Bionic eye fulfils far-sighted prediction

Dianne Ashworth's son would often ask her if she would ever be able to see him.

Ashworth, 54, started going blind 30 years ago when diagnosed with a hereditary condition, retinitis pigmentosa.

Her belief that technology would one day restore her sight prompted her to tell her eldest child this could be a possibility by the time he turned 30.

That son is now 28 and Ashworth's comments could prove prophetic.

The Victorian mother was implanted with a bionic eye prototype at the Royal Victorian Eye and Ear Hospital in May, which was switched on last month after she recovered from surgery.

To her delight and the excitement of researchers, Ashworth can now see flashes of light and shapes when scientists deliver electrical pulses to the device.

The Australian prototype - the first in the world to be implanted behind rather than in front of the retina - will be tested over the next 18 months by scientists from Melbourne's Bionics Institute.

A camera and vision processor could be hooked up to the 24-electrode prototype as early as October, said Bionics Institute deputy director Professor Peter Blamey.

The bionic eye device would ultimately restore enough vision for patients to navigate their way around, read large print and hopefully recognise faces.

Information obtained will help researchers refine two more sophisticated devices, with 98 and 1024 electrodes. These are scheduled to be implanted in the first patients next year and the year after, Blamey said.

The 24 electrodes in Ashworth's prototype are located in a silicon form, which is curved to fit inside the eye.

HOW IT WORKS
* A 24-electrode prototype device is implanted behind retina.
* A small wire links device to connector behind ear.
* The implant is connected to an external system in the lab.
* Researchers stimulate the implant from the lab.
* Feedback from patient will help researchers develop a vision processor to build images from flashes of light.
* An external camera is planned for the next stage of development.
* A wide-view implant with 98 electrodes and a high-acuity model with 1024 electrodes are in development, with patient tests planned.

- AAP