Artificial Retina with Micro Fabrication

An implantable artificial retina fabricated at Lawrence Livermore National Laboratory is bringing sight to the blind.

“We’re talking about our progress and where we see the project going,” said Sat Pannu, who leads Livermore’s Center for Micro- and Nano-Technology, which has developed the microfabrication technology.

The project has many partners — including Second Sight Medical Products Inc., the Southern California company that has licensed the technology. Early, lower-resolution versions of the device allow people blinded for decades by the genetic eye disease Retinitis Pigmentosa or by age-related macular degeneration to see images, albeit fuzzy.

This is how it works: A miniature camera, which sits inside a pair of sunglasses, sends images wirelessly to a microprocessor worn on a patient’s belt. There it is converted to an electronic signal that is sent to a receiver on the eye, which sends the signal via a thin cable to a nanofabricated, watch-battery-size microelectrode array that is surgically tacked onto the retina. The array then emits pulses to the optic nerve, which sends a signal to the brain for processing.
The camera allows patients to zoom in and adjust the contrast of an image, Pannu said.

The project is led by Mark Humayun, a surgeon with a doctorate in biomedical engineering, at the Doheny Eye Institute at the University of Southern California. The lead laboratory is Oak Ridge National Lab in Tennessee.

Pannu, who has worked on the project since 2003, is turning again to the Department of Energy as well as the National Institutes of Health for the cash it would take to continue development through the highest-resolution version.

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Idiopathic Intracranial Hypertension May Cause Vision Loss

Idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is an unexplained buildup of fluid in the brain that pushes on the optic nerve, often causing headaches, vision loss, or even blindness. Some people with the condition may report visual problems, nausea, and tinnitus.

Interestingly, the majority of patients who develop pseudotumor cerebri are obese, although the link is not well understood. Dr. Steve Roach, chief of neurology and vice chair of pediatrics at Nationwide Children's Hospital in Columbus, Ohio is part of a team of doctors who opened up the first center dedicated to treating children with pseudotumor cerebri.

IIH can be controlled by weight loss and medication. To slow the loss of vision, a procedure called optic nerve fenestration can be done; which leaves a small window in the sheath of the optic nerve to release pressure.

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Systems To Help Blind See Again

Venture Capital Dispatch blog of the Wall Street Journal reported that two companies are working on vision systems to help some blind people see again.

Second Sight Medical Products, Inc. based in Sylmar, Calif. is developing special eyeglasses that transmit pictures to a receiver embedded on the retina. The images are transferred by the optic nerve to the brain. The device is targeted to patients who have lost most of their vision as a result of retinal degeneration and whose nerve connections are still intact.

Israel's Nano Retina Inc. is also developing a similar device. The devices are priced from $50,000 to $100,000. Both companies are now working with insurance companies to have them pick up the costs for patients in need of such devices.

A third company, Optobionics Corp is pursuing a trickier and more costly approach: restoring function to the damaged retina by using the device to stimulate the rods and cones, rather than using the system as an adjunct to the retina. They are looking for funds to enter Phase III trials.

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• Trial of human retinal implants quite successful (news.cnet.com)
• Two high-tech approaches to restoring sight (healthzone.ca)
• Technology Behind Second Sight Retinal Prosthesis (medgadget.com)

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