Chemical microanalysis of mineral deposits on explanted hydrophilic acrylic intraocular lenses

Abstract

The two samples represent two stages of a single process. The early stage is associated with newly formed HA crystals that are unable to cause any significant changes to the lens surface. However, as spherocrystals grow, they exert a crystallization effort that moves their growth centers apart with subsequent lens rupture and deformation. Crystal morphology undergoes dynamic changes: while primary (newly formed) crystals are sheaf-like, mature are spheres. A growing HA is non-stoichiometric. Zinc abundance accounts for appearance of its separate mineral phase. Hydrophilic properties of acrylic polymer determine its high affinity for HA crystals. Hydrophobic coating (sample no.1) does not completely prevent lens opacification due to mineral deposits on its surface.

Large-scale opacification of a hydrophilic/hydrophobic intraocular lens

“…Opacification of hydrophilic IOLs with hydrophobic coating was first described in 2012, and several case reports have been published since then. [10][11][12][13][14] In this cohort, we evaluated 154 eyes implanted with LS-502-1 and found an opacification prevalence of 53.3% (n = 90). To the best of our knowledge, this is not only the largest case series of opacified hydrophilic/hydrophobic IOLs, but also the highest opacification rate ever described for any type of IOL.…”

Variation in intraocular lens calcification under different environmental conditions in eyes with supplementary sulcus-supported lenses

“…Calcification of intraocular lenses is a dynamic process. 31 Previously, studies suggested that early stages of newly formed crystals are unable to cause any significant changes to the lens surface, whereas later stages of crystallization can lead to subsequent lens rupture and deformation. 31 Lin et al found mainly poorly-formed crystalline, immature non-stoichiometric deposits in an opacified Hydroview H60 M IOL (Bausch & Lomb, Clearwater, USA) that was in the eye for two years.…”

“… 31 Previously, studies suggested that early stages of newly formed crystals are unable to cause any significant changes to the lens surface, whereas later stages of crystallization can lead to subsequent lens rupture and deformation. 31 Lin et al found mainly poorly-formed crystalline, immature non-stoichiometric deposits in an opacified Hydroview H60 M IOL (Bausch & Lomb, Clearwater, USA) that was in the eye for two years. 32 Avetisov et al proposed that calcifications mainly consist of Tricalcium Phosphate [ ] with Zinc impurities possibly playing a role in the calcification process.…”

“… 32 Avetisov et al proposed that calcifications mainly consist of Tricalcium Phosphate [ ] with Zinc impurities possibly playing a role in the calcification process. 31 In the present study we used a new approach to characterize the Calcium Phosphate deposits by the means of ED pattern analysis. In an IOL that was inside of the eye for more than 5 years (case 7), we could show that the crystals consist of a mature Hydroxyapatite where we could identify the chemical composition as .…”

Current Developments in Monofocal Intraocular Lens Technology

“…But capsular biocompatibility of hydrophilic acrylic IOL is low. Capsular biocompatibility is very important because it effects long term visual outcomes negatively through posterior capsular opacification (PCO) and deformation of IOL surface [6] . For this reason, the most of the cataract surgeons use more common hydrophobic acrylic IOL than hydrophilic acrylic IOL if possible.…”