Two blind British men have regained partial sight after light receptors developed by Oxford researchers were implanted into their retinas.
Chris James and Robin Millar were fitted with eletronic retinas during a trial coordinated by Oxford University. Both men have retinitis pigmentosa, a rare hereditary condition which causes the light sensing cells in the retina to degrade over time eventually leading to blindness. 3,000 to 4,000 people in Europe suffer from the disease.
The retinal implants were developed in Germany. The method consists of 1,500 light sensing diodes sending impulses through the healthy optic nerve. This is a low resolution compared to a natural retina, which has tens of millions of light sensitive ‘rod’ and ‘cone’ cells. Previous implants produced by US ‘Second Sight’ depended upon an external camera attached to sunglasses.
The sight differs to normal sight, consisting of horizontal and vertical flashes of light. It takes several days for the brain to meaningfully interpret the information being received.
The 3 millimetre microchips were researched by Merton Fellow and Professor of Ophthalmology, Robert MacLaren. James Ramsden of University Hospitals and Markus Groppe, an academic clinical lecturer, performed the operation.
Chris James, who received his implant in Oxford, could identify the curve of a plate after 10 years of blindness. The other recipient, Robin Millar, called the implant “an extraordinary thing” and has begun dreaming in colour for the first time in 15 years. The results have exceeded the expectations of Professor MacLaren, who had hoped that under best conditions patients might see the top letter of an eye chart.
If trial success continues the retinal implant may join the cochlear implant, which has helped over 150,000 people worldwide regain some hearing. ‘The blind shall see and the deaf shall hear’ used to be gospel miracles, now for some it will be a bionic success.
The two men are first among 12 trial operations, some of which will take place at the Oxford Eye Hospital.
