Closed-loop Optimization of Retinal Ganglion Cell Responses to Epiretinal Stimulation: A Computational Study

Retinal prostheses improve vision for patients with retinal degeneration. However, the shape recognition ability of retinal prostheses users is limited due to the low visual resolution of these devices. Off-target retinal ganglion cell (RGC) activation is an important contributing factor to the low stimulation precision. Previous research has shown RGC spatial activity and perception of shapes by users can be difficult to predict due to the complexity of retina structure and electrode-retina interactions. In this study we demonstrate a method to iteratively search for optimal stimulation parameters that create focal RGC activation in silico. Our findings indicate that stimulation parameters can be customized to each electrode in a closed-loop manner. This approach can potentially eliminate the time-consuming process of searching a broad range of parameters for optimal stimulation outcome and provide more control over personalized fitting of retinal implants.