What is the X in X-mas?
radial keratotomy n.
Surgical modification of corneal curvature to correct myopia by making symmetrical incisions into but not through the cornea.
surgical procedure to correct myopia (nearsightedness) by reducing the radius of curvature of the cornea and astigmatism (asymmetrical curvature of the cornea). A series of 4 to 8 equally spaced deep cuts are made in the peripheral cornea, leaving the central cornea above the pupil clear. Intraocular pressure then pushes the weakened central cornea outward, flattening it and modifying its refractive power. Wound contraction during healing also affects corneal curvature by exerting radial tension on the uncut area.