The Effect of Nonpreserved Care Solutions on 12 Months of Daily and Extended Silicone Hydrogel Contact Lens Wear

Department of Ophthalmology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
Investigative Ophthalmology &amp Visual Science (Impact Factor: 3.4). 01/2008; 49(1):7-15. DOI: 10.1167/iovs.07-0940
Source: PubMed


To determine the effects of nonpreserved care solutions on human corneal epithelium in long-term daily wear (DW) compared with overnight (extended) wear (EW) of hyper-oxygen-permeable silicone hydrogel contact lenses.
This was a prospective, randomized, double-masked, single-center, parallel treatment group clinical trial (NCT 00344643). One hundred twenty-one patients completed the 13 month study: (1) Lotrafilcon A (30 night EW, n = 29; DW, n = 32); (2) Galyfilcon A (DW, n = 20); and (3) Lotrafilcon B (6 night EW, n = 20; DW, n = 21). Irrigation chamber collection of corneal surface cells (OD) and confocal microscopy (OS) were performed at baseline, 1 week; and 1, 3, 6, 9, and 12 months of EW. The main outcome measures were: (1) Pseudomonas aeruginosa (PA) binding to exfoliated corneal surface cells; (2) central epithelial thickness (CET); and (3) epithelial surface cell exfoliation rate (desquamation).
DW had no significant effect on CET; there was a decrease in CET with EW that recovered (adapted) over 1 year (Lotrafilcon B, P < 0.05). All lens wear (DW, EW) decreased desquamation with adaptive effects over 1 year (P < 0.001). There was no significant difference in PA binding between lenses or modality of wear.
PA binding to corneal epithelial cells is a prerequisite for infection, and no binding indicates no lens-enhanced risk of infection. In contrast to prior studies of preserved lens-care products, the absence of a change in the PA binding data results predict that the risk for PA CTL-keratitis should be similar for daily and extended silicone hydrogel lens wear over 1 year when preservative-free care solutions are used.

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Available from: Walter Matthew Petroll, Jul 11, 2014
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    • "To further examine the effect of preserved solutions on PA adherence, the most recent clinical trial evaluated 121 silicone hydrogel lens wearers using hydrogen-peroxide based solutions in both daily and 6/30 night extended wear over one year. In agreement with the 3 month data, the use of a nonpreserved hydrogen peroxide-based solution in this study eliminated the increase in PA binding that was seen with MPS usage (Ren et al 1999; Robertson et al 2008). Irrespective of differences in PA binding, corneal epithelial homeostasis was still altered, with decreases seen in epithelial desquamation and central epithelial thickness similar to that of previously reported studies; no adaptive effects of either daily or extended wear were seen. "
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