Abstract: The optical portion of a prosthetic cornea fabricated from a relatively inert, transparent, substantially rigid material is shaped to provide a correction factor consistent with the requirements of a selected patient. During implantation a receptacle for receiving the optical portion of the prosthetic cornea is formed by excising a portion of the living cornea. A stromal pocket is formed into the posterior one-third of the stroma of the living cornea receiver and an attachment portion of the prosthetic cornea is secured within the stromal pocket. The attachment portion extends outwardly from the optical portion, and apertures through the attachment portion serve to promote the transfer of nutrients and other fluids and gases as well as allowing normal fibrous tissue growth which aids in anchoring the prosthetic cornea in place over the long term. The apertures may optionally also be employed to facilitate the use of sutures during the implantation process.

Abstract: A contact lens whose posterior surface has three zones, a central, an intermediate and a peripheral. The anterior surface of the lens also has a central zone corresponding to the posterior central zone. The central zones of these surfaces form the optical zone of the lens. The posterior intermediate zone of the lens is aspheric with its radius of curvature increasing continuously from the central to the peripheral zones to cause the cornea to assume a more optimal shape. The chord diameter of the posterior central zone is equal to or less than the measured maximum radius of curvature of the central zone of the cornea and preferably larger than the largest measured diameter of the pupil of the eye of the patient.