Peripheral Defocus, Pupil Size, and Axial Eye Growth in Children Wearing Soft Multifocal Contact Lenses in the BLINK Study.

Purpose: The purpose of this study was to evaluate the relationship between peripheral defocus and pupil size on axial growth in children randomly assigned to wear either single vision contact lenses, +1.50 diopter (D), or +2.50 D addition multifocal contact lenses (MFCLs). Methods: Children 7 to 11 years old with myopia (-0.75 to -5.00 D; spherical component) and ≤1.00 D astigmatism were enrolled. Autorefraction (horizontal meridian; right eye) was measured annually wearing contact lenses centrally and ±20 degrees, ±30 degrees, and ±40 degrees from the line of sight at near and distance. Photopic and mesopic pupil size were measured. The effects of peripheral defocus, treatment group, and pupil size on the 3-year change in axial length were modeled using multiple variables that evaluated defocus across the retina. Results: Although several peripheral defocus variables were associated with slower axial growth with MFCLs, they were either no longer significant or not meaningfully associated with eye growth after the treatment group was included in the model. The treatment group assignment better explained the slower eye growth with +2.50 MFCLs than peripheral defocus. Photopic and mesopic pupil size did not modify eye growth with the +2.50 MFCL (all P ≥ 0.37). Conclusions: The optical signal causing slower axial elongation with +2.50 MFCLs is better explained by the lens type worn than by peripheral defocus. The signal might be something other than peripheral defocus, or there is not a linear dose-response relationship within treatment groups. We found no evidence to support pupil size as a criterion when deciding which myopic children to treat with MFCLs.

Accommodation in Children after 4.7 Years of Multifocal Contact Lens Wear in the BLINK Study Randomized Clinical Trial.

SIGNIFICANCE: When worn for myopia control in children, soft multifocal contact lenses with a +2.50 D add reduced the accommodative response over a 3-year period, but wearing them for more than 4 years did not affect accommodative amplitudes, lag, or facility. PURPOSE: This study aimed to compare the accommodative response to a 3D stimulus between single-vision, +1.50-D add, and +2.50-D add multifocal contact lens wearers during 3 years of contact lens wear and then to compare accommodative amplitude, lag, and facility between the three groups after an average of 4.7 years of wear. METHODS: Bifocal Lenses In Nearsighted Kids study participants aged 7 to 11 years old were randomly assigned to wear single-vision, +1.50-D add, or +2.50-D add soft contact lenses (CooperVision, Pleasanton, CA). The accommodative response to a 3D stimulus was measured at baseline and annually for 3 years. After 4.7 years, we measured objective accommodative amplitudes, lead/lag, and binocular facility with ±2.00-D flippers. We compared the three accommodative measures using multivariate analysis of variance (MANOVA), adjusting for clinic site, sex, and age group (7 to 9 or 10 to 11 years). RESULTS: The +2.50-D add contact lens wearers exhibited lower accommodative response than the single-vision contact lens wearers for 3 years, but the +1.50-D add contact lens wearers exhibited only lower accommodative response than did the single-vision contact lens wearers for 2 years. After adjustment for clinic site, sex, and age group, there were no statistically significant or clinically meaningful differences between the three treatment groups for accommodative amplitude (MANOVA, P = .49), accommodative lag (MANOVA, P = .41), or accommodative facility (MANOVA, P = .87) after an average of 4.7 years of contact lens wear. CONCLUSIONS: Almost 5 years of multifocal contact lens wear did not affect the accommodative amplitude, lag, or facility of children.

Near visual function measured with a novel tablet application in patients with astigmatism.

CLINICAL RELEVANCE: While the clinical focus of performance metrics is traditionally based on visual acuity, research from the field of visual impairment has demonstrated that metrics such as reading speed and critical print size correlate much more strongly with subjective patient reported outcomes and assessed ability in real-world tasks. BACKGROUND: More recently, digital device use has increasingly replaced many paper-based tasks. Therefore, this study aimed to assess the correlation between standard acuity/contrast metrics and functional reading ability compared to real-world performance on an iPad-based reading task with astigmatic patients corrected wearing toric and mean spherical equivalent contact lenses. METHODS: Thirty-four adult participants, with -0.75 to -1.50-D of refractive astigmatism, were enrolled in a double-masked cross-over study and fitted with toric and spherical equivalent contact lenses, in random order. A digital application was developed to assess zoom, contrast modifications, the distance at which the tablet was held, blink rate, and time to complete the reading task. High and low contrast near logMAR visual acuity were measured along with reading performance (critical print size and optimal reading speed). RESULTS: The amount participants chose to increase tablet font size (zoom) was correlated with their high-contrast visual acuity with toric correction (r = 0.434, p = 0.010). With best sphere correction, zoom was associated with reading speed (r = -0.450, p = 0.008) and working distance (r = 0.522, p = 0.002). Text zoom was also associated with horizontal (toric: r = 0.898, p < 0.001; sphere: r = 0.880, p < 0.001) and vertical scrolling (toric: r = 0.857, p < 0.001; sphere: r = 0.846, p < 0.001). There was a significant negative association between the selection of text contrast and zoom (toric: r = -0.417, p = 0.0141; sphere: r = -0.385, p = 0.025). CONCLUSION: Real-world task performance allows more robust assessment of visual function than standard visual metrics alone. Digital technology offers the opportunity to better understand the impact of different vision correction options on real-world task performance.

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

SIGNIFICANCE: 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. PURPOSE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: This study used digital devices to demonstrate realistic benefits of toric contact lens designs for astigmatic patients.

A Randomized Trial of Soft Multifocal Contact Lenses for Myopia Control: Baseline Data and Methods.

SIGNIFICANCE: The Bifocal Lenses In Nearsighted Kids (BLINK) study is the first soft multifocal contact lens myopia control study to compare add powers and measure peripheral refractive error in the vertical meridian, so it will provide important information about the potential mechanism of myopia control. PURPOSE: The BLINK study is a National Eye Institute-sponsored, double-masked, randomized clinical trial to investigate the effects of soft multifocal contact lenses on myopia progression. This article describes the subjects' baseline characteristics and study methods. METHODS: Subjects were 7 to 11 years old, had -0.75 to -5.00 spherical component and less than 1.00 diopter (D) astigmatism, and had 20/25 or better logMAR distance visual acuity with manifest refraction in each eye and with +2.50-D add soft bifocal contact lenses on both eyes. Children were randomly assigned to wear Biofinity single-vision, Biofinity Multifocal "D" with a +1.50-D add power, or Biofinity Multifocal "D" with a +2.50-D add power contact lenses. RESULTS: We examined 443 subjects at the baseline visits, and 294 (66.4%) subjects were enrolled. Of the enrolled subjects, 177 (60.2%) were female, and 200 (68%) were white. The mean (± SD) age was 10.3 ± 1.2 years, and 117 (39.8%) of the eligible subjects were younger than 10 years. The mean spherical equivalent refractive error, measured by cycloplegic autorefraction was -2.39 ± 1.00 D. The best-corrected binocular logMAR visual acuity with glasses was +0.01 ± 0.06 (20/21) at distance and -0.03 ± 0.08 (20/18) at near. CONCLUSIONS: The BLINK study subjects are similar to patients who would routinely be eligible for myopia control in practice, so the results will provide clinical information about soft bifocal contact lens myopia control as well as information about the mechanism of the treatment effect, if one occurs.