The goal is to develop a micro-electronic device that consists of a multiple artificial retinal chip set and implant it in the eye to allow patients suffering from age-related macular degeneration or retinitis pigmentosa to see images. A research agreement signed today should help speed development.(http://www.energy.gov/engine/content.do?PUBLIC_ID=16769&BT_CODE=PR_PRESSRELEASES&TT_CODE=PRESSRELEASE)
"DOE's commitment to this effort is significant because it pools the tremendous resources of ORNL and Argonne, Lawrence Livermore, Los Alamos and Sandia national laboratories," said Eli Greenbaum, who leads the project for ORNL. "The labs offer impressive capabilities in the physical sciences and engineering, as well as unique facilities."
ORNL has several roles in the project, including developing concepts for electrodes, developing advanced instrumentation to evaluate the performance of the electrodes, and studying long-term operational stability of the micro-electrode arrays. This array would perform the function of normal photoreceptor cells.
Challenges involved in designing and fabricating the electrode array are immense, Greenbaum noted, as the devices are tiny and must perform a complicated task. Researchers are exploring various materials, including metals, alloys and ceramics, all of which must be biologically compatible with the human eye and able to last a lifetime.
The current prototype retinal implant contains 16 electrodes, which provides 16-pixel resolution and allows patients to detect the presence or absence of light and recognize large objects. The goal is to develop a 1,000-electrode implant that would enable the patient to see images in black and white with higher resolution.
To accomplish that goal, researchers must develop better electrodes and fabrication techniques. ORNL's Zhiyu Hu and Thomas Thundat have proposed just that. With their system, electrodes are fabricated by using nano-particles and micro-machining techniques. Unlike with conventional methods, this technique can create complex three-dimensional electrode arrays in batches -- as opposed to individually, which is tedious and expensive. This technique's unique 3-D layout capability allows researchers to create electrodes that perfectly match the distinctive surface contour inside the eye.
"We must be able to create an electrode array that is mechanically reliable and will safely and effectively pass current to stimulate the underlying retinal neurons," Hu said.
Other ORNL researchers involved in the project are Charlene Sanders, Bill Bryan and James Klett, who are developing a special electrically conductive carbon fiber. The fibers feature proprietary coatings to enhance the current and to insulate them electrically. This allows for a large array of fibers in a very small space, Bryan said.
The team of researchers must also develop a sophisticated compact camera system that can capture the image of the visual scene, translate the image into a pattern that can be created by the electrode array and then wirelessly transmit the information to the intraocular prosthetic device.
"This is indeed a massive effort involving dozens of tasks, and each task has its own unique set of challenges," Greenbaum said. "But we have assembled some of the world's best researchers and, working together, we are poised to make advances in a number of disciplines with the final outcome being to improve the quality of life for millions of people."
This prospective cure for blindness applies only to people whose neural wiring from the eye to brain is intact but whose eyes lack photoreceptor activity.
The research and development agreement builds upon an effort announced in November 2002 in which DOE committed $9 million over three years to augment artificial retina research.
"The Department of Energy has led the way to many scientific breakthroughs, especially when several scientific disciplines combined to make a whole greater than the sum of the parts," Energy Secretary Spencer Abraham said. "This project is one such example where biology, physics and engineering have joined forces to deliver a capability that will enable blind people to see.
"This agreement between the DOE laboratories and the private sector will facilitate transfer of many aspects of DOE technology to a clinical device that has the potential of restoring sight to millions of blind individuals."
The artificial retina technology was featured today in Chicago at the department's "What's Next Expo," an event designed to showcase the newest most innovative scientific and technological advances to interest young people in pursuing careers in math and science.
The Energy Department's Office of Science plans to fund the artificial retina project at $20 million over the next three years. The department funds the project as part of its medical applications technology program. The National Institutes of Health and the National Science Foundation are also supporting the project.
ORNL is managed by UT-Battelle for the Department of Energy