Method for providing control data for an ophthalmic ablation laser of a treatment device

Abstract

The invention relates to a treatment device (10) and a method for providing control data for an ophthalmic ablation laser (12) of a treatment device (10). The method comprises determining (S10) a planned path (26) of an opening incision (24) in a cornea (16), which is defined as the line connecting an existing incision (14) within the cornea (16) to an outer surface of the cornea (16), wherein the opening incision (24) was inadequately created in a previously performed treatment; and generating (S12) an ablation planning pattern by which a planned positioning of laser pulses along the determined path (26) of the opening incision (24) from the surface of the cornea (16) to the existing incision (14) within the cornea (16) is provided. and the provision (S14) of the control data for the ophthalmic ablation laser (12), which includes the ablation planning pattern.

Description

[0001] The invention relates to a method for providing control data for an ophthalmic ablation laser of a treatment device. Furthermore, the invention relates to a control device configured to carry out the method, a treatment device having such a control device, a computer program comprising commands that cause the treatment device to carry out the method, and a computer-readable medium on which the computer program is stored.

[0002] Treatment devices and methods for controlling ophthalmic lasers to correct optical refractive errors and / or pathologically or abnormally altered areas of the cornea are known in the prior art. For example, pulsed lasers and a beam focusing device can be configured such that laser pulses in a focus located within the organic tissue cause photodisruption and / or ablation, in particular plasma-assisted ablation, to remove tissue, in particular a tissue lenticle, from the cornea.

[0003] In such procedures, an opening or marginal incision is typically created using a femtosecond laser, which typically extends from an incision within the cornea to a surface of the cornea. This opening incision can be used, for example, to create a corneal flap or to remove a lenticule created within the cornea, which is then also referred to as an incision for lenticule extraction.

[0004] However, it may happen that this opening incision was created poorly, meaning that it is not cut all the way to the surface, for example, because a vacuum tear of an eye fixation device occurred before the opening incision was completed, or a user is no longer able to see the opening incision because the bubbles have already diffused. It may also happen that sufficient separation is not achieved in the corneal tissue surrounding the opening incision.

[0005] Therefore, it is an object of the invention to provide control data for the improved generation of an opening cut.

[0006] This object is achieved by the independent patent claims. Advantageous developments of the invention are disclosed in the dependent patent claims, the following description, and the figures.

[0007] The invention is based on the idea that a contour of the opening incision is traced with an ablation laser, which removes corneal tissue to facilitate entry or make the incision more visible.

[0008] One aspect of the invention relates to a method for providing control data for an ophthalmic ablation laser of a treatment device, wherein the method comprises the following steps, which are carried out by a control device. A control device is understood to be a device or device component, in particular a computer or processor, which can carry out the following steps automatically or semi-automatically.

[0009] A planned path of an opening incision in a cornea is determined, which is defined as a connection from an existing incision within the cornea to an outer surface of the cornea, wherein the opening incision was created inadequately in a previously performed treatment. Furthermore, an ablation planning pattern is generated, which provides planned positioning of laser pulses along the determined path of the opening incision from the surface of the cornea to the existing incision within the cornea, and the control data for the ophthalmic ablation laser, which comprises the ablation planning pattern, is provided.

[0010] In other words, the planned course of the inadequately created opening incision can first be determined. An opening incision here refers to incisions that were made within the cornea during a previous treatment with a femtosecond laser using photodisruption or photoablation, and that lead from an incision within the cornea to the outer surface of the cornea. These opening incisions can be made, for example, when creating a foldable corneal lamella or during an incision that leads from a created lenticule within the cornea to the outer surface of the cornea. In particular, the opening incision runs from the incision within the cornea towards the surface, so that if the opening incision is inadequately created, there can be no connection to the surface of the cornea.

[0011] To determine the planned path, measurements of the eye or cornea can be taken, for example, using a camera or optical coherence tomography, from which at least a portion of the defective or incompletely created incision can be identified. Alternatively or additionally, control data from the previous treatment may be available, from which the planned path of the opening incision can be determined.

[0012] An ablation planning pattern can then be created or planned, which provides the ablation laser with a planned positioning of laser pulses along the determined path of the opening incision. The ablation laser can be an excimer laser, whereby the planned positioning of laser pulses causes ablation of corneal tissue and therefore runs from the surface of the cornea to the incision created within the cornea during the previously performed treatment. The opening incision can also include a cutting surface, which means it does not have to be fixed to a single path.

[0013] Finally, control data for the ophthalmic ablation laser can be provided, comprising the ablation planning pattern for tracing the opening incision. The treatment device and / or the ophthalmic ablation laser can then be controlled using the provided control data to create the opening incision. The control data can comprise a respective data set for positioning and / or focusing individual laser pulses in the cornea. Additionally or alternatively, the control data can include a respective data set for adjusting 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 respective laser.

[0014] The invention offers the advantage that a poorly created opening incision can be treated more effectively, either to create it completely or to increase the visibility of the opening incision. The use of an ablation laser has proven advantageous over the use of a photodisruption laser or femtosecond laser, since the photodisruption laser generates smaller cavitation bubbles, which could make it easier to miss the opening incision.

[0015] The invention also includes embodiments which provide additional advantages.

[0016] One embodiment provides for the determination of the planned course of the opening incision from predetermined eye recording data. This means that eye recording data can be acquired using a detection device, such as a camera, a microscope, and / or a tomography system, in particular an optical coherence tomography system. From the eye recording data, the inadequately generated opening incision in the cornea, in particular a course of the incompletely generated opening incision in the cornea, can then be determined, for example using image recognition. This incompletely determined course of the opening incision can then be extrapolated to the surface of the cornea, for example by regressing a course curve on the previously generated course of the opening incision.This design has the advantage that the ablation planning pattern can be created based on a visible, but deficient, course of the opening incision.

[0017] A further embodiment provides for the determination of the planned course from predetermined treatment data of the previously performed treatment. In other words, the course of the opening incision in the cornea can be known from the treatment data, which, for example, include the positioning of laser pulses from the previously performed treatment. This course can then be transferred or converted to the planned positioning of the laser pulses for the ablation laser. In particular, rescaling and / or rotation can be performed for the conversion of the course in order to adapt the positioning to the ablation laser. Furthermore, pulse sorting can be adjusted such that the course is carried out starting from the surface up to the incision within the cornea.This design has the advantage that no visible features of the opening incision need be present to provide the ablation planning pattern.

[0018] One embodiment provides that, during the previously performed treatment, a lenticule was created in the cornea as an incision within the cornea, and the opening incision is an incision for lenticule extraction. This means that, during the previously performed treatment, a femtosecond laser was used to create a lenticule comprising an anterior and posterior interface within the cornea. For the extraction or removal of the lenticule, an incision can be planned as the opening incision, connecting the lenticule within the cornea to the surface of the cornea. The lenticule can then be removed through this incision for refractive power correction.

[0019] Another embodiment provides for the opening incision to be a flap incision for creating a corneal flap. In this case, a femtosecond laser can be used to create a flap or corneal lamella within the cornea. The corneal lamella is created via the flap incision, extending to a hinge area on the surface of the cornea. This opens the corneal lamella or corneal flap, and the exposed corneal tissue is then irradiated with a laser. This technique is also known as femto-LASIK (laser in situ keratomileusis).

[0020] Another embodiment provides for the ablation laser to be an excimer laser. The excimer laser can be a gas laser capable of generating laser pulses in the ultraviolet wavelength range, allowing corneal tissue to be ablated from the outside inward. Alternatively, an argon laser, a CO2 laser, a dye laser, an erbium laser, and / or an Nd:YAG laser can be used as the ablation laser.

[0021] Preferably, the treatment device additionally comprises a femtosecond laser, which was used to create the incision within the cornea during the previously performed treatment. A femtosecond laser can emit laser pulses with a duration in the femtosecond range, whereby the pulses can create an optical breakthrough within the cornea within a focus in order to create an incision through a series of generated cavitation bubbles.

[0022] Preferably, the treatment device can comprise both an excimer laser and a femtosecond laser, allowing follow-up treatment, in particular tracing the path of the opening incision, to be performed immediately afterward. This saves time during treatment, as the patient does not have to be transferred to another treatment device.

[0023] A further aspect relates to a method for controlling a treatment device. The method comprises the method steps of at least one embodiment of a method as described above. Furthermore, the method for controlling the treatment device also comprises the step of transmitting the provided control data to at least one ophthalmic laser of the treatment device and controlling the treatment device and / or the laser with the control data.

[0024] The respective method may include at least one additional step that is executed precisely when a use case or application situation occurs that has not been explicitly described here. This step may, for example, include outputting an error message and / or a request for user feedback. Additionally or alternatively, it may be provided that a default setting and / or a predetermined initial state is set.

[0025] A further aspect of the invention relates to a control device which is designed to carry out the steps of at least one embodiment of one of the methods described above. For this purpose, the control device can have a computing unit for electronic data processing, such as a processor. The computing unit can comprise at least one microcontroller and / or at least one microprocessor. The computing unit can be embodied as an integrated circuit and / or microchip. Furthermore, the control device can comprise an (electronic) data memory or a memory unit. Program code which encodes the steps of the respective embodiment of the respective method can be stored on the data memory. The program code can comprise the control data for the respective laser.The program code can be executed by the computing unit, causing the control device to execute the respective embodiment. The control device can be embodied as a control chip or control unit. The control device can be comprised, for example, of a computer or computer network.

[0026] A further aspect of the invention relates to a treatment device with at least one ablation laser for the ablation of corneal tissue of a human or animal eye by means of optical breakthrough, in particular by means of photoablation, and at least one control device which is designed to carry out the steps of at least one embodiment of the method described above.

[0027] In a further advantageous development of the treatment device according to the invention, the control device can have at least one storage device for at least temporarily storing at least one control data set, wherein the control data set(s) comprise control data for positioning and / or focusing individual laser pulses in the cornea; and can have 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.

[0028] A further aspect of the invention relates to a computer program. The computer program comprises instructions that, for example, form a program code. The program code can comprise at least one control data set with the respective control data for the respective laser. When the program code is executed by a computer or a computer network, it is caused to execute the previously described method or at least one embodiment thereof.

[0029] A further aspect of the invention relates to a computer-readable medium (storage medium) on which the aforementioned computer program or its instructions are stored. To execute the computer program, a computer or a computer network can access the computer-readable medium and read its contents. The storage medium is designed, for example, as a data memory, in particular at least partially as a volatile or non-volatile data memory. A non-volatile data memory can be a flash memory and / or an SSD (solid state drive) and / or a hard disk. A volatile data memory can be a RAM (random access memory). The instructions can be present, for example, as source code of a programming language and / or as assembler and / or as binary code.

[0030] Further features and advantages of one of the described aspects of the invention may arise from the further development of another aspect of the invention. The features of the embodiments of the invention may thus be present in any combination with one another, unless explicitly described as mutually exclusive.

[0031] Additional features and advantages of the invention are described below with reference to the figure(s) in the form of advantageous exemplary embodiments. The features or combinations of features of the exemplary embodiments described below can be present in any combination with one another and / or with the features of the embodiments. This means that the features of the exemplary embodiments can supplement and / or replace the features of the embodiments, and vice versa. Thus, the invention also encompasses and discloses configurations that are not explicitly shown or explained in the figures, but which emerge and can be produced from the exemplary embodiments and / or embodiments through separate combinations of features.Thus, embodiments are also considered to be disclosed that do not have all the features of an originally formulated claim or that go beyond or deviate from the combinations of features set forth in the claims' references. The embodiments are shown in: Fig. 1 a schematic representation of a treatment device according to an exemplary embodiment; Fig. 2 a schematic process diagram for providing control data according to an exemplary embodiment.

[0032] In the figures, identical or functionally identical elements are provided with the same reference numerals.

[0033] The Fig. 1 shows a schematic representation of a treatment device 10 with an ablation laser 12 for ablating corneal tissue from a human or animal cornea 16 by ablation. The ablation laser 12 can, in particular, be an excimer laser designed to ablate corneal tissue by means of optical breakdown. In particular, the laser beam 20 generated by the laser 12 can be deflected toward the cornea 16 by means of a beam deflection device 22, such as a rotary scanner or deflection mirrors. Control data for controlling the ablation laser 12 and / or the beam deflection device 22 can be provided by a control device 18, so that the ablation laser 12 delivers laser pulses into the cornea 16 of the eye in an ablation pattern predefined by the control data. Alternatively, the control device 18 may be an external control device 18 with respect to the treatment device 10.

[0034] In a pretreatment, an incision 14 may have been made within the cornea 16, wherein the incision 14, for example, provides a lenticule within the cornea 16 for refractive correction of the cornea 16. Furthermore, an opening incision 24, which may in particular be an incision from the lenticule 14 to a surface of the cornea 16, may have been created. The opening incision 24 and the lenticule 14 may preferably be created within the cornea 16 using a femtosecond laser (not shown). The femtosecond laser may in particular be provided externally to the treatment device 10 or as a combined laser device together with the ablation laser 12 in a treatment device 10.

[0035] When making the opening incision 24, it may happen that it is created improperly. For example, the opening incision 24, starting from the lenticule 14, may not extend all the way to the surface of the cornea 16 because complications arose during the making of the opening incision 24 that prevented the opening incision 24 from being created completely. Alternatively or additionally, a poorly created opening incision 24 may also extend to the surface of the cornea 16, in which case it is subsequently no longer visible. Instead of an incision, a flap incision may also be provided as the opening incision 24, which leads to the creation of a corneal flap to the outer surface of the cornea 16.

[0036] Furthermore, a recording device 28 is shown, which can be provided with the treatment device 10 or externally thereto. The recording device 28 can be configured to acquire eye recording data. The eye recording data can be used, for example, to monitor a treatment and / or position laser pulses and / or to locate previously performed incisions in the cornea 16.

[0037] In order to complete the poorly created opening cut 24, the Fig. 2 procedures are carried out.

[0038] The Fig. 2 shows a schematic process diagram for providing control data for the ophthalmic surgical ablation laser 12 of the treatment device 10, wherein the process can be controlled by the control device 18.

[0039] In a step S10, a planned course 26 of the opening incision 24 in the cornea 16 is determined, wherein the planned course 26 is intended to extend to the outer surface of the cornea 16 in order to connect the incision 14 of the previously performed treatment, which was produced inadequately, with the surface. The planned course 26 of the opening incision 24 can, for example, be determined from predetermined eye recording data that can be recorded by the recording device 28. In particular, the previous course of the opening incision 24 can be determined by the recording device 28, wherein this can be extrapolated up to a surface in order to obtain the planned course 26. Alternatively or additionally, control data from the previously performed treatment in which the incision 14 was produced can also be available, from which the planned course 26 of the opening incision 24 is provided.

[0040] In a step S12, an ablation planning pattern for the ablation laser 12 can be generated, in which a planned positioning of laser pulses of the ablation laser beam 20 along the determined path 26 of the opening incision 24 is determined. In this case, a positioning of the laser pulses along the path 26 of the opening incision 24 can be planned, starting from the corneal surface and reaching the incision 14 within the cornea.

[0041] Finally, in a step S14, control data comprising the ablation planning pattern can be provided by the control device 18. The control device 18 can then control the treatment device 10, in particular the ablation laser 12 and / or the beam deflection device 22, such that the opening incision 24, starting from the surface of the cornea 16, is recut along the path 26 provided by the ablation planning pattern to the incision 14 within the cornea 16 in order to complete the incision and / or to provide improved visibility of the opening incision 24.

[0042] Overall, the examples show how an ablation-assisted opening incision 24 can be provided in the cornea 16.

Claims

[1] Method for providing control data for an ophthalmic ablation laser (12) of a treatment device (10), the method comprising the following steps carried out by means of a control device (18): - determining (S10) a planned course (26) of an opening incision (24) in a cornea (16), which is defined as a connection from an existing incision (14) within the cornea (16) to an outer surface of the cornea (16), wherein the opening incision (24) was produced defectively in a previously performed treatment; - generating (S12) an ablation planning pattern by which a planned positioning of laser pulses along the determined course (26) of the opening incision (24) from the surface of the cornea (16) to the existing incision (14) within the cornea (16) is provided; - Providing (S14) the control data for the ophthalmic surgical ablation laser (12) comprising the ablation planning pattern. [2] Method according to claim 1, wherein the determination of the planned course (26) of the opening cut (24) is carried out from predetermined eye recording data. [3] Method according to one of the preceding claims, wherein the determination of the planned course (26) is carried out from predetermined treatment data of the previously carried out treatment. [4] Method according to one of the preceding claims, wherein in the previously performed treatment a lenticule was created in the cornea (16) as an incision (14) within the cornea (16) and the opening incision (24) is an incision for lenticule extraction. [5] Method according to one of claims 1 to 3, wherein the opening incision (24) is a flap incision for producing a corneal flap. [6] Method according to one of the preceding claims, wherein the ablation laser (12) is an excimer laser. [7] Method according to claim 6, wherein the treatment device (10) additionally comprises a femtosecond laser with which the incision (14) was created within the cornea (16) of the previously performed treatment. [8] Control device (18) which is arranged to carry out a method according to one of the preceding claims. [9] Treatment device (10) with at least one ophthalmic ablation laser (12) for the ablation of corneal tissue of a human or animal eye by means of optical breakthrough, in particular by means of photoablation, and at least one control device (18) according to claim 8. [10] A computer program comprising instructions causing the treatment device (10) according to claim 9 to carry out a method according to any one of claims 1 to 7. [11] A computer-readable medium on which a computer program according to claim 10 is stored.

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