Assessing intraocular lens calcification in an animal model

Abstract

Material calcification occurred more quickly in an intramuscular or subcutaneous environment than in an intraocular environment. Intramuscular and subcutaneous implantation appears to be an excellent model for screening materials for calcification potential. However, calcification is both host environment and material dependent. Using intramuscular or subcutaneous implantation in animal models to predict intraocular calcification in humans must be done with caution.

Calcification of Hydroview H60M intraocular lenses: Aqueous humor analysis and comparisons with other intraocular lens materials

“…We believe hydrophilic acrylic materials may lead to calcification as it has been reported that HEMA-based IOL materials calcified within animal muscles in an experimental comparison of materials. 28 The findings in experiment 3 suggest that hydrophilic acrylic IOLs are likely to develop calcification when the concentrations of Ca, P, and albumin in the aqueous humor fluctuate due to BAB breakdown or other factors. Therefore, we believe that long-term observation is necessary after implantation of hydrophilic acrylic IOLs, especially in cases in which BAB breakdown is suspected.…”

In Vitro Drug-Induced Spoliation of a Keratoprosthetic Hydrogel

“…Opacification of IOLs manufactured from a copolymer of HEMA and methyl methacrylate (MMA) (Vista Optics, UK) and distributed by MDR Inc (USA) was reported in 9 patients, 11 but it was implied 12 that the bulk opacification in these IOLs was a result of premature aging of the UV-blocking agent included in the polymer rather than of calcification. In another study, 13 the intramuscular and subcutaneous dystrophic calcification of 5 different IOL materials was assessed in rabbits, and calcification was noted in PHEMA. Many recent examples [14][15][16][17][18][19][20][21][22][23] of IOL failure as a result of calcification refer to the implantation of Hydroview™ IOL (Bausch & Lomb, USA), manufactured from a hydrogel copolymer of HEMA and 6-hydroxyhexyl methacrylate.…”

Resultados da troca de lente intra-ocular de hidrogel opacificada

“…A ocorrência de opacificação das lentes intra-oculares de hidrogel foi relatada pela primeira vez em 1987 (9) . Esta opacificação é um fenômeno multifatorial que envolve as característi-cas do material e o seu meio de conservação (2,9) , e, recentemente, vem sendo uma importante indicação para explantação e substituição da lente opacificada (5,8) .…”

“…Esta opacificação é um fenômeno multifatorial que envolve as característi-cas do material e o seu meio de conservação (2,9) , e, recentemente, vem sendo uma importante indicação para explantação e substituição da lente opacificada (5,8) . No presente estudo, o tempo decorrido entre o implante da lente e a percepção de piora da visão pelo paciente variou de 6 a 23 meses (média de 16,4 meses).…”