Hydrophilic contact lens spoliation can be associated with the deposition of calcium salts. The relationship between the concentration of calcium in tear fluid and contact lens use has been studied in healthy volunteers and in patients using various forms of hard and soft contact lenses, tear samples being collected with Schirmer strips and with lenses in situ. Methods are suggested for correct...

PURPOSE Soft contact lenses have been reported to increase the progression of myopia. The purpose of this study was to determine whether soft contact lenses affect the progression of myopia in children. METHODS Children between the ages of 8 and 11 years with -1.00 to -6.00 D myopia and less than 1.00 D astigmatism were randomly assigned to wear soft contact lenses (n = 247) or spectacles (n ...

This is a review of the current literature describing the effect of atropine, bifocals, and/or contact lenses on slowing the progression of myopia. Cumulative data from a number of studies have demonstrated atropine instilled once a day in myopic eyes resulted in a 90% average reduction of myopia progression, as compared to untreated eyes, i.e., from 0.50 D/year to 0.05 D/year. Pirenzepine, a m...

Three patients, women aged 69, 25 and 30 years, with refractory keratitis were found to have a rare infection with Acanthamoeba. All wore soft contact lenses. The frequency of Acanthamoeba keratitis increased in recent years. At present, an efficacious antiprotozoal therapy is available, for instance in the form of polyhexamethylene biguanide and propamidine. In cases of refractory keratitis, t...

PURPOSE The purpose of the present study was to develop mathematical relationships that allow obtaining equilibrium water content and refractive index of conventional and silicone hydrogel soft contact lenses from refractive index measures obtained with automated refractometry or equilibrium water content measures derived from manual refractometry, respectively. METHODS Twelve HEMA-based hydr...

Citation: Walther H, Phan C-M, Subbaraman LN, Jones L. Differential deposition of fluorescently tagged cholesterol on commercial contact lenses using a novel in vitro eye model. Trans Vis Sci Tech. 2018;7(2): 18, https://doi.org/10.1167/ tvst.7.2.18 Copyright 2018 The Authors Purpose: We evaluate the differences in lipid uptake and penetration in daily disposable (DD) contact lenses (CL) using ...

A series of 75 spoilt soft lenses with opacities (mostly manifesting as discrete spots or as large areas of cloudiness, chalk-white in appearance) were subjected to histochemical, electron microscopical, electron probe x-ray microanalytical, x-ray diffraction, atomic absorption spectro-photometric, and biochemical analyses. The results showed that in many cases calcium was implicated in the dep...

OBJECTIVE To compare the effects of rigid gas-permeable contact lenses (RGPs) and soft contact lenses (SCLs) on myopia progression in children. METHODS We randomly assigned 116 subjects to wear RGPs or SCLs. Subjects underwent cycloplegic autorefraction, keratometry, and A-scan ultrasonographic axial length measurements at each annual visit. All analyses were conducted according to the origin...

PURPOSE To examine whether corneal hydration control is impaired in corneas with endothelial morphologic changes (increased variation in cell size and cell angularity) due to long-term low gas-permeable contact lens wear. METHODS Twenty-one long-term wearers of low gas-permeable contact lenses (mean age, 41 years +/- 8 SD) and 18 age-matched controls (mean age, 42 years +/- 8 SD) were studied...

PURPOSE A method to measure the tear film beneath a soft contact lens, referred to as post-lens tear thickness (PLTT), would have many applications to contact lens research. In this study a noninvasive technique for measuring the PLTT is presented. METHODS The feasibility of measuring the tear layer by optical pachometry was first assessed using a model eye. The baseline corneal thickness (B)...