Surgical apparatus for modifying the curvature of the cornea of ​​the eye

摘要

PCT No. PCT/FR86/00026 Sec. 371 Date Sep. 25, 1986 Sec. 102(e) Date Sep. 25, 1986 PCT Filed Jan. 30, 1986 PCT Pub. No. WO86/04500 PCT Pub. Date Aug. 4, 1986.A surgical apparatus for partially modifying the curvature of the cornea of an eye while the eye is within the patient is disclosed. The device is able to ablate a zone of corneal material in the form of a lenticular lamina. The thickness of the lamina at any particular point on the cornea surface varies as a function of the radial distance between that point and the central optical axis of the eye. The surgical apparatus comprises: a source of light (31) capable of emitting a beam of light (4) having a wavelength which is about 200 nanometers; an optical system (32) for directing and focusing the beam of light onto the desired zone of the cornea in order to ablate a lamina of material of the desired dimensions; and, a series of diaphragms and screens for obscuring varying portions of the zone of the cornea undergoing ablation in order to effect differential irradiation of the corneal surface. The longer the light beam (4) is allowed to impinge a particular portion of the cornea, the more corneal material removed from that spot and the greater the thickness of the lamina ( 2 and 16), and vice versa.