Abstract
Purpose :
To compare the visual performance of optical films with Spatio-Temporal Optical Phase (S.T.O.P.®) technology against a control.
S.T.O.P. films feature optical elements with azimuthally varying power distributions that are arranged rotationally asymmetric in a peripheral treatment zone. When adhered to single vision spectacle lenses (SVSL) and swapping designs frequently, S.T.O.P. films provide a dynamic signal that is hypothesized to reduce and sustain myopia progression.
Methods :
Randomized, single-masked, bilateral wear, clinical trial where 42 participants aged 18-40 years wore a control-film pair (CFP, no optical elements) and four S.T.O.P. test-film pairs (TFP) (designs: E, F-1, F-2, and G) applied to SVSL, each for at least 3 days. Visual performance was assessed with subjective ratings (1-10 scale) for clarity of vision (far, intermediate, near), overall vision satisfaction, vision at night and whilst walking. Willingness to purchase was assessed via Yes/No response. Acuity-based measures comprised monocular high and low contrast visual acuity (HCVA/LCVA), contrast sensitivity (CS) at 6m and binocular HCVA at 6m and 40cm. Phorias were measured at 3m and 40cm. HCVA, LCVA, CS and phorias were compared between CFP/no film and between CFP/each TFP. Differences between designs were assessed using linear mixed model, a Bonferroni correction was applied where applicable, and significance was set at 5%.
Results :
CFP performed better than any TFP for clarity of vision at all distances (9.1±1.4 vs 6.3-6.9±2.1-2.3, p<0.001), overall vision satisfaction (9.1±0.9 vs 6.0-6.9±2.0-2.2, p<0.001), vision at night (9.0±1.2 vs 6.6-7.4±1.4-2.1, p<0.001), vision when walking (9.1±1.2 vs 6.6-7.1±1.9-2.2, p<0.001) and willingness to purchase (Yes: 95% vs 37-58%, p<0.001). The average visual performance scores for the CFP, E, F-1, F-2 and G designs were 9.1, 6.7, 6.7, 6.4 and 6.9, respectively. CFP was worn longer each day than any of the TFP (8.1±2.7 vs 6.3-7.0±2.1-2.7 h, p<0.001).
There was no difference in any HCVA, LCVA, CS or phoria measure between CFP/no film (p>0.08). Binocular HCVA at 40cm was better with CFP compared to both F-1 and F-2 (mean △<2 letters, p≤0.048).
Conclusions :
Visual performance ratings with the four S.T.O.P. film pairs were 18-34% lower than with CFP. Despite the lower ratings, visual acuity-based measures with CFP and TFP were unaffected or clinically insignificant when compared to no film on SVSL and CFP, respectively.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.