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Factors affecting two-point discrimination in Argus II patients
Ezgi I Yücel1, Roksana Sadeghi2, Arathy Kartha3
1Department of Psychology, University of Washington, Seattle, WA, United States.
Frontiers in Neuroscience
|September 12, 2022
Summary
High current stimulation and poor vision in epiretinal implants result from axonal stimulation, device lift, and retinal damage. Understanding these factors is key to improving visual prosthetics for the blind.
Area of Science:
- Biomedical Engineering
- Neuroscience
- Ophthalmology
Background:
- Epiretinal prosthesis technology faces challenges with high current thresholds and limited pattern vision.
- The Argus II implant aims to restore vision but has performance limitations.
Purpose of the Study:
- To investigate the causes of high current amplitude thresholds and poor spatial resolution in the Argus II epiretinal implant.
- To identify factors limiting the performance of visual prosthetics.
Main Methods:
- Measured current amplitude thresholds in three blind participants with Argus II devices.
- Assessed two-point discrimination to evaluate spatial resolution.
- Utilized data and simulations to analyze performance-limiting factors.
Main Results:
- Axonal stimulation, device lift, and retinal damage were identified as contributors to reduced performance.
- These factors were shown to limit sensitivity and/or spatial resolution.
- Performance limitations were observed in the Argus II epiretinal implant.
Conclusions:
- Understanding the roles of axonal stimulation, lift, and retinal damage is crucial for improving epiretinal implant performance.
- These findings are critical for the development and surgical implantation of devices that restore pattern vision.
- Further research is needed to overcome current limitations in visual prosthetic technology.
