17 April 2017 - PROFESSOR GRAEME CLARK

PROFESSOR GRAEME CLARK

G'day folks,

Welcome to some background on a famous Australian scientist and inventor. One of our most distinguished alumni in the field of Otolaryngology is Professor Graeme Milbourne Clark, foundation Professor of Otolaryngology at the University of Melbourne and pioneer of the multiple-channel cochlear implant, the ‘bionic ear’. 

MB BS 1958 MSurgery 1969 Ph D Med 1970 MD 1989 FRCS (Edinburgh) FRCS (England) FRACS Hon MD (Hanover) Hon MD (Sydney) Hon DSc (Wollongong) Hon DEng (CYC Taiwan) Hon LLD (Monash) Hon FAudSA Hon FRCS (England) 

Professor Graeme Clark pioneered the multiple-channel cochlear implant which has brought hearing and speech understanding to tens of thousands of people with severe-to-profound hearing loss in more than 80 countries.

Graeme Clark graduated from Medicine at the University of Sydney in 1958 and became Resident Medical Officer at the Royal Prince Alfred Hospital (RPAH), Sydney. In 1960, he also became Lecturer in Anatomy in the Faculty of Medicine. By 1961, he had graduated to being Registrar in Neurosurgery and Otolaryngology at RPAH. He went to London in 1962 and was appointed Senior House Surgeon of the Royal National Ear Nose and Throat Hospital in London. He remained in England for four years, working at Bristol General Hospital and the Royal Victorian Eye and Ear Hospital. 

When he returned to Australia, Graeme first went to the Alfred Hospital in Melbourne, where he was the first Assistant Ear, Nose and Throat (ENT) surgeon, later becoming Senior Honorary ENT Surgeon. In 1967, he again lectured at the University of Sydney, this time in physiology. In 1969, he served as a Senior Research Officer of the National Health and Medical Research Council of Australia. 

Graeme became the foundation Professor of Otolaryngology at the University of Melbourne in 1970, retiring from that position in 2004, when he was made Honorary Laureate Professorial Fellow at the University and became full-time Director of the Bionic Ear Institute. 

Graeme had commenced basic research on electrical stimulation of the auditory nerve fibres at the University of Sydney in 1967. His research showed that multiple-channel (electrode) stimulation rather than a single-channel cochlear implant would be required for the management of a severe-to-profound hearing loss. Since 1970, Graeme has led the research on electrical stimulation of the auditory nerves in the Department of Otolaryngology at the University of Melbourne and the Bionic Ear Institute. 

This research has demonstrated that a multiple-channel cochlear implant can provide significant understanding of speech for severely-to-profoundly deaf children and adults and enable near normal speech for deaf children through electrical stimulation of the hearing nerves in the cochlea. The research also demonstrated that bilateral and bimodal cochlear implants can enable people with hearing aids and implants to localise sound and hear more effectively in a noisy environment. In a series of studies on experimental animals, he showed that a multiple-channel cochlear implant was safe, with minimal risk of meningitis from middle ear infection, if a fibrous tissue sheath was produced around a single-component multiple-electrode array and this was facilitated with a fascial graft.

It was not previously thought possible to provide speech understanding with a small number of electrodes, as the cochlea (inner ear) is innervated by 10,000 to 20,000 neurons in a complex manner. However, the multiple-channel cochlear implant resulting from the discoveries of Graeme and his co-workers is the first sensori-neural prosthesis to effectively and safely bring electronic technology into a direct physiological relationship with the central nervous system and human consciousness. Graeme also established the surgical and audiological principles that are the basis for its regular clinical use. 

A month after Graeme and his team operated on Rod Saunders to implant the University of Melbourne’s first bionic ear, they asked Saunders to return so they could see whether the surgery had worked and how they could help him understand speech. When they tested him with an electric current, all Saunders could hear was the hissing sound frequently experienced by deaf people. Finally, just before the third hearing test, they discovered a fault in the test equipment, which could account for the lack of results. 

Below is an excerpt from Sounds of Silence, describing the third appointment with Rod Saunders:

At the second test session I was eager to find out whether Rod could recognise the voicing and rhythm of speech. To test for these skills, we used the computer to play tunes through the implant. The first was the then national anthem, “God Save the Queen”. Our answer came immediately as Rod stood to attention, disconnecting some of his leads as he did so. It was good to have selected a patient with a sense of humour. Then Jo suggested, “Why not test him with Waltzing Matilda?” Rod had no trouble with that one either. He could recognise the songs he knew, but could he hum the tune of a song that had come out after he went deaf? We found that he could, which was very encouraging.

His work to develop the multiple-channel cochlear implant and take it through to commercial reality took 18 years, from 1967 to 1985, and is outlined in the History of the Cochlear Implant. The cochlear implant originally developed by the Melbourne research team and manufactured by the Australian company Cochlear Limited has held up to 80 per cent of the world market over the last 20 years. 

In addition to this research, Graeme has played a key role in the development of the Automatic Brainwave Audiometer, the first method for objective accurate measurement of hearing thresholds for low and high frequencies in infants and young children, and the Tickle Talker™, a device enabling deaf children to understand speech through electro-tactile stimulation of the nerves of the fingers. 

Graeme was awarded the AC (Companion of the Order of Australia), Australia’s highest civil honour, for services to medicine and to science through innovative research to further the development of cochlear implant technology for worldwide benefit in 2004. 

In 2005, he received the Excellence in Surgery Award from the Royal Australasian College of Surgeons which recognises the highest level of surgical achievement by world standards, advanced innovation in the field, continued quality and worth of the innovation, and the highest standard of ethics. He received the A Charles Holland Foundation International Prize for fundamental contributions to the progress of knowledge in audiology/otology, at the XVIII World Congress of the International Federation of Otorhinolaryngological Societies in Rome. He received the Royal College of Surgeons of Edinburgh Medal for outstanding contributions to medicine at the Quincentenary Ceremony for the Presentation of Diplomas. 

Graeme also received the Prime Minister’s Prize for Science, Australia’s pre-eminent award for excellence in science, recognising outstanding achievement by Australians in science and technology to promote human welfare in 2004. He was elected a Fellow of the Royal Society for his contribution to science, both in fundamental research resulting in greater understanding, and in leading and directing scientific and technological progress in industry and research establishments. He was elected an Honorary Fellow of The Royal College of Surgeons of England, awarded for outstanding achievement in medicine. He was elected a Fellow of the Australian Acoustical Society for notable contribution to the science and practice of acoustics, and received the Doctorate of Laws honoris causa from Monash University, its highest honour. 

In 2003, Graeme was elected an Honorary Fellow of the Royal Society of Medicine in London for exceptional distinction, with recipients drawn from across the world and from a wide range of endeavours, particularly in the medical sciences. He received the Doctorate of Engineering honoris causa from Chung Yuan Christian University in Taiwan. 

In 2002, Graeme was elected an Honorary Member of the American Otological Society. He received the Doctorate of Science honoris causa from the University of Wollongong, Australia. In 1998, he was elected Fellow of both the Australian Academy of Science and the Australian Academy of Technological Sciences and Engineering. 

Graeme has received Honorary Doctorate of Medicine degrees from the University of Sydney and the Medizinische Hochschule, Hanover along with many other awards and prizes.

 Clancy's comment: A great Australian. A great human. Not many people make such a large contribution to their fellow man. Graeme Clarke has altered countless lives. Well done! Love ya work!

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4 January 2015 - HEARING LOSS

HEARING LOSS

G'day  folks,

No doubt many of you suffer from hearing loss, or know someone who does. I sure do, and it can be very frustrating. Here are some of the causes of hearing loss.

There are two main types of hearing loss. Conductive hearing loss develops when something — congestion from a bad cold, an ear infection, a perforated eardrum — blocks sound signals from reaching the brain. Sometimes only one ear is affected, and once the problem is corrected, hearing usually returns to normal.

Far more serious is sensorineural hearing loss, which usually occurs in both ears and is triggered by loud noise as well as aging. Most people gradually lose some hearing as they get older.

 Conductive hearing loss — which often can be corrected

1. Earwax buildup

This waxy substance, secreted by glands near the ear canal, prevents harmful substances — germs, dust and dirt — from reaching the ear drum. Too little wax and your ears are dry, itchy and a breeding ground for infection. Too much can lead to painful earaches and hearing loss, and, in some cases, tinnitus (a ringing in the ears).

What to do: Usually, wax moves naturally to the tip of the canal, where it can be safely wiped away with a washcloth. If this doesn't happen, your doctor can remove it. Don't try to do it yourself with a cotton swab, pencil or the tip of your glasses. You may push it deeper or puncture your eardrum.

2. Perforated eardrum

Infection, explosive noise near the ear, quick changes in air pressure, as well as poking around with a cotton swab, can puncture the thin tissue that separates the outer from the middle ear, leading to pain and temporary hearing loss.

What to do: Although a punctured eardrum usually heals on its own in about two months, it's best to have your ear checked by an otolaryngologist — an ENT doctor who specializes in treating the ear, nose and throat. Meanwhile, keep the ears dry and use warm compresses and over-the-counter medications to relieve pain.

3. Ear infection

Though far more common in the preschool set, ear infections because of bacteria or viruses can follow a bout with allergies or the common cold in adults, too. If the eustachian tube, which connects the ear to the throat, is blocked by swelling and inflammation, fluid buildup becomes a breeding ground for infection. The result: ear congestion, pressure, pain, fever or temporary hearing loss.

What to do: Infections usually clear in a few days. A warm compress and over-the-counter pain medications and decongestants can help. If you have fever or severe pain, call your doctor. You may need antibiotics.

 Sensorineural hearing loss — usually permanent but often preventable

4. Listening to music with ear buds

Since ear buds don't block outside sounds, listeners often ramp up the volume for hours at a time. But these ubiquitous gadgets amplify sounds so successfully that it can top 100 decibels, loud enough to cause damage in only 15 minutes. "Anything over 85 decibels is potentially damaging," says Michael D. Seidman, M.D., director of otologic and neurotologic surgery at the Henry Ford Health System in Detroit.

What to do: Since many new ear buds come with volume control, toss your old ones and buy ones that do. If the person sitting next to you can hear the music, it's too loud. Music headphones are even easier on the ears, but remember to keep the volume low, says Seidman, author of Save Your Hearing Now.

5. All those crazy-loud football games and rock concerts

Noise is noise, whether it comes from a rock concert, a leaf blower or a stadium full of football-crazy fans. "Even hair dryers can reach 90 decibels," Seidman says. While a single incident of explosive sound — such as fireworks or a jackhammer — can lead to hearing loss, more often it's caused by day-to-day exposure over an extended period of time. If you keep going to concerts, games and noisy restaurants, the very delicate hair cells in the inner ear become worn down, causing hearing problems. "The loss is cumulative," Seidman says. "Once hair cells are damaged, they're not replaceable."

What to do: Carry ear plugs everywhere. Foam or wax earplugs block out more noise than molded ones, or you can have earplugs custom-fitted. Never stuff cotton balls in your ears since that can lead to impacted wax and infection. Give your ears a break: Whenever you're in a noisy venue, find a quiet place to rest your ears for a few minutes. Invest in a pair of noise-canceling headphones to use when mowing the lawn or doing other noisy chores. And consider easing up on the hard-rock concerts.

6. Tipping the scale

Being overweight — especially if those extra pounds are around your belly — is also a risk factor. Researchers at Boston's Brigham and Women's Hospital followed more than 68,000 women in the Harvard Nurses' Health Study II and found that those who had more body fat and larger waists reported more hearing problems than those of normal weight.

What you can do: Get moving. Researchers found that walking for as little as two hours a week cut the risk of hearing loss by 15 percent compared with those who walked less than one hour per week. "We suspect that obesity affects blood flow to the inner ear, compromising hearing, while physical activity may improve blood flow and help protect the ear," says lead researcher Sharon G. Curhan, M.D.

7. Diabetes

If you have diabetes, you're twice as likely to develop hearing loss as those with normal blood sugar levels. Those with prediabetes face a 30 percent greater risk. High glucose levels are risk factors for heart disease and researchers suspect that the same destructive action is at work on the nerves and blood vessels in the inner ear.

What to do: If you have diabetes, see an ENT or audiologist for a hearing screening. To combat glucose overload, be sure to exercise regularly; cut back on highly processed foods, opting instead for fish, vegetables, fruit and whole grains.

 8. Sleep apnea

A study of 13,967 people released last spring by the Albany Medical Center in New York found that those with sleep apnea — a stop-and-start breathing disorder — also had an increased risk of hearing impairment. While the connection between sleep apnea and heart disease has been known, this is the first time a link was also made to hearing loss.

What to do: Suspect sleep apnea? See your primary care physician, who may refer you to a sleep specialist. Various lifestyle changes and devices can open up a blocked airway. Make sure to also get your hearing checked by a professional.

9. Not wearing a hearing aid when you need one

Although not wearing a hearing aid won't cause hearing loss, there is some evidence that wearing an aid when you need one may help protect the hearing you have left. 

Unfortunately, only 1 out of 5 people who could benefit from a hearing aid wear one. "Most delay several years before accepting they have a problem and doing something about it," says Brad Stach, an audiologist at the Henry Ford Health System. Some people may not realize they have a problem. Others believe waiting won't cause any harm; still others are simply embarrassed to admit they can't hear well. But if you don't wear a hearing aid when you need one, or only wear it some of the time, you can lose the ability to process sounds.

What to do: "Your brain devotes a lot of resources toward hearing well," says Lin. "When words are garbled, it has to work harder to hear at the expense of other functions." Not wearing a hearing aid is also a safety concern, since hearing loss has been linked to falls, social isolation, depression, even dementia. So remind yourself that needing help with hearing is no different than needing glasses to read. Ask your doctor to check your hearing regularly and if necessary refer you to an ENT or audiologist who can diagnose the extent of hearing loss and suggest aids or assisted devices that can help.

Clancy's comment: Hope this has helped.

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