A procedure designed to improve hearing in adult humans has been used for the first time in the world to regain hearing in man's best friend.
University of Queensland and Royal Brisbane Hospital researchers have fitted a six-year-old Golden labrador called Barney with a bone-anchored hearing aid, a device used by people unable to wear conventional hearing aids.
Veterinary surgeon Sue Sommerlad and human audiologist Deborah Mackenzie worked together to fit Barney with the device.
The pair are now seeking $30,000 funding to extend the project to the next stage for further use in children and smaller animals.
The collaborative project between Ms Sommerlad, Head of Small Animal Surgery at the University of Queensland's School of Veterinary Science and Animal Production, and Ms Mackenzie, Director of Audiological Services at Royal Brisbane Hospital, arose from the desire to augment hearing in dogs which had become partially deaf as a result of chronic ear infection.
Ms Sommerlad said chronic infection of the middle and external ear was quite common, but if it did not respond to treatment, veterinarians sometimes had to consider removing the diseased ear canal.
"In such circumstances, veterinarians and owners face a dilemma - they need to cure the infection and the pain, but some hearing will be sacrificed," she said.
Ms Sommerlad said a dog with reduced hearing obviously posed a problem as it may not hear commands or warning sounds or approaching vehicles, and could therefore be a danger to itself and a worry for its owners.
"Some form of hearing aid appeared to be the solution, but it was apparent a conventional hearing aid would not work on a dog," she said.
Ms Sommerlad said she first considered a bone-anchored implant after discussing titanium implants for dental prostheses in dogs with University veterinary dental surgeon Gary Wilson. Bone-anchored hearing aids using titanium implants have been used successfully at Royal Brisbane Hospital to restore hearing to 20 adult patients unable to use conventional hearings aids for a variety of reasons.
The device works by transmitting sounds (vibrations) which are picked up by the hearing aid, via the titanium implant through the skull to the inner ear, where they are interpreted.
After attending a course for use of the procedure in humans, at Birmingham in the UK, Ms Sommerlad discussed the possibility of a veterinary application with Ms Mackenzie who had studied the system in Sweden.
Ms Mackenzie is also part of the team which had implanted these hearing aids in human patients at the Royal Brisbane Hospital.
They received support and encouragement from John Divitini of the Swedish dental technology group, Nobel Biocare, which manufactures the titanium implants and the hearing aids. They found the ideal patient in Barney, an abandoned Golden Labrador who was in poor condition, considerably under weight, and suffering chronic ear infection.
Audiological testing showed that Barney's hearing had already been severely affected by the chronic ear infection and that he needed surgery. Ms Sommerlad and Ms Mackenzie decided to try to improve his hearing with a bone-anchored hearing aid.
Ms Sommerlad, supervised by Ms Mackenzie, implanted the titanium fixture late last year, and recently attached the hearing aid.
"Audiological testing has shown that Barney has regained his hearing when wearing the hearing aid, but the really exciting part is he now responds to his name, his behavior has improved, and he can follow a voice," Ms Sommerlad said.
"In the beginning we wondered at times if we had chosen the right patient, but he's now become a lovely, placid dog and he seems to enjoy life so much more."
While Barney has become a favourite among UQ veterinary, and speech pathology and audiology students, he will have a loving home with the Sommerlad family once the project is complete. The team is now seeking further funding to enable research to be undertaken on the use of the technique in very young children and smaller animals.
Ms Mackenzie said the technique was currently limited by the thickness of the skull to which the fixtures could be attached.
"If we can devise a way of using bone-anchored hearing aids with very young deaf children, this could have important implications for enabling them to speak at a much earlier age," she said.
The "Barney" project has received important support from veterinary company representative John Lambert who supplied instrumentation for the surgery, and the Head of the University's School of Veterinary Science and Animal Production, Professor Keith Hughes.
Media: For further information contact Ms Sue Sommerlad on 07 3365 2123 or Ms Deborah Mackenzie, on 07 3253 5111.
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