We describe a technique for making an optimal flange in intraocular lenses (IOLs) used for flanged intrascleral IOL fixation. The flange shape varies in poly(methyl methacrylate) (PMMA) haptics of different IOLs of different manufacturers. We identified the distance between the forceps grip of the haptic and the end of the haptic during heating with a cauter as a critical factor for the optimal flange shape in 5 PMMA haptics but not in 2 polyvinylidene fluoride haptics.

The purpose of this study was to investigate if topically applied caffeine protects against in vivo ultraviolet radiation cataract and if so, to estimate the protection factor. Three experiments were carried out. First, two groups of Sprague-Dawley rats were pre-treated with a single application of either placebo or caffeine eye drops in both eyes. All animals were then unilaterally exposed in vivo to 8 kJ/m2 UV-B radiation for 15 min. One week later, the lens GSH levels were measured and the degree of cataract was quantified by measurement of in vitro lens light scattering. In the second experiment, placebo and caffeine pre-treated rats were divided in five UV-B radiation dose groups, receiving 0.0, 2.6, 3.7, 4.5 or 5.2 kJ/m2 UV-B radiation in one eye. Lens light scattering was determined after one week. In the third experiment, placebo and caffeine pre-treated rats were UV-B-exposed and the presence of activated caspase-3 was visualized by immunohistochemistry. There was significantly less UV-B radiation cataract in the caffeine group than in the placebo group (95% confidence interval for mean difference in lens light scattering between the groups = 0.10 ± 0.05 tEDC), and the protection factor for caffeine was 1.23. There was no difference in GSH levels between the placebo- and the caffeine group. There was more caspase-3 staining in UV-B-exposed lenses from the placebo group than in UV-B-exposed lenses from the caffeine group. Topically applied caffeine protects against ultraviolet radiation cataract, reducing lens sensitivity 1.23 times.

ABSTRACT.Purpose: To investigate whether infrared radiation (IRR)-induced cataract is instant or is associated with a time delay between the exposure and the onset of lens light scattering after an exposure to just above threshold dose. Methods: Six-weeks-old albino Sprague-Dawley female rats were unilaterally exposed to 197 W/cm 2 IRR at 1090 nm within the dilated pupil. In the first experiment, the animals were exposed with four exposure times of 5, 8, 13 and 20 second, respectively. At 24 hr after exposure, the light scattering in both exposed and contralateral not exposed lenses was measured. Based on the first experiment, four postexposure time groups were exposed unilaterally to 1090 nm IRR of 197 W/cm 2 for 8 second. At 6, 18, 55 and 168 hr after exposure, the light scattering in both lenses was measured. Results: A 197 W/cm 2 IRR-induced light scattering in the lens with exposures of at least 8 second. Further, after exposure to IRR of 197 W/cm 2 for 8 second, the light-scattering increase in the lens was delayed approximately 16 hr after the exposure. Conclusion: There is a time delay between the exposure and the onset of cataract after exposure to close to threshold dose implicating that either near IRR cataract is photochemical or there is a time delay in the biological expression of thermally induced damage.