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A brain implant for restoring sight will enter clinical trials

Eric Selby poses with Second Sight's Argus II fitted in his right eye, which enables him to detect light.

Second Sight, the company that created the first artificial retina for people with a certain form of blindness, is now testing a brain implant called Orion, according to MIT Technology Review. The USFDA has conditionally approved a clinical trial of the technology, and the company plans to start enrolling patients for the trial implants in October.

How it works: Electrodes send electrical pulses to the brain's visual cortex, which registers the information as patterns of light. (Typically the visual cortex receives input from the retina).

The older device, Argus II, used a camera mounted on glasses that sent images to a chip implanted in the eye near the retina, which then sent electrical pulses to the brain to process the information. "In some types of blindness, the optic nerve is damaged so you have to go downstream. With the Orion, we're essentially replacing the eye and the optic nerve completely," Robert Greenberg, board chair of Second Sight told Technology Review.

Who it works for: Argus II could only help patients who were blind due to the disease retinitis pigmentosa. Second Sight estimates 400,000 such patients around the world are eligible for the device, but they have only sold 250 to date. The company estimates 6 million people worldwide who could be helped by their new technology. "Anyone who had vision but has lost it from almost any cause could potentially be helped by the Orion technology," Greenberg said.

Risks: The new technology would require a more invasive surgery, which comes with a higher risk of infections or seizures.