Visx, Inc.

Amo Manufacturing Usa, LLC

Stephen J Koons

John Karl Shimmick

Richard A Hofer

Kingman Yee

George Caudle

Systems, methods and apparatus for performing selective ablation of a corneal surface of an eye to effect a desired corneal shape, particularly for correcting a hyperopic/astigmatic condition by laser sculpting the corneal surface to increase its curvature. In one aspect of the invention, a method includes the steps of directing a laser beam onto a corneal surface of an eye, and changing the corneal surface from an initial curvature having hyperopic and astigmatic optical properties to a subsequent curvature having correctively improved optical properties. Thus, the curvature of the anterior corneal surface is increased to correct hyperopia, while cylindrical volumetric sculpting of the corneal tissue is performed to correct the astigmatism. The hyperopic and astigmatic corrections are preferably performed by establishing an optical correction zone on the anterior corneal surface of the eye, and directing a laser beam through a variable aperture element designed to produce a rectangular ablation (i.e., cylindrical correction) on a portion of the optical correction zone. The laser beam is then displaced by selected amounts across the optical correction zone to produce a series of rectangular ablations on the correction zone that increases the curvature of the corneal surface to correct the hyperopic refractive error.

Systems and methods for corneal surface ablation to correct hyperopia

A trephine can separate a cornea into at least two portions by applanating and cutting a boundary around an area of the cornea. The trephine comprises a flat ring for applanating the cornea and a blade for cutting the applanated cornea. The blade extends radially inward and is rotatable around the ring. Such a trephine can cut substantially parallel to the flattened lamella and causes lamellar separation at the cut depth. A flap of cornea may be separated from the remaining corneal tissue along the lamella by teasing the portions apart, or by injecting fluid between the lamellae. An exposed surface of the separated cornea may then be ablated with a laser and the flap reattached to the remaining corneal tissue.

Trephine for lamellar keratectomy

A technique for laser sculpting a predetermined shape on an exposed corneal surface by ablating a sequence of consistently curved craters with individual pulses of a laser beam. An initial laser beam energy pattern is shaped by a laser beam shaping element to make a consistently curved laser beam energy pattern. The consistently curved laser beam ablates a consistently curved crater in the surface with a single pulse of the laser beam. A computer controls the position of the laser beam and scans the laser beam over the surface to sculpt the predetermined shape in an ablation zone on the exposed surface. A sequence of partially overlapping craters is distributed over the ablation zone. In some embodiments diffractive optics are used as a beam shaping element. In additional embodiments, the consistently curved crater is a uniformly curved spherical crater.

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Sunnyvale, CA, United States of America

Stephen J Koons