PURPOSE The aim of this study was to analyze surface changes of three silicone-hydrogel contact lenses after daily wear. The lenses used in this study were balafilcon A, lotrafilcon B (both surface-treated), and galyfilcon A (non surface-treated). METHODS To understand how and where proteins, lipids, and other contaminants change contact lenses, surface roughness was assessed through Atomic F...

Introduction Hydroxyethylmethacrylate (HEMA) is a hydrop~ylic absorpt1ve hydrogel of good mechanical strength which can, in the dehydrated state, he la;the cut to accura'te dimensioIlls and then rehydrated to form a softconta,et Jens of excellent optical properties. Lenses intended for correction .of ametropia (usually myopia) have a water content of 30 per cent to 40 percent hut the ma:terial ...

Within a few minutes of wear, contact lenses become rapidly coated with a variety of tear film components, including proteins, lipids, and mucins. Tears have a rich and complex composition, allowing a wide range of interactions and competitive processes, with the first event observed at the interface between a contact lens and tear fluid being protein adsorption. Protein adsorption on hydrogel ...

Lenses and quasi-lenses on a space X form models of erratic non-determinism. When is equipped with quasi-metric d, there are natural quasi-metrics dP dPa the X, which resemble Pompeiu-Hausdorff metric (and contain it as subcase when d metric), tightly connected to Kantorovich-Rubinstein dKR dKRa Parts I, II III, through an isomorphism between so-called discrete normalized forks. We show that co...

PURPOSE To evaluate the optical power profiles of commercially available soft multifocal contact lenses and compare their optical designs. METHODS The power profiles of 38 types of multifocal contact lenses-three lenses each-were measured in powers +6D, +3D, +1D, -1D, -3D, and -6D using NIMO TR1504 (Lambda-X, Belgium). All lenses were measured in phosphate buffered saline across 8 mm optic zo...

PURPOSE A new method for the measurement of ultraviolet radiation that reaches the surface of the eye is described. METHODS The technique uses contact lenses produced from the ultraviolet-sensitive plastic polysulfone. Two types of polysulfone contact lenses (9 mm and 12 mm in diameter) were manufactured from a polysulfone rod. The 9-mm polysulfone contact lens could be calibrated and used to...

PURPOSE There is increasing interest in fitting children with soft contact lenses. This review collates data from a range of studies to estimate the incidence of complications, specifically corneal infiltrative events and microbial keratitis, in patients under the age of 18 years. METHODS Peer-review papers were identified using PubMed and the Web of Science. A broad range of studies are summ...

BACKGROUND & OBJECTIVES With increasing use of soft contact lenses the incidence of contact lens induced infections is also increasing. This study was aimed to assess the knowledge of new and existing contact lens users about the risk of microbial contamination associated with improper use and maintenance of contact lenses, type of microbial flora involved and their potential to cause ophthalmi...

The greater utilization of soft contact lenses calls for the development of new and objective methods of evaluating the optical performance of the different lens types, in situ. We used videokeratography to examine the surface topography of soft contact lenses that had been worn for more than 1 year on 27 eyes of 23 patients, and compared the resulting color-coded maps and topographic indices a...