Generation of curved incisions inside the cornea

Description

[0001] The invention relates to a device for isolating a lenticule in the cornea of ​​an eye, comprising a laser beam source configured to emit pulsed laser radiation with a wavelength penetrating the cornea, a beam shaping device comprising beam optics which focuses the pulsed laser radiation into a focus in the cornea, and a beam deflection device which shifts a focus of the radiation in the cornea, wherein a control device is provided which is configured to control the laser beam source and the beam shaping device in order to isolate a lenticule in the cornea which is bounded by a cut surface.

[0002] The invention further relates to a method for isolating a lenticule in the cornea of ​​an eye, wherein at least one cutting surface is defined in the cornea that delimits the lenticule, and the cutting surface in the cornea is created by emitting pulsed laser radiation, wherein pulsed laser radiation is used that has a wavelength penetrating the cornea and a focus of the laser radiation is shifted in the cornea. The invention does not include any surgical treatment of the living human or animal eye.

[0003] The shape of the cornea's anterior surface is crucial for the eye's imaging properties. Therefore, it has long been known to reshape the cornea to correct refractive errors, with the aim of modifying its anterior surface and thus its refractive properties, thereby correcting the refractive error. Prior art surgical procedures have been developed for this purpose, in which a flap is detached from the cornea, folded back, and then material is removed from the exposed interior of the cornea. The flap is then folded back into place, and the cornea has a differently shaped anterior surface due to the material removal. This correction principle is known in the prior art, among other names, as LASIK and will be referred to below as flap-releasing refractive correction. In early embodiments, the flap was detached using a mechanical keratome.The cornea is flattened using a flat contact lens, and a cut is made to create the flap using a mechanical keratome. In advanced training, so-called laser keratomes are now used. One such laser keratome is from Ziemer Ophthalmic Systems AG, Port, Switzerland. Its beam deflection is specifically designed to create the flap that is lifted. Another laser keratome was developed by Intralase Inc., USA, which is now part of Abbott Laboratories, Illinois, USA. Both laser keratomes operate with pulsed laser radiation, although they differ in repetition rates and pulse energies.

[0004] Surgical refractive correction has evolved into procedures that isolate and extract material from the cornea. This material is typically lenticule-shaped, hence these procedures are referred to here as lenticule-extracting procedures or devices. For clarity, the volume to be isolated and extracted is also described as a "lenticule," even though in certain applications a non-lenticule-shaped volume needs to be isolated and extracted.

[0005] The devices and methods mentioned at the outset relate to the principle of lenticule extraction. Lenticule-extracting devices and methods have the advantage that the anterior corneal surface is damaged in a much smaller area. A nearly completely ring-shaped incision on the anterior corneal surface, as required to detach a flap exposing the corneal interior, is no longer necessary. Instead, a small incision at the edge, leading to the isolated volume, is sufficient. This volume can then be extracted, if necessary after prior fragmentation of the isolated material. However, the principle of lenticule extraction requires that the incision surfaces isolating the lenticule within the cornea be created with high precision.To achieve refractive error correction, and to minimize tissue loss, at least one of the cut surfaces defining the lenticule should remain at a non-constant distance from the anterior corneal surface. This differs from the approach that detaches and flaps a corneal flap, where the single, flap-generating cut surface can easily be at a constant distance from the anterior corneal surface, i.e., parallel to it. When, in the flap-generating cut, the anterior corneal surface is flattened with a flat contact lens, only a cut surface needs to be created that, except for its edges, is parallel to the surface of the contact lens and is itself flat.

[0006] Lenticule-extracting refractive error correction is fundamentally described in WO 2004 / 105660 A1 and WO 2004 / 105661 A1. Further developments are known in the prior art. For example, WO 2005 / 011547 A1 discloses the use of contour lines for rapid lenticule isolation, and WO 2008 / 055697 A1 provides calculation methods for selecting the lenticule's boundary surfaces, i.e., the generating cutting surfaces. This document specifically discloses the ability to divide the cutting surfaces bounding the lenticule into an anterior flap surface, which lies at a constant distance from the anterior corneal surface, and a posterior lenticule surface, which does not lie at a constant distance from the anterior corneal surface. The distance between these surfaces, and thus their shape, influences the corneal curvature after correction.

[0007] A device or method according to the preamble of the independent claims is known from DE 102 02 036 A1.

[0008] WO 2008 / 055 705 A1 and WO 2008 / 055 706 A1 deal with the problem of image field curvature when using a non-planar contact lens and the generation of control data for the surgical procedure.

[0009] The incision is typically created using pulsed laser radiation. The target points of the laser radiation are arranged along a trajectory that lies within the incision and ultimately defines the incision. WO 2008 / 055698 A1 describes the arrangement of the target points along the trajectory, specifying that a target point is not required for every laser pulse emitted into the cornea.

[0010] WO 2008 / 131 878 A1 addresses the question of how further treatment can be performed after the termination of a laser surgical procedure, taking into account the tissue changes already created in the cornea. DE102008056488 A1 also concerns an ophthalmic laser system, specifically for the purpose of post-operative treatment of the cornea.

[0011] WO 2009 / 059 711 A1 and WO 2009 / 059 730 A1 deal with different profiles of the lenticule to be extracted for certain refractive error corrections, namely hyperopia correction, and specify minimum values ​​for the lenticule.

[0012] WO 2003 / 059 563 A2 discloses operating parameters for a laser device for the surgical correction of refractive errors by means of lenticule extraction. The same applies to EP 1 628 606 B1.

[0013] US 2012 / 0078240A1 describes a laser device and a method for performing a refractive procedure on an eye.

[0014] DE 10 2008 062 658 A1 concerns laser-assisted keratoplasty, in which a lamella is to be cut on the back of the cornea.

[0015] The VisuMax femtosecond laser keratome from Carl Zeiss Meditec AG is known in the prior art for the lenticular extraction procedure. It uses a femtosecond fiber laser that emits in the infrared spectral range and delivers laser pulses with a pulse repetition rate of 500 kHz, which are focused into the cornea.

[0016] The time required to create the incision surface is crucial for both the quality of refractive correction and patient acceptance. As the procedure lengthens, the risk of disruptive eye movements increases. These movements can reduce the accuracy of the incision surface or even prevent the creation of a continuous incision, necessitating the termination of the procedure. Furthermore, a prolonged procedure is an undesirable burden for the patient.

[0017] In lenticular ablation, the quality of the optical correction is largely determined by the accuracy of the volume removal after the lenticular flap is detached. The position of the flap itself is of secondary or even negligible importance. In contrast, the precise positioning of the cut surfaces within the cornea is crucial for the quality of the result of lenticular ablation. Since the cut surface is created by adjusting the focus of the pulsed laser beam along a path, the positioning accuracy of the focus within the cornea is ultimately important. It is essential to remember that this is living tissue, which can change during the procedure and does not necessarily respond linearly to parameter changes.

[0018] The invention is therefore based on the objective of further developing a device of the type mentioned above or a method of the type mentioned above in such a way that rapid cutting surface generation with high precision is achieved.

[0019] The invention is defined in the independent claims. The claimed method does not include any surgical treatment of the living human or animal eye.

[0020] A device for isolating a lenticule in the cornea of ​​an eye has in particular the following features: a laser beam source configured to emit pulsed laser radiation with a pulse frequency of 1.2 MHz to 10 MHz, a pulse energy of 1 nJ to 200 nJ and a wavelength penetrating the cornea, a beam shaping device comprising beam optics having an image field and focusing the pulsed laser radiation into the cornea at a focus located within the image field and having a maximum diameter of less than 3 µm, and a beam deflection device that shifts the focus in the cornea and within the image field, wherein the focus moves along a path when the image field is stationary, a control device configured to control the laser beam source and the beam shaping device in order to isolate the lenticule in the cornea by defining the path, the lenticule being bounded by at least one cross-sectional surface that is curved relative to an anterior surface of the cornea.

[0021] In a procedure for isolating a lenticule in the cornea of ​​an eye, in particular In the cornea, at least one cutting surface is defined that delimits the lenticule and is curved relative to an anterior surface of the cornea; a path is defined that lies in the cutting surface; pulsed laser radiation is emitted into the cornea with a pulse frequency of 1.2 MHz to 10 MHz, a pulse energy of 1 nJ to 200 nJ and a wavelength penetrating the cornea; a beam optic is used which has an image field and focuses the pulsed laser radiation into the cornea into a focus that lies within the image field and has a maximum diameter of less than 3 µm; and the focus is shifted in the cornea and within the image field, with the focus moving along the path when the image field is stationary.

[0022] The invention combines various features that together enable the creation of a cutting surface that is curved relative to the anterior surface of the cornea. This is not a conventional, lamellar-removing cutting surface, but rather a cutting surface that, in a plane through the eye containing the visual axis or optical axis, does not run at a constant distance from the anterior surface of the cornea. The curvature, more precisely a two-dimensional curvature, relative to the anterior surface of the cornea, is, according to the invention, related to a central area around the optical axis or visual axis of the eye, which, for example, has a diameter of no more than 10 mm.This is the area essential for optical correction, and in this area, typical initial laser incisions of lamellar correction principles have a constant distance between the anterior surface of the cornea and the incision surface, which causes the lamella to expose the interior of the cornea.

[0023] The combination according to the invention goes beyond a simple aggregation of features and achieves a combined effect for the following reasons: The individual laser pulses, which form the intersection along the path, have different effects in the cornea, depending on pulse energy, pulse frequency and focus diameter.

[0024] Regarding tissue separation using pulsed laser radiation, two different operating regimes can be identified. These different processes are subsequently referred to as "tissue splitting" and "tissue cutting".

[0025] When laser pulses are focused into the cornea under certain conditions, tissue dissolution occurs within the focal volume, releasing gases under high pressure that exert mechanical forces on the surrounding tissue. Corneal tissue consists of a lamellar collagen structure, and according to the inventors, these mechanical forces create micro-ruptures along the lamellae. Thus, in addition to the primary process of tissue dissolution within the focal volume, a secondary effect occurs, leading to tissue splitting along the collagen structure. However, when using comparatively lower pulse energies and higher repetition rates, the secondary effect of tissue splitting no longer occurs; instead, the tissue dissolution generated within the focal volume alone causes the separation. The corneal tissue is therefore cut largely independently of the collagen structure.

[0026] The inventors recognized that there is no abrupt transition between tissue splitting and tissue cutting. Within the parameter space of laser pulse application, there is a transitional range in which one or the other mechanism contributes more or less significantly to the tissue separation process. Furthermore, it was found that in lenticular-extracting procedures and devices used in clinical practice, only parameter sets have been employed to date that resulted in the secondary effect of tissue splitting playing a substantial role in the separation process. Currently, the only parameter set used in clinical practice that exclusively targets tissue cutting is the laser keratome from Ziemer Ophthalmic Systems AG, Port, Switzerland.However, according to current public knowledge, this device is not capable of producing cut surfaces that are curved relative to the anterior surface of the cornea, and, as already stated at the outset, the working regime offers no significant application advantage in the lamellar dissolving procedure and is therefore not important.

[0027] It must be emphasized that the identification of the different working regimes, i.e., the influence of parameters on whether tissue splitting or tissue cutting predominates in lenticule production, was first mentioned by the inventors. This distinction between working regimes for this method is not found in the prior art. Nor is the literature familiar with the assignment of individual implementations of the prior art to these working regimes.

[0028] Through their work, the inventors further discovered that, with regard to the achievable accuracy, a significant difference between tissue splitting and tissue cutting only arises when curved cuts are made. This is because tissue splitting generally always proceeds along the lamellae of the collagen structure of the corneal tissue. Therefore, with lamellar cuts, there is no advantage or disadvantage to the processing result between lamellar splitting and lamellar cutting. The situation is different with curved cut surfaces: due to the physiologically determined lamella thickness and structure, it is not possible to place a curved cut surface with high precision at any desired location in the cornea when using tissue splitting techniques.

[0029] The tissue cutting mechanism allows for much more precise positioning of the cutting surface and, in particular, greater dimensional accuracy. The inventors attribute this to the fact that, unlike tissue splitting, the cutting surface in a tissue cutting process does not necessarily lie at the interfaces between lamellae of the corneal tissue's collagen structure, but can also be located within a lamella. This avoids the pre-tearing (the splitting leading ahead of the advancing laser pulse sequence) that occurs in tissue splitting at the lamellar plane, and the separation is achieved precisely at the focal point. Tissue splitting, on the other hand, can be understood as a kind of digitization of the cutting surface position, with the smallest unit being the lamella thickness, since a tissue-splitting cut surface tends to always lie at the interfaces between individual lamellae of the corneal tissue.This is not a disadvantage for cuts made at a constant distance from the anterior corneal surface, as the lamellar structure follows the anterior corneal surface with good accuracy. However, for curved lenticule cut surfaces, whose distance from the anterior corneal surface varies depending on the radius and, if applicable, the angle, this type of cut surface generation proves to be a disadvantage.

[0030] These relationships result in the parameter range according to the invention, with respect to pulse frequency, pulse energy, and focus diameter, leading to particularly reliable tissue separation in which the tissue cutting process predominates. The combination with the generation of a cutting surface that is curved relative to the anterior corneal surface and thus necessarily does not follow the interface between the lamellae of the collagen structure of the corneal tissue (which, incidentally, runs largely parallel to the anterior corneal surface), therefore leads to particularly precise cutting surface positioning and high dimensional accuracy. In the working range according to the invention, the contribution of tissue splitting is reduced in favor of the tissue cutting effect, so that for lenticule extraction, the cutting surface and thus the isolation of the lenticule more precisely follow the specified values.

[0031] The tissue-cutting effect is particularly pronounced when the pulse energy is less than 100 nJ. The pulse energy ranges from 10 nJ to 80 nJ. For generating the curved cut surface, it is further advantageous if, alternatively or additionally, the beam optics incorporate a lens with a numerical aperture of at least 0.33 in the cornea. A pulse duration of no more than 1 ps has proven particularly favorable for the pulsed laser radiation at infrared wavelengths.

[0032] The wavelength of the laser radiation used is such that it can penetrate the cornea (transmittance ≥ 0.8) and, through nonlinear effects within the cornea, causes tissue separation. A wavelength of 1030–1060 nm has proven effective for this purpose. Alternatively, laser radiation in the ultraviolet spectral range between 300 nm and 400 nm can also be used. While it tends to have a higher linear interaction component (absorption) than the aforementioned infrared radiation, it is also suitable if the focus diameter does not exceed 2 µm and the pulse frequency does not exceed 2 MHz. When laser pulses from this ultraviolet wavelength range are used, pulse durations of a few nanoseconds can also be effectively employed.

[0033] The lenticule is isolated by shifting the focus within the field of view of the beam optics used, ensuring the image field remains stationary relative to the cornea being treated. This differs from the laser keratome of Ziemer Ophthalmic Systems AG, which employs a microscope objective with a field of view far too small to fully capture the corneal area to be treated. Therefore, the microscope objective, and consequently the image field, is shifted in this laser keratome. Creating a curved cut surface with this method is not feasible with reasonable effort. Consequently, this laser keratome flattens the anterior surface of the cornea using a planar contact lens, ensuring the resulting cut surface is automatically parallel to the corneal anterior surface.The invention, however, uses a stationary image field for which a diameter of at least 3 mm, preferably at least 6 mm, and particularly preferably at least 7 mm is advantageous with regard to the area to be processed. Smaller image fields make it more difficult to generate the section surface or are too small for the lenticels typically required for isolation.

[0034] Since the incision is made by shifting the focus within the field of view along a path that lies within the incision area, virtually any desired curved incision surface can be created in the cornea with suitable three-dimensional focus adjustment. Therefore, it is no longer necessary to flatten the cornea. Instead, a curved contact lens can be used, preferably with a contact surface of this lens that rests on the anterior surface of the cornea having a radius of curvature of no more than 50 mm, preferably no more than 20 mm. The curvature of the contact surface of the contact lens determines the curvature of the cornea during the procedure.

[0035] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations given, but also in other combinations or on their own, without leaving the scope of the present invention.

[0036] In particular, the invention, in a slightly modified form, is also advantageously applicable for the production of curved sections in other elements of the eye, for example in the lens or the vitreous body.

[0037] The invention will now be explained in more detail, for example with reference to the accompanying drawings, which also reveal essential features of the invention. They show: Fig. 1 a schematic representation of a device for performing lenticular-extracting refractive error correction, Fig. 2 a simplified cross-sectional view through the cornea to illustrate the lenticule to be isolated and extracted, and Fig. 3 a projection of a cross-sectional surface bounding the lenticule to illustrate the creation of the cross-sectional surface.

[0038] Fig. 1 Figure 1 schematically shows a device 1 for performing lenticular-extracting refractive error correction. The device 1 comprises a laser 2 that provides pulsed laser radiation. In the described embodiment, the laser 2 emits a pulsed raw beam 3 with a wavelength that penetrates the corneal tissue, enabling processing there by means of nonlinear effects. The raw beam 3 is shaped by a pulse shaper 4 with respect to the pulse duration. A pre-distortion known from the prior art can be applied to ensure that, after passing through the further optical path of the beam path, the desired pulse length of, for example, ≤ 1 ps is present in the material, i.e., in the cornea of ​​the eye. The pulse shaper 4 and the laser 2 together form a laser beam source 5, which emits a pulsed laser beam 6 of the desired pulse length.

[0039] The pulsed laser beam 6 passes through a scanner 7, which preferentially causes a two-dimensional deflection perpendicular to the direction of propagation of the laser radiation. The scanned laser beam 6 is focused into the cornea by a lens 8. The scanner 7, together with the lens 8, forms a beam shaping device 9, which ensures that the pulsed laser radiation 6 is focused to adjustable locations in the cornea of ​​an eye, with a focus diameter of less than 3 µm.

[0040] The laser beam source 5 can optionally include a so-called pulse picker, which can, for example, be part of the pulse shaper 4. This pulse picker modifies the raw beam 3 with respect to the frequency of the laser radiation pulses that have a processing effect on the cornea. For example, it is possible to configure the laser 2 to provide a raw beam 3 with a pulse frequency that is significantly higher than the pulse frequency desired for the processing laser pulses of the laser beam 6. The pulse picker then reduces the frequency of the effective laser radiation pulses by neutralizing individual laser radiation pulses with respect to their processing effect. This can be achieved, for example, by the pulse picker increasing the pulse duration. The significance of the pulse picker, which is known in the prior art, will be explained later with reference to the Fig. 3 will be explained.

[0041] In the Fig. 1 In the embodiment shown, the pulse frequency of the pulsed laser beam 6 is between 1.2 MHz and 10 MHz, the frequency referring to those pulses that have a processing effect, i.e. pulses that have not been rendered harmless by a pulse picker that may be present.

[0042] The energy of these pulses of the pulsed laser beam 6 lies between 10 nJ and 80 nJ.

[0043] The wavelength of the laser beam 6 lies in a range of 1030 nm to 1060 nm or from 300 nm to 400 nm or another spectral range that can penetrate the cornea, for which the cornea therefore has a transmittance of at least 0.8.

[0044] The device 1 further comprises a contact lens 10, which serves to fix the eye 11 and also to give a desired and known shape to the anterior surface of the cornea 12 of the eye 11. The corresponding contact surface of the contact lens 10 has a radius of curvature of 50 mm or less, particularly preferably 20 mm or less.

[0045] The lens 8 focuses the laser radiation 6 into a focus 13 located within the cornea 12. The focus 13 has a maximum diameter of 3 µm, preferably a maximum of 2 µm. The maximum diameter is the largest diameter measured along the major semi-axis, for example, in the case of an elliptical focus spot. In the case of a circular spot, the spot diameter is the relevant measurement.

[0046] Fig. 1 The dashed line shows that, depending on the effect of scanner 7, the focus 13 lies at different locations in the cornea 12 of the eye 11. The scanner 7, in its design, causes... Fig. 1 a deflection perpendicular to the main direction of incidence of the laser radiation 6. An adjustment of the focus position along the main direction of incidence is achieved by suitable control of the lens 8, which is designed to be suitable for a z-adjustment.

[0047] The laser beam source 5 (in the design of the Fig. 1 realized by laser 2 and pulse shaper 4) as well as the beam shaping device 9 (in the design of the Fig. 1 The elements realized by scanner 7 and lens 8 are connected via control lines (not otherwise specified) to a control unit 14, which appropriately controls these elements. The control unit 14, through this control, creates a cross-sectional area in the cornea. The corresponding relationships are shown in a cross-sectional view in Fig. 2 depicted, which schematically shows the cornea 12.

[0048] By adjusting the focus 13 of the pulsed laser beam 6, a lenticule 15 is isolated in the cornea 12. The lenticule 15 is bounded anteriorly by a flap surface 16 and posteriorly by a lenticule surface 17. To keep the boundaries of the lenticule 15 as simple as possible, the flap surface 16 is located at a constant distance from the anterior surface 18 of the cornea 12. The flap surface 16 is therefore not curved relative to the anterior surface 18. This differs from the lenticule surface 17, which is curved relative to the anterior surface 18. Without such curvature, the removal of the lenticule 15 would not change the curvature of the anterior surface 18 of the cornea 12. The lenticule surface 17, which is curved relative to the anterior surface 18, changes the curvature of the anterior surface 18 of the cornea 12 when the lenticule 15 is removed. This removal is performed by a [missing information - likely a specific instrument or device] located in the Fig. 2 The lateral section not shown, which leads, for example, from the flap surface 16 to the front surface 18 at the edge of the lenticel 15, allows the isolated lenticel 15 to be extracted, if necessary after prior comminution of the material of the lenticel 15. In the illustration of the Fig. 2 Flap surface 16 and lenticule surface 17 are symmetrical about the optical axis OA. This is automatically achieved for flap surface 16 when it has a constant distance to the front surface 18.

[0049] The interfaces of the lenticule 15 can, of course, include additional surfaces besides the flap surface 16 and the lenticule surface 17. For example, in a lenticule 15 that is thinner on the optical axis OA than in regions farther from the axis, an additional boundary surface can be provided, which connects the flap surface 16 with the lenticule surface 17, which then has a more strongly curved profile than the flap surface 16 and the front surface 18.

[0050] The cross-sectional surfaces for isolating the lenticel 15 are generated by shifting the focus 13 along a path that lies within the corresponding surface. This is exemplified in Fig. 3 This is shown using the lenticule surface 17, which is elliptical here for clarity. This is intended to demonstrate that the device 1 can correct not only spherical aberrations but also astigmatism. Fundamentally, when correcting higher aberrations, the lenticule 15 is no longer rotationally symmetrical about the optical axis OA. Fig. 3 shows an unfolding of the lenticular surface 17 into the drawing plane. The dashed line indicates... Fig. 3 A path 19 is marked. The position of the focus 13 is adjusted along this path. This usually requires not only an adjustment perpendicular to the optical axis OA, but also an adjustment of the focus position along the optical axis OA. This is shown in Fig. 3 therefore not recognizable, since this figure shows an unfolding of the lenticular surface 17 into the drawing plane, which is why the path 19 in the representation of the Fig. 3 lies in a plane. Considering the section through lenticular 15 in Fig. 2 It becomes clear that with increasing distance from the optical axis OA, the z-position of the focus is also shifted away from the front surface 18.

[0051] Along railway line 19 of the Fig. 3 Target points 20 are marked. Each of these points represents a point onto which a laser pulse of the pulsed laser radiation 6 is emitted. By arranging the target points 20 along the path 19 and by appropriately selecting the path 19, the lenticular surface 17 is formed as a cross-sectional area. The distances between the target points 20 are chosen such that as few material bridges as possible remain, thus generating a complete cross-sectional area of ​​the lenticular surface 17.

[0052] Based on Fig. 3 It is easy to understand why it is advantageous to make the pulse frequency of the pulsed laser beam 6 variable. If the aim is to arrange the target points 20 as equidistantly as possible, the pulse frequency and the traverse speed of the steel forming device 9 must be adjusted to each other. Since a laser 2 is generally only adjustable with considerable effort at high pulse frequencies, it is advantageous to first provide a raw beam 3 with the laser 2, which has a pulse frequency greater than or equal to the maximum pulse frequency desired for the laser beam 6. It can be simpler to implement such a laser 2 and combine it with a pulse picker than to build a laser whose pulse frequency is directly adjustable. In this way, the pulse frequency can be adapted to the traverse speed, and the time required for surface generation is minimized.

[0053] The parameters for pulse energy, pulse frequency, focus diameter, and optionally pulse duration mentioned in this figure description and in the general part of the description result in the creation of the section surfaces using a tissue separation mechanism that utilizes tissue cutting and, essentially, tissue splitting. This allows for the highly precise realization of a desired position for the boundary section surfaces of the lenticule 15.

Claims

1. An apparatus for isolating a lenticule (15) in the cornea (12) of an eye (11), comprising - a laser beam source (5) configured to emit pulsed laser radiation (6) with - a pulse frequency of 1.2 MHz to 10 MHz, - a pulse energy of 1 nJ to 200 nJ, and - a wavelength that penetrates the cornea (12), - a beamforming device (9) comprising - beam optics (8) that focus the pulsed laser radiation (6) into the cornea (12) at a focus (13) having a maximum diameter of less than 3 µm, and - a beam deflection device (7) that shifts the focus (13) within the cornea (12), wherein the focus (13) travels along a path (19), - a control device (14) configured to control the laser beam source (5) and the beamforming device (9) to isolate the lenticule in the cornea (12) by specifying the path (19), which lenticule is bounded by at least one cut surface (17) that is curved relative to a front surface (18) of the cornea (12), characterized in that - the laser beam source (5) is configured to emit the pulsed laser radiation (6) with a pulse energy of 10 nJ to 80 nJ and / or the beam optics comprise an objective (8) with a numerical aperture of at least 0.33.

2. The apparatus according to claim 1, wherein the laser beam source (5) is configured to emit the pulsed laser radiation (6) with a wavelength of 1030 nm to 1060 nm.

3. The apparatus according to claim 2, wherein the laser beam source (5) is configured to emit the pulsed laser radiation (6) with a pulse width of less than 1 ps.

4. The apparatus according to claim 1, wherein the laser beam source (5) is configured to emit the pulsed laser radiation (6) with a wavelength of 300 nm to 400 nm and a pulse frequency not exceeding 2 MHz, and the optical system focuses the pulsed laser radiation into a focal spot (13) having a maximum diameter of 2 µm or less.

5. The apparatus according to one of the preceding claims, comprising a contact glass (10) for placement on the cornea (12), wherein a contact surface of the contact glass (10) to be placed on the front surface (18) of the cornea (12) has a radius of curvature not exceeding 50 mm, preferably not exceeding 20 mm.

6. The apparatus according to any of the preceding claims, wherein the beam optics (8) have an optical field in the cornea (12) of the eye (11) with a diameter of ≥ 3 mm, in particular of ≥ 6 mm, and most preferably of ≥ 7 mm.

7. A method for isolating a lenticule (15) in the cornea (12) of an eye (11), wherein - at least one cut surface (17) is defined in the cornea (12) that delimits the lenticule (15) and does not extend at a constant distance from the anterior surface (18) of the cornea (12), - a path (19) is defined that lies along the cut surface (17), - pulsed laser radiation (6) is emitted into the cornea (12) with - a pulse frequency of 1.2 MHz to 10 MHz, - a pulse energy of 1 nJ to 200 nJ, and - a wavelength penetrating into the cornea (12), - beam optics (8) are used, which focus the pulsed laser radiation (6) into the cornea (12) at a focus (13) having a maximum diameter of less than 3 µm, and - the focus (13) is shifted within the cornea (12), wherein the focus (13) travels along the path (19), - wherein the method does not perform surgical treatment of the living human or animal eye, characterized in that - the pulse energy has a value of 10 nJ to 80 nJ and / or the beam optics (8) have a numerical aperture of at least 0.33.

8. The method according to claim 7, wherein the wavelength has a value of 1030 nm to 1060 nm.

9. The method according to claim 8, wherein the pulse duration is less than 1 ps.

10. The method according to any one of claims 7 to 8, wherein the wavelength has a value of 300 nm to 400 nm, the pulse frequency has a value not exceeding 2 MHz, and the focus has a maximum diameter of 2 µm or less.

11. The method according to any one of claims 7 to 10, wherein a contact glass (10) is placed on the eye, which has a contact surface placed on the front surface (18) of the cornea (12) with a radius of curvature not exceeding 50 mm, preferably not exceeding 20 mm.

12. The method according to any one of claims 7 to 11, wherein the beam optics (8) produce an optical field in the cornea (12) of the eye (11) with a diameter of ≥ 3 mm, in particular of ≥ 6 mm, and most preferably of ≥ 7 mm.