METHOD FOR CONTROLLING AN EYE SURGICAL LASER, COMPUTER PROGRAM PRODUCT, AND TREATMENT APPARATUS

Abstract

A method for controlling an eye surgical laser is disclosed for the separation of a volume body with a predefined posterior interface and a predefined anterior interface. The method includes controlling the laser by means of a control device such that it emits pulsed laser pulses into the cornea. Predefined posterior and anterior interfaces are generated by means of an interaction of the individual laser pulses with the cornea by the generation of cavitation bubbles along a rotation path. A respective interface is divided at least into an inner annulus and an outer annulus, and the cavitation bubbles are generated along the rotation path from an inner boundary of the outer annulus to an outer boundary of the outer annulus. Also disclosed in relation to the method are a computer program, a computer-readable medium and a treatment apparatus.

Claims

1. A method for controlling an eye surgical laser for the separation of a volume body with a predefined posterior interface and a predefined anterior interface from a human or animal cornea, comprising: controlling the laser by means of a control device such that is emits pulsed laser pulses in a shot sequence into the cornea, wherein the predefined posterior and anterior interfaces are generated by means of an interaction of the individual laser pulses with the cornea by the generation of a plurality of cavitation bubbles along a respective rotation path, wherein a respective interface is divided at least into an inner annulus and an outer annulus, and wherein the cavitation bubbles are generated along the rotation path from an inner boundary of the outer annulus, which faces an outer boundary of the inner annulus, to an outer boundary of the outer annulus, wherein the outer annulus encompasses the inner annulus.

2. The method according to claim 1, wherein cavitation bubbles are not generated in the inner annulus.

3. The method according to claim 1, wherein an inner boundary of the inner annulus is selected with a radius equal to zero.

4. The method according to claim 1, wherein a respective distance between adjacent cavitation bubbles is increased in the inner annulus with respect to a respective distance between adjacent cavitation bubbles in the outer annulus and/or a respective distance between adjacent rotation path parts of the rotation path is increased in the inner annulus with respect to a respective distance between adjacent rotation path parts of the rotation path in the outer annulus.

5. The method according to claim 1, wherein a repetition rate for emitting the laser pulses is changed for increasing the distance and/or a rotational speed of a deflection device for the laser of the treatment apparatus is changed for increasing the distance.

6. The method according to claim 1, wherein an inner boundary of the inner annulus is selected with a radius greater than zero.

7. The method according to claim 1, wherein the cavitation bubbles are generated in the inner annulus from the outer boundary of the inner annulus to an inner boundary of the inner annulus, and temporally thereafter, the cavitation bubbles are generated from the inner boundary of the inner annulus to the outer boundary of the inner annulus.

8. The method according to claim 5, wherein temporally after generating the cavitation bubbles from the inner boundary of the inner annulus to the outer boundary of the inner annulus, the cavitation bubbles are generated from the inner boundary of the outer annulus to the outer boundary of the outer annulus.

9. The method according to claim 1, wherein the cavitation bubbles are generated in the inner annulus from the outer boundary of the inner annulus to an inner boundary of the inner annulus, and temporally thereafter, the cavitation bubbles are generated from the inner boundary of the outer annulus to the outer boundary of the outer annulus.

10. The method according to claim 1, wherein in a first temporal step, the cavitation bubbles are generated from the inner boundary of the outer annulus to the outer boundary of the outer annulus, and temporally subsequently, the cavitation bubbles are generated from an inner boundary of the inner annulus to the outer boundary of the inner annulus.

11. The method according to claim 1, wherein the respective interfaces are divided at least into an additional middle annulus.

12. The method according to claim 1, wherein the control of the laser is effected such that topographic and/or pachymetric and/or morphologic data of the cornea is taken into account.

13. The method according to claim 1, wherein the control of the laser is effected such that the laser emits laser pulses in a wavelength range between 300 nm and 1400 nm, at a respective pulse duration between 1 fs and 1 ns, and a repetition frequency of greater than 10 kHz.

14. A treatment apparatus with at least one surgical laser for the separation of a volume body with predefined interfaces of a human or animal eye and with at least one control device, which is formed for controlling the laser according to claim 1.

15. The treatment apparatus according to claim 14, wherein the control device comprises at least one storage device for at least temporary storage of at least one control dataset, wherein the control dataset or datasets include control data for positioning and/or for focusing individual laser pulses in the cornea; and includes at least one beam device for beam guidance and/or beam shaping and/or beam deflection and/or beam focusing of a laser beam of the laser.

16. A computer program including commands, which cause a treatment apparatus with at least one surgical laser for the separation of a volume body with predefined interfaces of a human or animal eye and with at least one control device formed for controlling the laser to execute the method steps according to claim 1.

17. A computer-readable medium, on which the computer program according to claim 16 is stored.

18. A method for performing a surgical procedure on a human or animal cornea for the separation of a volume body from the cornea, wherein the interfaces are generated by means of an interaction of the individual laser pulses with the cornea by the generation of a plurality of cavitation bubbles along a respective rotation path, wherein a respective interface is divided at least into an inner annulus and an outer annulus, and wherein the cavitation bubbles are generated along the rotation path from an inner boundary of the outer annulus, which faces an outer boundary of the inner annulus, to an outer boundary of the outer annulus, wherein the outer annulus encompasses the inner annulus.

19. The method for performing a surgical procedure according to claim 18, wherein cavitation bubbles are not generated in the inner annulus.

20. The method for performing a surgical procedure according to claim 18, wherein an inner boundary of the inner annulus is selected with a radius equal to zero.

21. The method for performing a surgical procedure according to claim 18, wherein a respective distance between adjacent cavitation bubbles is increased in the inner annulus with respect to a respective distance between adjacent cavitation bubbles in the outer annulus and/or a respective distance between adjacent rotation path parts of the rotation path is increased in the inner annulus with respect to a respective distance between adjacent rotation path parts of the rotation path in the outer annulus.

22. The method for performing a surgical procedure according to claim 18, wherein a repetition rate for emitting the laser pulses is changed for increasing the distance and/or a rotational speed of a deflection device for the laser of the treatment apparatus is changed for increasing the distance.

23. The method for performing a surgical procedure according to claim 18, wherein an inner boundary of the inner annulus is selected with a radius greater than zero.

24. The method for performing a surgical procedure according to claim 18, wherein the cavitation bubbles are generated in the inner annulus from the outer boundary of the inner annulus to an inner boundary of the inner annulus, and temporally thereafter, the cavitation bubbles are generated from the inner boundary of the inner annulus to the outer boundary of the inner annulus.

25. The method for performing a surgical procedure according to claim 24, wherein temporally after generating the cavitation bubbles from the inner boundary of the inner annulus to the outer boundary of the inner annulus, the cavitation bubbles are generated from the inner boundary of the outer annulus to the outer boundary of the outer annulus.

26. The method for performing a surgical procedure according to claim 18, wherein the cavitation bubbles are generated in the inner annulus from the outer boundary of the inner annulus to an inner boundary of the inner annulus, and temporally thereafter, the cavitation bubbles are generated from the inner boundary of the outer annulus to the outer boundary of the outer annulus.

27. The method for performing a surgical procedure according to claim 18, wherein in a first temporal step, the cavitation bubbles are generated from the inner boundary of the outer annulus to the outer boundary of the outer annulus, and temporally subsequently, the cavitation bubbles are generated from an inner boundary of the inner annulus to the outer boundary of the inner annulus.

28. The method for performing a surgical procedure according to claim 18, wherein the respective interfaces (14, 16) are divided at least into an additional middle annulus.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0033] FIG. 1 is a schematic block diagram of an embodiment of a treatment apparatus.

[0034] FIG. 2 is a schematic top view to an eye.

[0035] FIG. 3 is a further schematic top view to an eye.

[0036] FIG. 4 is a still further schematic top view to an eye.

[0037] In the figures, identical or functionally identical elements are provided with the same reference characters.

[0038] FIG. 1 shows a schematic representation of a treatment apparatus 10 with an eye surgical laser 18 for the separation of a predefined corneal volume or volume body 12 with for example predefined interfaces 14, 16 of a cornea 44 (FIG. 2) of a human or animal eye 40 for example by means of photodisruption. One recognizes that a control device 20 for the laser 18 is formed besides the laser 18, such that it emits pulsed laser pulses in a predefined pattern into the cornea 44 in the present embodiment, wherein the interfaces 14, 16 of the volume body 12 to be separated are generated by the predefined pattern by means of photodisruption. In the illustrated embodiment, the interfaces 14, 16 form a lenticular volume body 12, wherein the position of the volume body 12 is selected in this embodiment such that a pathological and/or unnaturally altered area within a stroma 36 of the cornea 44 or an area, in which visual disorders arise, is encompassed. Furthermore, it is apparent from FIG. 1 that the so-called Bowman's membrane 38 is formed between the stroma 36 and an epithelium.

[0039] Furthermore, one recognizes that the laser beam 24 generated by the laser 18 is deflected towards a surface 26 of the cornea by means of a beam deflection device 22, such as for example a scanner. The beam deflection device 22 is also controlled by the control device 20 to generate the mentioned predefined pattern in the cornea. The beam deflection device 22 can for example comprise two mirrors, which are formed for deflecting the impinging laser beam 24. In a neutral position, a so-called 0/0 position of the mirrors, an optical axis of the laser beam 24 is in particular formed.

[0040] The illustrated laser 18 is a photodisruptive laser, which is formed to emit laser pulses in a wavelength range between 300 nm and 1400 nm, preferably between 700 nm and 1200 nm, at a respective pulse duration between 1 fs and 1 ns, preferably between 10 fs and 10 ps, and a repetition frequency of greater than 10 kHz, preferably between 100 kHz and 100 MHz. Alternatively to the treatment apparatus 1 shown in FIG. 1, a method for ablative removal of the volume body 12 can also be used.

[0041] In addition, the control device 20 comprises a storage device (not illustrated) for at least temporary storage of at least one control dataset, wherein the control dataset or datasets include(s) control data for positioning and/or for focusing individual laser pulses in the cornea 13. The position data and/or focusing data of the individual laser pulses are generated based on a previously measured topography and/or pachymetry and/or the morphology of the cornea and the pathological and/or unnaturally altered area 32 for example to be removed within the stroma 36 of the eye.

[0042] FIG. 2 shows a schematic top view to the eye 40. Further, FIG. 2 shows the volume body 12. Furthermore, an incision 42 is shown, via which the volume body 12 can be removed from the cornea 44.

[0043] In the method for controlling the eye surgical laser 18 for the separation of the volume body 12 with the predefined posterior interface 14 and the predefined anterior interface 16 from the human or animal cornea 44, the control of the laser 18 by the control device 20 is effected such that the laser 18 emits laser pulses in a shot sequence into the cornea 44, wherein the interfaces 14, 16 are generated by means of an interaction of the individual laser pulses with the cornea 44, for example by means of photodisruption, by the generation of a plurality of cavitation bubbles along a respective rotation path 60, wherein a respective interface 14, 16 is divided at least into an inner annulus 46 and an outer annulus 48, and wherein the cavitation bubbles are generated along the rotation path 60 from an inner boundary 50 of the outer annulus 48, which faces an outer boundary 52 of the inner annulus 46, to an outer boundary 54 of the outer annulus 48.

[0044] In the present embodiment, the outer boundary 52 of the inner annulus 46 corresponds to the inner boundary 50 of the outer annulus 48.

[0045] Further, the rotation path 60 is presently spirally formed and a movement direction arrow 58 of the rotation path 60 from the inside to the outside is shown.

[0046] In particular, the figures are only schematic and not to scale. The drawings only serve for exemplifying the method. In particular, the inner annulus 46 is formed substantially smaller with respect to the outer annulus 48 than illustrated in the figures.

[0047] In a form of configuration, it can be provided that cavitation bubbles are not generated in the inner annulus 48. Herein, it can for example be provided that the inner boundary 56 of the inner annulus 46 is selected with a radius equal to zero. In other words, the inner radius, as presently shown, can be selected such that the inner annulus 46 is formed as a disk. In particular, the radius of the outer boundary 52 of the inner annulus 46 can be selected correspondingly small such that the cavitation bubbles are only generated in the outer annulus 48, and a reliable removal of the volume body 12 can nevertheless be realized.

[0048] Further, it can be provided that a respective distance between adjacent cavitation bubbles is increased in the inner annulus 46 with respect to a respective distance between adjacent cavitation bubbles in the outer annulus 48 and/or a respective distance between adjacent rotation path parts of the rotation path 60 is increased in the inner annulus 46 with respect to a respective distance between adjacent rotation path parts of the rotation path 60 in the outer annulus 48. Thus, the distances of the cavitation bubbles in the inner annulus 46 are in particular selected larger than in the outer annulus 48. Herein, it can for example be provided that a repetition rate for emitting the laser pulses is changed for increasing the distance and/or a rotational speed of the beam deflection device 22 for the laser 18 of the treatment apparatus 10 is changed for increasing the distance.

[0049] FIG. 3 shows a further schematic top view to an eye 40. In the present embodiment, it is in particular shown that the inner boundary 56 of the inner annulus 46 is selected with a radius greater than zero. Presently, it is in particular to be noted that the illustrated sizes are purely schematically represented. The inner radius of the inner annulus 46 is in particular selected very small such that a reliable removal of the volume body 12 is also realized for example without generating cavitation bubbles further inwards. In other words, the present representation purely schematically serves for explaining the idea of the embodiment according to the invention.

[0050] Alternatively thereto, it can in particular be provided that the cavitation bubbles are generated in the inner annulus 46 from the outer boundary 52 of the inner annulus 46 to the inner boundary 56 of the inner annulus 46, and temporally thereafter, the cavitation bubbles are generated from the inner boundary 56 of the inner annulus 46 to the outer boundary 52 of the inner annulus 46. Thus, the cavitation bubbles are generated twice in the inner annulus 46. First, the cavitation bubbles are generated from the outside to the inside and then from the inside to the outside in the inner annulus 46. Herein, it can then for example be provided subsequently thereto that temporally after generating the cavitation bubbles from the inner boundary 56 of the inner annulus 46 to the outer boundary 52 of the inner annulus 46, the cavitation bubbles are generated from the inner boundary 50 of the outer annulus 48 to the outer boundary 54 of the outer annulus 48.

[0051] Still alternatively, it can be provided that the cavitation bubbles are generated in the inner annulus 46 from the outer boundary 52 of the inner annulus 46 to the inner boundary 56 of the inner annulus 46, and temporally thereafter, the cavitation bubbles are generated from the inner boundary 50 of the outer annulus 48 to the outer boundary 54 of the outer annulus 48.

[0052] Further, it can be provided in an embodiment that the cavitation bubbles are generated from the inner boundary 50 of the outer annulus 48 to the outer boundary 54 of the outer annulus 48 in a first time step, and temporally subsequently, the cavitation bubbles are generated from the inner boundary 56 of the inner annulus 46 to the outer boundary 52 of the inner annulus 46.

[0053] FIG. 4 shows a still further schematic top view to an eye 40. In this embodiment, it can be provided that the respective interfaces 14, 16 are divided at least into one further middle annulus 62. The additional middle annulus 62 is to be purely exemplarily understood. The volume body 12 can also be divided into more than three annuli.

[0054] In this embodiment, it is shown that the middle annulus 62 is located between the inner annulus 46 and the outer annulus 48. Then, it can for example be provided that the cavitation bubbles are first generated from the inside to the outside in the outer annulus 48. Subsequently thereto, the cavitation bubbles are generated in the middle annulus 62 from the inside to the outside. Subsequently thereto, the cavitation bubbles are generated in the inner annulus 46 for example also from the inside to the outside.

[0055] Thus, it is in particular provided that at least in the outer annulus 48, the cavitation bubbles are always generated from the inner boundary 50 of the outer annulus 48 to the outer boundary 54 of the outer annulus 50. Thus, so-called opaque bubble layers can be prevented.