MODEL RELEASED. Eye surgery (image 1 of 6). Face of an elderly woman prepared for eye surgery. She has a transparent sticky surgical covering over her face and her eye is held open by retractors. She has a cataract, a cloudy lens in her eye, that must be replaced with a lens implant (prosthesis). Her diseased cornea will also be replaced by keratoplasty, the graft or transplantation of a cornea from a donor. The cornea is a transparent membrane over the front of the eye that focuses entering light. The light is then finely focused deeper in the eye by the lens. For a sequence of this surgery see images M570/116-121.