Binocular and Accommodative Function of S.T.O.P® contact lenses compared to MiSight

Abstract

Purpose : To compare the binocular and accommodative function of Spatio-Temporal Optical Phase (S.T.O.P®) contact lenses (CL) against MiSight® (MS) in myopic young adults. S.T.O.P CL feature rotationally asymmetric power maps, designed with meridionally and azimuthally varying power distributions, combined with a peripheral carrier configured with rotation assisting features The resulting dynamic optical signal on the retina may decelerate the rate of myopia progression and minimise the decay of treatment effect found in options which provide a relatively static optical signal.

Methods : Prospective, randomized, single-masked (participant), cross-over trial where participants aged 18-39 years wore MS and two S.T.O.P designs (F2 and DT), each for a minimum of 5 days at 6 hours/day, daily wear, with CLEARCARE disinfection. Assessments occurred while wearing each design at the end of the wearing cycle. Binocular function assessments comprised phoria at 3m and 40cm (Modified Thorington). Accommodative function measurements comprised monocular accommodative facility (MAF) at 40cm (±2.00D, left eye occluded), and dynamic accommodative response (AR) at 6m, 70cm, and 40cm. Dynamic AR was calculated from autorefraction measurements (Grand Seiko WAM5500, high speed mode: 6 measurements/s) on the left eye (not wearing a CL and occluded under black cardboard placed on the tilted hot mirror), while the right eye (wearing a CL) viewed each target. Customized hardware was used to coordinate measurements, which were recorded for 8s at each distance (144 measurements in total).
Differences between designs were assessed using linear mixed model, a Bonferroni correction was applied where applicable, and significance was set at 5%.

Results : While wearing F2 compared to MS, MAF was higher (12.2±5.9 vs. 10.5±5.3, p=0.007) and AR was lower at 70cm (0.75±0.36 vs 0.95±0.37, p<0.001) and 40cm (1.58±0.55 vs 1.74±0.50, p=0.007). The SD of AR measurements was also lower with F2 compared to MS at 70cm and 40cm (p<0.001), suggesting accommodation was more consistent with F2. There were no differences between designs for phoria at either 3m or 40cm (p>0.2), nor were there any differences between DT and MS for any measurement (p>0.06).

Conclusions : Both S.T.O.P designs were comparable to MS for binocular function. DT was comparable to MS for accommodative function. F2 was better for MAF and required less accommodation compared to MS.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.