The effects of a senofilcon A contact lens with and without a photochromic additive on positive dysphotopsia across age
John R Buch O.D. M.S. F.A.A.O.
David Ruston BSc FCOptom DipCL FAAO FIACLE
John Meyler BSc FCOptom DipCL
Jessica Lin Cannon MSc.
Purpose: The purpose was to assess the visual effects of wearing an activated and an inactivated photochromic lens (Test), with direct comparisons to a non-photochromic lens (Control), in terms of their ability to reduce positive dysphotopsia (halos, starbursts). Attention is given to the influence of age.
Method: Two age groups (13-39, 40-65) were recruited in a 2:1 ratio at a single investigational site. Subjects were randomly fit with a photochromic lens on one eye and a non-photochromic lens on the other. Testing occurred without and with photochromic activation by use of a violet activator (390 nm, half-bandwidth 30 nm). The extent of dysphotopsia was measured using an aperture (~4 mm) that created a bright point source of light 38 inches from the plane of the eye. Between the point source and subject, a centering precision caliper was used to measure lateral spread of halos and starbursts.
Results: A total of 54 subjects completed as cohort (younger group: n=35 age 28.0 +/- 6.28, older group: n=19 age 47.6 +/- 5.93). The photochromic lens produced smaller halo diameters than the Control lens, both activated (48% on average) and inactivated (18% on average), and age strata was a significant factor (p<0.001) with the older group showing a greater reduction. The photochromic lens produced smaller starburst diameters than the Control lens, both activated (42% on average) and inactivated (22% on average), and age strata was a significant factor (p=0.001) with the older group showing a greater reduction.
Conclusions: The senofilcon A lens with photochromic additive reduced the extent of positive dysphotopsia compared to the same lens without the additive, regardless if the lens was activated or not. The visual benefit was greatest with the older population.
1st Author Biography: Dr. John Buch is a Senior Principal Research Optometrist for Johnson & Johnson Vision Care and a Fellow of the American Academy of Optometry. John received his O.D. degree from The Ohio State University and his M.S. degree from the Indiana University. His thesis investigated the effect that contact lens designs have on ocular surface physiology. Since joining J&J in 1998, John has been the clinical project lead on several marketed products, most recently ACUVUE OASYS with Transitions. He has a research interest in the psychophysical and neurobiological basis of visual perception and the clinical evaluation of contact lens performance.
*Data correct at the time of submission to BCLA by NCC.