High-order aberrations in pseudophakia with different intraocular lenses

PURPOSE: To compare high-order aberrations in patients who had cataract surgery and implantation of different types of intraocular lenses (IOLs). SETTING: Sir Charles Gairdner Hospital and Lions Eye Institute, University of Western Australia, Perth, Australia. METHODS: Fifty eyes of 48 patients were included in this study. The optical aberrations were measured with the Hartmann-Shack wavefront sensor (Zyoptix, Bausch & Lomb) before and after surgery using a 5.0 mm wavefront aperture diameter for all comparisons. The eyes were divided into 4 groups according to the type of IOL (material and curvature). A fifth group of 10 eyes of 6 elderly patients with normal crystalline lenses had the same examination. RESULTS: There was no statistical difference in high-order aberrations between the 2 acrylic IOL groups with different curvatures (P>.05) or between the silicone and poly(methyl methacrylate) (PMMA) IOL groups (P>.05). However, the measured high-order aberrations were significantly higher (3rd through 5th order) in the 2 acrylic IOL groups than in the PMMA and silicone IOL groups (P<.05). CONCLUSIONS: An increase in IOL high-order aberrations contributed to the decline in retinal image quality. An IOL modifies the entire aberration pattern of the eye. There was a statistically significant increase in aberrations in patients with an acrylic IOL compared to those with a silicone or PMMA IOL. The exact mechanism is uncertain. Further study is required to optimize IOL design.