Artificial electronic retina restores hope to the blind … In the last ten years there has been great progress in the treatment of diseases of the retina, lining the inside of the eye and sending images to the brain through the optic nerve. The diseases of the retina are conditions where the center of vision in the brain and optic nerve are preserved, but the retina loses function because of the failed photoreceptors. A recent great invention will give hope to the blind – an artificial electronic retina.
Doctor dr. sc. Ratimir Lazić from the Special Hospital for Ophthalmology Svjetlost returned from the annual meeting of the American Society of Retinal Specialists held in San Francisco. There, he had the opportunity to talk a colleague Dr Mark Hamayun who had just become the president of the association. Dr Hamayun has constructed the first “electronic chip” or an electronic retina which can be implanted to people who have lost their sight due to a hereditary disease called retinopathy pigmentosa.
Because of the failed photoreceptors of the retina, people can not see although the function of the optic nerve and the vision center are preserved. The chip embedded in the background of the eye in a way takes over the function of the photoreceptors and stimulates the optic nerve. The electrical diodices generate electricity, and depending on which diodices are stimulated, shapes and contours are created and transmitted to the brain. The electronic chip can be stimulated in two ways – directly, by the image entering the eye, i.e. the photosensitive diodes, and indirectly – by wearing glasses incorporating a mini camera. The picture from the camera is transmitted wirelessly to the chip, which then stimulates the optic nerve with electric diodices.
Although the direct way is more natural, it requires full transparency of the cornea , the lens and the vitreous, because only then can the picture stimulate the diodices. When the picture is created via the camera, transparency is not important. The only approved chip currently is the indirect chip called the Argus II. Although the picture that the patient in this way gets is very modest (only contours and silhouettes are visiable), this represents a significant advancement in ophthalmology and contributes to the safety of movement of blind persons. For the first time, people with retinopathy pigmentosa could see.
Taken from: http://magazin.hrt.hr/