System and method for providing the shaped structural weakening of the human lens with a laser
A system and method for increasing the amplitude of accommodation and/or changing the refractive power of lens material of a natural crystalline lens is provided. Generally, there is provided methods and systems for delivering a laser beam to a lens of an eye in a plurality of sectional patterns results in the shaped structural weakening of the lens. There is also provided a method and system for determining adjustments to refractive errors in the lens of an eye relating to the treatment of presbyopia. The change to refractive error can be a predicted error or an actual error that has been determined.
1. A system for delivering a laser beam to a lens of an eye in a plurality of sectional patterns comprising:
a. a laser generating a beam of light;
b. optics for receiving the beam of light and directing the beam of light toward the lens of the eye;
c. a control system in communication with the optics, wherein the control system generates and sends signals to the optics directing the laser so that:
i. a first predetermined sectional pattern is formed on a first portion of the lens of the eye; and
ii. a second predetermined sectional pattern is formed on a second portion of the lens of the eye; and,
iii. the first predetermined sectional pattern having a first plurality of lens cuts generally parallel to an optical axis of the lens of the eye, and the second predetermined sectional pattern having a second plurality of lens cuts generally following the curvature of an anterior surface of the lens of the eye, such that the combination and placement of the first and second predetermined sectional patterns is selected to result in an altered lens of the eye having a weaker structure than a structure of the lens of the eye prior to formation of the first predetermined sectional pattern and the second predetermined sectional pattern.
2. The system of claim 1 wherein the combination and placement of the first and second predetermined sectional patterns is selected to achieve at least in part improved accommodative amplitude of the altered lens of the eye when compared with an accommodative amplitude of the lens of the eye prior to the formation of the first predetermined sectional pattern and the second predetermined sectional pattern.
3. The system of claim 1 wherein the combination and placement of the first and second predetermined sectional patterns is selected to achieve at least in part improved refractive error of the altered lens of the eye when compared with a refractive error of the lens of the eye prior to the formation of the first predetermined sectional pattern and the second predetermined sectional pattern.
4. The system of claim 1 wherein the combination and placement of the first and second predetermined sectional patterns is selected to achieve at least in part improved accommodative amplitude and improved refractive error of the altered lens when compared with an accommodative amplitude and a refractive error of the lens of the eye prior to formation of the first predetermined sectional pattern and the second predetermined sectional pattern.
5. The system of claim 1 wherein the first plurality of lens cuts are patterned along a first direction and are positioned in more central areas of the lens and the second plurality of lens cuts are patterned along a second direction that is perpendicular to the first direction and are positioned in a more peripheral area of the lens.
6. The system of claim 1 wherein the first predetermined sectional pattern applied to the lens primarily results in a flexibility of the altered lens that is greater than a flexibility of the lens prior to formation of the first predetermined sectional pattern and the second predetermined sectional pattern and the second predetermined sectional pattern applied to the lens primarily results in shaping the lens so as to form the altered lens.
7. The system of claim 6 , wherein the second predetermined sectional pattern is directed primarily toward preserving lens shape.
8. The system of claim 6 , wherein the second predetermined sectional pattern is directed primarily toward changing lens shape.