chemical structure and optical properties of hydrophilic and hydrophobic intraocular lenses

purpose: to compare the optical properties of hydrophilic and hydrophobic intraocular lenses (iols) containing uv-absorber and to determine their chemical composition. methods: 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. results: 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. conclusion: 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.