Electronic retinal device may help blind people see

Surgeons at Moorfields Eye Hospital, UK recently carried out two successful operations to implant an artificial electronic retinal device into the eyes of two blind patients. They claim this is the first time that such devices have been implanted in Britain.

 

The aim of this trial which is part of an international Phase I clinical study, is to restore a basic level of useful vision, in the form of spots of light and shapes of light and dark, to people suffering severe blindness due to Retinitis Pigmentosa (RP), a group of inherited eye diseases that affects the retina.

 

The Argus II™ technology consists of a tiny camera and transmitter mounted in sunglasses, an implanted receiver, and an electrode-studded array that is tacked to the retina with a microtak the width of a human hair.

 

The camera on the glasses captures an image and sends the information to the video processor, which converts the image to an electronic signal and sends it to the transmitter on the sunglasses. The implanted receiver wirelessly receives this data and sends the signals through a tiny cable to the electrode array, stimulating it to emit electrical pulses. The pulses induce responses in the retina that travel through the optic nerve to the brain, which perceives patterns of light and dark spots corresponding to the electrodes stimulated - Patients learn to interpret the visual patterns produced into meaningful images.

 

The cable that runs from the glasses to a processing unit about the size of a SONY Walkman®, can run under clothing if desired whilst the processing unit can be held in the hand, attached to a belt or contained in a case or purse. A battery pack which can also be attached to a belt powers the entire device.

 

The operations were carried out by Mr Lyndon da Cruz, a consultant retinal surgeon and his team from the Vitreo Retinal department at Moorfields, under the supervision of American colleagues who developed the device with Second Sight in the US, who pioneered the Argus II implantation procedure.

 

Mr da Cruz said, "Moorfields is proud to have been one of only three sites in Europe chosen to be part of evolving this exciting new technology. The devices were implanted successfully in both patients and they are recovering well from the operations."

 

For more attend Printed Electronics USA 2008  also read an earlier article Contact lenses with circuits could be a platform for superhuman vision .