CK was originally designed as a surgical procedure used to correct small amounts farsightedness by steepening the corneal curvature using radio-frequency. A concentric ring of 8-24 equally spaced treatment spots are placed in the mid- peripheral cornea to increase the curvature of the cornea. Not long after, the idea came along to use this same treatment to eliminate the need for reading glasses. CK is an effective procedure to temporarily reduce or eliminate reading glasses, with regression occurring approximately 1 year after the initial treatment, requiring a “touchup” in most cases.