Thermal techniques for reshaping the cornea

Abstract

The shape of the cornea of the eye can be modified to correct permanently for near-sightedness or far-sightedness. Heat energy can be delivered to the cornea for this purpose in order to elevate the collagen in mid-cornea to its shrinkage temperature of about 60 °C. When a suitable pattern of shrinkage is created in the peripheral cornea, the central cornea may steepen or flatten in response, and this change in curvature may serve as a refractive correction. This paper reviews the following methods for heating the cornea for this purpose: conduction, radio-frequency, laser, and microwave.