A series of pits varying in depth and size appeared on the anterior surface of hydrogel intraocular lenses (IOLs) soon after they were implanted. In all cases, the pits increased in size but not in number during a 1 year follow-up. The origin of the pit defects is unknown and does not seem related to inflammatory or lens epithelial cell activity. Hydration of the IOL could be a cause even if a manufacturing defect were present. This IOL surface alteration did not seem to impair visual function or cause visual disturbances.