IN-VITRO ADHERENCE OF PSEUDOMONAS-AERUGINOSA TO 4 INTRAOCULAR LENSES

Purpose: To compare the relative degrees of adherence of a clinical st rain of Pseudomonas aeruginosa to the optic material of four intraocul ar lenses (IOLs). Setting: Center for Applied and Environmental Microb iology, Georgia State University, Atlanta, Georgia, USA. Methods: Intr aocular lens optics made of poly(methyl methacrylate) (PMMA), AcrySof( R)-acrylic, and silicone were included in this study. The IOLs were in cubated in a minimal medium with cells of P. aeruginosa for 2 hours an d 18 hours. Cells in the 2 hour experiment were prelabeled with H-3-le ucine; those in the 18 hour experiments were postlabeled. After rinsin g the IOLs to remove loosely adherent cells, we determined the number of cells adhered to coded lenses from calibration curves of disintegra tions per minute versus cells per square millimeter. Additional lenses were incubated with P. aeruginosa and examined with scanning electron microscopy. Results: The adherence of P. aeruginosa in order of incre asing magnitude was AcrySof-acrylic < PMMA < silicone 1 < silicone 2. The differences between all groups were statistically significant. The scanning electron microscopy observations were in general agreement w ith the radiolabel studies. Conclusions: The AcrySof-acrylic IOL was l ess susceptible to primary adherence and 18 hour biofilm formation by P. aeruginosa than the PMMA and silicone IOLs, indicating that this ma terial reduced pseudomonad adherence and the risk of endophthalmitis f ollowing cataract surgery.