Rewiring the retina

HEADNOTE

National labs, universities, and at least one private company are exploring ways to help people blinded by retinal disease.

Hundreds of thousands of people in the U.S. have been blinded by macular degeneration,

retinitis pigmentosa, and other retinal diseases that damage the eyes' rods and cones. But while the rods and cones, the photoreceptors, might not be up to snuff in these people, the ganglion cells beneath them are often still working, patiently waiting to pass neural signals onto the brain via the optic nerve.

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The artificial retina will use a flexible, silicone-rubber-based implanted electrode such as this.

Doctors and engineers working on the government-sponsored Artificial Retina Project want to exploit those still-healthy ganglion cells, stimulating them directly, to return some degree of sight to those blinded by retinal disease. The Energy Department is providing $9 million in funding over three years for the project, and much of the R&D is being done at its national labs. The universities of Southern California and North Carolina State also play major roles, and second Sight, a private company in Sylmar, Calif., plans to commercialize the final product.