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Updated: Apr 28, 2026
Author Spotlight: Enhancing Grasping Abilities for Hemiplegic Patients with Flexible Robotic Limbs
Published on: October 27, 2023
The Argus II prosthesis facilitates reaching and grasping tasks: a case series
Aachal Kotecha1, Joe Zhong, David Stewart
1NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK. aachal.kotecha@ucl.ac.uk.
Background:
To evaluate the reach-to-grasp performance of patients fitted with an epiretinal artifical retina device.
Methods:
This was a hospital-based case series consisting of six patients fitted with the Argus II (Second Sight Medical Products Inc, California, USA) retinal prosthesis. Participants were asked to reach out and pick up a high-contrast cuboid object with the prosthesis in the 'On', 'Off' or 'Scrambled' setting presented in a randomised order. The 'Scrambled' setting consisted of a random, scattered signal presented to the prosthesis. The session was repeated after a 4-6 week period. Hand movements were measured using motion detection cameras. The number of successful object grasps was calculated.
Results:
The number of successful grasps was greater with the prosthesis in the 'On' setting (visit 1: median [interquartile range] percentage success: 'Off' = 0 [0 to 50]%, 'On' = 69 [67 to 95]%, 'Scrambled' = 59 [42 to 95]%; Friedman Chi-squared test statistic 6.5, p = 0.04; visit 2 median [IQR] percentage success: 'Off' = 0 [0 to 25]%, 'On' = 69 [53 to 100]%, 'Scrambled' = 28 [13 to 63]%; Friedman Chi-squared test statistic 8.4, p= 0.02).
Conclusions:
The use of an electronic retinal prosthesis facilitates reach-and-grasp performance. Further work should explore how performance can be improved with targeted rehabilitation.
