Spatially Localized Visual Perception Estimation by Means of Prosthetic Vision Simulation

Area of Science:

• Biomedical Engineering
• Neuroscience
• Ophthalmology

Background:

• Retinal prosthetics aim to restore vision via electrical stimulation.
• Understanding phosphene properties is crucial for device improvement.
• Current 2D arrays offer limited, dot-like visual perceptions.

Purpose of the Study:

• To analyze the impact of 2D and 3D electrode array designs on retinal stimulation.
• To compare the cell selectivity and stimulation characteristics of different array topologies.
• To establish a method for evaluating 3D electrode arrays for high-density, selective retinal cell activation.

Main Methods:

• Developed a 3D computational model in COMSOL Multiphysics simulating retinal electrical stimulation.
• Included retinal interface elements and voltage-gated ionic channel dynamics.
• Verified cell stimulation and compared simulation findings with clinical data from 2D arrays.

Main Results:

• Simulation results align with clinical observations for 2D arrays, enabling analytical models.
• Identified distinct visual sensations evoked by 2D and 3D arrays.
• The 3D array demonstrated potential for lower-threshold activation and improved cell selectivity compared to the 2D array.

Conclusions:

• The 3D linear electrode array design shows promise for enhancing cell selectivity in retinal prostheses.
• This design may allow for the activation of individual retinal ganglion cells (RGCs) at higher densities.
• The study provides a proof-of-concept for utilizing 3D arrays for safe and selective RGC activation.