Oct 2018 Australian Financial Review
Cochlear is embarking on clinical trials of a fully implantable hearing device that it hopes will be the next big breakthrough in the world-leading technology that surgeon Graeme Clark pioneered in Melbourne four decades ago. The fully implantable hearing device should enable patients to hear 24 hours a day, whether they are sleeping, showering, swimming or even gardening in hot weather – a degree of functionality current implants can't deliver. That's because they rely on external sound processors and batteries to make the implanted hearing devices work properly and these have to be removed when sleeping or entering water.
The fully internal implant now being trialled includes a battery and sound processor. One patient in the clinical trial has already been implanted, tuned in and switched on at The Royal Victorian Eye and Ear Hospital in Melbourne. Robert Briggs, the surgeon leading the trial with Robert Cowan of the HEARing Co-operative Research Centre, hopes to recruit another 10 patients to try the experimental implants out over the next two years."It really is an amazing next step," Associate Professor Briggs said. "The hope is certainly that it will lead to a commercially available implantable device.” That could be years away. The conventional Cochlear device was a massive breakthrough when first implanted in a patient at the Eye and Ear because before that "it was not understood that you could restore hearing" in patients with profound hearing loss, Associate Professor Briggs said.
The fully implantable hearing device should enable patients to hear 24 hours a day
The first generation of the fully implantable device was implanted in three patients in 2005 and 2006 for a Phase 1 trial, but was only a qualified success. "Body noises" – the gurgling, sucking sounds familiar to viewers of science-fiction film portrayals of miniaturised people who go exploring inside a human body – interfered with the sound quality because the technology used in the internal microphones at the time wasn't sophisticated enough to be capable of cancelling out those sounds. The brain does a pretty good job of suppressing these sounds but when a microphone is inserted beneath the skin it is a bit like sticking your finger in your ear and crunching on potato chips at the same time, Jan Janssen, Cochlear's chief technology officer said. It makes the sound "a lot louder".
Even so, the three original recipients still have the internal implants today, Mr Janssen said. One, a young mother at the time, said it made her feel more secure knowing she could hear a fire alarm at night. And a retired man who likes gardening without the external implant in Melbourne's hot weather said that "now at least I know when I switch off my power tools”. Cochlear hopes vastly improved noise-cancelling microphone technology of the last decade has solved the "body noises" problem, and the latest microchips will enable the implants to download new software upgrades as they become available, like an iPhone or a Tesla electric vehicle.
Associate Professor Robert Briggs (left) the surgeon leading the trial hopes to recruit another 10 patients to try the experimental implants out over the next two years.
The internal battery can be recharged slowly by attaching the optional external sound processor, or "inductively" through the skin via a charger that sits behind the ear when a proper charge is needed. The Phase 2 trial will tell whether these improvements mean the patients implanted with the internal device can hear well enough to get by without the external sound processor all of the time, most of the time or whether they will just need it to have a conversation, Associate Professor Briggs said.
The development of the current version of the device and the clinical trial are absorbing "not the lion's share but a significant part" of Cochlear's annual research and development spend of 12 per cent of sales or just over $160 million. Cochlear continues to spend heavily on its conventional implants and sound processors as well. Last year it released an iPhone sound processor and later this year it will announce telehealth services attached to that device. Both Mr Janssen and Associate Professor Griggs said it would be a mistake for patients with profound hearing loss to try to wait for increased functionality and convenience of the fully implantable Cochlear device because the benefits of the existing devices are proven and delaying implantation can reduce those benefits. The increased size of the device means the operation to implant it takes an extra 90 minutes on top of the one-and-a-half-hour surgery for a conventional Cochlear implant, but the surgery is still straightforward, Associate Professor Briggs said.