Novel photonic tools for cellular-scale interfacing with the retina

Optical retinal prostheses for blind patients with outer-retinal degenerative diseases could interface directly with surviving retinal neurons in order to create a meaningful percept in the brain. Recently, we introduced a technique based on the projection of light patterns with cellular dimensions onto genetically-modified retinas, for selectively controlling large neuronal populations in isolated mouse retinas.

Here, we describe novel optical systems which are capable of imaging cellular-scale retinal structures in small animal models in order to further test our light-based retinal prosthesis in vivo. First, we present a system for targeting multiple genetically-modified retinal ganglion cells (RGCs) in vivo with holographic patterns at a cellular resolution for vision restoration, while imaging the response in the visual cortex. Next, we use an intuitive optical model-based approach to build a simple, widely accessible system which yields sub-cellular resolution, two-photon images of fluorescent microstructures in the live retina, and demonstrate for the first time the ability to record activity from multiple retinal cells.

This suite of new tools enables long-term, repeated and artifact-free functional imaging of retinal and downstream neuronal activity in response to natural or artificial-light-based visual stimuli.