Generating scanning spot locations for laser eye surgery

A method of generating a treatment table for ablating tissue using a scanning laser beam for generating scanning spots over a treatment region larger in area than the scanning spots, the method comprising:

• providing a target function representing a desired lens profile for ablating the tissue by scanning spots of the laser beam on the tissue;
• providing a basis function representing a treatment profile produced by scanning with overlapping scanning spots of the laser beam to be centered at a plurality of locations on the tissue in a treatment pattern;
• and
• fitting the target function with the basis function to obtain a treatment table including scanning spot locations and characteristics for the overlapping scanning spots of the laser beam;
• wherein fitting the target function with the basis function includes fitting at N discrete evaluation points.

A method of generating a treatment table for ablating tissue using a scanning laser beam for generating scanning spots over a treatment region larger in area than the scanning spots, the method comprising:

• providing a lens function representing a desired lens profile for ablating the tissue by scanning spots of the laser beam on the tissue to achieve a desired removal of the tissue by ablating the tissue according to the desired lens profile represented by the target function;
• providing a user-specified basis function representing a treatment profile produced by the overlapping scanning spots along a treatment path, the user-specified basis function representing a section oriented across the treatment path;
• and
• fitting the lens function with the user-specified basis function to obtain a treatment table including scanning spot locations and characteristics for the overlapping scanning spots of the laser beam, such that an ablation employing the user-specified basis function according to the scanning spot locations and characteristics of the treatment table will substantially achieve the desired removal of the tissue as represented by the target function.

A method of generating a treatment table for ablating tissue using a scanning laser beam for generating scanning spots over a treatment region larger in area than the scanning spots, the method comprising:

• providing a lens function representing a desired lens profile for ablating the tissue by scanning spots of the laser beam on the tissue;
• providing a basis function representing a treatment profile produced by the overlapping scanning spots along a treatment path, the basis function representing a section oriented across the treatment path;
• and
• fitting the lens function with the basis function to obtain a treatment table including scanning spot locations and characteristics for the overlapping scanning spots of the laser beam;
• wherein the scanning spots are generally circular and have a generally uniform energy profile, and the basis function includes M discrete basis functions representing M overlapping scanning spots.

A method of generating a treatment table for ablating tissue using a scanning laser beam for generating scanning spots over a treatment region larger in area tan the scanning spots, the method comprising:

• providing a target function representing a desired lens profile for ablating the tissue by scanning spots of the laser beam on the tissue;
• providing a basis function representing a treatment profile produced by scanning with overlapping scanning spots of the laser beam to be centered at a plurality of locations on the tissue in a treatment pattern;
• and
• fitting the target function with the basis function to obtain a treatment table including scanning spot locations and characteristics for the overlapping scanning spots of the laser beam;
• wherein fitting the target function and the basis function comprises evaluating closeness of the fit and repeating the fitting step if the closeness does not fall within a target closeness.

A method of generating a treatment table for ablating tissue using a scanning laser beam for generating scanning spots over a treatment region larger in area than to scanning spots, the method comprising:

• providing a target function representing a desired lens profile for ablating the tissue by scanning spots of the laser beam on the tissue;
• providing a basis function representing a treatment profile produced by scanning with overlapping scanning spots of the laser beam to be centered at a plurality of locations on the tissue in a treatment pattern;
• fitting the target function with the basis function to obtain a treatment table including scanning spot locations and characteristics for the overlapping scanning spots of the laser beam;
• and
• randomizing the scanning spot locations of the treatment table to produce a random scanning order.

A method of generating a treatment table for ablating tissue using a scanning laser beam for generating scanning spots over a treatment region larger in area than the scanning spots, the method comprising:

• providing a target function representing a desired lens profile for ablating the tissue by scanning spots of the laser beam on the tissue;
• providing a basis function representing a treatment profile produced by scanning with overlapping scanning spots of the laser beam to be centered at a plurality of locations on the tissue in a treatment pattern;
• fitting the target function with the basis function to obtain a treatment table including scanning spot locations and characteristics for the overlapping scanning spots of the laser beam;
• and
• refitting the target function with the basis function by varying the size of at least one of the scanning spots to iterate for a best fit.

A system for ablating tissue, the system comprising

• a laser for generating a laser beam;
• a delivery device for delivering the laser beam to a tissue;
• a controller configured to control the laser and the delivery device;
• and
• a memory, coupled to the controller, comprising a computer-readable medium having a computer-readable program embodied therein for directing operation of the system, the computer-readable program including a first set of instructions for generating a treatment table including scanning spot locations and characteristics for ablating the tissue over a treatment region larger in area than the spot size of the laser beam to achieve a desired lens profile for ablating the tissue using scanning spots of the laser beam which are centered at a plurality of scanning spot locations on the tissue, a second set of instructions for controlling the laser to generate the laser beam, and a third set of instructions for controlling the delivery device to deliver the laser beam to the tissue according to the treatment table;
• wherein the first set of instructions of the computer-readable program includes:
• a first subset of instructions for providing a target function representing the desired lens profile for ablating the tissue by scanning spots of the laser beam on the tissue to achieve a desired removal of the tissue by ablating the tissue according to the desired lens profile represented by the target function;
• a second subset of instructions for providing a user-specified basis function representing a treatment profile produced by scanning with overlapping scanning spots of the laser beam to be centered at a plurality of scanning spot locations on the tissue in a user-specified treatment pattern;
• and
• a third subset of instructions for fitting the target function with the user-specified basis function to obtain the treatment table including the scanning spot locations and characteristics for the overlapping scanning spots of the laser beam, such that an ablation employing the user-specified basis function according to the scanning spot locations and characteristics of the treatment table will substantially achieve the desired removal of the tissue as represented by the target function.