Hydrophobic surface properties of hydrophilic acrylic lenses do not protect against calcification

Abstract

Opacification through calcification of hydrophilic acrylic intraocular lenses is aserious complication of cataract surgery, which usually results in explantation of the lens. In the process of calcification, the intraocular lens material plays acrucial role: calcification only occurs in hydrophilic acrylic lenses. Hydrophobic acrylic lenses show no crystal formation within the polymer. Hydrophilic acrylic lenses from some manufacturers have hydrophobic surface properties. The question arises as to what influence these surface properties have on the risk of calcification. The present study investigated whether the hydrophobic surface properties of hydrophilic acrylic lenses can prevent calcification. Using an electrophoretic in vitro model of calcification, two hydrophilic lenses with hydrophobic surface properties were compared to two hydrophilic lenses and ahydrophobic negative control to determine the risk of calcification. The lenses were then analyzed by optical microscopy, Alizarin Red and Von Kossa staining, scanning electron microscopy (SEM) and energy dispersive X‑ray spectroscopy (EDX). All four hydrophilic lens models showed calcification within the polymer. No difference was found between the hydrophilic lenses and the hydrophilic lenses with hydrophobic surface properties in terms of crystal formation. The hydrophobic negative control showed no calcification. The investigation conducted in this study under standardized conditions could show that hydrophobic surface properties of hydrophilic acrylic lenses do not protect against calcium phosphate crystal formation within the polymer. There also is arisk of calcification in these lens models.