Corneal topography-based target warping
View Patent ↗Systems and methods for treating a tissue of an eye with a laser beam include at least one processor that determines angles between a curved surface and a laser beam, controlling an ablative treatment in response to the angles. Angles between a surface of a cornea and a laser beam may be mapped over a treatment area. A mapped area may include an apex of a cornea displaced from a center of a pupil of an eye. Ablation properties may be determined locally in response to the incident angle of a laser beam with respect to a local slope of a tissue surface. The treatment area may be ablated using local ablation properties to form a desired surface shape.
1. A method of treating a cornea of a patient's eye with a laser beam, the method comprising:
mapping angles between a surface of the cornea and the laser beam over a treatment area;
determining ablation properties locally across the treatment area in response to the mapped angles;
formulating a treatment plan using the ablation properties by adjusting a first virtual ablation shape to form a second virtual ablation shape, the first virtual shape representing a depth of material to be removed from the treatment area to form a desired shape, the second virtual shape being formed from the first virtual shape in response to the mapped angles and;
ablating the treatment area according to the treatment plan to form the desired shape in the surface.
2. The method of claim 1 wherein the laser beam is substantially parallel to an optical axis of the eye.
3. The method of claim 1 wherein the mapped area includes an apex of the cornea and the apex of the cornea is displaced from a center of a pupil of the eye.
4. The method of claim 3 wherein the desired shape has a center, and the center of the desired shape is aligned with the center of the pupil of the eye.
5. The method of claim 1 wherein a depth of the second virtual shape is greater than a depth of the first virtual shape.
6. The method of claim 1 wherein a depth of the second virtual shape is less than a depth of the first virtual shape.
7. The method of claim 1 wherein the desired shape is based at least in part on a result of a measurement selected from the group consisting of an aberration measurement of the eye, a refractive measurement of the eye and a topography measurement of the eye.