[Chemical structure and optical properties of hydrophilic and hydrophobic intraocular lenses]

To compare the optical properties of hydrophilic and hydrophobic intraocular lenses [IOLs] containing UV-absorber and to determine their chemical composition. Optical properties of different foldable hydrophilic and hydrophobic as well as non-foldable hydrophobic polymethylmetacrylate [PMMA] IOLs were evaluated in three powers of 15, 22 and 25 diopters. Optical properties were measured using UV-VIS [UV-Visible] spectroscopy between wavelengths 200 and 800 nm and chemical structure characteristics were determined by ATR [attenuated total reflectance] spectroscopy. ATR spectroscopy revealed that foldable hydrophilic and hydrophobic IOLs and non-foldable hydrophobic IOLs were respectively composed of hydroxyethylmethacrylate, a copolymer of phenylethylacrylate and phenylethylmethacrylate, and PMMA [in accordance with manufacturer's claim]. Cut-off points of the lenses were found to be around 350-420 nm. Increasing the IOL power from 15 to 22 diopters did not significantly change the cut-off points of foldable hydrophobic IOLs, however a considerable cut-off shift to higher wavelengths was noted when power increased to 25 diopters. PMMA lenses showed a constant cut-off at 400 nm for all power values. The increase in power is associated with absorption of lower energy UV radiation and shift of cut-off points to higher wavelengths in hydrophobic IOLs but with no considerable effect on cut-off points in PMMA IOLs

Ocular dirofilariasis, a case report

Accidental infection with animal filarial worms in humans is a dilemma for clinicians and parasitologists throughout the world. To date a variety of such rare parasitoses have been reported mostly in tropics and subtropics. Human dirofilariasis is among those unusual zoonotic infections that occasionally have been observed in the eye and in subcutaneous areas exhibiting with nodule for mation. Filarial worms are transmitted to humans through invertebrate biological vectors such as certain species of mosquitoes. The present report describes a peculiar case of ocular dirofilariasis in a 49-year-old man resident in Iran