The core strategy of the Boston Retinal Implant Project (BRIP) is to create novel engineering solutions to treat blinding diseases that elude other forms of treatment. Our specific goal is to develop an implantable microelectronic prosthesis to restore vision to patients with certain forms of retinal blindness. The target diseases that we hope to treat include retinitis pigmentosa, which is the leading cause of inherited blindness in the world, and age-related macular degeneration, which is the leading cause of blindness in the industrialized world. Patients with these diseases become blind because of loss rods and cones, which are the only photoreceptive elements in the eye. Remarkably, despite this degeneration, a large number of the nerve cells that connect the eye to the brain remain relatively healthy. These surviving cells provide a special opportunity for visual rehabilitation with a prosthesis, which can deliver direct electrical stimulation to those cells that carry visual information to the brain.
Our research team was established in the late 1980s as a collaborative effort between the Massachusetts Eye and Ear Infirmary/ Harvard Medical School and the Massachusetts Institute of Technology. In 2001, the Department of Veterans Affairs (DVA) became an integral member of our research consortium. Additional information about the roles of the DVA in our program can be reviewed at: http://www.rehab.research.va.gov/cent/boston.htm.
The challenges of creating a prosthetic treatment for blindness demand innovations in both biology and engineering. Accordingly, we have assembled a multi-disciplinary research team includes: retinal surgeons, a neurologist, retinal physiologists, cortical physiologists, retinal anatomist, higher cortical "plasticity" researchers, computational neuroscientist, electrical engineers, microcircuit designers, microfabrication experts, software engineers, materials scientists, and a metallurgist. Our team has created an ultra-thin (i.e. several times thinner than a human hair), flexible, wireless micro-electronic device, which at its core contains a custom-designed, 30,000 transistor “stimulator” chip that will control delivery of electrical pulses to the retina. Our implant design has a number of special features, including ultra-low power design and a geometric design that minimizes that amount of hardware that is placed into the eye, and we have developed a minimally-invasive surgical method of implantation.
Our team has previously performed "acute" (i.e. hours-long) electrical stimulation studies in humans. We are now preparing a FDA application to seek permission to perform long-term implants into blind humans with an electronically-sophisticated retinal prosthesis that will use wireless communication technology and employ over 100 stimulating electrodes.