NEW YORK (October 21, 2009) -- A 50-year-old New York woman who was diagnosed with a progressive blinding disease at age 13 was implanted with an experimental electronic eye implant that has partially restored her vision. A team led by Dr. Lucian V. Del Priore at NewYork-Presbyterian Hospital/Columbia University Medical Center performed the June 26 surgery -- the first case of its kind in New York.
The first treatment aimed at restoring limited sight in people blinded by retinal disease, it is currently available as part of a multicenter clinical trial.
The implant -- a component of the Argus™ II Retinal Stimulation System by Second Sight® Medical Products Inc., of Sylmar, Calif. -- is designed to stimulate retinal cells directly. In a healthy eye, photoreceptor cells of the retina receive light and translate it into signals that are sent to the brain via the optic nerve. But in patients with a genetic, blinding disease called retinitis pigmentosa (RP), these light-processing cells gradually degenerate, leading to severe vision loss or total blindness.
"With this system, people who are functionally blind might begin to distinguish light from dark, recognize visual patterns, make out figures, see food on a plate and navigate in unfamiliar surroundings," says Dr. Del Priore, site principal investigator, professor in the Department of Ophthalmology at Columbia University College of Physicians and Surgeons, and an ophthalmologist at NewYork-Presbyterian Hospital/Columbia University Medical Center. "In its current form, the device won't restore full visual function -- but if it dramatically reduces a patient's disability, that is a major advance."
Retinitis pigmentosa only affects the outer layer of retinal cells, leaving the inner layers healthy and capable of conducting electricity, Dr. Del Priore explains. Therefore, people with glaucoma, diabetic retinopathy, optic nerve disease, or a history of retinal detachment have been excluded from the study, as their level of retinal impairment is likely to be more severe and more generalized. At this point, the device is being tested exclusively in people with RP as part of a clinical trial offered at six sites across the country.
From Video Images to Sight
Argus II and its predecessor, Argus I, have already been implanted to reduce some aspects of vision loss in about 20 patients with RP in the United States. Dr. Del Priore and his surgical team are optimistic about the newest patient's prospects, based on positive results in others who have participated in studies of the system thus far. The device was developed by Second Sight under the lead of Dr. Mark Humayun, who is currently at the University of Southern California. NewYork-Presbyterian/Columbia's study coordinator, Elona Gavazi, was instrumental in screening and recruiting patients for the current study.
Argus II comprises three components: the implanted part, which is placed inside the patient's eye; a tiny camera and transmitter, mounted on a pair of sunglasses; and a wireless microprocessor and battery pack, to be worn on a belt. The implant itself contains 60 tiny electrodes that are attached to the retina via a micro-wire roughly the width of a human hair. These administer electrical impulses to retinal cells, allowing the brain to perceive light.
Learning to See Again
Argus II is an innovative technology, Dr. Del Priore continues, but it is the rehabilitation process that will ensure a patient's ability to benefit from the procedure. In fact, without visual training, the patient may not learn to use or accept the images being received.
The intensive phase of rehab takes about six months, he says, but the process can continue for a year or more. Rehabilitation, device training, along with functional assessment of the patient's vision, will take place at Lighthouse International, a leading international non-profit vision rehabilitation and research organization, which is a collaborating institution with NewYork-Presbyterian/Columbia in the clinical trial.
At the Arlene R. Gordon Research Institute of Lighthouse International, senior fellow in vision science Aries Arditi, Ph.D., principal investigator of the Lighthouse site, will conduct psychophysical testing of the patient with and without the device to assess her performance of specific visual tasks, such as pattern recognition, aiming the device's camera with head movements, and using the system for orientation and navigation. Dr. Arditi will also help determine which training procedures will allow the patient to make the most of her newly restored, if limited, vision -- insights that can be carried forward for the benefit of future device recipients.
"We are very pleased to be a part of this groundbreaking and exciting research and to be working with such outstanding partners. Our collective work could have a profound effect on the estimated 400,000 Americans with retinitis pigmentosa and other retinal diseases," states Dr. Arditi.
For more information, patients may call (866) NYP-NEWS.
Columbia University Medical Center
Columbia University Medical Center provides international leadership in basic, pre-clinical and clinical research, in medical and health sciences education, and in patient care. The Medical Center trains future leaders and includes the dedicated work of many physicians, scientists, public health professionals, dentists, and nurses at the College of Physicians & Surgeons, the Mailman School of Public Health, the College of Dental Medicine, the School of Nursing, the biomedical departments of the Graduate School of Arts and Sciences, and allied research centers and institutions. Established in 1767, Columbia's College of Physicians and Surgeons was the first institution in the country to grant the M.D. degree and is now among the most selective medical schools in the country. Columbia University Medical Center is home to the largest medical research enterprise in New York City and state and one of the largest in the United States. For more information, please visit www.cumc.columbia.edu.
NewYork-Presbyterian Hospital, based in New York City, is the nation's largest not-for-profit, non-sectarian hospital, with 2,242 beds. The Hospital has nearly 2 million inpatient and outpatient visits in a year, including more than 230,000 visits to its emergency departments -- more than any other area hospital. NewYork-Presbyterian provides state-of-the-art inpatient, ambulatory and preventive care in all areas of medicine at five major centers: NewYork-Presbyterian Hospital/Weill Cornell Medical Center, NewYork-Presbyterian Hospital/Columbia University Medical Center, NewYork-Presbyterian Morgan Stanley Children's Hospital, NewYork-Presbyterian Hospital/The Allen Hospital and NewYork-Presbyterian Hospital/Westchester Division. One of the largest and most comprehensive health care institutions in the world, the Hospital is committed to excellence in patient care, research, education and community service. NewYork-Presbyterian is the #1 hospital in the New York metropolitan area and is consistently ranked among the best academic medical institutions in the nation, according to U.S.News & World Report. The Hospital has academic affiliations with two of the nation's leading medical colleges: Weill Cornell Medical College and Columbia University College of Physicians and Surgeons. For more information, visit www.nyp.org.
The Arlene R. Gordon Research Institute at Lighthouse International is dedicated to expanding knowledge about visual function and the psychosocial aspects of vision impairment. Research conducted provides an empirical foundation for the development of Lighthouse vision rehabilitation services and professional training programs. Consisting of a multidisciplinary team, the Research Institute is the only one of its kind housed within a vision rehabilitation agency. Founded in 1905, Lighthouse International is a leading non-profit organization dedicated to fighting vision loss through prevention, treatment and empowerment. It achieves this through clinical and rehabilitation services, education, research and advocacy. For more information about vision loss and its causes, contact Lighthouse International at (800) 829-0500 or visit www.lighthouse.org.