Lens fitting and subjective acceptance of senofilcon A with photochromic additive on a neophyte population.

PURPOSE: To determine the proportion of contact lens neophytes that can be successfully fitted with a photochromic contact lens, and to survey subjective performance outcomes compared to habitual spectacles. It was hypothesized that at least 50 % of lens fits would be successful. METHODS: Eleven sites enrolled contact lens neophytes with up-to-date spectacles. Subjects were fitted bilaterally with a photochromic Test contact lens (ACUVUE® OASYS with Transitions™) for one month of daily, reusable wear. Follow-up visits occurred at 1 week, 2 weeks (lenses replaced), and at 4 weeks after initial dispensing. The investigator judged lens fitting success based on overall assessment of physiology, mechanical fitting, comfort, vision, and handling at the 4-week visit. Following this visit, subjects returned to wearing habitual spectacles for one week and evaluated the performance of the study lens compared to their spectacles. RESULTS: From a total of 127 subjects who were dispensed contact lenses, 105 completed the study per protocol (mean age: 25.5 ± 5.9 years; 57 % female; 80.0 % Caucasian; 71 % with dark iris color). Investigators judged that 97 % of the contact lenses were fitted successfully after 4 weeks of wear; thus, the primary hypothesis was met. Among per-protocol subjects, 60 % reported better vision outdoors, 53 % better vision in changing lighting conditions, 62 % less squinting, and 66 % being less often bothered by bright light. Additionally, 95 % would recommend the lens to others, and 71 % would recommend their eye care practitioner if offered the lens. CONCLUSION: Greater than 95 % of subjects were successfully fitted with the photochromic contact lens based on professional judgement of physiology, mechanical fitting, comfort, vision, and handling. Subjects new to contact lens wear expressed positive opinions for the study contact lenses compared to their up-to-date spectacles.

The Effect of a Photochromic Contact Lens on Visual Function Indoors: A Randomized, Controlled Trial.

SIGNIFICANCE: Photochromic soft contact lenses contain light-sensitive additives that allow them to darken when exposed to ultraviolet or violet light. One question, however, is whether the lenses influence vision indoors (minimally activated). In this study, we found that the minimally activated lenses improved many aspects of visual function under bright light. PURPOSE: Photochromic contact lenses were designed to darken when exposed to outdoor sunlight. The filtering that results improves visual function under bright light conditions. Not all bright light exposures occur outdoors. In this study, we tested whether a photochromic contact lens improved visual function under conditions where the lens was minimally activated (i.e., no more than it normally would be in an indoor environment). METHODS: A subject-masked contralateral design was used comparing a photochromic contact lens randomized to one eye against a nonphotochromic contact in the other eye of the same subject. Sixty subjects (mean = 34.90 ± 11.24 years) were tested. The primary endpoints consisted of four visual function outcomes: photostress recovery, glare disability, glare discomfort, and chromatic contrast. Photostress recovery was quantified by measuring the time needed to recover visual acquisition of a grating target after 5 seconds of an intense xenon white flash exposure; glare disability was evaluated as the energy in a surrounding xenon white annulus necessary to veil a central grating target; and glare discomfort was assessed using bioimaging of the squint response. Chromatic contrast was measured as thresholds for a green-yellow (580 nm) grating target superposed on a blue (460 nm) background. RESULTS: The minimally activated photochromic contact demonstrated improved visual performance compared with the nonphotochromic control across all visual functions tested (P < .01). CONCLUSIONS: Even under conditions of exiguous activation (e.g., as would be expected indoors or while driving at night), a photochromic contact will improve many of the more deleterious aspects of bright light.

Randomized Crossover Trial Evaluating the Impact of Senofilcon A Photochromic Lens on Driving Performance.

SIGNIFICANCE: The first contact lens to incorporate a photochromic additive was cleared by the U.S. Food and Drug Administration last year. Because any ophthalmic lens that absorbs visible wavelengths will reduce retinal illuminance, it is important to understand the impact of this new photochromic contact lens on vision and both daytime and nighttime driving performance. PURPOSE: The purpose of this study was to evaluate the effect of senofilcon A photochromic contact lens wear on vision and driving performance under real-world conditions by comparison with a nonphotochromic contact lens and plano photochromic spectacles. METHODS: In this randomized four-visit bilateral crossover study, 24 licensed regular drivers and established wearers of soft contact lenses were enrolled. Subjects wore in random order each of three study lens types: the investigational photochromic soft contact lens (test), a nonphotochromic soft contact lens (control 1), and plano photochromic spectacle lenses (control 2). Driver performance was assessed on a closed-circuit driving track under challenging controlled conditions. The primary endpoint was overall driving performance score calculated as a composite Z score of six objective metrics. RESULTS: All 24 subjects (mean age, 29.8 years) completed the study. For nighttime driving, the adjusted mean differences in Z score (95% confidence interval) between test and control 1 and between test and control 2 were 0.069 (-0.045 to +0.183) and 0.117 (0.003 to 0.231), respectively. For daytime driving, mean differences were 0.101 (-0.013 to +0.216) between test and control 1 and 0.044 (-0.070 to +0.158) between test and control 2. Results demonstrated noninferiority of the test lens relative to controls for nighttime and daytime driving performance using a noninferiority margin of -0.25 Z score. Noninferiority was also demonstrated on all logMAR and contrast threshold testing. No adverse events were reported during the study. CONCLUSIONS: Study results revealed no evidence of concerns with either driving performance or vision while wearing photochromic contact lenses.

A contra-lateral comparison of the visual effects of a photochromic vs. non-photochromic contact lens.

PURPOSE: To compare the effects of a photochromic contact lens vs. a non-photochromic control lens on visual function. METHODS: A subject-masked, prospective contralateral eye design was used. Sixty-one subjects were enroled based on age (using a 2:1 allocation ratio for ages 18-39 and 40-65 years, respectively). The study lenses were senofilcon A with photochromic additive (Test) that filtered over the entire lens, compared to a non-photochromic Control with no tint. The Test lens was partially activated during testing with a steady-state transmittance of approximately 62%. Eligible subjects were tested using both study lenses, with Test and Control lens randomized by eye. Five visual function outcomes were tested: photostress recovery (PSR), glare disability (GD), glare discomfort (GDC), chromatic contrast (CC) and vernier acuity (VA). Iris colour and macular pigment density were assessed as control variables. PSR was measured as the time needed to recover sight of a target after an intense xenon flash exposure; GD was evaluated as the energy needed to veil a central target by a surrounding xenon annulus; GDC was measured using bio-imaging of the squint response and by self-report using a 9-item Likert scale; CC was measured as thresholds for a yellow grating target superposed on a 460-nm background; VA was determined by measuring vernier offsets of light lines through apertures. RESULTS: Based on our stimulus conditions, PSR was 43% faster using the Test vs. the Control. The eye wearing the Test had 38% less squint (GDC) compared to the Control. GD was improved by 36% in the Test vs. Control and CC was enhanced by 48% with the Test. There was no significant difference in VA. CONCLUSIONS: There was a beneficial influence on visual function when comparing the photochromic with the non-photochromic contact lens. This benefit was seen specifically with respect to PRT, GDC, GD and CC thresholds.