Driven by the concept of Moore’s law, which predicted that the number of transistors on integrated circuits doubles approximately every two years, the miniaturization of integrated circuit components has led to devices with exceedingly low power consumption and high sensitivity, enabling electrical signals to be sent to nerves . Bionic prostheses – devices that attempt to restore compromised biological functions by means of electronic tools – can be counted amongst the most exciting medical innovations. As Jamie Hartford describes: “Thanks to bionics, babies born deaf can hear, people who have lost their sight can see, people living with paralysis can walk, lower-limb amputees can run, and upper-limb amputees can type on a keyboard. Bionic medical devices make occurrences once considered miracles happen every day” .
This year, on January 29, history was made at the University of Michigan Kellogg Eye Center as two doctors successfully conducted surgeries to implant a bionic eye in a previously blind patient. The manufacturing company, Second Sight, recently received FDA approval on the Argus II Retinal Prosthesis system, which treats adults suffering from advanced retinitis pigmentosa, a rare genetic condition that results in little to no light perception in both eyes . This revolutionary technologyhas the power to augment the lives of more than 1 in 4,000 impacted by the illness. There are approximately 100,000 people suffering with this disability in the United States and 1.5 million individuals worldwide .
After Second Sight had invested twenty years in development and about $200 million in funding, the FDA approved the device under “humanitarian use” principles . The Argus II bionic eye is now being offered in thirteensites around the country for those with severe retinitis pigmentosa. While the cost of the implant is approximately $145,000, the Centers for Medicare and Medicaid services have recently approved the Argus II for payment in inpatient and outpatient care settings, nationally removing the last challenge in marketing the product. Brian Mech, vice president of business development at Second Sight, stated that this news would greatly facilitate access to the Argus II for Medicare beneficiaries regardless of the setting of care in which the system is provided [5,6].
The Argus II Retinal Prosthesis system is unique since it is the first device to be implanted in only one eye. The multi-piece system begins with a digital camera mounted on the eyeglasses, translates the images taken by the camera into data, and sends them via a wireless transmitter to a computer chip on the side of the eyeball. The chip on the eyeball activates an electrode array implanted at the back of the retina, which stimulates retinal cells to send information to the brain. The patient learns to interpret the new signals as they use the device more efficiently over time [7,8].
Although the retinal implant technology is able to improve the quality of life for patients who have lost functional vision, the implant cannot facilitate a recovery to 20/20 vision. The device currently enables patients to do simple but vital tasks including recognizing shapes, reading large letters (9 inches high), climbing stairs, walking through doors without a cane, and even detecting street signs. As such, bionic vision through the Argus II will seem closer to a grainy black and white film than an HD movie. Shawn Kelly, a scientist at the Carnegie Mellon University, said, “The electrode array is not finely tuned enough to produce the same detail of a functional human retina. More advanced technology will be necessary in order to convey colors as well as the type of visual resolution that we have in the center of our vision.” Higher quality implants and camera-free alternatives with retinal implants that look like computer chips are expected by 2017 .
While Second Sight is ahead in marketing its technology in America, the eye implant industry is not bereft of competition. New treatments involving gene therapy and retinal cell transplantation are also in clinical trials. A research group based at Stanford University is developing a system known as the Photovoltaic Retinal Prosthesis (PRP), which contains 5,000 pixels and will provide a much more detailed vision than alternatives. As opposed to the Argus II, the PRP uses a tiny video camera to capture images and convert them to near-infrared light. This light is then converted to electrical signals that are sent to the brain through the optic nerve. Furthermore, new techniques, approaches, and theories exist internationally that are not yet available in the United States, such as Bionic Vision Australia, Nano Retina in Israel, and several organizations in Japan . Germany’s Retina Implant AG has received European regulatory approval in July 2013 to offer its device called the Alpha IMS for treatment of retinitis pigmentosa. Its technology is significantly different from that of Second Sight. The Alpha IMS consists of a camera which facilitates finding an object through eye movements, similar to natural vision. However, since the camera is built into the eye, it is not possible to upgrade the system after initial surgery [10,11]. In contrast, Second Sight implants include an external camera: they are easier to upgrade but also require the user to move his/her entire head in a circle in order to properly perceive an object. The IMS technology is implanted in the eye and behind the ear, while Second Sight’s system is implanted around the eye .
Although both technologies help enhance and restore moderate vision, even seemingly minuscule differences are major improvements for the blind. The enhancement in quality of life will better the lives of millions of individuals by providing not only a new outlook on vision but also a novel perception of the world around them. In the words of patients, experiencing the implant is nothing short of “exciting” and “thrilling”. Retinal prosthesis is the beginning of a revolution that can end blindness as a disability, with the Alpha IMS and Second Sight devices pioneering the new spur of innovation. Though currently successful in restoring sight for patients suffering from retinitis pigmentosa, in the future, these bionic technologies may be able to help cure other forms of blindness and disease.
1. Hartford, Jamie. “Bionic Medical Devices: What’s Holding Them Back?” MDDI RSS. N.p., 31 July 2013. Web. 30 Mar. 2014.
2. “U-M Kellogg Eye Center performs first two retinal prosthesis implants in U.S. since FDA approval.” PR Newswire 29 Jan. 2014. Biography in Context. Web. 17 Feb. 2014.
3. Brady, Dennis, and Lena H. Sun. “FDA Approves Bionic Eye to Help the Blind.” Washington Post. 15 Feb. 2013: p. A.1. SIRS Issues Researcher. Web. 17 Feb. 2014.
4. White, Ronald D. “MADE IN CALIFORNIA; VISION OF THE FUTURE; Second Sight Medical in Sylmar has Won FDA Approval to Sell a Technology that Helps People Regain some Vision. Twenty Years and $200 Million are Invested in the Device.” Los Angeles TimesApr 28 2013. ProQuest. Web. 17 Feb. 2014
5. Hartford, Jamie. “Second Sight’s Argus II Bionic Eye Approved for Medicare Codes.” MDDI RSS. N.p., 15 August 2013. Web. 08 Mar. 2014.
6. Second Sight Foundation. “Medicare Designates Argus® II Retinal Prosthesis System as New Technology and Provides Payment.” Medicare Designates Argus II Retinal Prosthesis System as New Technology and Provides Payment. Second Sight, 15 Aug. 2013. Web. 30 Mar. 2014.
7. Brewer, Alyssa. “FYI: Can A Bionic Eye See As Well As A Human Eye?” Popular Science. N.p., 20 May 2013. Web. 18 Feb. 2014.
8. Wang, Shirley S., and Kristin Jones. “Corporate News: Bionic Eye Becomes a Reality —Retinal Device to Treat Blindness Gets U.S. Approval After Years in Development.” Wall Street Journal, Eastern edition ed.Feb 15 2013. ProQuest. Web. 17 Feb. 2014.
9. Rose, Steve, Dr. “The Argus II Is Approved. What’s Next for Bionic Retinas? – Eye on the Cure.” Eye on the Cure. N.p., n.d. Web. 09 Mar. 2014.
10. Stingl, Katrina, Dr. “Retina Implant AG Clinical Trial Results Presented at the 2013 American Academy of Ophthalmology Annual Meeting.” Retina Implant AG Clinical Trial Results Presented at the 2013… N.p., 18 Nov. 2013. Web. 10 Mar. 2014.
11. Editors. “Alpha IMS Vision Restoring Wireless Retinal Implant Now Cleared in Europe (VIDEO).” Alpha IMS Vision Restoring Wireless Retinal Implant Now Cleared in Europe (VIDEO). Medgadget, 8 July 2013. Web. 18 Feb. 2014.
12. Strickland, Eliza. “How Would You Like Your Bionic Vision?” – IEEE Spectrum. N.p., 13. Jan. 2012. Web. 18 Feb. 2014.
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