Peripheral visual field shifts after intraocular lens implantation

PURPOSE: To assess whether intraocular lens (IOL) implantation induces shifts in the peripheral visual field. SETTING: Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands. DESIGN: Ray-tracing study. METHODS: Nonsequential ray-tracing simulations were performed with phakic and pseudophakic versions of the same eye model to assess potential shifts in the visual field after IOL implantation. 2 different IOL designs were evaluated and for each design 5 different axial positions and 7 different intrinsic powers were tested. The relation between the physical position of the light source and the location where the retina was illuminated was determined for each eye model. Subsequently, these relations were used to calculate whether the visual field shifts in pseudophakic eyes. RESULTS: The pseudophakic visual field shift was below 1 degree for central vision in all evaluated models. For peripheral vision, the light rays in the pseudophakic eyes were refracted to a more central retinal location compared with phakic eyes, resulting in a central shift of the peripheral visual field. The magnitude of the shift depended on the IOL design and its axial position, but could be as high as 5.4 degrees towards central vision. CONCLUSIONS: IOL implantation tends to have little effect on the central visual field but can induce an over 5 degrees shift in the peripheral visual field. Such a shift can affect the perception of peripheral visual complaints.