Randomized Clinical Trial of Near Visual Performance with Digital Devices Using Spherical and Toric Contact Lenses.

Abstract

Visual demands today incorporate a significant amount of time using digital devices. Results of this randomized crossover study of spherical and toric contact lenses demonstrated that participants were able to read smaller print size more comfortably and preferred toric contact lenses when using digital devices. The purpose of this study was to assess how toric contact lens correction affects subjective and objective outcomes of astigmatic patients using real-world digital devices. Adult participants, aged between 20 and 38 years with -0.75 to -1.50 D of astigmatism were enrolled in this double-masked randomized crossover 10-day study of Alcon Dailies Aqua Comfort Plus Sphere and Toric (Alcon, Geneva, Switzerland) contact lenses. Electronic high- and low-contrast near logMAR visual acuity and contrast sensitivity were tested. Reading performance was assessed using custom iPad applications; one used a reading sentences test, whereas the other analyzed zoom, contrast, and distance with website-based articles. Participants completed the Near Activity Visual Questionnaire and stated their preferred contact lens correction. Thirty seven participants were screened, 35 participants were enrolled, and 34 participants completed the study. Toric lens correction improved near high- and low-contrast visual acuity by 0.5 to 1 full line (P < .0001) and allowed participants to read one line smaller text on the iPad (P = .01). Participants increased the zoom 11% (P = .004) and the contrast 4% (P = .006) more with spherical lenses while reading articles. Participants held the iPad at approximately the same distance, about 33 cm (P = .63). Eighty five percent of participants preferred the toric correction (P < .0001). Participants reported improved satisfaction with toric lens correction (P = .0002) and noticed the most benefit with tasks such as reading small print and labels/instructions. This study used digital devices to demonstrate realistic benefits of toric contact lens designs for astigmatic patients.