Introduction: The Monash University Bionic Vision Program commenced in April 2010 and aims to develop and implant a human bionic vision device by end 2013. There are theoretical reasons why cortical stimulation could produce better resolution of vision compared with retinal stimulation. Human visual cortex stimulation produces light percepts (phosphenes) and we believe that with a high enough density of electrodes spread over the primary occipital cortex (VI) that there would be sufficient resolution of vision via a digital camera/computer interface, that completely blind subjects would be able to navigate the environment and read large print.
Methods: This is a collaborative project between the Departments of Electrical and Computer Systems Engineering, Physiology, Surgery and Ophthalmology at Monash University and the Alfred Hospital. Commercial partners are miniFAB™ and Grey Innovation. A multi-tiled wireless electrode array has been developed. Each tile has 45 insulated titanium micro-electrodes which will penetrate the calcarine (VI) cortex. There will be > 650 electrodes implanted unilaterally. An insertion tool has been developed for accurate atraumatic implantation of the electrode grids. A small unilateral occipital craniotomy will be performed for access. Robotic vision algorithms have been incorporated into the ‘pocket’ computer which will enhance the visual percepts. The selection and preparation of candidates, and the development of a psychophysics testing program are crucial for verification of functional improvement and to the success of the program.
Results: The progress to date in computer vision algorithms, system component design and experimental results in rats, sheep and non-human primates will be presented. The challenges of producing a safe effective commercial device which is approved by the regulators will be discussed.
Conclusions: The development of a cortical implant for bionic vision is achievable. This University/private industry commercial partnership is a strong model for translational research in neurosurgery.
Patient Care: Our aim is for severely sight impaired individuals implanted with the cortical bionic vision device to improve their general functional capacity in terms of navigation, identification of objects by sight and possibly reading large print.
Learning Objectives: 1. Appreciate the historical development of bionic vision devices.
2. Understand the relative advantages and disadvantages of retinal versus cortical bionic vision devices.
3. Appreciate the technical challenges in developing a wireless bionic vision device
4. Appreciate the preclinical studies required before human implantation.
5. Appreciate the challenges in selection of candidates and the biophysics and rehabilitation requirements for the recipients in a clinical trial