Light-wave implant hope for deaf
Sunday, 23 November 2008
An implant which works by firing infrared light into the inner ear is being investigated by US researchers, reports BBC.
Nerves in the ear can be stimulated by light as well as sound and the team from Northwestern University, Illinois, is aiming to harness this.
Infrared light shone onto guinea pig nerve cells produced better results than standard cochlear implants, a report in New Scientist magazine said.
But UK charity RNID said a device for human use might take years to develop.
For some profoundly deaf patients, the development of cochlear implants in recent years has been an important change.
The system works by placing approximately 20 electrodes to directly stimulate the nerves in the inner ear, but it has its limitations, with users finding it hard to appreciate music or communicate in a noisy environment.
This is because there are as many as 3,000 "hair cells" in a healthy ear, contributing to a far more detailed interpretation of sound than the implant can provide.
Dr Claus-Peter Richter from Northwestern believes that an effect discovered by chance could hold the key to a better implant.
Surgeons who used lasers to perform a surgical procedure in the ear discovered that they were able to stimulate the nerve cells there to send an electrical message back to the brain.
Exactly why this happens is unclear, although Dr Richter believes that the heat that accompanies the light may be responsible.
This could be a major breakthrough, but we have to remember that even if that true, the time between demonstrating this and developing a device will be quite significant
Nerves in the ear can be stimulated by light as well as sound and the team from Northwestern University, Illinois, is aiming to harness this.
Infrared light shone onto guinea pig nerve cells produced better results than standard cochlear implants, a report in New Scientist magazine said.
But UK charity RNID said a device for human use might take years to develop.
For some profoundly deaf patients, the development of cochlear implants in recent years has been an important change.
The system works by placing approximately 20 electrodes to directly stimulate the nerves in the inner ear, but it has its limitations, with users finding it hard to appreciate music or communicate in a noisy environment.
This is because there are as many as 3,000 "hair cells" in a healthy ear, contributing to a far more detailed interpretation of sound than the implant can provide.
Dr Claus-Peter Richter from Northwestern believes that an effect discovered by chance could hold the key to a better implant.
Surgeons who used lasers to perform a surgical procedure in the ear discovered that they were able to stimulate the nerve cells there to send an electrical message back to the brain.
Exactly why this happens is unclear, although Dr Richter believes that the heat that accompanies the light may be responsible.
This could be a major breakthrough, but we have to remember that even if that true, the time between demonstrating this and developing a device will be quite significant