Patent ID: 7992569

Claim:
A refractive ophthalmic treatment method comprising: receiving pre-operative data concerning a cornea on which the treatment will be performed; subtracting a programmed optical zone correction from corneal measurements provided in the pre-operative data to provide a predicted location of a post-operative optical zone edge; calculating a predicted curvature of the cornea at the edge of the optical zone, near the edge of the optical zone, or combinations thereof after application of the programmed optical zone correction; calculating a customized transition zone pattern which addresses curvature discontinuity by eliminating its occurrence in the programmed optical zone, near the programmed optical zone, or combinations thereof, wherein calculation of the customized transition zone pattern is based, at least in part, on the pre-operative data received and the predicted curvature of the cornea, and wherein calculation of the customized transition zone pattern involves use of a curve fitting algorithm to generate a transition zone with a continuous second derivative along a profile of the cornea outwardly from the programmed optical zone correction; applying the customized transition zone pattern to a designed ablation zone pattern to provide an updated ablation zone pattern, wherein corrective properties of the customized transition zone pattern are included in the updated ablation zone pattern to facilitate an increased functional optical zone; and performing an ablation on the cornea based on the updated ablation zone pattern.