Tag Archives: hearing

Cochlear implant electrodes improve hearing

Promising results have been reported from a world-first study of cochlear implant electrodes designed to stimulate hearing nerves and slowly release drugs into the inner ear.

HEARing Cooperative Research Centre (HEARing CRC) CEO Professor Robert Cowan said research using a cochlear implant electrode array that slowly releases anti-inflammatory drugs into the cochlear following implantation could lead to new benefits for cochlear implant users.

“The beauty of this approach is that it is based on use of the standard cochlear implant electrode array inserted into the inner ear that delivers sound sensations to the brain via the electrical stimulation of hearing nerve cells,” says Cowan. 

“The cochlear implant electrode array used in the research study was modified to slowly release a cortico-steroid after implantation.  This drug is intended to reduce inflammation and the growth of fibrous tissue around the electrode array triggered by the body’s immune response.”

After completing extensive biosafety studies, HEARing CRC researchers progressed to a study of the experimental electrode in ten adult patients, eight at the Royal Victorian Eye and Ear Hospital in Melbourne (RVEEH) and two at the Royal Institute for Deaf and Blind Children – Sydney Cochlear Implant Clinic (SCIC). 

 ENT surgeons Professor Rob Briggs and Professor Catherine Birman reported no compromise in surgical insertion characteristics with the experimental array.

Initial results confirm lower electrical impedance levels for the drug-eluting array patients, as compared with control groups from both clinics.  Impedance levels continue to remain lower 12 months post-implantation. 

“The suppression of the inflammatory reaction in the cochlear following electrode insertion is likely responsible for these lower impedance levels and may potentially contribute to preservation of an implant user’s residual hearing abilities when combined with slimmer electrode designs and newer surgical techniques,” Cowan explains. 

“Hearing preservation is important, as many candidates for cochlear implants have significant residual acoustic hearing, and want to be assured that they can use their residual acoustic hearing together with their cochlear implants.”

“Our hope is that this breakthrough will result in more people now considering cochlear implants as a viable way to manage their hearing loss”.

This drug-eluting electrode research has been made possible through the collaboration of Cochlear, RVEEH, and RIDBC-SCIC as members of the HEARing CRC, supported through the Commonwealth Governments CRC Programme.

“The HEARing CRC collaboration has contributed to commercial cochlear implant technologies that are now in world-wide use, as well as fitting technologies for both cochlear implants and hearing aids, helping to maintain Australia’s preeminent international standing in hearing research and service delivery,”  says Cowan. 

This article first appeared as a media release from the HEARing Cooperative Research Centre on 24 August 2016.

Leading the revolution

Cochlear implants have become synonymous with Australia’s innovation history. Inventor and surgeon Professor Graeme Clark put the first implant into patient Rod Saunders in 1978. Since then, Cochlear – the company that commercialised the cochlear implant – has been developing hearing products that improve the lives of hundreds of thousands of children and adults worldwide.

Today, Cochlear maintains its market competitiveness with aggressive R&D, research arrangements with 100 universities, and a strong leadership team. CRC partners have also helped maintain Cochlear’s position as world leader in implantable technology. For example, the Contour Advance Electrode array is now fitted to more cochlear implant patients worldwide than any other electrode design in the history of the field.

In return, the CRCs have gained access to a world-leading industry partner, and have helped contribute a value to Cochlear of approximately $120 million.

Cochlear’s Contour Advance Electrode is fitted to patients around the world.
Cochlear’s Contour Advance Electrode is fitted to patients around the world.

In April 2013, the CRC and Cochlear relationship entered a new era: the Australian Hearing Hub (AHH) at Macquarie University officially opened with an inaugural symposium managed by the HEARing CRC. The AHH
will provide the CRC with a Sydney base, as well as access to new facilities, including the world’s only magnetoencephalographic imager (MEG) that can be used with cochlear implant users to explore hearing centres in the brain, and how they adapt to cochlear implant hearing sensations. They have also developed a new 3D, real-world acoustic test environment.

“The potential impact for hearing health from this innovation worldwide is enormous.”

“This is a sensational example of what can be done through partnership,” says Associate Professor Jim Patrick, Chief Scientist at Cochlear Limited.


Name: Cochlear Limited

HQ: Sydney

R&D: $500 million in 5 years (to 2014)

Reach: Africa, Europe, USA, Middle East, Asia-Pacific as of 2012

At a glance: Listed in 1995, Cochlear Limited is one of Australia’s most celebrated advanced manufacturing success stories. It employs 2700 people in 25 countries with manufacturing sites in Sydney, Sweden, Belgium and the US.

– Paul Hendy