Late Opacification of Hydrophilic Acrylic Intraocular Lenses

ABSTRACT

PURPOSE: To report clinical, pathological, histochemical, ultrastructural, and spectrographic analysis of explanted hydrophilic acrylic intraocular lenses (IOLs). By IOL extraction and new IOL implantation, patients resulted in increased visual acuity. METHODS: Four hydrophilic acrylic IOLs (ACRL-C160,Opthalmed(R),California,USA)were explanted from the 3 patients who had developed decreased visual acuity after about 5months from uneventful phacoemulsification and IOL implantation. Four IOLs were examined by gross and light microscopy. Staining of IOLs was performed with 1% alizarin red and von Kossa method (both stains for calcium). Some were submitted for scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Infrared spectral analysis (IR), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS). RESULTS: Microscopic analysis showed opaque materials on explanted IOL surface. The deposits were stained positive with Alizarin red and the von Kossa method for the detection of calcium. SEM revealed IOL surface covered by calcium crystals and collagen fibers. Many studies such as XPS, IR, EDS showed that the causes of opacification of IOLs were calcium phosphate hydroxide (hydroxyapatite). We suspect silicone promoted this reaction as catalyst. CONCLUSIONS: This is the rarest cases and clinical, pathological and spectroscopic report of opacified hydrophilic acrylic IOLs (ACRL-C160,Opthalmed(R),California,USA). We found out materials causing opacification by many special studies. Additional studies should be done to determine possible mechanisms and biocompatibility of the IOLs materials containing UV absorbable coating materials, packaging system and foldable systems in the intraocular conditions