Soft 3D retinal implants with diamond electrode a way for focal stimulation

In neuroprostheses, the focal stimulation of the neuronal tissues is today a real challenge. These questions are particularly important in retinal prostheses to improve the quality of the images mapped onto an electrode array. It has been demonstrated that to achieve a normal vision the future generation of retinal implant must have 600 pixels with a pitch between electrodes around 50 μm. The long term in-vivo stability of electrodes in contact with the tissues remains a general and important challenge. After several days of implantation several histological studies show an inflammatory of the tissue at the interface between the electrode and tissues. Here we proposed a new approach based on retinal implants fabricated from 3D shaped diamond electrodes exhibiting both an improvement of the spatial resolution of the stimulation and a long term bio-inertness.