Analysis of intraocular lens surface properties with atomic force microscopy

Abstract

Atomic force microscopy was effective and accurate in analyzing IOL optics. The surface topography of IOLs may vary with different manufacturing processes.

Changes in intraocular lens surface roughness during cataract surgery assessed by atomic force microscopy

“…Hypothetically, an ideal biocompatible IOL material [16][17][18][19] should prevent the migration and proliferation of LECs, and, in combination with IOL edge design, may reduce the incidence of PCO. 5 The biocompatibility of IOLs in terms of the inflammatory response and LEC reaction has been evaluated in many studies. 6,16,17,20 The degrees of cell adhesion and migration vary depending on the IOL's material properties.…”

“…This technology combines the capabilities of traditional ultramicroscopy with the ability to nondestructively analyze surface properties with nanometer resolution. 5,24,25 Advantages of AFM are the acquisition of 3-D images of the surface topography of solid interfaces, direct quantitative height information from the images obtained, and analysis of samples under near-use conditions. 5,13,25,26 Lombardo et al 5 found statistically significant differences in the surface roughness between various IOL materials.…”

“…The results are comparable to the mean range in published data. 5 Differences in IOL surface roughness are supposed to be dependent on the lens fabrication processes, 5,27,28 and it is speculated 5 that surface topography of the IOL optic varies by manufacturer depending on the manufacturing process used. This would include surface refinement of the IOL by barrel finishing or from a polished tool surface that was in contact during noncutting profiling with the IOL surface.…”

“…1 However, postoperative posterior capsule opacification (PCO) remains a major cause of visual impairment, [2][3][4] with lens epithelial cell (LEC) migration and adhesion being major factors in its development. 5 Several studies show this process is modulated by the design, biomaterial, and surface properties of an IOL. For example, a sharp posterior IOL edge is considered a major factor in preventing PCO.…”

“…13 Furthermore, acrylic and silicone IOLs were found to have smoother surfaces than PMMA IOLs. 5 In addition, differences in the topography of IOL biomaterials with identical copolymer constituents but different dioptric powers have been detected. 14 Recently, Erie et al 15 observed surface abnormalities in acrylic IOLs after they were folded using a folding insertion technique.…”