The use of hydrophilic soft contact lenses for dispensation of pilocarpine is described. The release rate of pilocarpine from three materials of different water content was estimated and from this the surface concentrations were calculated. It is estimated that PolyHEMA can after 15 hours provide a 1 per cent surface concentration of pilocarpine, whereas higher water content materials (70 and 8...

PURPOSE To evaluate the visual performance by high contrast visual acuity, contrast sensitivity and wavefront in myopic patients with or without astigmatism corrected with spectacles and with three different soft contact lenses [Acuvue 2 (Vistacon J&J Vision Care Inc., USA), Biomedics 55 (Ocular Science, USA), and Focus 1-2 week (Ciba Vision Corporation, USA)]. METHODS An interventional prosp...

Adhesion of pathogenic microbes, particularly bacteria, to contact lenses is implicated in contact lens related microbial adverse events. Various in vitro conditions such as type of bacteria, the size of initial inoculum, contact lens material, nutritional content of media, and incubation period can influence bacterial adhesion to contact lenses and the current study investigated the effect of ...

We demonstrate that a modified point diffraction interferometer can be used to measure the power distribution of different kinds of ophthalmic lenses such as spectacles, rigid and soft contact lenses, progressive lenses, etc. The relationship between the shape of the fringes and the power characteristics of the component being tested is simple and makes the design a very convenient and robust t...

Corneal thickness changes were monitored in ten subjects (1) over a 36-hour period without contact lens wear and (2) during 7 days continuous wear of three types of hydrogel contact lenses of different back vertex powers. Measured on awakening, the mean overnight central corneal edema without lenses was 3.0% ± 1.2%. With the lenses used in this study, the mean overnight corneal swelling over th...

Lens fiber cell gap junctions contain alpha(3) (Cx46) and alpha(8) (Cx50) connexins. To examine the roles of the two different connexins in lens physiology, we have genetically engineered mice lacking either alpha(3) or alpha(8) connexin. Intracellular impedance studies of these lenses were used to measure junctional conductance and its sensitivity to intracellular pH. In Gong et al. 1998, we d...

BACKGROUND The goal of this investigation was to correlate particular age-related structural changes (compaction) to the amount of scatter in rabbit lenses and to determine if significant fiber compaction occurred in the nuclear and inner cortical regions. METHODS New Zealand White rabbits at 16-20 months old (adult; n = 10) and at 3.5-4 years old (aged; n = 10) were utilized for this study. ...

Albumin surface deposits were significantly higher on contact lenses from subjects with CLPC (p<0.0001, Figure 5). m Lenses from six of the CLPC subjects were analysed prior to the event. There was no difference in the amount of HSA on these lenses compared to the CLPC lenses. m Lactoferrin amounts were not significantly different between the CLPC and non-CLPC groups (Figure 6). m The amount of...

PURPOSE The purpose of this pilot study was to evaluate the effect of magnification lenses on the indirect vision skills of dental hygiene students. METHODS This pilot study examined the accuracy and efficiency of dental hygiene students' indirect vision skills while using traditional safety lenses and magnification lenses. The sample was comprised of 14 students in their final semester of a...

Keratoconus is a progressive, non-inflammatory corneal ectasia characterized by thinning and weakening of the corneal stroma which results in its' protrusion. The onset is during puberty and progresses until the fourth decade of life. In earlier stages, good visual acuity can be provided with spectacles. With progression, contact lenses are considered to be a better therapy. Aim of this study w...