Wireless Organic Neuroprostheses

Implantable neural prostheses are devices exploited to recover impaired or lost functions. A common design constraint is the presence of cables connecting the electrode-tissue interface to implantable electronic units. The presence of wires and connectors is a significant disadvantage for neural prostheses. They are weak points often leading to failure, they exert mechanical forces and tractions on the implant and the tissue, and they might lead to post-surgical complications, such as infection. Also, the use of implantable electronic units is another disadvantage due to constraints in power consumption, heat generation, and high risk of failure in a wet environment due to leakage. In neurotechnology, truly wireless electrodes are highly desirable. Retinal prostheses are an example of neural prostheses, in which wireless neuronal stimulation is achieved using photovoltaic technology, that avoids the need for active implantable electronic units, cables and connectors. In the case of retinal stimulation, photovoltaic technology is intuitive since the eye has a transparent window allowing the retina to absorb light entering from the pupil. This solution allows retinal prostheses to avoid a transscleral flat cable which limits the maximum number of stimulating pixels on the device and induce post-operative complications such as eye inflammation or leakage through the incision. In the first part of this talk, the validation in-vivo of a wide-field, photovoltaic, and injectable retinal prosthesis will be reported. In the second part of the talk, I will shortly present the extension of organic neuroprosthesis from blindness to other applications.