Method for providing control data for ophthalmic laser of treatment device

Abstract

The invention relates to a device and a method for providing control data for an ophthalmic laser (12) of a treatment device (10). The method comprises: determining (S10) correction data for a planned refractive correction of a visual disorder of the cornea (16) from predetermined examination data, wherein the correction data comprises corrections of spherical, cylindrical and axial values; ascertaining (S12) adapted correction data from the column map and the ascertained correction data, the correction of the spherical and / or cylindrical and / or axial values being adapted by means of the column map to the used treatment device (10) such that the refractive correction having the adapted correction data corresponds to the planned refractive correction; wherein the column map is determined by previous treatment results using the same treatment device; and providing (S14) control data based on the adapted correction data.

Description

Technical Field

[0001] The invention relates to a method for providing control data for an ophthalmic laser of a treatment device. Furthermore, the invention relates to a control device configured to perform the method, a treatment device having such a control device, and a computer program comprising commands for causing the treatment device to perform the method. Furthermore, a computer-readable medium having the computer program stored thereon is provided. 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] When treating the cornea, it may happen that the correction achieved deviates from the planned correction. Specifically, this may be based on the characteristics of the environment in which the treatment device is located, demographics, differences in treatment or diagnosis by physicians, and / or systematic distortions of the instruments used. SUMMARY OF THE INVENTION

[0004] It is therefore an object of the present invention to provide control data for controlling an ophthalmic laser and / or a therapeutic device so as to produce an improved correction.

[0005] 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.

[0006] The invention is based on the idea of ​​creating a nomogram which includes the planned and achieved corrections, in particular sphere, cylinder and axis values. In treatment planning, the planned correction data required for the treatment can then be deduced from the nomogram based on the achieved correction data.

[0007] One aspect of the invention relates to a method for providing control data for an ophthalmic laser of a therapeutic device, wherein the method comprises the following steps performed by a control device. An apparatus or an apparatus component, in particular a computer or a processor, which can automatically or semi-automatically perform the following steps is understood as a control device.

[0008] In the method, correction data for a planned refractive correction of corneal visual disorders are determined from predetermined examination data, wherein the correction data include corrections of sphere values, cylinder values ​​and axis values. Furthermore, adapted correction data are determined based on a nomogram and the determined correction data, wherein the correction of sphere values ​​and / or cylinder values ​​and / or axis values ​​is adapted to the treatment device used by the nomogram, so that the refractive correction with the adapted correction data corresponds to the planned refractive correction, wherein the nomogram is determined by previous treatment results of the same treatment device. Finally, control data based on the adapted correction data are provided.

[0009] In other words, due to the properties of the treatment device, the achieved refractive correction may deviate from the planned refractive correction. This deviation can be compensated by the nomogram, i.e. the correction data initially determined are adapted so that the planned refractive correction is obtained as the achieved refractive correction.

[0010] At this point, initial correction data for correcting the corneal refraction can first be determined from predetermined examination data. The predetermined examination data can, for example, originate from explicit or subjective refraction measurements, in particular by means of a comprehensive refractometer. Alternatively or in addition, the examination data can include wavefront measurements and / or topographic measurements of the cornea. The refractive correction for compensating for the visual impairment can include at least sphere values, cylinder values ​​and axis values.

[0011] From the nomogram, the treatment results of these treatment devices and the originally planned corrections can be presented, and the nomogram can rely on the basis of previous treatments with similar treatment devices (e.g. the same treatment device). Then, by means of the control device, the initially planned correction data can be compared with the achieved treatment results to determine by means of the nomogram which initial correction data can be used to achieve these treatment results. This means that the initially planned sphere values ​​can be compared with the achieved sphere values ​​and the adapted sphere values ​​can be determined by means of the nomogram, and furthermore, the achieved cylinder values ​​can be determined by means of the nomogram as adapted cylinder values ​​and the axis values ​​can be determined by means of the nomogram as adapted axis values.

[0012] Finally, adapted correction data can be provided in the form of control data, which in particular comprise adapted spherical values, cylindrical values ​​and axial values, wherein the treatment device and / or the ophthalmic laser can be controlled by means of the control data.

[0013] The control data may include a corresponding data set for positioning and / or focusing the individual laser pulses in the cornea. Additionally or alternatively, the control data may include a corresponding data set for adjusting at least one beam arrangement for beam guiding and / or beam shaping and / or beam deflecting and / or beam focusing the laser beam of the individual lasers.

[0014] Specifically, the nomogram may include changes in manifest refraction, changes in ciliary muscle paralysis refraction, changes in automatic refraction, changes in aberration refraction at a fixed analysis diameter (and reference center), changes in aberration refraction at maximum pupil size, changes in corneal astigmatism refraction, or similar local anatomical indicators, with the aim of obtaining an optimized nomogram from which the adaptation values ​​for achieving refractive correction can be determined.

[0015] By means of the invention, an improved refractive correction can be achieved, since the properties of similar or identical treatment devices can be compensated.

[0016] The invention also includes embodiments that produce additional advantages.

[0017] In an embodiment, the nomogram is determined by previous treatment results of the same treatment device. This means that the nomogram is specifically tailored to the treatment device used. In particular, an own nomogram can be created for each laser of the treatment device. To this end, after a predetermined number of treatments, for example after ten treatments, the use of the nomogram can be approved, so that the initially planned correction data can be adapted. Thereby, the advantage is that the nomogram takes into account the characteristic characteristics of the treatment device used.

[0018] In another embodiment, the nomogram is automatically updated. In other words, treatment results or post-operative data can be restored to the treatment device and / or control device, in particular using artificial intelligence, to complete the nomogram and / or improve accuracy.

[0019] For example, provision is made for a temporal weighting of previous treatment results in the nomogram. In particular, provision can be made that more recent treatment results have a higher weight than older treatment results. Thus, among other things, it can be ensured that temporal changes of the laser and / or the treatment device are detected, so that improved adaptation correction data can be created.

[0020] In another embodiment, the nomogram is regenerated after a preset time period and / or after a preset number of new treatment results. Thus, it can be avoided in particular that outliers have too strong a weight in the nomogram. In addition, changes in the laser and / or the treatment device can be reacted to in an improved manner. The preset time period after which the nomogram is regenerated can, for example, depend on the season, so that environmental conditions can be taken into account in an improved manner. The preset number of times after which the nomogram is regenerated can occur, for example, after 100 or 200 treatments with the treatment device.

[0021] In another embodiment, the nomogram is based on a linear correlation between the planned refractive correction and the achieved refractive correction. This means that a regression between the planned refractive correction and the achieved refractive correction can be performed, wherein the values ​​of the adapted correction parameters can be determined by means of this linear balance function. In particular, this can be performed separately for sphere values, cylinder values ​​and axis values. In particular, the nomogram can exist in different coordinate systems:

[0022] For example, the nomogram can be provided as a sphere and a negative cylinder, where the adapted correction values ​​thus result in

[0023] S conv =S orig +C orig

[0024] C conv＝ -C orig

[0025] A conv＝ mod(A orig +90,180)

[0026] Among them, S conv is the spherical value of the fit, S orig is the spherical value of the initial plan, C orig is the cylinder surface value of the initial plan, C conv is the value of the cylinder to be fitted, A conv is the adapted axis value, A orig are the axis values ​​of the initial plan. Alternatively or additionally, the nomogram may also be represented as a sphere and a positive cylinder.

[0027] In an alternative configuration, a nomogram can be provided with the aid of spherical equivalent values ​​and astigmatism (axial values). In this case, the achieved change in spherical equivalent value can be correlated with the planned change, and the absolute magnitude of the achieved change in cylinder (vector analysis) can be correlated with the planned change. In addition, for example, the spin effect of residual astigmatism can also be taken into account.

[0028] In another alternative configuration, a nomogram can be provided based on the principal meridians. Here, the sphere values, cylinder values ​​and axis values ​​(spherocylinder values; SCA) can be converted to the principal meridians, in particular by

[0029] Cy1=S orig

[0030] Cyl2=S orig +C orig .

[0031] In another alternative configuration, a nomogram may be provided based on the cardinality and oblique astigmatism according to the Jackson Cross cylinder, wherein the sphere, cylinder and axis values ​​are represented by M, C+, Cx. In particular, other power vector notations may also be used.

[0032] For some strategies, the sphere, cylinder and axis values ​​can be expressed as M, C+, Cx, where the sign is based on mathematically independent components (vector features). In particular, it is also possible to construct a nomogram from multiple variants and select the statistically most likely variant. If the data availability is large enough, other types of nomograms can be calculated by, for example, the following distance measure between the planned correction and the correction in the database,

[0033]

[0034] Here, the most similar with the smallest distance or the owner with a distance below a tolerance can be used to create a nomogram from only that subset.

[0035] In another embodiment, a nomogram is additionally provided based on patient parameters and / or environmental parameters and / or laser parameters. This means that these parameters can be determined in the current treatment and the nomogram can be retrieved using the treatment results of the treatment in which these parameters are also present. For example, the parameters may include: the laterality, i.e. information about the right or left eye, and / or the treatment result achieved for the other eye and / or the target refraction and / or the preoperative CDVA (best corrected visual acuity, e.g. with glasses) and / or amblyopia (the value of the “bad” eye in case of severe differences between the two eyes) and / or the time after determination of the treatment result, and / or wavefront aberrations and / or UDVA (uncorrected visual acuity) and / or asphericity and / or the planned transition zone and / or the planned optical zone and / or the repetition rate of the laser and / or the duration of treatment and / or the water content of the cornea and / or the adaptability of the lens to sharpen the image and / or the age of the patient and / or the corneal curvature and / or cross-effects, for example if the sphere is treated and a cylindrical component is additionally present, and / or the patient's neuronal adaptability and / or the air humidity and / or the air pressure.

[0036] In another embodiment, the nomogram is determined based on refractive values ​​obtained in previous treatments and / or based on changes in corneal topography obtained in previous treatments. In other words, the sphere, cylinder, and axis values ​​can be determined by refractive measurements, such as subjective explicit refractive measurements performed by a phoropter, or by morphometric measurements, such as topographical measurements.

[0037] For example, provision is made for at least two nomograms to be provided, one based on refractive values ​​and the other based on local anatomical variations, wherein a range of correction data for adaptation is determined, the limit values ​​of which are provided by the respective nomogram. This means that there are at least two nomograms and the values ​​that can be provided from these nomograms can provide limit values ​​for the range in which adaptation can take place. Here, a nomogram can be provided based on the subjective refractive values ​​of the patient, while another nomogram is based on objective measurements, in particular local anatomical measurements, which indicate the curvature of the cornea. Thus, for example, a weighting can be given to whether the treatment result provides an improved subjective refraction or an improved objective refraction. In particular, it can be provided that no adaptation can be performed if the originally planned correction data are within the provided range.

[0038] In another embodiment, a warning message is generated if the deviation of the adapted correction data from the initial correction data is a preset limit value and / or if the statistical data of the nomogram of the correction data is below a threshold value. If the deviation of the adapted correction data from the initial correction data is a preset limit value, a warning message, in particular an optical and / or acoustic warning message, may be output to the user through a user interface. For example, a relative limit value may be preset, in particular 25%. Alternatively or in addition, a warning message may be generated and output if the statistical data of the nomogram is below a threshold value. This means that there is too little data in the entire nomogram to derive a statistically significant value therefrom, and / or the range of refractive correction occurring in the nomogram may have no value or too few values, thereby outputting a warning message. Therefore, at least ten treatments, for example 20, may be provided before the nomogram can be used without issuing a warning message.

[0039] Another aspect relates to a method for controlling a therapeutic device. The method comprises the method steps of at least one embodiment of the method as described above. In addition, the method for controlling a therapeutic device comprises the steps of transmitting the provided control data to at least one ophthalmic laser of the therapeutic device and controlling the therapeutic device and / or the laser using the control data.

[0040] The corresponding 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 are adjusted.

[0041] Another aspect of the present invention relates to a control device, which is formed to perform the steps of at least one embodiment of one or both of the aforementioned methods. In addition, the control device may include a computing unit, such as a processor, for electronic data processing. 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 corresponding 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 control device to perform the corresponding embodiment. The control device may be formed as a control chip or a control unit. The control device may, for example, be included in a computer or a computer cluster.

[0042] Another aspect of the invention relates to a treatment device having at least one eye surgery or ophthalmic laser and a control device, which is formed to perform the steps of at least one embodiment of one or both of the above-mentioned methods. The corresponding laser can be formed to at least partially separate a predetermined corneal volume of a human or animal eye with a predetermined interface by optical decomposition, in particular by photodisruption and / or by ablating corneal layers by means of (photo)ablation and / or achieving a laser-induced refractive index change in the cornea and / or the eye lens and / or increasing cross-linking of the cornea.

[0043] In another embodiment of the treatment device according to the invention, the laser can be suitable for emitting laser pulses with a wavelength range between 300nm and 1400nm, for example between 900nm and 1200nm, and a repetition frequency greater than 10 kilohertz (kHz), for example between 100kHz and 100 megahertz (MHz), with a corresponding pulse duration between 1fs and 1ns, for example between 10fs and 10ps. The use of such a laser in the method according to the invention also has the advantage that the irradiation of the cornea does not have to be carried out in a wavelength range below 300nm. This range is included in the term "deep ultraviolet" in laser technology. As a result, accidental damage to the cornea caused by these extremely short wavelength and high-energy beams is advantageously avoided. Photodisruptive and / or ablative lasers of the type used here usually input pulsed laser radiation with a pulse duration between 1fs and 1ns into the corneal tissue. As a result, the power density of the corresponding laser pulses required for optical breakdown can be narrowly limited spatially, so that high cutting accuracy can be achieved in the generation of the interface. In particular, the range between 700 nm and 780 nm may also be selected as the wavelength range.

[0044] In another embodiment of the therapeutic device according to the invention, the control device may include at least one storage device for at least temporarily storing at least one control data set, wherein one or more control data sets include control data for positioning and / or for focusing individual laser pulses in the cornea; and may include at least one beam device for beam guiding and / or beam shaping and / or beam deflection and / or beam focusing of the laser beam of the laser.

[0045] 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.

[0046] 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.

[0047] 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

[0048] 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:

[0049] Figure 1is a schematic diagram of a therapeutic device according to an exemplary embodiment;

[0050] Figure 2 is a schematic diagram of a method for providing control data according to an exemplary embodiment;

[0051] Figure 3 is an example graph of achieved and planned refractive correction used to provide a nomogram.

[0052] In the figures, identical or functionally identical elements are provided with the same reference symbols. DETAILED DESCRIPTION OF THE INVENTION

[0053] Figure 1 A schematic diagram of a treatment device 10 is shown with an ophthalmic laser 12 for removing tissue 14 from a human or animal cornea 16 by photodestruction and / or ablation. For example, the tissue 14 may represent a lenticule or a volume that can be separated from the cornea 16 by the ophthalmic surgical laser 12 to correct a visual disorder. The geometry of the tissue 14 to be removed may be preset by correction data, which are provided to a control device 18, in particular in the form of control data, so that the laser 12 emits pulsed laser pulses into the cornea 16 of the eye to remove the tissue 14 in accordance with a pattern predefined by the control data. Alternatively, the control device 18 may be a control device 18 that is external to the treatment device 10.

[0054] also, Figure 1 It is shown that a laser beam 20 generated by a laser 12 can be deflected toward a cornea 16 by a beam deflection device 22 (eg, a rotary scanner) to remove tissue 14. The beam deflection device 22 can also be controlled by a control device 18 to remove tissue 14.

[0055] In particular, the illustrated laser 12 may be a photodisruptive and / or photoablative laser formed to emit laser pulses having a wavelength in the range of 300 nm to 1400 nm, for example, 700 nm to 1200 nm, 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 kHz, for example, between 100 kHz and 100 MHz. In addition, the control device 18 optionally includes a storage device (not shown) for at least temporarily storing at least one control data set, wherein one or more control data sets include control data for positioning and / or for focusing individual laser pulses in the cornea.

[0056] When performing refractive correction by removing tissue 14 from cornea 16, it may happen that the planned refractive correction deviates from the achieved refractive correction. This may depend, for example, on the characteristics of the treatment device, in particular the location of treatment device 10 and / or environmental conditions. In order to take these influences into account and provide improved refractive correction control data, control device 18 may execute Figure 2 The method shown in .

[0057] In step S10, initial correction data for the planned refractive correction can be determined based on predetermined examination data, wherein the correction data include corrections for at least sphere, cylinder and axis values. The predetermined examination data can be determined from subjective measurements, for example by a phoropter, from which the corresponding sphere, cylinder and axis values ​​for the treatment can be determined.

[0058] In step S12, it can then be determined based on a predetermined nomogram how the initially determined sphere, cylinder and axis values ​​are to be adapted to achieve the originally planned refractive correction. Here, the nomogram can be adapted to the treatment device used, wherein the nomogram can provide previous treatment results with the refractive correction achieved using the treatment device 10 and the originally planned refractive correction.

[0059] For example, Figure 3 An exemplary representation of the achieved refractive correction (ordinate) and the corresponding planned refractive correction (abscissa) is shown in FIG. 1 , wherein the values ​​in the positive range at the top right may represent spherical values ​​and the values ​​in the negative range at the bottom left may represent cylindrical values. There may also be corresponding diagrams for the axial values. In particular, other symbols for the spherical values, the cylindrical values ​​and the axial values ​​may also be provided.

[0060] The provided nomogram can be automatically updated, for example, the artificial intelligence restores the treatment results or postoperative data to the treatment device 10 and / or the control device 18 and supplements or adapts the nomogram. Here, for example, due to timeliness, it can be provided that newly recorded treatment results have a higher weight in time than old treatment results. In particular, it can be provided that the nomogram is recreated after a preset time period and / or after a preset number of new treatment results. Alternatively, treatment results that exceed a preset time period can also be deleted from the previous nomogram so that the nomogram is always kept up to date.

[0061] In particular, it can also be provided that based on a nomogram of achieved refractive values ​​determined by a subjective measuring method, a second nomogram is additionally provided, which is determined by an objective measuring method, in particular a morphometric method. Then, a correction range with the limit values ​​provided by the corresponding nomogram can be determined therefrom.

[0062] The initially determined correction data can then be adapted according to the nomogram, wherein the adapted correction data can be provided to the control device 18 in the form of control data for controlling the laser 12 and / or the beam deflection device 22 in step S14. This means that the control data can be used to control the treatment device 10 for refractive correction of visual disorders.

[0063] For example, it may be provided that a warning message is generated if the adapted correction data deviate from the initial correction data by a preset value and / or the statistical data of the nomogram (ie the captured treatment values) is below a threshold value.

[0064] In general, these embodiments demonstrate how to achieve automatic provision of a nomogram.

Claims

1. A method for providing control data for an ophthalmic laser (12) of a treatment device (10), wherein the method comprises the following steps performed by a control device (18): - determining (S10) correction data for a planned refractive correction of a visual disorder of the cornea (16) based on predetermined examination data, wherein the correction data comprises corrections of sphere values, cylinder values ​​and axis values; - determining (S12) adapted correction data based on a nomogram and determined correction data, wherein the correction of the sphere value and / or the cylinder value and / or the axis value is adapted to the used treatment device (10) by means of the nomogram, so that the refractive correction with the adapted correction data corresponds to the planned refractive correction, wherein the nomogram is determined by previous treatment results using the same treatment device; - providing (S14) control data based on said adapted correction data.

2. The method according to claim 1, wherein: The nomogram is determined from previous treatment results using the same treatment device (10).

3. A method according to any one of the preceding claims, wherein: The nomogram is automatically updated.

4. The method according to claim 3, wherein: Prior treatment outcomes were time-weighted in the nomogram.

5. The method according to any one of claims 3 or 4, wherein: The nomogram is newly generated after a preset period of time and / or after a preset number of new treatment results.

6. A method according to any one of the preceding claims, wherein: The nomogram is based on a linear correlation between the planned refractive correction and the achieved refractive correction.

7. A method according to any one of the preceding claims, wherein: The nomogram is also provided as a function of patient parameters and / or environmental parameters and / or laser parameters.

8. A method according to any one of the preceding claims, wherein: The nomogram is determined based on refractive values ​​achieved in previous treatments and / or based on local anatomical changes of the cornea achieved in previous treatments.

9. The method according to claim 8, wherein: At least two nomograms are provided, one nomogram being based on the refractive values ​​and the other nomogram being based on the local anatomical changes, wherein the adapted correction data range is determined using limit values ​​provided by the respective nomograms.

10. The method according to any one of the preceding claims, wherein: If the deviation of the adapted corrected data from the initial corrected data reaches a preset limit value and / or if the statistical data of the nomogram of the corrected data is below a threshold value, a warning message is generated.

11. A control device (18) configured to perform a method according to any of the preceding claims.

12. A therapeutic device (10) comprising: at least one eye surgery laser (12) for separating a corneal volume (14) with a predefined interface of a human or animal eye by optical breakdown, in particular by photodestruction and / or photoablation, and at least one control device (18) according to claim 11.

13. Computer program comprising commands causing a therapeutic device (10) according to claim 12 to perform a method according to any one of claims 1 to 10.

14. Computer readable medium having stored thereon a computer program according to claim 13.

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