Methods and systems for laser ophthalmic surgery that provide for iris exposures below a predetermined exposure limit

1. A laser surgical method for performing a corneal incision in an eye of a patient while maintaining iris exposure below a predetermined exposure limit, the method comprising:

generating a simulated initial treatment scan pattern of a pulsed laser treatment beam corresponding to a predetermined corneal incision in the eye;

calculating an initial exposure level, which is an amount of laser energy per unit area of the pulsed laser treatment beam on an iris tissue of the eye caused by the initial treatment scan pattern;

determining whether the initial exposure level satisfies a predetermined safe exposure condition which is below an exposure that causes a minimal visible lesion in the iris tissue;

generating a simulated revised treatment scan pattern of the pulsed laser treatment beam for incising the corneal tissue which is different from the initial treatment scan pattern and which comprises one or more treatment scan modifying elements when the initial indication of exposure level fails to satisfy the predetermined safe exposure condition, wherein the one or more treatment scan modifying elements cause a calculated revised exposure level, which is an amount of laser energy per unit area of the pulsed laser treatment beam on the iris tissue caused by the revised treatment scan pattern, to satisfy the predetermined safe exposure condition,

wherein the one or more treatment modifying elements comprises: (1) an extension of a scan path of the scan pattern so that a portion of each turnaround of the scan path occurs beyond an incision boundary, the extension of the scan path being greater than 50% of a turnaround distance of the scan path, or (2) an extension of the scan path of the scan pattern so that a portion of each turnaround of the scan path is gated and extends beyond the incision boundary, the extension of the scan path being greater than 50% of a turnaround distance of the scan path, or (3) a reoriented scan axis, wherein the reoriented axis is reoriented along an axis corresponding to a largest distance between opposing incision boundaries, or (4) a plurality of gated rows of a scan path inserted among active rows of the scan path in a fixed proportion, the fixed proportion being greater than or equal to one, and less than or equal to 10; and

scanning a focal zone of the pulsed laser treatment beam according to the revised treatment scan pattern, thereby performing the corneal incision.

2. The method of claim 1 , further comprising performing a capsulotomy on the eye with the laser treatment beam.

3. The method of claim 2 , wherein the corneal incision is an arcuate corneal incision, a sideport cataract incision, or a primary cataract incision.

4. The method of claim 1 , wherein the initial scan pattern includes a set of parameters defining an arcuate corneal incision, a sideport cataract incision, or a primary cataract incision.

5. The method of claim 4 , wherein the revised treatment scan pattern further includes a revised value for at least one of the set of parameters.

6. A laser surgical method for performing a corneal incision in an eye of a patient while maintaining iris exposure below a predetermined exposure limit, the method comprising:

generating a simulated initial treatment scan pattern of a pulsed laser treatment beam corresponding to a predetermined corneal incision in the eye;

calculating a first time period over which the initial treatment scan pattern is carried out to deliver a first amount of laser energy on an iris tissue of the eye;

determining whether the first time period is greater than a predetermined minimum time period to deliver the first amount of laser energy on the iris tissue;

generating a simulated revised treatment scan pattern of the pulsed laser treatment beam for incising the corneal tissue which is different from the initial treatment scan pattern and which comprises one or more treatment scan modifying elements when the first time period is not greater than the predetermined minimum time period, wherein the one or more treatment scan modifying elements cause a calculated second time period over which the revised treatment scan pattern is carried out to be greater than the predetermined minimum time period; and

scanning a focal zone of the pulsed laser treatment beam according to the revised treatment scan pattern, thereby performing the corneal incision.

7. The method of claim 6 , wherein the one or more treatment scan modifying elements comprises an extension of scan paths so that at least a portion of turnarounds occur beyond an incision boundary, the extension of the scan paths being greater than 50% of a turnaround distance, and wherein a region corresponding to the portion of the scan paths extending beyond the respective incision boundary is not incisionable by the pulsed laser treatment beam.

8. The method of claim 6 , wherein the one or more treatment scan modifying elements comprises an extension of the scan paths so that at least a portion of turnarounds are gated and extend beyond the incision boundary, the extension of the scan paths being greater than 50% of a turnaround distance.

9. The method of claim 6 , wherein the one or more treatment scan modifying elements comprises a reoriented scan axis, and wherein the reoriented axis is reoriented along an axis corresponding to a largest distance between opposing incision boundaries.

10. The method of claim 6 , wherein the one or more treatment scan modifying elements comprises a plurality of gated rows of a scan path inserted among active rows of the scan path in a fixed proportion, the fixed proportion being greater than or equal to one and less than or equal to 10.

11. The method of claim 6 , further comprising performing a capsulotomy on the eye with the laser treatment beam.

12. The method of claim 11 , wherein the corneal incision is an arcuate corneal incision, a sideport cataract incision, or a primary cataract incision.

13. The method of claim 6 , wherein the initial scan pattern includes a set of parameters defining an arcuate corneal incision, a sideport cataract incision, or a primary cataract incision.

14. The method of claim 13 , wherein the revised treatment scan pattern further includes a revised value for at least one of the set of parameters.

15. A laser surgical method for performing a corneal incision in an eye of a patient while maintaining iris exposure below a predetermined exposure limit, the method comprising:

receiving a parameter set from a user via a user interface device;

generating a simulated initial treatment scan pattern of the laser treatment beam for incising the corneal tissue based on the parameter set received via the user interface device;

calculating an initial exposure level, which is an amount of laser energy per unit area of the laser treatment beam on an iris tissue of the eye caused by the initial treatment scan pattern;

determining whether the initial exposure level satisfies a predetermined safe exposure condition which is below an exposure that causes a minimal visible lesion in the iris tissue;

receiving a revised parameter set from the user via the user interface device, the revised parameter set having at least one different parameter value than the initial parameter set,

wherein: (1) the parameter set defines an arcuate corneal incision, and the at least one different parameter value is selected from a group of values consisting of incision type, axis, optical zone, arc length, centering method, penetration type, depth units, uncut anterior, uncut posterior, and side cut angle, or (2) the parameter set defines a primary cataract incision, and the at least one different parameter value is selected from a group of values consisting of axis, limbus offset, width, length, uncut region, depth units, uncut anterior, uncut posterior, uncut central, length, plane depth, and side cut angle, or (3) the parameter set defines a sideport cataract incision, and the at least one different parameter value is selected from a group of values consisting of a number of incisions, an axis, a limbus offset, a width, an uncut type, an uncut units, an anterior uncut length, a posterior uncut length, and a side cut angle;

generating a simulated revised treatment scan pattern of the laser treatment beam for incising the corneal tissue which is different from the initial treatment scan pattern and which is based on the revised parameter set received via the user interface;

calculating a revised exposure level, which is an amount of laser energy per unit area of the laser treatment beam on the iris tissue caused by the revised treatment scan pattern;

determining whether the revised exposure level satisfies the predetermined safe exposure condition; and

scanning a focal zone of the pulsed laser treatment beam according to the revised treatment scan pattern if the revised exposure level satisfies the predetermined safe exposure condition, thereby performing the corneal incision.