A consortium of researchers in Australia has completed the first clinical trial of bionic eye technology that restores sight to people with profound vision loss.
Bionic Vision Australia (BVA) began a two-year study in May 2012 of its prototype 24-channel percutaneous implant in three patients with profound vision loss from the eye disease retinitis pigmentosa (RP). RP is an inherited, degenerative eye disease that causes severe vision impairment and often blindness through progressive degeneration of the retina and death of the photoreceptors.
BVA’s systems convert video images captured by a miniature camera housed in a patient's glasses into a series of electrical pulses. This signal is transmitted wirelessly to an array of electrodes that are implanted on the surface of the patient’s retina. These pulses are intended to stimulate the retina's remaining cells, resulting in a corresponding perception of patterns of light in the brain.
Following the implant surgery patients learn to interpret these visual patterns thereby regaining some functional vision, allowing them to detect shapes of people and objects in their surroundings.
The three patients each received surgically-implanted suprachoroidal electrode implants to aid the restoration of vision. Although this was designed to be primarily a proof-of-concept and safety study, the trial also generated efficacy data showing that the device improved patient’s ability to see light and shapes, and helped with navigation around obstacles and detection of items on a tabletop search task.
‘This study is critically important to the continuation of our research efforts and the results exceeded all our expectations,’ Professor Mark Hargreaves, chair of the BVA board, commented. ‘We have demonstrated clearly that our suprachoroidal implants are safe to insert surgically and cause no adverse events once in place. Significantly, we have also been able to observe that our device prototype was able to evoke meaningful visual perception in patients with profound visual loss.’
With this study complete, BVA has three other programs underway. The first of these, a 44-channel device will enter the clinic in mid-2015. The consortium is also developing a 98-channel device and a high acuity device.
BVA will be available to discuss this study at the AdvaMed2014 conference in Chicago on 6-8 October.
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