Design of Keratorefractive Surgical Procedures: Radial Keratotomy

By surgically incising a patient’s cornea, an ophthalmologist can reduce or eliminate the patient’s myopia (nearsightedness). Although one such keratorefractive produre, known as radial keratotomy, is a common practice among some ophthalmologists, there is presently no comprehensive or universally accepted method that a surgeon can use to determine how to perform the operation to exactly eliminate a patient’s refractive error. In this paper, a general methodology for designing radial keratotomy procedures that determines the optimal incision geometry on a patient-by-patient basis is presented. This approach is based on coupling a transversely isotropic finite element model of the human cornea to an optical model of the entire eye. The resulting incision geometry obtained from each design formulation not only eliminates the myopic error but yields the global minimum of the objective function.