Abstract
Purpose :
In a previous study, a reading test based on vanishing optotype characters (Ora Vanishing Optotypes Reading Test™) was used to assess visual function impairment in early AMD patients compared to age-matched controls. The current study aims to investigate the usefulness of this test after one-year follow-up testing of the previously investigated early AMD cohort.
Methods :
In the initial study, subjects with non-advanced AMD: N = 11 (grade 1 to 4 on AREDS simplified scale) and normal controls N = 24 (AREDS grade 0) with best visual acuity (VA) 20/25 or better (in both groups) were included. In the one-year follow-up, 9 non-advanced AMD subjects and 16 control subjects were again tested. All testing procedures used in the initial study were repeated in the follow-up. The reading test was administered monocularly with best correction in place. All subjects were asked to read nine passages of pepper words at successively lower contrast levels with a maximum contrast passage as baseline. Reading speed in words per minute (wpm) was recorded for each passage. The primary outcome was reduction of reading speed relative to baseline. Only subjects that participated in both trials were included in the comparison.
Results :
At the initial visit, there was no difference in reading speed between groups at maximum contrast [102.0 ± 16.7 wpm (AMD) and 96.2 ± 18.9 wpm (control) (p = 0.2)]. These findings were replicated at 1-year follow-up: [97.6 ± 15.2 wpm (AMD) and 95.9 ± 17.2 wpm (control) (p = 0.8)]. Although reading speed relative to subject baseline tested lower for the AMD group at reduced contrast levels during the initial visit, this did not achieve significance. However, after one year, reading performance was found to be significantly impaired in AMD subjects compared to controls at 7 out of the 9 tested contrast levels (p < 0.02).
Conclusions :
Results of the one-year follow-up showed good reproducibility and a potential utility of this technique as a novel functional endpoint in non-advanced AMD clinical trials.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.