old and adults in their late 90s have received successful implants. Research has shown that when children receive a cochlear implant – followed by rigorous therapy – before they are 18 months old, they are better equipped to hear and comprehend sound and music, and speak, than those who receive implants at an older age. In fact, studies show that children under 18 months of age may even develop language skills at a rate comparable to children with normal hearing.
Regardless of age, cochlear implants offer many benefits, including: ability to hear speech without needing visual cues, capacity to hear in a loud environment, recognition of environmental sounds, ability to detect where sounds are coming from, and the capacity to hear television programs, music and telephone conversations (although it’s worth noting that music is unfortunately not able to be enjoyed in the same way as a person with regular hearing, as the implant cannot capture pitch and timbre in the same manner). People with cochlear implants may also experience an improvement of symptoms such as tinnitus (ringing) in the implanted ear.
Hearing loss in the workplace
Currently, more than 1.5 billion people (nearly 20% of the global population) live with hearing loss around the world. It stands to reason that some of your colleagues may suffer from some degree of hearing loss, whether you are aware of it or not. It’s important to be mindful when communicating, to ensure everyone can hear and understand, and that everyone feels comfortable and included in all settings. Here are some tips for navigating hearing loss in the workplace:
- If you have a colleague with a hearing impairment and you are uncertain how to communicate with them, the best thing to do is ask them.
- If you yourself have a hearing impairment, let people know. Try to avoid the blanket statement “I’m deaf” and instead use specific examples so others can better understand how to communicate with you. For example, “I have trouble hearing conversation if there’s a lot of background noise or I can’t see your face.”
- When talking face to face with a colleague with hearing loss, ensure you have their attention first, such as by saying their name or stepping into their line of vision.
- Often a person with hearing loss will need to see your face during conversation, so make sure your face is well lit. For example, don’t stand in front of a window, where your face is in shadows. Avoid looking around, dropping your head or covering your face with your hand when talking.
- If someone needs to lip read, speak clearly but don’t exaggerate your lip and mouth movements. Pause from time to time to ensure they understand and use body language and expression as normal (a deadpan face makes understanding you more difficult).
- Rather than repeat a missed phrase word or word, try saying it another way.
- In a meeting scenario, distribute an agenda beforehand, repeat questions asked before answering, present information as visually as possible and make sure the speaker’s face is well lit.
- Don’t neglect a person with hearing loss and conversely, don’t focus on their disability by expressing sympathy or admiration. Move past their hearing impairment and focus on getting to know them as a person.