[Calcification of hydrophilic acrylic intraocular lenses: clinical and pathological aspects]

The aim of this study was to evaluate the clinical aspects of ten eyes with calcified hydrophilic acrylic intraocular lenses and pathological data obtained from seven explanted lenses.

Forty-seven eyes of 40 patients received the same implant in the first 6-month period of 2001. Ten eyes showed intraocular lens opacification detected 6-18 months after the operation: seven lenses were explanted and three were left in place because they were not causing a decrease in visual acuity or glare at light. Five of ten eyes were diabetic. The explanted lenses were examined under the light microscope and the electron microscope. The elemental analysis of the lens surfaces was made by energy dispersive spectrometry.

The light microscopy showed an irregular surface covered by a gray-white opacity. The electron microscopy detected multiple granulations on the front and back surfaces of the lenses including some portions of the haptics. The size and density of these granulations were smaller on the back surface. The energy dispersive spectrometry showed the presence of calcium and phosphate on both surfaces. The spikes of calcium and phosphate were smaller for the back surface of the lenses.

Calcification was predominantly seen on the surfaces that were in contact with aqueous not covered with anterior capsule. Half (5/10) of the cases were diabetic even though 18% of all patients receiving this lens were diabetic. The presence of diabetes is very common in other series. These data suggest the role of a metabolic factor influencing the milieu of the lens in this calcification process.

Calcification of the hydrophilic acrylic lenses is a relatively serious complication, but the conditions leading to its appearance and the physiopathology have not yet been fully elucidated. The surgeon should be very careful in the choice of the intraocular lens to implant, and even more so if the patient is diabetic.