Quality Control and Ultrastructural Evaluation of Surface-modified Intraocular Lenses in vitro by Atomic Force Microscopy

Objective: This study was aimed at answering the question whether surface-passivated intraocular lenses (IOL) have a smoother surface structure than ordinary PMMA IOL, since the surface roughness of PMMA is known to have an influence on the attachment of cells and bacteria to the material. Material and Methods: High-resolution surface analysis was performed in ordinary (n = 5) and surface passivated (n = 6) PMMA IOL using the atomic force microscope. Results: The mean roughness R_a was calculated to be 3.556 ± 0.334(S.D.) nm for the surface-passivated IOL and 2.743 ± 0.109(S.D.) nm for the unmodified PMMA IOL. Conclusion: This study demonstrated that surface passivated IOL were not smoother than unmodified IOL, but showed a significantly rougher surface than ordinary PMMA IOL. Possible clinical implications of our study are discussed in connection with other in vitro and clinical biocompatibility studies.