Influence of Lens Power on IOL:Posterior Lens Capsule Interactions and IOL’s Posterior Capsule Opacification Potential

Abstract

Purpose : Severe myopic eyes have been associated with high PCO incidence. While it has been reported that myopic eyes have weaker or more delayed capsule adhesion than emmetropic eyes, it is unclear whether and how IOL diopter degree has a significant impact on PCO potential. Recent studies show that high IOL affinity to the posterior lens capsule (PLC) negatively impacts PCO potential by impeding lens epithelial cell (LEC) infiltration and proliferation. It is possible that IOL power may affect IOL affinity for the PLC and their PCO potential.

Methods : A 3D simulated PLC (sPLC) with human dimensions (equatorial diameter 9 mm, curvature 90°) and acrylic foldable IOLs of 6.0 D, 20.0 D, and 30.0 D (6 mm optic diameter) were used. By placing IOLs in sPLC for different time periods, the IOL:sPLC adhesion force and interface closure rates were quantified using an adhesion force apparatus and optical coherence tomography (OCT), respectively. By seeding human LEC line HLEB-3 either on the edge of the IOL:sPLC interface or on the surface of sPLCs prior to IOL placement, we then assessed the influence of IOL power on cell infiltration and proliferation at the IOL:sPLC interface, respectively. Metabolic activities of the cells were assessed using Ki-67 staining.

Results : We found that dioptric power has a significant impact on IOL:sPLC adhesion force, which are in the following order: 30D IOL (low myopia) ≈ 20D > 6D (high myopia). OCT images also show that the spaces between the IOL and sPLC are in the reverse order of adhesion force, suggesting that high adhesion force and tight binding between the IOL and sPLC contribute to small interface spaces. Finally, as expected, IOLs with higher powers (20D and 30D) were associated with the least extent of LEC infiltration (Fig. 1), proliferation, metabolic activity, and differentiation among all IOLs tested.

Conclusions : The overall results suggest that the low PLC binding affinity of low-power IOLs for high myopia is responsible for high interface space, LEC responses, and PCO incidence rates. The overall findings also show that increasing IOL affinity for PLCs may be a useful tactic for lowering PCO formation and enhancing IOL safety.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.

 

Fig. 1: LEC infiltration with IOL Power. A) Representative cross-sectional OCT images at IOL:sPLC interface (green arrows, LECs). B) Quantification of LEC infiltration from edge to center of IOL: sPLC interface.