Novel Contact Lens Manufacturing Technique May Improve Vision Break Up Time

A novel contact lens manufacturing technique may produce a senofilcon A contact lens that can improve focus without reduced vision quality and maintain contrast in silicone hydrogel contact lens wearers, according to a study published in Ophthalmic and Physiological Optics. The technique, which uses double-sided curing, may improve tear film stability, which is essential for providing a smooth refractive surface and maintaining comfort among wearers.

Researchers enrolled 50 habitual contact lens wearers (average age, 29.5 years; 76.6% women) in the randomized, participant-masked investigation conducted at a single center between May and August 2021. The team randomly assigned participants to treatment with the lens manufactured with the novel contact lens manufacturing technique or to a control lens without the double-sided curing technique. After a 2-week dispensing period, participants crossed over to the other contact lens.

Investigators measured vision breakup time (VBUT), modulation transfer function (MTF) cutoff, Strehl ratio, and potential visual acuity for 100% contrast and objective scatter index while participants wore each lens. The team compared metrics between the control lens and the lens made using the novel contact lens manufacturing technique.

The lens utilizing the new manufacturing technique significantly improved VBUT, the report shows. The estimated odds ratio of a VBUT greater than 10 seconds was 1.582 (95% CI, 1.009-2.482; P =.046) in the test lens compared with the control lens. MTF cutoff was also significantly better in the test lens compared with the control lens (P =.049), with a least squares mean difference estimate of 2.243 (95% CI: 0.012-4.475) between the 2 lenses. There were no significant differences in Strehl ratio, potential visual acuity, or objective scatter index between the lenses (P ≤.05) and no serious adverse events were reported.

 “Contact lenses often adversely impact tear film stability, which is the primary cause of dry eye disease,” according to researchers. “The double-sided curing is believed to enable a more optimal distribution of [polyvinylpyrrolidone] throughout the lens, which helps promote increased tear-film stability.” 

Study limitations include a small sample size and single center design.

Disclosure: This research was supported by Johnson & Johnson Vision Care. All study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.