Clinical Ophthalmology (Sep 2020)
In vitro Evaluation of the Location of Cholesteryl Ester Deposits on Monthly Replacement Silicone Hydrogel Contact Lens Materials
Abstract
Han Qiao,1 Doerte Luensmann,1 Miriam Heynen,1 Elizabeth Drolle,1 Lakshman N Subbaraman,1 Charles Scales,2 Donald Riederer,2 Zohra Fadli,2 Lyndon Jones1,3 1Centre for Ocular Research & Education (CORE), School of Optometry & Vision Science, University of Waterloo, Waterloo, ON, Canada; 2Johnson & Johnson Vision Care, Inc, Jacksonville, FL, USA; 3Centre for Eye & Vision Research (CEVR), Hong Kong, People’s Republic of ChinaCorrespondence: Doerte Luensmann Email [email protected]: The deposition profile of cholesteryl ester on the surface and throughout the matrix of silicone hydrogel contact lens (CL) materials was determined under conditions that mimic a daily wear regimen.Methods: In this in vitro study, four SiHy CL materials (senofilcon C, lotrafilcon B, comfilcon A and samfilcon A) were incubated in an artificial tear solution (ATS) for up to 30 days. CL incubation was alternated between the ATS (16 hours) and a multipurpose care regimen (8 hours). The ATS included fluorescently tagged cholesteryl ester (5-cholesten-3ß-ol 6-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]caproate; CE-NBD) and confocal laser scanning microscopy visualized the distribution of the lipid through the CLs.Results: The distribution of CE-NBD was homogenous from the anterior to posterior surface in senofilcon C and comfilcon A, at all time points. For lotrafilcon B and samfilcon A, CE-NBD localization was heterogeneous, with greater amounts on the surfaces on Day 1 and Day 14 compared to the lens matrix; however, differences in concentration between the surface and bulk diminished by Day 30.Conclusion: The distribution of the non-polar lipid CE-NBD varied with lens material chemistry. While some lens materials deposited the lipid primarily on the surface after 16 hours of exposure, all materials exhibited a homogenous distribution after one month.Keywords: lipid distribution, silicone hydrogel contact lenses, cholesteryl ester, artificial tear solution