Therapeutic device and method for determining eye orientation

Abstract

The invention relates to a treatment device (10) and a method for determining an eye orientation of an eye (16). The treatment device (10) comprises: at least one ophthalmic laser (12) for irradiating an eye (16) with laser radiation (20); a capture device (24) having at least one camera (26), where the capture device (24) is formed to capture eye record data by means of the at least one camera (26); and a computing device (18) formed to determine an eye orientation from the eye record data, where the eye orientation comprises a distance (3D), a vertical displacement (1D) and a horizontal displacement (2D) of the eye (16) with respect to a preset reference point of the ophthalmic laser (12) and an eyeball rotation (6D), a vertical rotation (4D) and a horizontal rotation (5D) of the eye (16), wherein the computing device (18) is further formed to generate control data for controlling the treatment device (10) as a function of the determined eye orientation.

Description

Technical Field

[0001] The invention relates to a therapeutic device for treating a human or animal eye. Furthermore, the invention relates to a method for determining an eye orientation of a human or animal eye, a computer program comprising commands for causing the therapeutic device to perform the method, and a computer-readable medium on which the computer program is stored. Background Art

[0002] Therapeutic devices and methods for controlling ophthalmic lasers to correct optical visual disorders or pathological and / or unnaturally altered areas of the cornea are known in the prior art, wherein the pulsed laser and the beam focusing device can, for example, be formed such that the laser pulses achieve photodisruption and / or ablation in a focus located within the organic tissue to remove tissue, in particular tissue lenticules, from the cornea.

[0003] However, due to the displacement of the eye relative to the laser reference point, undesired effects may occur in the treatment, in particular decentration and aberrations, in particular chromatic aberrations. In order to center the eye for treatment, eye tracking systems ("eye trackers") or pupil tracking systems ("pupil trackers") are known, which can identify translational displacements of the eye to provide compensation for the displacement. However, conventional eye tracking systems cannot capture all possible causes of eye decentration, so undesired treatment effects may occur despite compensation for assumed translational displacements. SUMMARY OF THE INVENTION

[0005] It is therefore an object of the present invention to improve the capture of the eye orientation of an eye for treatment with an ophthalmic laser.

[0006] This object is solved by the independent claims. Advantageous embodiments of the invention are disclosed in the dependent claims, the following description and the drawings.

[0007] The invention is based on the idea of ​​determining the eye orientation in six dimensions, wherein in addition to the translational displacement in the x, y and z directions, the rotation of the eye in the x, y and z directions is also determined, so that the cause of decentration can be determined in an improved manner. If the eye is displaced by translation or rotation, this distinction can contribute particularly significantly to compensating for the resulting effect.

[0008] One aspect of the invention relates to a therapeutic device for treating human and / or animal eyes. The therapeutic device comprises: at least one ophthalmic laser for irradiating the eye with laser radiation; a capture device having at least one camera, wherein the capture device is configured to capture eye recording data by the at least one camera; and a computing device configured to determine an eye orientation based on the eye recording data, wherein the eye orientation comprises a distance, a vertical displacement and a horizontal displacement of the eye relative to a preset reference point of the ophthalmic laser, and an eyeball rotation, a vertical rotation and a horizontal rotation of the eye. In addition, the computing device is configured to generate control data for controlling the therapeutic device based on the determined eye orientation.

[0009] In other words, a therapeutic device configured for treating a human or animal eye may comprise at least one ophthalmic laser, in particular a photoablation and / or photodestruction laser and / or a laser for producing laser-induced refractive index changes and / or a laser for increasing corneal tissue cross-linking.

[0010] Furthermore, the treatment device may comprise at least one camera, in particular a plurality of cameras, which may be arranged in a capture device of the treatment device, wherein the camera is configured to capture eye recording data of an eye. This means that the eye recording data may comprise one or more recordings of an eye, which may be located in a treatment area at the treatment device. The eye recording data may be recorded in the optical or visible spectral range and / or in the infrared spectral range.

[0011] The computing device of the treatment device, which can in particular be formed as a computer including one or more processors, in particular microprocessors, can then evaluate the eye recording data and determine the eye orientation. Here, the eye orientation can include not only translational displacements in the x-direction (horizontal displacement), y-direction (vertical displacement) and z-direction (distance), but also rotations of the eye can be determined. On the one hand, eye rotations, i.e. rotations about the z-axis, which can in particular extend through a reference point of the laser, can be determined as rotational displacements, as well as tilts or rotations of the eye along the z-axis in the x-direction (vertical rotation) and y-direction (horizontal rotation).

[0012] In order to determine the rotational movement, a variety of strategies can be applied to evaluate the eye recording data. On the one hand, landmarks or preset structures can be identified in the eye, where if there is a displacement or decentering due to the rotation or translation of the eye, it can be distinguished due to the representation of the changes of these landmarks or preset structures in the captured eye recording data. In order to determine the landmarks, for example, a recording of an eye with a known eye orientation, in particular a diagnostic image of the eye, can be used, where the landmarks of the diagnostic image can be compared with the eye recording data of the capture device to determine the changes. In this article, circular structures have proven to be particularly suitable landmarks, such as the pupil edge or the corneal limbus (transition from the iris to the sclera) of the eye. For example, if these circular structures are represented as elliptical or oval deformations in the eye recording data, there can be a rotation. However, if the structure maintains a circular shape, but is located outside the center of the reference point, there can only be a translational displacement. Here, the reference point can be a point in or on the eye, such as the corneal vertex and / or the pupil center point. Alternatively or additionally, the reference point can also be the neutral position or zero position of the laser.

[0013] As a further strategy to determine eye orientation, the capture device may include multiple cameras that record the eye from different directions. This means that the cameras may be facing the eye at different known angles. Based on the eye recording data recorded from different directions, the rotation and / or translation of the eye can then be inferred.

[0014] As a further strategy for determining the eye orientation, it can also be provided that the treatment device, in particular the capture device, comprises a projection unit which can emit a light signal with a preset projection pattern to the eye, wherein the reflection of the projection pattern can be captured by a camera. Based on the deformation of the recorded reflection of the projection pattern, a translation and / or rotation of the eye can then be calculated.

[0015] The determined eye orientation can then be used to generate control data for controlling the treatment device or to adapt predetermined control data, in particular so that the originally planned irradiation position is adapted to the determined eye orientation. The control data may include a corresponding data set for positioning and / or focusing the individual laser pulses in the cornea. Additionally or alternatively, a corresponding 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 the laser beam of the corresponding laser may be included in the control data.

[0016] By means of the present invention, the advantage arises that better treatment results can be obtained.

[0017] The invention also includes embodiments that produce additional advantages.

[0018] In an embodiment, the capture device includes a projection unit, which is configured to illuminate a projection pattern, wherein the computing device is configured to determine the eye orientation according to the projection pattern captured in the eye recording data. For example, it can be provided that the projection pattern is a stripe pattern or a grid pattern, wherein the stripes have a preset distance between them. In other words, a previously known projection pattern can be irradiated to the eye by a projection unit (projector), wherein the reflection of the projection pattern reflected from the eye can be detected by the capture device. If a stripe pattern is used, the distance to the projection unit and therefore the distance from the eye to the reference point can be determined based on the distance between the stripes. In addition, the rotation in the horizontal and / or vertical direction can be determined by the order of the distance. For example, if the distance on one side of the projection pattern becomes larger than the distance on the other side in the reflection of the stripes, there may be a rotation. Specifically, this can be used together with a captured pupil position or a captured limbal center to determine a portion of the translation and a portion of the rotation. By this embodiment, the advantage generated is that the rotation of the eye can be determined in an improved manner.

[0019] In another embodiment, the capture device comprises at least two cameras, which are arranged to record eye recording data from different angles. This means that the capture device comprises at least two cameras, in particular more than two cameras, which are configured and arranged to record the eye from multiple directions or angles. From the volume information obtained in this way, the translation and / or rotation of the eye to a reference point can then be ascertained. For example, if the eye is eccentric in the eye recording of one camera and centered in the eye recording of another camera, the corresponding direction of the rotation to the camera can be inferred. By this embodiment, the advantage arises that the eye orientation can be determined in an improved manner, which improves the provision of control data.

[0020] Alternatively or additionally, it is provided that the camera is designed as a plenoptic camera. Plenoptic cameras, also called light field cameras, can capture, in addition to the usual 2 image dimensions, the direction of the incident light beam, from which information about the image depth can be determined. Thus, the eye orientation can be determined from the eye recording data that have been recorded by the plenoptic camera.

[0021] In another embodiment, landmarks of the eye are predetermined, wherein the computing device is configured to determine the eye orientation based on the position of the landmarks in the eye recording data. For example, the pupil center point can be used as a landmark on the one hand, by which the displacement in the horizontal and / or vertical direction can be ascertained. In addition, for example, the structure of the iris can be predetermined, thereby ascertaining the eye rotation. In addition, a circular structure in the eye, in particular the limbus, can be used as a landmark, for example, to ascertain the rotation and / or distance of the eye. Thus, a predetermined diameter of the limbus of the eye can be compared, for example, with the diameter of the limbus in the eye recording data to determine the distance of the eye from the treatment device, wherein the diameter or radius increases with decreasing distance. In order to determine the rotation in the vertical and / or horizontal direction, it can be checked whether the circular structure, in particular the limbus, has an elliptical shape in the eye recording data, wherein the rotation direction and / or the rotation angle can be provided based on the shape of the ellipse that appears. Thus, by the position of the pupil or the position of the limbus center in combination with the deformation of the limbus and / or pupil in the eye recording data, the height of the translational part of the eye and the height of the rotational part of the eye can be inferred in particular. By means of this embodiment, the advantage arises that the eye orientation can be ascertained using predetermined structures or landmarks of the eye and only one camera.

[0022] In another embodiment, the computing device is configured to monitor the centering of the eye on the contact element of the therapeutic device using the control data. This means that the process of the eye approaching the contact element can be monitored, wherein the control data can be used to output a signal if the eye is eccentric due to translation and / or rotation. In particular, if the centering corresponds to a preset centering condition both in the translation direction and in the rotation direction, the control data can be used to activate a fixation device for automatically fixing the eye.

[0023] In another embodiment, the computing device is configured to utilize the control data to adapt the irradiation position of the laser beam of the ophthalmic laser, in particular during the treatment. This means that the initially planned irradiation position can be adapted based on the current eye orientation so that the planned position is also irradiated in the case of an eccentric eye. Thereby, the treatment can be improved.

[0024] Another aspect of the invention relates to a method for determining the eye orientation of a human and / or animal eye using a treatment device with an ophthalmic laser, wherein eye recording data of the eye are captured by a capture device, the capture device comprising at least one camera, wherein the eye orientation is ascertained by a computing device from the eye recordings, wherein the distance, vertical and horizontal displacement of the eye relative to a preset reference point of the ophthalmic laser, as well as the eyeball rotation, vertical rotation and horizontal rotation of the eye are determined as the eye orientation, wherein the computing device generates control data for controlling the treatment device based on the ascertained eye orientation. Here, the same advantages and variant possibilities arise as in the treatment device.

[0025] The method may include at least one additional step, which is performed if and only if an application case or application situation occurs, which application case or application situation is not explicitly described here. For example, this step may include outputting an error message and / or outputting a request for input user feedback. Additionally or alternatively, it may be provided that a default setting and / or a predetermined initial state is adjusted.

[0026] On the other hand, it is related to a computing device or a control device, which is configured to perform the steps of at least one embodiment of one or both of the aforementioned methods. In addition, the computing device may include a computing unit for electronic data processing, such as a processor. The computing unit may include at least one microcontroller and / or at least one microprocessor. The computing unit may be configured as an integrated circuit and / or a microchip. In addition, the control device may include an (electronic) data memory or a storage unit. A program code may be stored on a data memory, by which the steps of the corresponding embodiments of the method are encoded. The program code may include control data for the corresponding laser. The program code may be executed by a computing unit, thereby causing the computing device to execute the corresponding embodiment. The computing device may be configured as a control chip or a control unit. The computing device may be included in a computer or a computer cluster, for example.

[0027] Another aspect of the invention relates to a computer program. The computer program includes, for example, commands forming a program code. The program code may include at least one control data set having corresponding control data for a corresponding laser. When the program code is executed by a computer or a computer cluster, the previously described method or at least one embodiment thereof is performed.

[0028] Another aspect of the present invention relates to a computer-readable medium (storage medium) on which the above-mentioned computer program and its commands are stored respectively. In order to execute the computer program, a computer or a computer cluster can access the computer-readable medium and read out its content. For example, the storage medium is formed as a data memory, in particular at least partially formed as a volatile or non-volatile data memory. The non-volatile data memory can be a flash memory and / or an SSD (solid state drive) and / or a hard disk. The volatile data memory can be a RAM (random access memory). For example, the command can exist as a source code of a programming language and / or as an assembler and / or as a binary code.

[0029] Further features and advantages of one of the aspects described herein may result from the embodiments of another aspect of the invention. Therefore, if the features of the embodiments of the invention are not explicitly described as mutually exclusive, they may exist in any combination with each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Below, additional features and advantages of the present invention are described in the form of advantageous implementation examples based on the accompanying drawings. The features or feature combinations of the implementation examples described below may exist in any combination in combination with each other and / or with the feature combinations of the implementation examples. This means that the features of the implementation examples may supplement and / or replace the features of the implementation examples, and vice versa. Therefore, configurations are also considered to be covered and disclosed by the present invention, which are not explicitly shown or explained in the drawings, but are produced and can be generated by separate feature combinations from the implementation examples and / or implementation examples. Therefore, configurations are also considered to be disclosed, which do not include all the features of the originally proposed claims or extend beyond or deviate from the feature combinations set forth in the relationship of the claims. For the implementation examples, it is shown:

[0031] Figure 1 is a therapeutic device according to an exemplary embodiment;

[0032] Figure 2 is a therapeutic device according to another exemplary embodiment.

[0033] Figure 3 is a therapeutic device according to another exemplary embodiment.

[0034] Figure 4 Is a representation of the eye's eye orientation.

[0035] In the figures, identical or functionally identical elements are provided with the same reference symbols. DETAILED DESCRIPTION OF THE INVENTION

[0037] Figure 1 A schematic diagram of a treatment device 10 with an ophthalmic laser 12 is shown for removing tissue 14 from a human or animal eye 16, in particular the cornea, by photodisruption and / or ablation. For example, the tissue 14 may represent a lenticule or also a volumetric body, which may be separated from the cornea of ​​the eye 16 for correction of visual disorders by the laser 12. The corrective contour or geometry of the tissue 14 to be removed may be provided by a computing device 18 or a control device, in particular in the form of control data, so that the laser 12 emits pulsed laser pulses into the cornea of ​​the eye 16 in a pattern predefined by the control data for removing the tissue 14. Alternatively, the computing device 18 may be a computing device 18 external to the treatment device 10.

[0038] also, Figure 1 It is shown that a laser beam 20 generated by laser 12 can be deflected toward eye 16 by a beam deflection device 22, such as, for example, a rotary scanner, to remove tissue 14. Beam deflection device 22 can also be controlled by computing device 18 to remove tissue 14.

[0039] The laser 12 shown may be a photodisruptive and / or photoablative laser formed to emit laser pulses having a wavelength in the range of between 300 nanometers and 1400 nanometers, for example between 700 nanometers and 1200 nanometers, with a corresponding pulse duration between 1 femtosecond and 1 nanosecond, for example between 10 femtoseconds and 10 picoseconds, and a repetition frequency of the laser pulses greater than 10 kilohertz, for example between 100 kilohertz and 100 megahertz. In addition, the computing device 18 optionally includes a storage device (not shown) for at least temporarily storing at least one control data set, wherein the one or more control data sets include control data for positioning and / or for focusing individual laser pulses in the cornea.

[0040] In order to be able to address a predetermined treatment location in the eye 16 by means of the laser beam 20, the eye orientation of the eye 16 in the reference point of the laser must correspond to the predetermined eye orientation or the eye orientation relative to the reference point must be known or determinable in order to guide the laser beam 20 to the corresponding treatment location by means of the beam deflection device 22. In order to determine the eye orientation of the eye 16, the treatment device 10 may comprise a capture device 24. In this context, it may be provided that the capture device 24 comprises at least one camera 26, which records images of the eye 16 in the visible and / or infrared spectral range and provides them to the computing device 18 as eye recording data.

[0041] Furthermore, the computing device 18 can be formed to evaluate the eye recording data and thus provide as an eye orientation a distance, a vertical displacement and a horizontal displacement of the eye 16 relative to a reference point, which can be preset by the neutral position of the beam deflection device 22. Furthermore, the computing device 18 can be formed to determine from the eye recording data an eye rotation, which means a rotation of the eye 16 about a preset axis of the laser beam 20 in the neutral position of the beam deflection device 22, as well as a vertical rotation and a horizontal rotation of the eye 16.

[0042] The eye orientation and the associated direction of the eye 16 are for example Figure 4 Here, the first dimension is provided by a horizontal displacement ID, the second dimension is provided by a vertical displacement 2D, and the third dimension is provided by a distance or lateral displacement 3D, which together provide a translational displacement of the eye 16 relative to the treatment device 10 or a reference point. In addition, a horizontal rotation 4D, a vertical rotation 5D, and an eye movement 6D can provide an overall six-dimensional orientation of the eye 16 in space, which can be determined by the computing device 18 based on the eye record.

[0043] In order to enable the computing device 18 to determine these six dimensions from the recording data, in the case of only one camera 26, the structure of the eye, in particular the landmarks of the eye, can be predetermined, wherein the structure of the eye, in particular the landmarks of the eye, can be ascertained in the eye recording. The landmarks ascertained in the eye recording, in particular the position and / or the distortion / shear, can then be compared with the position and / or the distortion / shear of the predetermined landmarks, and it can be checked whether they deviate from each other and to what extent. Through this deviation, the direction of the eye can be ascertained. In particular, the limbus can be measured in the eye recording data, for example, the radius or diameter at least in the horizontal and vertical directions. Subsequently, it can be compared with the predetermined landmarks of the limbus to determine how far the eye 16 is from the treatment device and whether there is a rotation in the horizontal or vertical direction. For example, if the radius in all spatial directions is smaller than the radius in the predetermined landmarks, the eye 16 is farther from the reference point. If there is a rotation, the radius can change in the corresponding direction, which means that the originally circular limbus is represented as an ellipse or an oval in the eye recording data. From this deformation, the rotation of the eye in the corresponding direction can be inferred.

[0044] After the computing device 18 has ascertained the eye orientation in six dimensions, the computing device 18 can generate control data for controlling the treatment device 10, wherein possible deviations from the optimized eye orientation are compensated. In particular, the control data can control the beam deflection device 22 so that the laser beam 20 is directed to the originally planned irradiation position. In particular, this can also be performed during treatment, wherein the eye orientation can be monitored in real time by the capture device 24.

[0045] exist Figure 2 , another exemplary embodiment of the therapeutic device 10 is shown. In this embodiment, the capture device 24 may include at least two cameras 26 that capture a recording of the eye 16.

[0046] Here, the camera 26 of the capture device 24 can be directed to the eye 16 at different preset angles, thereby recording the eye 16 from different positions. In particular, additional cameras with additional angles can be provided. Due to the different recording angles of the eye 16, the computing device 18 can determine depth information, by which the eye orientation in six dimensions can be ascertained.

[0047] exist Figure 3, another exemplary embodiment of a therapeutic device 10 is shown. In this embodiment, it can be provided that, in addition to the camera 26, the capture device 24 can also include a projection unit 28 for ascertaining the eye orientation, which can be formed to radiate a light pattern or a projection pattern to the eye 16. For example, the projection pattern can be a line or grid pattern with a preset distance between the lines. Based on the reflections of this projection pattern that can be captured by the camera 26, the computing device 18 can determine the distance and the vertical or horizontal rotation of the eye 16. For example, the translation and rotation can then be additionally ascertained based on landmarks in the eye 16, in particular based on the pattern of the iris of the eye 16 and / or the pupil position. In order to determine the vertical and horizontal rotation, the distance of the lines or stripe patterns can be checked here, wherein when the eye is rotated, the lines take up a greater distance in the direction of rotation.

[0048] In particular, Figures 1 to 3 The features of the embodiments described in can also be combined with each other, so that the determination of the eye orientation can be improved.

[0049] Overall, these embodiments illustrate how the present invention can determine eye orientation in six dimensions.

Claims

1. A therapeutic device (10) for treating a human or animal eye (16), include: - at least one ophthalmic laser (12) for irradiating the eye (16) with laser radiation (20); - a capture device (24) having at least one camera (26), wherein the capture device (24) is configured to capture eye registration data via the at least one camera (26); as well as - a computing device (18) configured to determine an eye orientation based on the eye recording data, wherein the eye orientation comprises a distance (3D), a vertical displacement (1D) and a horizontal displacement (2D) of the eye (16) with respect to a preset reference point of the ophthalmic laser (12) and an eyeball rotation (6D), a vertical rotation (4D) and a horizontal rotation (5D) of the eye (16), - wherein the computing device (18) is further configured to generate control data for controlling the therapeutic device (10) based on the determined eye orientation.

2. The therapeutic device (10) according to claim 1, in, The capture device (24) comprises a projection unit (18) configured to emit a projection pattern, wherein the computing device (18) is configured to determine the eye orientation based on the projection pattern captured in the eye registration data.

3. The therapeutic device (10) according to claim 2, in, The projection pattern is a stripe pattern, and there is a preset distance between the stripes.

4. The therapeutic device (10) according to any one of the preceding claims, in, The capture device (24) comprises at least two cameras (26) arranged to record the eye-recording data from different angles.

5. The therapeutic device (10) according to any one of the preceding claims, in, Landmarks of the eye (16) are predetermined, wherein the computing device (18) is configured to determine the eye orientation based on the positions of the landmarks in the eye recording data.

6. The therapeutic device (10) according to any one of the preceding claims, in, The computing device (18) is configured to use the control data to monitor the centering of the eye (16) on the contact element of the treatment device (10).

7. The therapeutic device (10) according to any one of the preceding claims, in, The computing device (24) is configured to adapt the irradiation position of the laser beam (20) of the ophthalmic laser (12) using the control data, in particular during treatment.

8. A method for determining the eye orientation of a human eye and / or an animal eye (16) of a therapeutic device (10) using an ophthalmic laser (12), wherein eye recording data of the eye (16) is captured by a capturing device (24), the capturing device (24) comprising at least one camera (26), wherein the eye orientation is determined by the computing device (18) based on the eye recording, wherein the distance (3D), vertical displacement (1D) and horizontal displacement (2D) of the eye (16) relative to a preset reference point of the ophthalmic laser (12) as well as the eyeball rotation (6D), vertical rotation (4D) and horizontal rotation (5D) of the eye (16) are determined as the eye orientation, wherein control data for controlling the therapeutic device (10) is generated by the computing device (18) based on the determined eye orientation.

9. Computer program comprising instructions causing a therapeutic device (10) to perform the method according to claim 8.

10. Computer readable medium having stored thereon a computer program according to claim 9.

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