Abstract
Purpose :
Accommodation of the eye in response to multifocality of a lens may impact the myopia control efficacy of the lens. A soft contact lens (SCL) with the RingBoostTM technology (RB) was designed to maximize myopia control effect without affecting normal accommodation of the eye. The study evaluated accommodative response (AR) of the RB lens by comparing with other SCL and spherical spectacle (SL) corrections.
Methods :
The study was double-masked with a cross-over design. AR of 10 adults (18-24 yrs) was assessed with bilateral wear of SL at baseline and four SCLs of different designs in random order: single-vision (SV), dual-focus (DF), center-distance multifocal (MF), and RB. Refractive states (RS) of the subject’s right eye under four levels of target vergences (TV) between 0.25 and 4.59 D were determined based on spherical equivalent power measured by an open-field auto-refractor (GS) and Shack-Hartmann wavefront aberrometry (under natural pupils) with three analytical methods: minimum wavefront RMS (minRMS), best-sphere fit to the wavefront (MTR), and paraxial focus (PF). Slopes of accommodative responses (SAR) were obtained from linear fit of RS to TV and compared among lens types.
Results :
AR of RB, DF, MF, SV, and SL by four refractive methods are provided in Figure 1. Results varied by method of RS determination and lens type. SARs (D/D) of RB were not significantly different from SV with all four refractive metrics (p>0.05) and was statistically larger than SL with minRMS by 0.13 (95%CI: 0.05, 0.21). SARs of DF were statistically smaller than SV with MTR and minRMS but larger than SV and SL with GS (p<0.05). SARs of MF were statistically smaller than SV and SL with all four metrics (p<0.05) except for PF when compared to SV (p>0.05). Compared to DF, SARs of RB were statistically larger by 0.13 (0.05, 0.22) and 0.11 (0.03, 0.19) with minRMS and MTR, respectively, but smaller with GS by 0.09 (0.03, 0.15).
Conclusions :
This exploratory study demonstrated interpretation of accommodative response differed by method of RS determination. However, across all metrics, RB lens had similar or better AR than single-vision corrections. AR measured with the open-field auto-refractor provided largely consistent results with those of wavefront-based methods except with DF. Optimal method to quantify RS in myopia control lenses requires further investigation.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.