Device gives sight back to three blind people

A GROUND-BREAKING retinal implant has allowed three blind patients to see shapes and objects for the first time since they lost their sight to an inherited disease.

Before having the device fitted, each had a limited ability to perceive bright light but were completely unable to recognise shapes.

Within days of undergoing surgery, all three could locate objects placed on a table, including a cup, a saucer and different geometric shapes.

One patient was able to walk around a room with confidence, tell the time from a clock face, distinguish between subtle shades of grey and even read his own name.

A British eye expert commenting on the German breakthrough said it had turned science fiction to fact.

Two men and one woman aged 40, 44 and 38 took part in the pilot study testing the device developed by Retina Implant AG, a medical technology company in Reutlingen, Germany.

All had the inherited condition retinitis pigmentosa, which gradually destroys the light-sensitive retina at the back of the eye eventually leading to blindness.

After first becoming affected in early childhood, each of the patients had lost the ability to read at least five years before undergoing surgery.

The implant is fitted beneath the retina and consists of a three millimetre-square array of 1,500 light sensors.

Each “photodiode” delivers a pulsed electrical signal to adjoining groups of nerve cells, sending a message to the brain.

A power supply unit is connected to the device by means of a cable passed through the skin.

Details of the trial were published in the journal Proceedings of the Royal Society B.

Tests on the patients began just seven to nine days after their surgery.

Lead researcher Professor Eberhart Zrenner, director of the Institute for Ophthalmologic Research at the University Eye Hospital, Tuebingen, Germany, said: “The results provide strong evidence the visual functions of patients blinded by a hereditary retinal dystrophy can, in principle, be restored to a degree sufficient for use in daily life.”

Prof Zrenner and a group of colleagues founded Retina Implant AG in 2003 with the aim of developing the implant that could restore useful vision to the blind.

In total, 11 patients have now been fitted with the devices.

David Head, chief executive of the charity RP Fighting Blindness, said: “We’re still in the early days of this type of science. I have no doubt that over the years it will advance.”