Optic edge design as longterm factor for posterior capsular opacification rates

Objective: To compare the difference in posterior capsular opacification (PCO) between highly refractive silicone and hydrophobic acrylic foldable intraocular lenses (IOLs) with sharp and round edge designs 3 years after in-the-bag IOL implantation in subjects undergoing bilateral cataract surgery. Design: Open-label, prospective, randomized, multicenter clinical trial. Participants: Two hundred and eighty-eight patients with bilateral surgery for senile cataract operated in German university clinics, eye hospitals, and private ophthalmic surgical centers (Aachen, Ahaus, Bad Hersfeld, Frankfurt/Main, Jena, Rosenheim, and Sulzbach/Saar). Interventions: At each center, a highly refractive index silicone IOL with a sharp optic edge (CeeOn) was intraindividually compared either with a high-refractive index silicone IOL with a round optic edge (PhacoFlex) in 108 patients or with an acrylic IOL with a sharp optic edge (AcrySo in 139 patients. All patients received standard phacoemulsification with IOL implantation in the bag in both eyes from the same surgeon. A morphological evaluation of PCO was performed by the Evaluation of the Posterior Capsule Opacification (EPCO) system 1 to 2 weeks and 11 to 14 and 35 to 37 months after surgery. The blinded digital pictures were evaluated by an independent investigator. Posterior capsular opacification was statistically evaluated by paired comparisons of 3-year cumulative incidences of neodymium:yttrium-aluminum-garnet (Nd:YAG) laser treatment and EPCO scores. Main Outcome Measures: Posterior capsular opacification. Results: The 3-year cumulative incidences of Nd:YAG laser capsulotomy were 2.1% (CeeOn), compared with 2.1% (AcrySof) (risk difference, 0%; 90% confidence interval, -3.4% to 3.4%), and 5.7% (CeeOn), compared with 17.0% (PhacoFlex) (risk difference, -11.4%; 90% confidence interval, -18.1% to -4.7%). In patients without Nd:YAG laser treatment, medians of the total area EPCO score were 0.0005 (CeeOn) versus 0.0440 (AcrySo and 0 (CeeOn) versus 0.0700 (PhacoFlex) at 3 years. Functional results, safety, and handling did not significantly differ for the 3 lenses. Conclusions: Our results suggest that modern foldable IOLs have a low incidence of PCO after 3 years. There is less PCO for sharp optic edge designs independent of IOL material.