Abstract
Purpose :
The goal of this study is to examine anatomical and visual function outcomes in patients with implantation of the Argus II Retinal Prosthesis. The primary objective is to determine whether the average gap distance between the electrode array and retina correlates with changes in objective visual function and sensitivity detection thresholds.
Methods :
5 patients with implantation of the Argus II Retinal Prosthesis were enrolled in this single-institution retrospective study. Surgeries were conducted by a single retinal surgeon at Stony Brook University Hospital. Visual function data (Square Localization [SL] and Direction of Motion [DOM]) and OCT images (Cirrus-SD-OCT) were extracted from the Argus II Retinal Prosthesis Post-Approval study. Data was obtained at baseline, and post-operative month 1, month 3, month 6, and year 1. Electrode array-retina gap distances were measured at each of the 60 electrodes on the array using the Cirrus SD-OCT caliper measurement tool. Visual function tests were performed with the device OFF and ON at each study visit. Sensitivity detection thresholds were obtained at the initial programming visit and each reprogramming session.
Results :
2 out of 5 patients had a statistically significant average improvement in the SL visual function test when the device was ON compared to OFF (p < 0.05). Electrode array-retina gap distance did not show a significant correlation with changes in SL visual function when the device was ON compared to OFF (r = 0.20; p = 0.74). None of the patients had a significant average improvement in the DOM visual function test when the device was ON compared to OFF (p > 0.05). Electrode array-retina gap distance did not show a significant correlation with changes in DOM visual function when the device was ON compared to OFF (r = -0.18; p= 0.77). In addition, electrode array-retina gap distance did not show a significant correlation with sensitivity detection threshold (r = -0.01; p = 0.98).
Conclusions :
Our results demonstrate that the average electrode array-retina gap distance does not correlate with changes in objective visual acuity function or sensitivity detection threshold in patients with the Argus II Retinal Prosthesis. Therefore, complete apposition between the electrode array and retina may not be necessary to achieve optimal visual outcomes.
This is a 2020 ARVO Annual Meeting abstract.