Computational Modeling of Electromagnetic and Thermal Effects for a Dual-Unit Retinal Prosthesis: Inductive Telemetry, Temperature Increase, and Current Densities in the Retina - Artificial Sight: Basic Research, Biomedical Engineering, and Clinical Advances - page 302

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Figure 15.17. Impedance method simulation results: (a) logarithmic colorplot represents
current densities in slice of 3D retinal model (lighter = more current). (b) Line plot
showing current densities for a cross section through the ganglion cell layer. The effect
of the current injected by each individual electrode can be seen as a peak in the current
density value, aligned with the spatial position of each electrode.
Knowing the current densities in the retinal tissue could help understanding how
effectively the implant will operate. It also helps answering a number of questions
regarding thedesignof implantableelectrodearrays, includingdeterminingaproper
location for the implant to be placed, measuring efficiency of different shapes
and sizes of electrodes to be used, calculating the optimal inter-electrode spacing,
finding a convenient location for the current return, and verifying that the implant
will provide safe levels of current to the surrounding tissue.