EQUIPMENT AND METHODS FOR REFRACTIVE SURGERY, PARTICULARLY FOR KERATOPLASTY

Abstract

Equipment and methods for refractive surgery, including for keratoplasty. The invention describes equipment and methods for the production and implantation of a lamella of a tissue or material for the purpose of correcting a corneal geometry at maximum precision that is thus improved in relation to the prior art. The invention facilitates restoration of normal corneal geometry together with optical functionality of the cornea which is improved in relation to the prior art. A planning device, a treatment system and a planning method are designed to couple a device coordinate systems of the laser devices involved and characterization devices by application of registration and to uniquely register the supplied measurement data for generating the lamella to be implanted to the device coordinate systems by a specific, defined edge geometry of a blank from which the lamella is produced, and by the lamella, and by additional system and method aids.

Claims

1-20. (canceled)

21. A treatment system for refractive surgery, including for keratoplasty, said treatment system comprising: a planning device that generates control data for the treatment system for the refractive surgery; a first laser device and at least one characterization device; a second laser device; wherein the first laser device, is configured to generate at least one incision in a cornea of an eye and is controllable by operation of the control data; the planning device including a first interface that supplies first measurement data regarding parameters of the cornea to the characterization device, a second interface that supplies second measurement data or model data about a lamella which is be insertable into the cornea following the generation of the cut surface, a third interface that transmits control data to the first laser device, and computing circuitry that determines the at least one cut surface in the cornea using the first measurement data and the second measurement data or model data, the computing circuitry generating a control data set that controls the first laser device and the at least one cut surface being generatable by the first laser device using the control data; wherein the second laser device is configured to process a blank to form the lamella and comprises a holder on which the blank is affixable during the treatment by the second laser device wherein the planning device is furthermore configured to generate control data for the second laser device of the treatment system, to control the second laser to process the blank to form the lamella to be shaped in a patient-specific fashion, and wherein the planning device further comprises a fourth interface that transmits control data to the second laser device; wherein the first laser device, the second laser device and the characterization device each have an equipment coordinate system, and the first laser device, the second laser device and the characterization device are coupled or couplable with respect to one another by a registration of the equipment coordinate systems, and the supplied second measurement data or model data of the lamella are registrable with respect to the equipment coordinate systems; and wherein the planning device further generates control data that facilitates active cooling of the holder, the blank or both.

22. The treatment system as claimed in claim 21, wherein the first laser device, comprises a femtosecond laser device.

23. The treatment system as claimed in claim 21, wherein the characterization device, comprises an OCT (optical coherence tomography) device.

24. The treatment system as claimed in claim 21, wherein second laser device of the treatment system, comprises an excimer laser device.

25. The treatment system as claimed in claim 21, wherein the planning device is furthermore configured to generate control data for the first laser device or a third laser device, an equipment coordinate system of which is likewise coupled to the aforementioned equipment coordinate systems by application of a registration, to generate or pre-process the blank, wherein the blank is able to be generated from a natural donor cornea or from artificial tissue, or the blank is pre-processable therein, by generating one or more cut surfaces in the donor cornea or the artificial tissue by operation of the first laser device or the third laser device.

26. The treatment system as claimed in claim 25, wherein the third laser device, comprises a further femtosecond laser device

27. The treatment system as claimed in claim 21, wherein the planning device is further configured to generate control data to institute a temperature regime that maintains a temperature below a maximum temperature for processing the blank to form the lamella using the second laser device.

28. The treatment system as claimed in claim 21, wherein the planning device is further configured to determine a substantially ring-shaped transition zone at an edge of the lamella, within which an edge thickness gradually transitions to a patient-specific thickness profile, and furthermore wherein control data are generated such that there is no processing of the edge of the lamella by the second laser device.

29. The treatment system as claimed in claim 25, wherein the planning device is further configured to define cut surfaces in the donor cornea or in the artificial tissue in such a way as to generate control data and transmit the control data to the first laser device or the third laser device with which a blank is generatable, the blank being defined by a correction zone situated in a center of the blank, a transition zone arranged around said correction zone and an edge zone arranged around said transition zone, the edge zone being provided for the subsequent separation prior to an insertion of the lamella into the cornea of the eye, and wherein the blank can be removed and affixed on a holder for purposes of processing with the second laser device.

30. The treatment system as claimed in claim 25, wherein the planning device is configured to define cut surfaces in the donor cornea or the artificial tissue in such a way as to generate control data and transmit the control data to the first laser device or the third laser device with which a blank is generatable, the blank being defined by a correction zone situated in the center of the blank and a transition zone arranged around said correction zone, and this blank is further processable by the second laser device in the original donor cornea or in the artificial tissue.

31. The treatment system as claimed in claim 30, wherein the planning device is further configured to define cut surfaces in the donor cornea or the artificial tissue in such a way as to generate control data and transmit the control data to the first laser device or the third laser device with which a blank is generatable, the blank further having an edge zone which is arranged around the transition zone and which is provided for subsequent separation prior to an insertion of the lamella into the cornea of the eye.

32. The treatment system as claimed in claim 29, wherein the planning device is configured to define the position of calibration marks in the transition zone and/or edge zone and to generate control data for the first laser device or the third laser device, by application of which control data these calibration marks are able to be introduced during processing with the first laser device or the third laser device, wherein the calibration marks are defined such that they are usable as a single or multiple orientation feature during a processing of the blank by operation of the second laser device.

33. The treatment system as claimed in claim 30, wherein the planning device is configured to define the position of calibration marks in the transition zone and/or edge zone and to generate control data for the first laser device or the third laser device, by application of which control data these calibration marks are able to be introduced during processing with the first laser device or the third laser device, wherein the calibration marks are defined such that they are usable as a single or multiple orientation feature during a processing of the blank by operation of the second laser device.

34. The treatment system as claimed in claim 33, wherein the planning device is further configured to define calibration marks which are arranged multiple times above one another and/or offset from one another and/or at different levels in the blank to be processed by the second laser device.

35. The treatment system as claimed in claim 21, wherein the planning device is configured to define a processing profile for the second laser device and determine the control data in such a way that the profile of the correction zone situated in the center of the blank and of the transition zone arranged around said correction zone is generatable by operation of the second laser device and an excavation is generatable in the edge zone arranged around the transition zone, thereby facilitating removal of a lamella carved out of the donor cornea or the artificial tissue, or thereby facilitating further processing of the blank on a holder, in such a way that the holder cannot be hit by a processing laser beam of the second laser device.

36. The treatment system as claimed in claim 21, wherein the planning device is configured to generate the control data taking into account a defined initial hydration state of the blank or of the lamella ex vivo, and the change in the hydration state of the lamella during or after the implementation.

37. The treatment system as claimed in claim 36, wherein the planning device is configured to generate the control data taking into account a defined initial hydration state of the blank or of the lamella ex vivo, and the change in the hydration state of the lamella during or after the implementation, by application of a constant expansion factor.

38. The treatment system as claimed in claim 21, wherein the planning device further generates control data that facilitates active cooling of the holder, the blank or both such that a temperature of the blank can be lowered in such a way that the blank is processed in a frozen state or wherein the planning device further generates control data that facilitates active cooling of the holder, the blank or both such that the temperature is lowered to a dewpoint of air in an airstream so that constant humidity is maintained thereby balancing condensation and evaporation of the blank .

39. The treatment system as claimed in claim 21, further comprising a temperature control device which comprises at least one of the following configurations: active electrical cooling by application of the Peltier element; active cooling by application of an introduced coolant; active cooling by an air flow; passive cooling by pre-cooling the holder with or without the blank affixed thereon; and a chamber, separated from surroundings, for processing the blank.

40. The treatment system as claimed in claim 21, further comprising a temperature sensor that monitors the temperature of the blank and/or of the holder during the processing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0131] The present invention will now be explained on the basis of example embodiments. In the drawings:

[0132] FIG. 1a is a diagram of an example first treatment system according to the invention with a first planning device according to the invention, which does not reflect the exact physical conditions.

[0133] FIG. 1b is a diagram of an example second treatment system according to the invention with a second planning device according to the invention.

[0134] FIG. 1c is a diagram of an example third treatment system according to the invention with a third planning device according to the invention.

[0135] FIGS. 2a to 2f depict various processing stages and processing variants of a blank in a donor cornea or an artificial tissue for a procedure for generating an implant/a patient-specific lamella as is obtainable, for example, with the aid of the planning device according to the invention

[0136] for the basic variant of processing the blank within the donor cornea or the artificial tissue up to the point where the patient-specific lamella is fully generated.

[0137] FIGS. 3a to 3f depict various processing stages and processing variants of a blank in a donor cornea or an artificial tissue for a procedure for generating an implant/a patient-specific lamella as is obtainable, for example, with the aid of the planning device according to the invention

[0138] for the basic variant of further processing the blank by application of the second laser device, in this case an excimer laser device, in such a way that the blank is taken from the donor cornea or the artificial tissue and affixed on a holder.

[0139] FIGS. 4a to 4c depict an implant following the processing with the laser devices of the treatment system according to the invention and before its insertion into a cut surface of the cornea in a recipient's eye.

DETAILED DESCRIPTION

[0140] In each of FIGS. 1a to 1c, the treatment system 1 comprises a planning device 2, a characterization device 4, which is configured to generate measurement data relating to parameters of the cornea 20 of an eye using examination radiation 8, a first laser device 3, which is a femtosecond laser device in this case and which is configured to generate a vacancy or, as illustrated here, a pocket cut 21 in the cornea 20 of a recipient's eye by application of a focused femtosecond laser beam 9 (the direction of incidence of the beam is not illustrated here—however, a person skilled in the art knows the optical setup of corresponding devices).

[0141] All characterization and laser devices of the treatment system 1 contain interfaces 5 to the planning device 2.

[0142] FIGS. 1a and 1b furthermore comprise a pretreating further laser device 6, which is likewise a femtosecond laser device, with the first femtosecond laser device 3 and the pretreating further femtosecond laser device being able to be one and the same device or else two different laser devices. The pretreating further laser device cuts a blank 23 from the cornea of a donor eye 22 using a focused femtosecond laser beam 10. FIGS. a to 1c furthermore comprises a post-treating second laser device, in this case an excimer laser device 7, which carves the lamella 24 to be implanted from the blank 23 using excimer laser radiation 11, said lamella then ultimately being implanted in the pocket 21 of the cornea of the recipient's eye 20.

[0143] The planning device 2 is configured to couple the equipment coordinate systems of the involved laser devices 3, 6, 7 and characterization devices 4 by use of a registration and to uniquely register the supplied measurement data of the lamella 23 to be implanted to the equipment coordinate systems.

[0144] While the pocket cut 21 is initially generated in the cornea of the recipient's eye 20 in FIG. 1a, and the blank 23 is only subsequently generated in the donor eye and removed from the latter in order to subsequently be formed into the lamella 24 as intended to be handled, the blank 23 is initially processed in full to form the lamella 24 in FIG. 1b. Only then is a pocket cut 21 implemented in the cornea of the recipient's eye 20 for the purposes of preparing the implantation.

[0145] In FIG. 1c, in turn, work is carried out using standardized blanks 23 (for example made of an artificial tissue material), which are then only still post-processed to form the lamella 24. However, this also shows the affixment of the blank 23 to a holder 25 while being processed by application of the excimer laser device 7 as second laser device. The holder is cooled while the blank is processed.

[0146] FIGS. 2a to 2f show various processing stages and processing variants of a blank 23 in a donor cornea or an artificial tissue for a procedure for generating an implant/a patient-specific lamella 24 as is obtainable, for example, with the aid of the planning device 2 according to the invention—for the basic variant of processing the blank 23 within the donor cornea or the artificial tissue to the point where the patient-specific lamella 24 is generated.

[0147] In this case, FIG. 2a represents a donor cornea with its individual layers, the epithelium layer 101, the Bowman's membrane 102 and the corneal stroma 103. Moreover, the cuts that fundamentally separate the blank 23 from the donor cornea are shown: The lamellar cut 104 and the side cut 105.

[0148] FIG. 2b moreover represents the implant 106, to be generated, in the form of the patient-specific lamella 24 and, following therefrom, the ablation volume 107 intended to be ablated using the second laser device 7. Also shown is the excavation 108 intended to subsequently serve the simplified separation of the implant 106 from the donor cornea (or an artificial tissue). Moreover, also visible in FIG. 2b are the two outer boundaries of the correction zone 109, 110, and the upper outer boundary of the implant 111, which represents the intersection of side cut 105 and final implant top side.

[0149] In addition to the regions, cuts and markings specified in FIGS. 2a and 2b, FIG. 2c represents the outer boundary of the transition zone 112, 113.

[0150] In addition to the regions, cuts and markings already specified in FIGS. 2a to 2c, FIG. 2d shows calibration marks 114. With the aid thereof, it is then for example possible to modify the shape of the excavation 108 in relation to the shape 115 of the excavation shown in FIGS. 2b and 2c. By introducing calibration marks 114 by application of the first 3 or further laser device 6 (that is to say the femtosecond laser device in this case), the removal profile in the edge regions is subsequently controlled during the ablation process by application of the second laser device 7 (in this case the excimer laser device).

[0151] In addition to the aforementioned calibration marks 114, FIG. 2e shows further calibration marks: Calibration marks above the implant in its edge region 116 and calibration marks next to the implant, and stacked calibration marks 117, 118.

[0152] Additionally, a side cut 119 is planned with the first 3 or further laser device 6, the femtosecond laser device, in FIG. 2f, said side cut hence defining the height of the implant 106 in its edge zone, in particular of the patient-specific lamella 24 as final product of planning and processing the blank 23, more reliably than if this height is generated only by application of the ablation by way of the second laser device 7, the excimer laser device.

[0153] Thus, the patient-specific lamella 24 is carved from a blank 23 in the donor cornea in these variants of FIGS. 2a to 2f The implant 106 is only removed from this donor cornea or the artificial tissue following this processing.

[0154] FIGS. 3a to 3f show various processing stages and processing variants of a blank 23 in an artificial tissue or a donor cornea for a procedure for generating an implant/a patient-specific lamella 24 as is obtainable, for example, with the aid of the planning device 2 according to the invention—for the basic variant of further processing the blank by application of the second laser device 7, in this case an excimer laser device, in such a way that the blank 23 is taken from the artificial tissue and affixed on a holder 25. This is the preferred way, especially when processing artificial tissue, since a reliable temperature regime should be ensured in the case of an affixment on a holder 25 during the processing with the second laser device 7, that is to say an excimer laser device. In this respect, artificial tissue is even more sensitive than the natural tissue of a donor cornea.

[0155] In this case, FIG. 3a initially represents an artificial tissue which virtually “reproduces” a natural cornea, with epithelium layer 101, Bowman's membrane 102 and corneal stroma 103. Moreover, the cuts that fundamentally separate the blank 23 from the artificial tissue are shown: The lamellar cut 104 and the side cut 105, which in this case is not guided from the lamellar cut 104 up to the epithelium layer 101, but only guided into the stromal layer. However, the blank 23 is only really separated from the artificial tissue by the modified side cut 120.

[0156] In addition to the regions, cuts and markings already specified in FIG. 3a, FIG. 3b also represents the implant 106 to be generated, in the form of the personalized lamella, and, following therefrom, the ablation volume 107 and an excavation 108: It is evident from the representation of the excavation 108 in particular that the modified side cut 120 is planned so that the excavation 108 is completely comprised in the blank 23 separated from the artificial tissue by the cuts. Moreover, once again, also visible in FIG. 3b are the two outer boundaries of the correction zone 109, 110, and the upper outer boundary of the implant 111, which represents the intersection of side cut 105 and final implant top side.

[0157] In FIG. 3c, the blank 23 has firstly been taken from the artificial tissue and has been affixed to a holder 25. In addition to the regions, cuts and markings specified in FIGS. 3a and 3b, the outer boundary of the transition zone 112, 113 is also represented here.

[0158] In addition to the regions, cuts and markings already specified in FIGS. 3a to 3c, FIG. 3d in turn shows calibration marks 114. In this case, too, the shape 115 of the excavation 108 can be influenced with the aid of the calibration marks 114.

[0159] In addition to the aforementioned calibration marks 114, FIG. 3e shows further calibration marks: Calibration marks above the implant in its edge region 116 and calibration marks next to the implant 106, and stacked calibration marks 117, 118—all of these in more or less the same way as when processing the blank 23 to form a patient-specific lamella 24 in the donor cornea. However, this variant allows a temperature regime when processing the blank 23 with the second laser device 7, the excimer laser device, to be introduced and maintained very precisely from the moment the blank 23 is affixed to the holder 25.

[0160] Additionally, a side cut 119 is planned with the first 3 or further 6 laser device, the femtosecond laser device, in FIG. 3f, said side cut hence reliably defining the height of the implant 106 in its edge zone, in particular of the patient-specific lamella 24 as final product of planning and processing the blank 23.

[0161] FIGS. 4a to 4c finally show an implant 106 following the processing with the laser devices 3, 7, 6 of the treatment system 1 according to the invention and before its insertion into a cut surface 21 of the cornea in a recipient's eye.

[0162] FIG. 4a represents such an implant 106, the blank 23 of which was processed on a holder 25 using the second laser device 7, the excimer laser device, in a plan view, while FIGS. 4b and 4c show the same implant 106 in a side view. The actual edge of the lamella 24 to be implanted was precisely carved out by way of the excavation. However, it is protected until after the processing thereof using the second laser device 7. The separation point for finally removing this extended “protective edge” was already created by the side cut of the blank 23 at the start of the entire production process for the patient-specific lamella 24. This patient-specific lamella 24 then remains following the actual separation of the “protective edge”, as shown in FIG. 4c, and can be inserted into the prepared cut surface 21 or structure in the cornea 20 of the recipient's eye.

[0163] The aforementioned features of the invention, which are explained in various exemplary embodiments, can be used not only in the combinations specified in an exemplary manner but also in other combinations or on their own, without departing from the scope of the present invention.

[0164] A description of a piece of equipment relating to method features is analogously applicable to the corresponding method with respect to these features, while method features correspondingly represent functional features of the equipment described.