Millenniums update on posterior capsule opacification, (PCO) scores, centration, biocompatibility and fixation of foldable intraocular lenses (IOL) -an analysis of 1,221 peudophakic post mortem globes

Background: The ongoing and fast evolution of foldable IOL designs establis hed the necessity to evaluate the different abilities of each lens style. T he large IOL database (over 16,500 specimens) acquired in our laboratory, h as permitted us to perform a clinico-pathological analysis on pseudophakic autopsy globes provided from sources worldwide, especially many Lions Eye b anks in the United States. Material and methods: We analyzed 6 foldable IOL styles commonly implanted in the United States, using one type of rigid IOL design (1-piece design ri gid PMMA optics) as a comparison group. Posterior capsule opacification (PC O) score, decentration, fixation, presence or absence of a Nd:YAG laser pos terior capsulotomy and area and intensity of Soemmerring's ring formation w as discerned by examination under an operating microscope using the Miyake- Apple posterior photographic technique. Results: The four lenses with the lowest rates ranging between 3.8% and 21. 7% are modern designs, mostly implanted after 1992. The two lenses with the higher rates ranging between 23.1% and 30.4%, were all older designs, alre ady prevalent prior to 1992. IOL fixation with both haptics in the capsular bag showed the best centration values and PCO scores. Our studies to date have shown in a preliminary fashion that the AcrySof(TM) IOL displays the t he lowest (best) biocompatibility score. Conclusions: Entering the new millenium, with evolution of modern surgical techniques and IOL designs, the incidence of the two major complications of cataract surgery, decentration and PCO are now finally diminishing.