An implant to delay blindness
Retinitis pigmentosa is a degenerative eye disease that affects approximately one in 3,000 people. It is a genetic disorder that causes the light-sensing cells of the retina to gradually die. The first indication of visual impairment usually occurs somewhere between 10 and 30 years of age. The loss of vision is progressive, moving from the edges of vision into the centre, until no useful vision remains.
There is currently no way to protect against the loss of retinal cells in degenerative conditions, such as retinitis pigmentosa and age-related macular degeneration, which are the leading cause of blindness in working age adults in developed nations. A transformative therapy would be to halt retinal degeneration in the early stages of the disease before patients lose useful vision – prevention is better than cure!
The Bionics Institute has pioneered a small device that is positioned between the two back layers of the retina and provides therapeutic electrical stimulation to protect the retina from further degeneration. The idea for this device emerged from our work as part of Bionic Vision Australia – a national consortium of research organisations that developed and clinically trialled a prototype bionic eye in three patients with advanced retinitis pigmentosa (2010 – 2015). Rather than using a retinal implant and electrical stimulation to evoke visual perceptions in blind patients, our researchers realised that a simpler and smaller device could provide low levels of electrical stimulation to halt retinal degeneration.
Together with clinical colleagues at the Centre for Eye Research Australia and the Royal Victorian Eye and Ear Hospital, we have designed an implant capable of extending the years of useful vision for retinitis pigmentosa patients. Due to its location between the two back layers of the eye, this implant will not interfere with, or risk, natural vision. This is important because the therapy will be initiated at an early stage of disease progression when patients still have normal central vision.
In 2017 we commenced the translational studies to develop and safety-test a human-grade implant in preparation for a future clinical trial. Our goal is to reduce the societal and personal impact of progressive vision loss, and improve the quality of life of the many people who live with degenerative retinal diseases.
Program leader: A/Prof Chris Williams