Method and device for monitoring a processing method

Abstract

The invention relates to a method and a device for monitoring a processing method, wherein the processing method is a method for processing biological tissue. An expected course of the processing method is first simulated by means of a simulation model and then, while the processing method is being carried out, the actual course is compared with the simulated course and, in the event of a deviation, a corresponding signal is output.

Description

[0001] Method and device for monitoring a machining process

[0002] The invention relates to a method and a device for monitoring a processing process, wherein the processing process is a process for processing biological tissue. First, an expected course of the processing process is simulated using a simulation model, and then, during the execution of the processing process, the actual course is compared with the simulated course, and in the event of a deviation, a corresponding signal is output.

[0003] Methods for manipulating biological tissue can be used both in vivo and in vitro. A typical in vivo method is the treatment of tumors. Some tumor treatments involve introducing current and voltage into the tissue via one or more needle-shaped electrodes, thereby destroying the tumor. Examples include microwave ablation (an electric field is applied to the tissue, resulting in thermal tissue destruction) and irreversible membrane pore therapy (IRE) (an electric field is applied to the cell membranes, creating a voltage so high that they permanently open and the cells die). In both cases, imaging (CT, MRI) is typically used for diagnostic purposes prior to treatment, and at least one needle is usually placed in or on the tumor under imaging guidance.Particularly due to the inhomogeneity of the tissue, tumor areas may not be adequately treated, allowing the tumor to continue growing. This is typically only detected several days after the intervention during a follow-up examination.

[0004] To prevent such situations and, for example, to be able to determine whether sufficient / complete tumor ablation has been achieved, intra-interventional quality control (QC) should be performed. The ablated tissue is typically determined several days after the procedure using imaging techniques with good soft tissue contrast, typically MRI. During the intervention, relatively simple quality control methods are sometimes employed. One indicator of the supposedly ablated area is the energy delivered to the tissue to date. This is determined by the time integral of the delivered power. Simple, localized temperature measurements are also used to obtain a rough estimate of the ablated area's size. Furthermore, there are methods that use ultrasound to assess the size of the ablated area during the intervention.There are also methods and devices that use changes in the impedance of the treated tissue to infer treatment success. For examples, see Philip E. Eggers, "Apparatus and Method for Characterization and Treatment of Tumors," US 005 630426 A.

[0005] The object of the present invention is to provide a method and a device for monitoring a machining process that enables more accurate monitoring of the progress and / or success of the machining process.

[0006] This problem is solved by the method for monitoring a machining process according to claim 1 and the device for the monitored execution of a machining process according to claim 23.

[0007] The invention provides a method for monitoring a processing process. The processing process is a method for processing biological tissue. The processing process can be an in vivo or an in vitro processing process. In both cases, the processing process can advantageously be monitored using the method according to the invention. If the monitored processing process is an in vitro processing process, it is not performed on the human or animal body, but on separated biological tissue. If the processing process is an in vivo processing process, it can be performed on the human or animal body. However, in both cases, the method according to the invention does not need to be performed on the human or animal body, since it only concerns the monitoring of the processing process and not the processing itself.If the method employs additional elements such as electrodes, these can also be arranged in vivo without surgical intervention. The method according to the invention is therefore not itself a method for the surgical treatment of the human or animal body, but merely a method that can be advantageously used in conjunction with the execution of a surgical procedure. A typical in vitro procedure that can be monitored using the method according to the invention is, for example, tumor removal. Biological tissue is advantageously understood here to mean material composed of biological cells.

[0008] According to the invention, an expected progression of the machining process is first simulated using a simulation model. The expected progression of the machining process is, in particular, a temporal progression (time history). This simulation can advantageously be computer-implemented. For this purpose, a computer program can be executed on a computer that causes the computer to perform the simulation. According to the invention, this simulation predicts an expected progression of the values ​​of at least one parameter during the machining process. The expected progression of the values ​​of the at least one parameter is, in particular, a temporal progression (time history).After the simulation has been executed and the expected course of values ​​for at least one parameter has been predetermined, the actual course of values ​​for this parameter is measured and / or calculated from measurements during the execution of the processing procedure. The actual course of values ​​for this parameter is, in particular, a time course. Advantageously, the at least one parameter is a parameter that influences the processing procedure and / or arises automatically during the execution of the processing procedure. For example, if the processing procedure is the ablation of biological tissue using electricity, the at least one parameter can be an impedance that occurs at the electrodes used for ablation.Advantageously, at least one parameter in an apparatus for carrying out the processing method is measurable and / or determinable without requiring any separate intervention on the biological tissue for the monitoring according to the invention. In this way, the method according to the invention can be carried out without influencing the execution of the processing method itself or having to change its sequence. Advantageously, the method according to the invention can therefore be carried out in such a way that the processing method is neither altered nor influenced by the monitoring method according to the invention. The processing method itself can thus be carried out, with the monitoring method according to the invention optionally providing information only after completion as to whether the processing method proceeded as planned.However, the procedure can also be advantageously used to interrupt or modify the processing process if it turns out that it is not proceeding as planned.

[0009] According to the invention, during the execution of the processing method, the actual progression of values ​​of at least one parameter is measured and / or calculated from measurements. Advantageously, this measurement is performed in a device or apparatus used to execute the processing method; thus, the measurement does not need to be performed on the biological tissue itself. If the progression of values ​​of the at least one parameter is calculated from measurements, this measurement can, in turn, be computer-implemented.

[0010] According to the invention, the actual behavior is then compared with the expected behavior of the values ​​of the corresponding parameter. Advantageously, this comparison can again be computer-implemented; that is, a computer can be programmed by means of a computer program to read and compare the values.

[0011] If the comparison reveals that the deviation between the actual and expected behavior exceeds a predetermined threshold, a comparison signal is output according to the invention, indicating that the machining process is not proceeding as intended. It is not strictly necessary to terminate or modify the machining process based on this comparison signal, which would often be very difficult in practice; however, this is advantageously possible. The comparison signal can also be referred to as a deviation signal.

[0012] In an advantageous embodiment, the method according to the invention can be a method for monitoring the removal and / or destruction of a tumor. In this case, the invention does not relate to the removal and / or destruction of the tumor itself, but merely to the monitoring of this process. Therefore, even in this case, the method according to the invention is not itself a surgical procedure, but merely a method used in connection with carrying out a surgical procedure.

[0013] In this case, the expected course of the processing procedure is first simulated using the simulation model, thereby predicting the expected course of values ​​of at least one parameter during the removal and / or destruction of the tumor. As described, this step can advantageously be computer-implemented. In this embodiment, the processing procedure is thus the method for removing, ablating, and / or destroying the tumor. Analogously, the method according to the invention can be used if the processing procedure is generally a method for ablating tissue. In both cases, the aim is to destroy the corresponding tissue, for example, by temperature or tension, whereby, normally, the actual volume of the tissue can remain (i.e., the tissue is not removed by the processing procedure).Normally, the damaged tissue is broken down over time by the body's own processes. Therefore, it is usually not a matter of removing tissue, but rather of inactivating or killing it (for example, through physical means).

[0014] After the simulation is executed, the actual value profile of at least one parameter is measured and / or calculated from measurements during the removal and / or destruction process. The actual profile is then compared with the expected profile of the corresponding parameter's values, as described. If the comparison reveals that the deviation between the actual and expected profiles exceeds a predefined threshold, a comparison signal is output, indicating that the removal and / or destruction is not proceeding as intended. The term "destruction" can be used here as an alternative to the term "destroyment."

[0015] At least one of the parameters can be an electrical parameter (such as impedance, an imaginary part of an impedance, permeability, and / or permittivity), a change in an electrical parameter, a spectral parameter (such as transmission, absorption, and / or fluorescence), a change in a spectral parameter, a thermal parameter (such as temperature, thermal conductivity, and / or specific heat), and / or a change in a thermal parameter. The parameter can relate in particular to a property of the biological tissue and / or a tracer (preferably introduced into the tissue).Advantageously, at least one of the parameters can be an impedance, an impedance change, an imaginary part of an impedance, an imaginary part of an impedance change, a temperature, a temperature change, a fluorescence change (e.g., of a tracer), tissue permeability and / or tracer permeability, and / or tissue permittivity and / or tracer permittivity. The impedance can include permeability as a subset of the modality. If the parameter is an impedance, complex quantities, i.e., two dimensions, can be advantageously measured. The imaginary part of the impedance or impedance change is a useful parameter because the thermal destruction of cells leads to the destruction of cell walls, which alters the capacitive coupling within the cell. This causes the imaginary part of the impedance to change irreversibly.

[0016] Advantageously, the treatment involves the thermal destruction of tissue, such as a tumor. Thermal destruction can be advantageously achieved using microwaves. Alternatively, the destruction of biological tissue can also be carried out electrically. In this case, an applied voltage irreversibly opens the ion channels of the cells, causing the cell to die. Thermal and electrical destruction result in different parameter profiles; for example, in thermal destruction, the imaginary part of the impedance changes irreversibly due to the destruction of the cell walls.

[0017] During thermal treatment of tissue, the time course is determined, among other things, by the heat propagation within the tissue. In this way, the change in parameter values ​​can reflect the progress of the processing.

[0018] Advantageously, the method according to the invention can be implemented multidimensionally, meaning that several sensors, for example electrodes, and / or several measurement paths can be used. This is particularly advantageous when the method includes several electrodes and / or several paths for current through the tissue to be processed. In this case, ratios of the individual measurement paths in the simulation and the actual measurement can advantageously be calculated before the comparison step, and only then can the comparison signal be derived from these ratios. In this case, the comparison signal or parameter can thus be considered as calculated from measurements. Advantageously, several spatially and / or temporally separated measurement points (i.e., points in spacetime) or their derivatives can be compared and / or calculated using a suitable analytical function.This includes in particular: exceeding a minimum / maximum of at least one value, falling below a minimum / maximum of at least one value, a point in time at which a certain value is reached, a slope (nth derivative), an integral, exceeding or falling below a time offset with respect to passing marker values ​​between two measuring points (for example, if heat spreads faster or slower than expected), or similar.

[0019] Advantageously, to compare the actual behavior with the expected behavior, the following can be compared: an occurrence, a point in time, and / or a trend of at least one feature, where the feature can be a feature of the trend and / or a gradient of the trend and / or an nth derivative of the trend, with n greater than or equal to 1, and / or an integral over at least a part of the trend. Thus, it is not necessary, although possible, to compare the individual values ​​of the corresponding parameter with each other; rather, specific features of the parameter's trend can be advantageously compared.

[0020] Advantageously, at least one feature can be a discontinuity, a maximum, a minimum, a saddle point, an exceedance of a minimum value, and / or a time at which a predetermined value is reached, an exceedance of a maximum value and / or an attainment of a predetermined value, an exceedance and / or fall below a time offset with respect to the passage of at least one marker value between two measuring points, and the like.

[0021] When comparing the actual trend with the expected trend, the respective values ​​of at least one parameter and / or the characteristic being compared can be compared at one, several, or all of the considered time points. A comparison of several or all considered time points is particularly advantageous, as it allows deviations not (only) from a fixed target value or a spatial target distribution, but especially from expected changes over time. Based on the expected trend, a target interval (corridor) can be defined that meets the condition that the deviation between the actual trend and the expected trend is no greater than the predefined threshold. The predefined threshold can be fixed or time-dependent.

[0022] In an advantageous embodiment of the method according to the invention, a difference and / or a quotient between the values ​​of the actual and expected courses and / or the corresponding values ​​calculated from these can be calculated to compare the actual course with the expected course. For example, the following can be calculated: for one, several, or all of the time points considered, the corresponding value of the actual course minus the corresponding value of the expected course at the corresponding time point; the values ​​of the expected course minus the value of the actual course at the corresponding time point; the value of the actual course divided by the value of the expected course at the corresponding time point; and / or the value of the expected course divided by the value of the actual course at the corresponding time point.

[0023] Advantageously, the simulation model can be a finite element model in which an object or body on which the machining process is performed, and advantageously also any equipment used for this purpose, are modeled using finite elements. Such a finite element model is preferably computer-implemented. The simulation model can additionally or alternatively be an analytical model that models an object or body on which the machining process is performed, and advantageously also any equipment used for this purpose. Alternatively or additionally, the simulation model can also be a deep learning and / or artificial intelligence model in which an object or body on which the machining process is performed, and advantageously also any equipment used for this purpose, are modeled. All these models can advantageously be computer-implemented.They can then exist in the form of computer programs that are executed on a computer.

[0024] The temporal evolution of the parameter and / or feature values ​​is determined, among other things, by the heat propagation during thermal treatment of the tissue. Advantageously, the modeling according to the invention includes thermal modeling, preferably modeling of heat propagation within the tissue.

[0025] Advantageously, energy input and / or heat propagation on the one hand, and impedance changes on the other, are simulated separately. It is particularly advantageous to first simulate energy input and / or heat propagation, and then to simulate and / or derive the change in impedance and / or other parameters from the results of the energy input or heat propagation simulation. In this way, the first simulation of energy input or heat propagation simulates which areas of the tissue heat up and how, and then simulates how the resulting temperature change alters the values ​​of the corresponding parameters. The Arrhenius equation, for example, can be used for this purpose.

[0026] Advantageously, according to the invention, the heat propagation and the resulting temperature change are simulated in a time-dependent and coupled manner, and the resulting material changes and electrical properties are simulated. From these, the characteristics of the considered value changes of the considered parameters can then be derived.

[0027] In an advantageous embodiment, the simulation of the expected course of the processing process can thus, in a first step, comprise a simulation of the propagation of heat introduced into the tissue for the purpose of destroying the tissue and a resulting temperature change, and the simulation process can then, in a second step, which is preferably carried out after the first step, comprise a simulation of the expected course of the values ​​of at least one parameter based on the simulation in the first step.

[0028] The method according to the invention is particularly advantageous when the processing method is one in which energy is introduced into an object or body by means of at least one probe. This probe can include at least one sensor for measuring the values ​​of the corresponding parameter. Advantageously, at least one of the sensors can be an electrode via which an alternating voltage can be applied to at least one area of ​​the object or body. The alternating voltage can also advantageously serve to introduce the energy into the object or body.

[0029] In an advantageous embodiment of the invention, an alternating voltage can be applied to at least one area of ​​the object or body to be treated via a plurality of electrodes to measure the values ​​of at least one parameter. It is particularly advantageous that at least one of the electrodes can be arranged on a surface of the object or body, preferably in contact with it. In this way, the number of measurement paths can be increased, even if, for example, fewer electrodes are arranged on a probe itself.

[0030] Advantageously, the alternating voltage can be applied between any two electrodes, preferably between exactly two electrodes simultaneously. Preferably, the alternating voltage can be applied between different electrodes at different times. Thus, the alternating voltage can be applied between different pairs of electrodes at different times and, in particular, can be switched sequentially between different pairs of electrodes. Considering a sequence in which the electrodes are switched sequentially, this sequence can advantageously be repeated one or more times, enabling periodic monitoring over an extended period using multiple measurement paths.

[0031] In the previous example, different measurement paths were achieved by applying the alternating voltage at different times. Alternatively or additionally, different measurement paths can also be achieved by applying an alternating voltage with a first frequency between at least two of the first electrodes and an alternating voltage with a second frequency different from the first between at least two of the second electrodes, at least one of which is not one of the first electrodes. The measurements are therefore distinguishable from one another by the frequency of the alternating voltage. It is particularly advantageous if none of the second electrodes is simultaneously one of the first electrodes, as this results in the largest possible number of measurement paths. However, it can also be advantageous to use only one first electrode and a plurality of second electrodes.For example, in this case, the first electrode can also be an electrode located outside the object or body on its surface. Using different frequencies, separate measurement paths can then be established from the first electrode to each of the other two electrodes.

[0032] The measured signals can be considered frequency-multiplexed. The measured values ​​for the individual measurement paths can be extracted from this by filtering out the parameter values ​​for the corresponding frequency of the respective measurement path.

[0033] In an advantageous embodiment, voltages can be applied between at least two first electrodes that are phase-space separated from voltages applied between at least two second electrodes, wherein advantageously at least one of the at least two second electrodes is not one of the first electrodes. A plurality of measurement paths can also be realized in this way.

[0034] Alternatively or additionally, voltages can advantageously be applied between at least two of the first electrodes in different spatial regions than between at least two of the second electrodes, wherein advantageously at least one of the at least two second electrodes is not one of the first electrodes. In this way, the measurement paths can be implemented in a spatially separated manner.

[0035] Alternatively or additionally, it is also possible to actively shield voltages between at least two of the electrodes from other electrodes, for example by active electrical isolation, such as by an opposing field.

[0036] If multiple electrodes are required, they can advantageously be arranged as an array on one, two, or more than two probes. The probes can advantageously be probes used to perform the procedure. Such probes could, for example, be ablation needles. If the probes are elongated, the array can be a one-dimensional array, i.e., an arrangement in which the electrodes are positioned side by side in one direction, with adjacent electrodes having the same distances from each other along the entire length of the array (i.e., the electrodes are equidistant) or following a predetermined function. An equidistant arrangement of the electrodes is particularly advantageous here.

[0037] In an advantageous embodiment of the invention, the simulation using the simulation model can predict the course of the values ​​of at least one parameter using at least one tissue parameter and / or at least one treatment parameter and / or at least one sensor or electrode geometry. This ensures that the simulation predicts the course more precisely, so that observed deviations are more likely to result from an unintended course of the processing procedure than from an inadequate simulation.

[0038] If the procedure is carried out as described using several electrodes, these can advantageously be interconnected in a Schlumberger / Wenner configuration.

[0039] A relative and absolute change in amplitude between different electrode pairs, the slope of this change, the asymptotic desired course, and a time interval between a constant value and an increase or decrease reflect the heat propagation and are therefore advantageous features for comparison with the simulation.

[0040] A relative and absolute change in phase between different electrode pairs, the slope of this change, the asymptotic target curve, and the time interval between a constant value and an increase or decrease reflect the extent of tissue alteration (coagulation) and are therefore advantageous features for comparison with the simulation. The comparison between amplitude and phase features allows for the separation of reversible and irreversible temperature effects and is therefore a relevant feature for comparison with the simulation.

[0041] The thermal conductivity of tissue can be advantageously approximated by its cooling behavior if the energy input during the ablation procedure is timed or variable in power. For example, energy can be introduced into the tissue for one second, leading to a temporary temperature increase. As the temperature of the heated tissue equalizes with the surrounding tissue (which maintains a constant core body temperature of approximately 37°C), the heated tissue cools down again. The heating and cooling process results in corresponding changes in the tissue's impedance due to the temperature effect described above. These changes can then be used to approximate the tissue's thermal conductivity.

[0042] Individual or combined observables can be advantageously used alone or in conjunction with a simulation model to determine the morphology of the tissue or tumor, as well as the extent of the coagulation zone over time and space. When energy is introduced into the tissue, e.g., microwaves, the observables change from state A to state B. The changes in the observables between these states can be used to determine the temporal and spatial variations in temperature and the state of coagulation. Comparing the changes between the measured states with the changes in the same states in a simulation model allows for monitoring the success of the ablation therapy. If the absolute values ​​and / or the changes in the observables between states A and B correspond sufficiently, the ablation therapy is proceeding as expected.These changes are evaluated, for example, by calculating the difference between the observables and the model.

[0043] Regarding the simulation, the following features are advantageous: • the various effects can be performed iteratively in small steps (since they are actually coupled).

[0044] • Backscatter or other measured effects that may influence the input power must be taken into account.

[0045] The complex iterative calculation presented here can also be partially simplified by using a simplified, possibly static, possibly homogeneous model. For example, the model could assume a constant absorption distribution of the input power, or it could be modeled using a linear function that calculates the absorption as a function of the distance from the source.

[0046] Advantageously, the simulation model can be updated based on a comparison of the actual process with the expected process, thereby reducing the deviation between the two. This adjustment of the simulation model is particularly useful when, for example, deviations in geometry exist between the geometry assumed during the simulation and the actual geometry during the machining process. Similarly, if machining parameters change during the execution of the process compared to the assumptions made at the time of the simulation, updating the simulation model in this way can be beneficial.

[0047] Advantageously, the simulation model will be updated using differences and / or quotients between the values ​​of the actual trend and the values ​​of the expected trend (which can be calculated as described above), so that the expected values ​​have a smaller difference to the actual values ​​or the quotients are closer to one.

[0048] Advantageously, the processing method can be controlled and / or regulated based on a comparison of the actual process with the corresponding expected process. This is particularly advantageous when the process is carried out in vitro. In this case, the output of the comparison signal can be used to modify the further course of the processing method. The goal of this modification can be, in particular, to ensure that the course of the processing method corresponds more closely to the planned course resulting from the simulation.

[0049] Advantageously, a comparison of the actual course of events with the expected course of the values ​​of the corresponding parameter can be used to determine at least one property of a processed object or body, such as coagulation, clotting, denaturation of protein-based cell components, and / or cell integrity. Such properties can provide information about the success of the processing procedure.

[0050] Preferably, the machining process is planned in advance using the simulation model. In this way, the simulated process advantageously corresponds to the process actually carried out during machining, so that deviations between the actual and expected process are more likely to indicate that the machining process is not proceeding as planned.

[0051] The indication that the processing procedure is not proceeding as intended, for example the comparison signal, can advantageously include an indication of whether over- or under-processing is occurring.

[0052] The invention also provides a device for the supervised execution of a machining process. Advantageously, the invention also provides a device for monitoring the execution of a machining process, which differs from the aforementioned device in that it does not itself comprise a machining device for carrying out the machining process. Unless otherwise stated, the term "device" shall be understood to mean both cases in the following.

[0053] The processing method is also a method for processing biological tissue. According to the invention, the device comprises at least one simulation system configured to simulate an expected course of the processing process using a simulation model and thereby predict the expected course of values ​​of at least one parameter during the processing process. The simulation system can advantageously be a programmable logic module and / or a computer or part thereof.

[0054] The device for supervised execution of the machining process also includes a machining device configured to execute the machining process. The device for monitoring the machining process does not include this machining device.

[0055] The device also has a sensor that is set up to measure the actual progression of values ​​of at least one parameter during the execution of the machining process.

[0056] Furthermore, the device includes a comparison device configured to compare the actual behavior with the expected behavior of the values ​​of the corresponding parameter and, if a deviation between the actual behavior and the expected behavior exceeds a predetermined threshold, to output a comparison signal indicating that the machining process is not proceeding as intended. The comparison device can, in turn, be a programmable logic controller (PLC) or computer, or part thereof, particularly one that also contains the simulation system.

[0057] In a particularly advantageous embodiment, the processing device can include at least one ablation needle for tumor removal. Additionally or alternatively, the at least one sensor can include at least one electrode, preferably at least two electrodes. These electrodes can advantageously be arranged on the ablation needle, or, in the case of multiple electrodes, advantageously as an array.

[0058] In an advantageous embodiment of the device, at least one of the at least one sensors can also be a temperature sensor. Such a temperature sensor can particularly preferably comprise or be a fiber Bragg grating. Preferably, at least two temperature sensors are provided. Advantageously, the device is configured to carry out a method for monitoring a machining process as described above. The features described therein can be implemented accordingly as device features in the device according to the invention.

[0059] According to the invention, a simulation model is used as described, which can, for example, be based on a finite element model. Alternatively, an empirically driven model can also be used for the simulation, for example, using empirical data.

[0060] The simulation model can be used, for example, to model tissue coagulation, such as by using the Arrhenius equation. Furthermore, it can advantageously take into account specific energy absorption in the tissue by the ablation system.

[0061] For simulation, a database containing tissue parameters, treatment parameters, and electrode geometry can be used, which can also be part of the device according to the invention.

[0062] In an advantageous embodiment, electrical measuring electrodes, acting as sensors, can be injected into the same puncture channel together with a needle probe. The measuring electrodes can, for example, be integrated into the treatment electrodes, or they can be arranged on or attached to such a needle probe in addition to the treatment electrodes.

[0063] Optionally, additional measuring electrodes can be inserted into an object as sensors alongside such an ablation needle in order to reconstruct more spatial information from the complex impedance values. This embodiment is particularly advantageous for in vitro processing.

[0064] In an advantageous embodiment of the method, complex impedances at different frequencies between the measuring electrodes can be determined in a time-dependent manner, for example by multiplexing (where all electrodes can be connected to the measuring system via one or more switches and / or determined by using multiple measuring channels).

[0065] The device according to the invention can advantageously have a graphical user interface which has a display unit on which the processing progress can be seen.

[0066] A graphical, acoustic or other warning signal can be issued as a comparison signal, for example.

[0067] Advantageously, the method can also include imaging or visualization of the measured values ​​over time. In particular, delta values ​​can be output, representing the difference or quotient between the actual and expected trends.

[0068] In a graphical representation, measurement and / or simulation values ​​can also be superimposed on (DICOM) image data. In imaging, the procedure can also include displaying areas on the object or body being treated where over- or under-treatment is present. Advantageously, the comparison signal can also be an image signal that indicates locations on the object or body being treated where there is a deviation from the expected course.

[0069] Optionally, evaluation electronics can be integrated into each electrode. Measured values ​​and / or simulation values ​​can optionally be used to control machining process parameters. Advantageously, measured values ​​and / or simulation values ​​can also be used to position machining elements, such as needle probes, for executing the machining process.

[0070] Preferably, the measurement method can be initially calibrated. Optionally, a progression of the measured values ​​during the processing process can be recorded. In an advantageous embodiment, the method can also include the determination of a fabric composition (in particular the moisture content) from, for example, impedance values. The method and the device according to the invention can also be implemented using optical measurement technology. The parameter can be one or more temperatures. In this case, the sensors can therefore be temperature sensors. Fiber Bragg grating fibers are particularly advantageous as temperature sensors. Such a thermal measurement system advantageously has known thermal transitions between at least two of the temperatures, which can be defined, for example, in a reference scenario such as a water bath.Such temperature sensors can, for example, be injected into the same puncture channel as the needle probe when using a needle probe, and / or be integrated into treatment electrodes. These temperature sensors can, for instance, be positioned on or attached to such a needle probe. Advantageously, the temperatures can be read continuously or quasi-continuously at a multitude of time points. The comparison of the actual temperature profile with the expected profile can also be advantageously performed over time, and the comparison signal can be output if a threshold value is exceeded due to the deviation.

[0071] Advantageously, optical fibers equipped with fiber Bragg gratings can be used as temperature sensors, with which at least one temperature and / or at least one temperature gradient and / or at least one heat flux can be determined. Advantageously, such a fiber Bragg grating can be read out spectrally. If the fiber Bragg grating is advantageously integrated into a needle probe, a defined thermal resistance can be generated, since the geometry and materials are known. Advantageously, this thermal resistance can be determined from the measured temperature gradient to calculate the heat flux.

[0072] The simulation can advantageously take into account changes in the spectral tissue properties, i.e., transmission, absorption and / or fluorescence.

[0073] Advantageously measured parameters include, for example, changes in the spectral properties of the tissue (transmission, absorption, fluorescence). The fiber Bragg grating can be integrated into an optical fiber (single-core or multi-core) and connected to a spectral analysis unit.

[0074] The invention will now be explained by way of example with reference to several figures. Identical reference numerals denote identical or corresponding features. The features described in the examples can also be implemented independently of the specific example and can be combined between the examples.

[0075] It shows:

[0076] Fig. 1 shows a device according to the invention for the supervised execution of a machining process,

[0077] Fig. 2 shows another example of a device according to the invention,

[0078] Fig. 3 Examples of an expected course and an actual course in a method according to the invention for monitoring a processing process that is carried out in vitro,

[0079] Fig. 4 shows a schematic setup of a device for carrying out a method according to the invention in vitro,

[0080] Fig. 5 shows an example of a planning phase for preparing a machining process that can be monitored by the method according to the invention.

[0081] Fig. 6 shows an example of a simulation in several steps,

[0082] Fig. 7 Magnitude and phase of measured impedances,

[0083] Fig. 8 shows an example of the propagation of field lines in an ablation needle with multiple electrodes, and

[0084] Fig. 9 shows the signal waveform of the magnitude of the electrical impedance during a process.

[0085] Fig. 1 schematically shows a device according to the invention for the supervised execution of a processing method. The processing method is a method for processing biological tissue, in the example shown, a tumor 3. The processing method is a method for destroying or ablating the tumor tissue 3. The method is carried out using an ablation electrode 4, which is inserted into the tumor tissue. A plurality of electrodes 5 are arranged on the ablation needle 4, through which currents can be conducted through the surrounding tissue. An alternating voltage can be applied to the electrodes 5. In this way, for example, the impedance of the ablation needle can be used as a parameter.

[0086] 4 surrounding tissue. The device shown in Fig. 1 also has a simulation system 1 which is set up to simulate an expected course of the machining process using a simulation model and thereby to determine in advance an expected course of values ​​of at least one parameter, in the example shown the impedance Zs, during the course of the machining process.

[0087] The device also includes a comparison device 2, which is configured to compare the actual course of the parameter values, i.e., the impedance Zs, with the expected course of the values. If a deviation between the actual course and the expected course is greater than a predefined threshold, a comparison signal is output, here via a corresponding output device 6. If no deviation greater than the threshold is observed during the process, a signal can optionally be output at 7 indicating that the processing was completed successfully.

[0088] In the example shown, the comparison device 2 receives, on the one hand, the values ​​of the actual course 8 from the measuring system, i.e., the electrodes.

[0089] The device uses two components: 5 as sensors, and secondly, the results from the simulation system 1 to perform the comparison. In the example shown, the simulation is based on data 9 from a preliminary planning phase, which may include, for example, the location of the processing, duration, and / or power. Fig. 2 shows an example of a device according to the invention, in which the processing method is carried out using two ablation electrodes 4a and 4b. The ablation electrodes 4a and 4b each have a plurality of measuring electrodes 5a and 5b, respectively, as sensors. Each of the ablation electrodes 4a and 4b has a multiplexer 22a and 22b, respectively, via which the respective electrodes 5a and 5b can be addressed individually. In this way, different measurement paths can be switched between the electrodes 5a and 5b, so that values ​​of the parameter can be determined from different regions.Different measuring paths can be output to an impedance analysis device 21 via a switching device 23. The impedance analysis device 21 is configured, firstly, to output an input signal TX, which is output via the switching device 23 to the multiplexers 22a and 22b. Secondly, the impedance analysis device is configured to receive signals from the multiplexers 22a and 22b via the switching device 23.

[0090] In the example shown, the impedance analysis device 21 is connected to a computer 24, which receives data from the impedance analysis device 21 in order to compare it, for example, with an expected course of the process. The computer 24 can therefore, in particular, contain the comparison device 2. Furthermore, the computer 24 can also be used to specify how the individual electrodes 5a and 5b are interconnected, i.e., in particular the temporal sequence of the interconnection and / or the frequencies with which the electrodes 5a and 5b are subjected.

[0091] Figure 3 shows exemplary measurement results and simulations of parameters obtained using an ablation antenna 4 during the processing of an object 3 in an in vitro situation. The object 3 is a biological tissue sample processed using an ablation needle 4. In the diagram shown, the vertical axis represents the change in impedance and the horizontal axis represents time. The solid lines represent the measured values ​​and the dashed lines the simulated values. The comparator 2 can compare these values ​​and, in the event of a deviation exceeding a predefined threshold, output a comparison signal indicating that the processing procedure is not proceeding as intended. In the example shown, the impedance change profiles for three measuring electrodes 5a, 5b, and 5c are displayed. This allows the processing progress to be monitored at different locations on the object 3.

[0092] Fig. 4 shows an example of a device for the supervised execution of a processing method, where the processing method is a method for the global coagulation of biological tissue 3. For this purpose, two electrodes 4a and 4b are provided as sensors, which are inserted into the object. The electrodes 4a and 4b are connected to a measuring system 10, with which electrical quantities such as the impedance between the electrodes 4a and 4b can be measured. The measurement can also be controlled by a computer 24, which can also receive the measured values ​​and compare them with simulation results. In this way, the computer 24 can contain the comparison device 2 and be configured to compare the actual course with the expected course of the values ​​of the corresponding parameter, for example, the impedance.

[0093] The processing method is carried out here by placing the object 3 in an isotonic saline solution 41 in a water tank 42. The water tank 42 has a heater 43 with which the water in the water tank 42 can be heated. The current water temperature can be measured by means of a temperature sensor 44. To achieve a uniform temperature distribution in the water tank 42, a flow 45 is generated in the example shown. An insulating layer 46 is provided on the surface of the water in the water tank 42. In the example shown in Fig. 4, the method according to the invention is carried out in an in vitro situation, i.e., not on a human or animal body.

[0094] Fig. 5 shows an example of a preliminary planning process, based on which the method according to the invention can then be carried out.

[0095] The general therapeutic goal in tumor therapy is the complete destruction of all tumor cells while simultaneously sparing the surrounding healthy tissue and organs. In this example, the aim of pre-planning is to determine the patient-specific positioning of the ablation needle and the ablation parameters, such as duration, power, and maximum ablation temperature, so that the therapeutic goal is achieved as optimally as possible. First, the tumor tissue to be destroyed and the surrounding critical structures and organs, which should be spared as much as possible, are marked by medical personnel in the previously acquired image data (usually from CT / MRI). Then, the boundary conditions and optimization parameters are defined. The optimization can either be performed manually by a specialist (manual forward planning) or, alternatively, this optimization algorithm is automatically and iteratively minimized (inverse planning).In both cases, the positioning of the ablation needle 4 is first adjusted (1), followed by the determination of the ablation parameters (2), such as duration and power (=total energy input). A simulation model (e.g., FEM) then calculates the resulting temperatures and coagulation levels at each spatial point in the tissue. This advantageously considers the tissue morphology, electrical properties and their temperature dependence, voltage dependence, frequency dependence, the electric fields and currents, as well as the applied electrical power as heat and the heat flows, and threshold values ​​for the optimal voltage at the cell, as well as the temperature in the tissue. The expected complex frequency-dependent impedance values ​​between the individual measuring electrodes during the intervention (time-dependent) are also calculated. The simulation result is incorporated into the optimization algorithm.The adjustment of (1) and (2) is performed iteratively until the defined boundary conditions are met or no solution can be found. Subsequently, the plan is reviewed again by specialists to determine whether the therapeutic goal appears achievable with the calculated values ​​or whether further adjustments are necessary. Finally, the complex impedance values ​​expected over time for all measurement paths are calculated based on the simulation. This reference dataset can then be compared with the actual measurement data during the intervention. Based on the preliminary planning, a confidence interval (corridor) is defined for the individual complex frequency-dependent impedance values. The processing procedure itself can then follow. The method according to the invention can then be used in conjunction with this processing procedure.

[0096] At the beginning and during the intervention, the measured complex, frequency-dependent impedance values ​​ZM( E) can be used. t , E r , t) with the expected (simulated) impedance measurements Zs(E t , E r The values ​​are compared to the target values ​​(t) and calculated to determine whether they are still within the confidence interval. The system indicates whether the values ​​have left the target range or remain within it. This can be done during the intervention or at the end.

[0097] Additional information: The morphology assumed in the pre-interventional imaging during planning may differ from the tissue morphology during the intervention (e.g., differences in patient positioning, tumor growth, etc.). The actual position of the inserted needle(s) may deviate from the original plan due to inaccuracies during insertion. Further discrepancies may arise between the planned and actual power used for the ablation. All of this leads to discrepancies between reality and the simulation, which, while influencing the comparison of impedance measurements, do not necessarily affect the actual treatment success. To compensate for this, these real-world factors (position, power, etc.) can be adjusted.Data is fed back into the simulation model as feedback, allowing for a one-time adjustment before or continuous adaptation of the simulation model to the intervention. The calculated target impedances from the simulation results can then be compared with the actual impedances of the measuring device.

[0098] An example of the inventive method with an optical sensor may look like this:

[0099] 1.) Based on the imaging data and the planned treatment (position of the needle probes), an in-silico model of the treatment process is calculated (e.g., using FEM). This can take into account the tissue morphology, electrical properties and their temperature dependence, voltage dependence, frequency dependence, the electric fields and currents, as well as the electrical power input as heat and the heat flows, and threshold values ​​for the optimal voltage at the cell and the temperature in the tissue. The expected heat flows and temperature gradients at the needle probe during the intervention (time-dependent) can also be calculated.

[0100] 2.) Based on 1.), a time-dependent expected value and a confidence interval (corridor) can be determined for the absolute and relative (difference temperature) temperature profiles.

[0101] 3.) At the beginning and during the intervention, the temperatures, if available, along and / or inside the needle probe and, if applicable, reference temperatures can be continuously recorded and compared with the corridor from 2.) (absolute value and temporal and spatial derivatives).

[0102] It can be displayed if the values ​​from step 3) have left the target corridor from step 2) or whether the measured values ​​are within the target corridor. This can be done during the intervention or at the end.

[0103] Figure 6 shows an example of a simulation of the expected progression of the processing procedure using a simulation model. In a first step, S1, the input of energy into the tissue to be processed and its propagation within the tissue are simulated in S2. The propagating energy leads to changes in conductivity and permittivity within the tissue, which are simulated in S3. From the results of this simulation with steps S1, S2, and S3, a complex impedance of the tissue is then simulated in a subsequent step, S4.

[0104] In detail, the following approach is one example of how this can be done.

[0105] 1.) Energy, e.g., microwave energy, is introduced. In the case of microwave energy, for example, the power radiation of the antenna is approximated and depends on the local temporal electrical conductivity. The antenna's power fields can be adapted to the manufacturer's antenna design. Furthermore, backscattering (i.e., the power not radiated into the tissue) could also be considered as an additional factor in the tissue ablation model.

[0106] 2.) The simulation of heat propagation uses, for example, the following temperature equation, which can be derived from the first law of thermodynamics. This law describes the principle of energy conservation. Here, p represents the density, Cp the specific heat capacity, and k the thermal conductivity of the material.

[0107] 20

[0108] 3.) The changes in conductivity ff and permittivity f are calculated as a function of time and temperature.

[0109] The temperature effect is approximated quadratically, and the coagulation effect is determined using the Arrhenius equation, which takes time and temperature into account. The output is the proportion of coagulated tissue, ranging from 0.0 to 1.0. The coefficients a, b, and c are parameterized through laboratory (in vitro) experiments. The electrical properties of the liver are simplified using an RC parallel circuit, where the path through the cell walls can be described by the capacitance and the path through the intercellular space by the resistive component.

[0110] The following effects are advantageous for good modeling of the coagulation process: Depending on temperature, time and location, one or more of the following can be advantageously modeled: the influence of the cell membrane on the permittivity, cell rupture, tissue carbonization and / or the contact area of ​​the electrodes to the tissue.

[0111] An evaluation / comparison logic between measurement and simulation model can be implemented, for example, as follows.

[0112] Figure 7 shows impedance measurements at 100 kHz and 110 °C as a function of time. The left side of Figure 7 shows the magnitude of the impedance, and the right side shows the phase of the impedance. The measurements reveal inflection points in the magnitude, which occur simultaneously with the respective phase rise of the electrode combination. Measurements have shown that the tissue coagulates concurrently with these inflection points and phase rises, and that these could mark the arrival of the coagulation front.

[0113] One possible explanation is that the rupture of the cell membrane upon arrival of the coagulation front alters the capacitive properties of the tissue, leading to a phase increase. This may then allow ions to flow into the cell, increasing the tissue's conductivity.

[0114] Temperature and tissue state (coagulated versus native) have a known effect on tissue conductivity. Without a change in state, a relative change in conductivity is reflected in a change in amplitude. A sometimes irreversible change in tissue, such as coagulation, leads to a disruption of the cell membrane and thus to a sometimes irreversible change in the capacitive electrical properties of the tissue. A turning point in the magnitude curve and / or an increase in the phase shift (marked by a box K in Fig. 7) can be used to detect the axial arrival of the coagulation front at an electrode ("reach of the coagulation front at electrode").

[0115] The tissue impedance model should preferably take these reproducibly observed measurement effects into account. For this purpose, the permittivity change model is extended by a term that replicates the phase transition behavior. However, the model is not limited to evaluating the transition behavior or individual aspects. All characteristics (e.g., also temperature trends during tissue heating) can be advantageously considered.

[0116] The comparison between measurement and simulation is carried out, for example, using features in the time series, as well as the nth derivative of these time series. These features can be inflection points, minima, maxima, and gradients.

[0117] It might also be possible to determine the local axial arrival of the coagulation front at the electrodes using only the measurement data, if inflection points and gradients in magnitude and phase are used. However, this only provides information about the coagulation front directly along the needle and not in three-dimensional propagation. This information can be obtained indirectly through simulation.

[0118] It can be assumed that the evaluation logic can also be applied to other thermal ablation methods.

[0119] An improvement in the measuring device can also be achieved if the impedance measurement is performed during the off-duty phases of the MWA and time-triggered. This means that a measurement is only taken when the MWA cannot couple into the measuring system. This avoids interference in the measurement signal.

[0120] Fig. 8 shows an example of an ablation needle with six electrodes 5a, 5b, 5c, 5d, 5e, 5f. Electrodes 5e and 5f are polarized opposite to electrodes 5a, 5b, 5c, and 5d. When a voltage is applied, field lines 82a, 82b, 82c, 82d are formed. These lines extend further into the surrounding tissue the greater the distance between the electrodes. Each field line can therefore be considered a measurement path whose impedance depends on whether and how far it passes through the coagulated area 83.

[0121] The ratio / calculation / comparison of several measurement paths between electrodes 5a to 5f, which are located at different distances, provides information about:

[0122] - the spread of the coagulation zone 83 in axial and radial direction to the measuring needle

[0123] - the morphology and position of different tissue types

[0124] - the morphology and position of tumor tissue

[0125] Explanation: The current density distribution in the tissue depends on the distances between electrodes 5a to 5f. The greater the distance between two electrodes 5a to 5f, i.e., the longer the measurement path through the tissue, the more widely distributed the current density lines are in the radial direction to the measuring needle (a Schlumberger circuit can be used for this purpose). In the example shown in Fig. 8, path 82a between electrodes 5e and 5d therefore provides a core area measurement, while path 82d between electrodes 5f and 5a provides a periphery measurement.

[0126] The measured effect is partly composed of the volume traversed by the electric field lines 82a - 82d. Therefore, effects on the amplitude and phase occur at different times, with different strengths and at different rates of change between different electrode pairs, whereby electrodes 5a to 5f located close together are more likely to reflect a change in a localized volume than electrode pairs 5a to 5f located further apart.

[0127] Due to the initially not fully defined electrical properties of the tissue and the contact to the measuring unit, relative measured values ​​are preferably considered.

[0128] The temporal profiles of the magnitude and phase changes of the individual measurement paths 82a–82d between electrodes 5a to 5f are the result of a superposition of irreversible and reversible components. The reversible component of the impedance change is a consequence of a "temperature effect." In the case of a theoretically sudden temperature increase, the tissue impedance would change instantaneously. A subsequent, immediately following sudden drop back to the tissue's original temperature would not result in coagulation, and the tissue impedance would return to its original value (temperature effect = reversible component). The irreversible component of the impedance change is a consequence of tissue coagulation, depending on the total energy delivered to the tissue. If the delivered power (pin) and the tissue properties and morphology (e.g.,(known through tomographic imaging), the magnitude and position of the temperature increase can be quantitatively determined over time by the impedance changes.

[0129] Fig. 9 shows the signal waveform of the electrical impedance magnitude during a procedure. The signal waveforms of the measurements between four electrodes before, during, and after ablation are depicted. The measurement paths of Channel 0 and Channel 1 pass through tissue without any residual coagulation effect, as evidenced by the reversible impedance change after cooling of the tissue. This temporary impedance change was solely due to the temperature effect. Channel 2 and Channel 3 show an irreversible impedance change, as their measurement paths pass through tissue with permanent coagulation.

Claims

Patent claims 1. A method for monitoring a processing procedure, wherein the processing procedure is a procedure for processing biological tissue, wherein first an expected course of the processing procedure is simulated using a simulation model, and thereby an expected course of values ​​of at least one parameter during the processing procedure is predetermined, then during an execution of the processing procedure an actual course of values ​​of the at least one parameter is measured and / or calculated from measurements, and the actual course is compared with the expected course of the values ​​of the corresponding parameter, and in the event that the comparison shows that a deviation between the actual course and the expected course is greater than a predetermined threshold, a comparison signal is output indicating that the processing procedure is not proceeding as intended.

2. A method according to the preceding claim, wherein the method is a method for monitoring the removal and / or destruction of a tumor as the biological tissue, wherein, firstly, as the expected course of the processing method, an expected course of the removal of the tumor is simulated using the simulation model, and thereby, as the expected course of values, an expected course of values ​​of at least one parameter during the removal and / or destruction of the tumor is predetermined. Then, during the execution of the removal and / or destruction, an actual course of values ​​of at least one parameter is measured and / or calculated from measurements, and the actual course is compared with the expected course of values ​​of the corresponding parameter, and in the event that the comparison shows that the deviation between the actual course and the expected course is greater than a predefined threshold, the comparison signal is output, indicating that the removal and / or destruction is not proceeding as intended.

3. A method according to any of the preceding claims, wherein the method is a method for the thermal destruction of biological tissue, preferably for thermal destruction by means of microwaves.

4. Method according to one of the preceding claims, wherein the simulation of the expected course of the processing method in a first step comprises a simulation, preferably resolved in place, of a propagation of energy introduced into the tissue for the purpose of destroying the tissue and preferably of a resulting temperature change, and wherein the simulation method in a second step comprises a simulation of the expected course of the values ​​of the at least one parameter based on results of the simulation in the first step.

5. Method according to any of the preceding claims, wherein at least one of the at least one parameter is an impedance, an impedance change, an imaginary part of an impedance, an imaginary part of an impedance change, a temperature, a temperature change, a fluorescence change, for example of a tracer, a permeability of tissue and / or a tracer, and / or a permittivity of tissue and / or a tracer.

6. A method according to any of the preceding claims, wherein the following is compared to compare the actual course with the expected course: an occurrence, a time point and / or a course of at least one feature, wherein the feature is a feature of the course and / or a gradient of the course and / or an nth derivative of the course, with n greater than or equal to 1, and / or an integral over at least a part of the course, wherein preferably the at least one feature is a discontinuity, a maximum, a minimum, a saddle point, an overriding and / or falling below a minimum of a value, a time point at which a predetermined value is reached, an overriding and / or falling below a maximum of a value, a reaching of a predetermined value, and / or an overriding and / or falling below a time offset with respect to passing through at least one marker value between two measuring points.

7. Method according to one of the preceding claims, wherein a difference and / or a quotient between values ​​of the actual course and the expected course is calculated to compare the actual course with the expected course.

8. Method according to any of the preceding claims, wherein the simulation model is a finite element model in which an object or body in which the machining process is carried out, as well as devices used therefor, are modeled by means of finite elements and / or wherein the simulation model is an analytical model that models an object or body in which the machining process is carried out, as well as devices used therefor, and / or wherein the simulation model is a deep learning and / or artificial intelligence model that models an object or body in which the machining process is carried out, as well as devices used therefor.

9. Method according to one of the preceding claims, wherein the processing method is a method in which energy is introduced into an object or body by means of at least one probe, wherein the at least one probe has at least one sensor for measuring the values ​​of the corresponding parameter, wherein preferably at least one of the at least one sensors is an electrode via which an alternating voltage can be applied to at least one area of ​​the object or body.

10. Method according to one of the preceding claims, wherein, for measuring the values ​​of the at least one parameter, an alternating voltage is applied to at least one area of ​​the object or body to be treated via a plurality of electrodes, wherein preferably at least one of the electrodes is arranged on a surface of the object or body, preferably in contact with it.

11. Method according to the preceding claim, wherein the alternating voltage is applied between any two of the electrodes, preferably between exactly two of the electrodes simultaneously, and wherein the alternating voltage is preferably applied at different times between different of the electrodes.

12. Method according to one of the two preceding claims, wherein an alternating voltage with a first frequency is applied between at least two first electrodes and an alternating voltage with a second frequency different from the first is applied between at least two second electrodes, of which at least one electrode is not one of the first electrodes.

13. A method according to any one of the three preceding claims, wherein voltages are applied between at least two first electrodes which are phase-space separated from voltages applied between at least two second electrodes, wherein at least one of the at least two second electrodes is not one of the first electrodes, and / or wherein voltages are applied between at least two first electrodes in different spatial regions than between at least two second electrodes, wherein at least one of the at least two second electrodes is not one of the first electrodes, and / or wherein voltages between at least two of the electrodes are shielded from voltages between other electrodes by active electrical separation, e.g. by an opposing field.

14. Method according to one of claims 10 to 13, wherein the plurality of electrodes are arranged as an array on one, two or more than two probes for carrying out the processing.

15. Method according to any of the preceding claims, wherein the simulation predetermines the course of the values ​​of the at least one parameter using at least one tissue parameter and / or at least one treatment parameter and / or at least one electrode geometry.

16. Method according to any one of claims 10 to 15, wherein the electrodes are interconnected in a Schlumberger / Wenner configuration.

17. A method according to any of the preceding claims, wherein the following is compared to compare the actual course with the expected course: an occurrence, a time point and / or a course of at least one feature, wherein the at least one feature is one or more of the following features: a relative and absolute change of an amplitude between different electrodes, a slope of a change of an amplitude between different electrodes, an asymptotically targeted course and / or a time interval between a constant value and an increase or decrease. The amplitude change between different electrodes, a relative and absolute change in phase between different electrode pairs, the slope of a change in phase between different electrode pairs, an asymptotically targeted course and / or a time interval between a constant value and an increase or decrease in phase between different electrode pairs, 18. Method according to one of the preceding claims, wherein the simulation model is updated based on the comparison of the actual course with the expected course in such a way that the deviation between the actual course and the expected course is reduced, wherein preferably the simulation model is updated by means of differences and / or quotients between the values ​​of the actual course and the values ​​of the expected course, such that the expected values ​​have a smaller difference to the actual values ​​or the quotients are closer to one.

19. Method according to one of the preceding claims, wherein the processing method is controlled and / or regulated on the basis of a comparison of the actual course with the corresponding expected course.

20. Method according to one of the preceding claims, wherein at least one property of an object or body to be processed is determined on the basis of the comparison, preferably a coagulation, clotting, denaturation of protein-based cell components and / or a cell integrity.

21. Method according to one of the preceding claims, wherein the machining method is planned in advance using the simulation model.

22. Method according to one of the preceding claims, wherein the notification that the processing method is not proceeding as intended includes a notification as to whether over- or under-processing has occurred.

23. Device for the supervised execution of a processing method, wherein the processing method is a method for processing biological tissue, comprising at least one simulation system configured to simulate an expected course of the processing method using a simulation model and thereby predicting an expected course of values ​​of at least one parameter during the processing method, at least one processing device configured to execute the processing method, at least one sensor configured to measure an actual course of values ​​of the at least one parameter during the execution of the processing method, and a comparison device configured to compare the actual course with the expected course of values ​​of the corresponding parameter and, in the event thatthat if the deviation between the actual progress and the expected progress exceeds a predefined threshold, a comparison signal is output indicating that the processing procedure is not proceeding as intended.

24. Device according to the preceding claim, wherein the processing device has at least one ablation needle for tumor removal and / or wherein the at least one sensor has at least one electrode, preferably at least two electrodes.

25. Device according to one of the two preceding claims, wherein the sensor is a temperature sensor, preferably with a fiber Bragg grating, wherein preferably at least two temperature sensors are provided as sensors.

26. Device according to any one of claims 23 to 25, wherein the device is configured to perform a method according to any one of claims 1 to 22.

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