| 摘要 |
<p>The present invention provides a new approach to reshaping of the cornea, e.g., for refraction change, using multiple, displaced planar cuts and a custom shaping template. Large refractive change and/or substantial tissue removal can be obtained by a two-cut approach to reshaping of the cornea to a desired shape using a template or applanator. The process begins with a planar template being applied to the cornea. The template includes one or more moveable sections or cams positioned to provide an overall flat contact surface with the cornea. Then, a first cut is made by a water microjet producing a hinged flap. The first cut is parallel to but displaced from the anterior cornea surface in contact with the template. Then the template cam or cams are repositioned to change the shape of the cornea surface in situ in preparation for the second cut. The hinged flap is not moved; it remains in contact with the stromal bed. The second cut is along the same path as the first cut. However, since the cornea has been reshaped, the second cut defines a separate cut line in the cornea. As a result of the first and second cuts, a body of internal tissue defined by the relative paths of the first and second cuts through the corneal tissue can be removed from the cornea to thereby shape the cornea and provide refractive correction. This enables a large range of accurate refractive correction and/or therapeutic tissue removal by directly controlling the geometry of the volume of tissue removed from the interior of the cornea.</p> |
