Anesthetic eye drops are applied, and the surface cells of the cornea (the epithelium) are gently removed so the riboflavin eye drops can penetrate into the cornea. The riboflavin eye drops are applied and allowed to soak into the cornea. The cornea is then irradiated with ultra-violet light. The amount of time the riboflavin soaks into the eye and the amount of time the cornea is irradiated with ultra-violet light vary significantly depending on the ultraviolet light source used by the ophthalmologist. Advances in ultraviolet light sources have reduced total procedure time from one hour to as little as 12 minutes. At the completion of the procedure, a bandage contact lens is inserted, and the eye is patched overnight.