The adhesive force between the intraocular lens (IOL) and posterior capsule (PC) is likely influenced by the ability to adsorb fibronectin, according to a study published in Experimental Eye Research. A tight bond between the IOL and PC may lead to a decrease in cell infiltration, lowering the incidence of posterior-capsule opacification (PCO).
Investigators used a PCO predictive in vitro model to assess the adhesive force between the IOL and PC and a macromolecular dye imaging model to determine cell infiltration. They constructed simulated models of PCs cross-linked with glutaraldehyde and folded them into spherical, cup-like structures. The team placed the structures into petri-dishes and placed one of the following IOLs into the mix: acrylic foldable (21.0 D), polymethylmethacrylate (PMMA) (23.5 D), or silicone (26.0 D). The team used a diglyme coating on the IOLs to reduce protein adsorption and test its ability to alter adhesion force and cell infiltration.
The investigators found that fibronectin increased the adhesion force of acrylic-foldable IOLs (1.408±0.158 to 2.346±0.149 mN) while decreasing the adhesion forces of the PMMA (0.409±0.06 to 0.334±0.0.081 mN) and silicone IOLs (1.136±0.153 to 1.114±0.081 mN). However, they determined that the influence of fibronectin on the IOL:PC adhesion force of PMMA and silicone IOLs was not statistically significant, according to the report. The team suggests that this increased adhesion may be responsible for the lower incidence of PCO reported in patients with acrylic-foldable IOLs.
“The overall results suggest that fibronectin adsorption increases the adhesion force of acrylic foldable IOLs and the PC,” according to the investigators. “Such strong IOL:PC adhesion force of acrylic foldable IOLs may be responsible for reducing the extent of cell infiltration and the incidence rate of PCO.”
Study limitations include the use of simulated models and different dioptric powers between the IOLs.
Jaitli A, Roy J, Chatila A, Liao J, Tang L. Role of fibronectin and IOL surface modification in IOL: lens capsule interactions. Exp Eye Res. Published online June 1, 2022. doi:10.1016/j.exer.2022.109135