Health & Wellbeing

Retinal Prosthesis posts encouraging results in clinical trial

Retinal Prosthesis posts encouraging results in clinical trial
A clinical trial of the Argus II Retinal Prosthesis involving 30 patients has produced encouraging results
A clinical trial of the Argus II Retinal Prosthesis involving 30 patients has produced encouraging results
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A clinical trial of the Argus II Retinal Prosthesis involving 30 patients has produced encouraging results
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A clinical trial of the Argus II Retinal Prosthesis involving 30 patients has produced encouraging results
The Argus II Retinal Prosthesis designed for those suffering retinal pigmentosa
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The Argus II Retinal Prosthesis designed for those suffering retinal pigmentosa
The Argus II consists of a camera on the patient's glasses and an array of electrodes implanted on the patient's retina
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The Argus II consists of a camera on the patient's glasses and an array of electrodes implanted on the patient's retina
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After receiving European market approval for its Argus II Retinal Prosthesis in 2011, Second Sight has published interim results of an international clinical trial showing encouraging results in blind patients suffering severe retinitis pigmentosa (RP) - a group of genetic degenerative eye conditions that leads to incurable blindness.

The Argus II captures video images using a miniature camera housed in the patient's glasses and converts them into a series of small electrical pulses that are wirelessly transmitted to an array of electrodes on the surface of the retina. These pulses are designed to stimulate the retina's remaining cells which send messages along the optic nerve to the brain. The brain is then able to perceive patterns of light and dark spots corresponding to which electrodes have been stimulated.

The Argus II consists of a camera on the patient's glasses and an array of electrodes implanted on the patient's retina
The Argus II consists of a camera on the patient's glasses and an array of electrodes implanted on the patient's retina

The multicentered, long-term, controlled clinical trial involved 30 patients who were implanted with the Argus II Retinal Prosthesis, which is the only retinal prosthesis in the world so far approved for sale in Europe. The patients' progress was followed for periods of between six months and 2.7 years and they underwent a series of visual acuity tests performed using computer monitors - square localization, direction of motion and grating visual acuity. The patients were also given two types of real-world orientation and mobility (O&M) tests. These involved finding a door across a room and following a white line on the floor.

Results published in the journal Ophthalmology indicate significant improvements in the O&M tasks, as well as improvements of 96 percent in object localization, 57 percent in motion discrimination, and 23 percent in the discrimination of oriented gratings.

Second Sight says the results demonstrate the reliability and efficacy of the Argus II and that the safety profile of the prosthesis is comparable to other ophthalmic devices and procedures.

"The Argus II can, quite simply, help the blind see," said Dr. Stanislao Rizzo, Director of the U.O. Chirurgia Oftalmica, Azienda Ospedaliero Universitaria Pisana of Pisa, who on October 29, 2011, became the first surgeon to implant Argus II following European market approval. "Having an approved device backed by significant clinical data is cause for great hope among those patients suffering from RP. There is finally a real solution that means that their vision can be partially restored, safely."

Source: Second Sight

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yinfu99
I'm wondering why they don't just construct a prosthetic eyeball. I mean the whole thing. Using today's tech it seems quite feasible. With the ability to generate synthetic materials that are bio-friendly, to hook up nerves and neurons via the existing connections in the eye socket. The ability to interface with the brain with the parts of the synthetic eye for focusing, and auto adjusting, etc for lighting situations seems within the realm of do-able. In stead of trying to work with damaged/non working eyes with little to no chance of sight, put in a new synthetic one. Once in the person can be trained to use them, to interpret signals, to refine programming so actual sight is created. The energy for the internal eye movements can be tapped from the body itself for the usage is minimal.