System and method for detecting shading of excitation radiation emitted towards a medical scene

Abstract

The invention relates to a system (100) and to a method for detecting shading (Y) of excitation radiation (12) emitted towards a medical scene (1). For this purpose, comparative images (31, 32) are taken in various illumination situations (21, 22), which images are compared with one another. The illumination situations are selected such that they have to be different (alternatively: identical) in the presence (Y) of shading and have to be identical (alternatively: different) in the absence (N) of shading. In the presence (Y) of shading, various measures can be taken, for example a modified representation of the shaded region (5) in the image (51) by a display device (150), a modified evaluation by an analysis module (160), and / or the like.

Description

[0001] Description Title 5 System and method for detecting shadowing of excitation radiation emitted in the direction of a medical scene Technical field of the invention 10 The present invention relates to a system and a method for detecting shadowing of excitation radiation emitted in the direction of a medical scene. Excitation radiation can, for example, be NIR 15 (near-infrared) excitation light for the representation of ICG (indocyanine green). Background of the invention 20 In a medical, particularly surgical, context, excitation radiation is often used in addition to white light for illumination. White light corresponds in its spectrum to natural sunlight and is therefore very easily detectable by the human eye. 25 The use of fluorescence imaging and additional excitation radiation is used toparticularly in tissue, in or on a patient, in a way that is not possible with pure white light. In the well-known ICG excitation, for example, the dye indocyanine green (ICG) is introduced into a tissue and excited there with an excitation light source in the near-infrared spectrum. This can absorb electromagnetic radiation with wavelengths between 600 nm (nanometers) and 900 nm (nanometers) and emit fluorescent light with wavelengths between 750 nm (nanometers) and 950 nm (nanometers). Since the dye binds to plasma proteins and thus only accumulates in certain areas, blood circulation or lymph flow, for example, can be visualized in this way. Since, for example, electromagnetic radiation in both wavelength ranges, especially in the emitted wavelength range, is invisible to the human eye, the user,For example, a surgeon, here relies on the support of, for example, a medical imaging system 15 that can detect the invisible electromagnetic radiation and make it visible to the user on a display device. If one type of tissue is to be distinguished from another 20 exclusively or primarily by whether or not the tissue type emits electromagnetic radiation of a certain wavelength, it is desirable that the entire medical scene, but in particular the image section to be observed, 25 be completely illuminated with the excitation radiation. In this way, it can be ensured that a tissue site that is not currently emitting any fluorescence radiation actually does not emit any fluorescence radiation because the dye is not present there, and not, for example, 30 becausebecause the excitation radiation did not reach there. Especially when both the excitation radiation and the emitted fluorescent radiation are invisible to the human eye, it is difficult for a human user to determine which case is currently present. 5 During laboratory work or a medical procedure, shadows of the excitation radiation often occur, for example, due to devices, instruments, the hands of a user, and the like. What makes matters worse is that shadows of the excitation radiation do not necessarily mean complete (or even partial) shadowing of the white light incident on the same area. Due to various light scattering in or on the medical scene as well as other light sources in the environment, there is often sufficient illumination by white light, which can falsely suggest to a user thatthat sufficient irradiation with excitation radiation is present, even if shadowing is actually present. 20 Fig. 9a shows, by way of example, a medical scene 1 with a tissue 3 to be inspected, which has a section 4 that is mixed (or enriched) with a marker (or dye), e.g., ICG. The excitation radiation generates excited radiation in the 25 marker, which is detected and placed, for example, as an overlay on a screen over the normal visible image. Objects such as instruments 2 can block the illumination with excitation radiation, i.e., shadow the medical scene 1, in particular parts of section 4. 30 Fig. 9b shows, by way of example, the same medical scene 1 as in Fig. 9a, but with partial shadowing of section 4, which has the ICG marker, in a shadowed area 5. On the user's display device, it can now look like this:as if the section 4 offset with the marker were significantly smaller than it actually is, which can complicate the correct analysis of the medical scene 15. Fig. 9c shows a drawn representation of the medical scene 1 from Fig. 9a, and Fig. 9d shows a drawn representation of the medical scene 1 from Fig. 9b. 10 Summary of the Invention It is therefore an object of the present invention to provide a system and a method which each improves the use of excitation radiation in a medical scene, in particular making it safer and more reliable. Furthermore, it is an object to provide a corresponding computer program,to provide a corresponding data storage medium and a corresponding data stream. 20 The problems described above are solved by the subject matter of the independent claims of the present invention. 25 According to a first aspect, a system is provided for detecting shadowing of excitation radiation emitted in the direction of (or onto) a medical scene, comprising: a light-emitting device configured to emit light, which comprises at least visible light, in the direction of the medical scene; an excitation-emitting device configured to emit the excitation radiation in the direction of the medical scene; an image capture device configured to capture images by detecting electromagnetic radiation,which comprises a) at least a portion (in particular a spectral portion and / or a portion of the emission power) of the light emittable by the light-emitting device (or light emitted) and b) at least a portion (in particular a spectral portion and / or a portion of the emission power) of an excited radiation excited by the excitation-emitting device in the medical scene 15; a control device configured to control the light-emitting device and the excitation-emitting device, wherein the control device comprises a shadow detection module configured to perform a shadow detection method comprising the steps of: - controlling the light-emitting device and the excitation-emitting device such that they emit the light and / or the excitation radiation onto the medical scene 25,to generate a first lighting situation; - controlling the image capture device such that it captures an image of the medical scene in the first lighting situation in order to generate a first comparison image; - controlling the light emission device and / or the excitation emission device such that it changes at least one property of the emitted light or the emitted excitation radiation in comparison to the first lighting situation in order to generate a second lighting situation; - controlling the image capture device such that it captures an image of the medical scene in the second lighting situation in order to generate a second comparison image; - detecting a shadowing of the excitation radiation emitted in the direction of the medical scene by comparing the first comparison image with the second comparison image; and - outputting an output signal which at least indicates,whether shadowing, in particular of the excitation radiation, is present. Additionally, simultaneously, or alternatively, it can also be detected 20 whether the light emitted by the light-emitting device is shadowed in at least one area of ​​the medical scene. Shadowing is to be understood in particular as meaning that at least one area in the medical scene is not illuminated by the corresponding radiation 25 (e.g., light or excitation radiation) from the light-emitting device or excitation-emitting device. The shadowing detection module can be configured to convert a detected shadowing of the light into a shadowing of the excitation radiation 30 and / or vice versa. For this purpose, it can have conversion data or comprise and use a rule-based algorithm or a machine learning algorithm (e.g., an artificial intelligence entity such as an artificial neural network). Among these,The fact that the image capture device is configured to capture images by detecting electromagnetic radiation comprising at least a portion of the light emittable (or emitted) by the light-emitting device is to be understood in particular as meaning that the light emitted by the light-emitting device, e.g., white light, impinges on the medical scene, from there at least partially returns to the image capture device (e.g., through refraction, diffraction, scattering, reflection, etc.), and is then detectable there. Accordingly, typically only a portion of the emitted emission power will be detected, and only a spectral portion of the emitted light will be detected, since the image capture device is typically not sensitive (or receptive) to all wavelengths, at least not completely. 20 The fact that the image capture device is configured to capture imagesby detecting electromagnetic radiation that comprises at least a portion of excited radiation that was excited by the 25 excitation-emission device in the medical scene, it should be understood in particular that at least a portion of the total emission power of the excited radiation is detected and / or that at least a spectral component of the excited radiation is detected. 30 The light emission device and / or the excitation-emission device, on the one hand, and the image acquisition device, on the other hand, can be controlled by the control device in a synchronized manner, in particular frame-synchronously. This allows, for example, the emission power of the light emission device and / or the excitation-emission device, on the one hand, and an exposure control of the image acquisition device, on the other hand, to be adapted to one another.For example, to achieve a constant brightness in the comparison images—apart from the shadowed areas—despite changing properties of light and / or excitation radiation. This can further simplify the automatic detection of shadows or shadowed areas. A fundamental idea of ​​the present invention is thus that, if the lighting situation of the medical scene changes, the entire medical scene should be represented in the same changed manner in the comparison images recorded. However, if an area in the medical scene remains unchanged in the recorded comparison images (or changes in a different way than the remaining areas), this means that the entire medical scene is not or was not illuminated in the same way. Thus, shadowing exists. In this way, the present invention has the great advantage ofthat a shadow can be reliably detected and communicated to a user. The user thus receives highly useful information about the internal state of the system, which can also be described as an (improved) medical imaging system or image acquisition system, and which would otherwise not be available to him due to the limited spectral sensitivity of the human eye. As will be discussed in more detail below, this inventive basic idea further enables the system to be further developed in a variety of ways to improve the user's level of information, perform automatic corrections,Offer warnings or suggestions for behavior, and the like. The system according to the invention can preferably comprise an endoscope (for insertion into a patient and for capturing images from there) or an exoscope (for capturing images of a patient from outside the patient's body), particularly preferably an exoscope. With exoscopes, due to the additional white light illumination often incident from many directions (e.g., ceiling lights in an operating room, windows with daylight, surgical lights, and the like), it is particularly difficult to perceive the shadowing of the light emitted by the light-emitting device in an area of ​​the medical scene, since the area is often strongly illuminated by the additional incident illumination, but actually receives neither the light from the light-emitting device nor—much more importantly—the excitation radiation. 25 The light-emitting device,The excitation-emission device and / or the image acquisition device can be fully or partially integrated into a camera head of the endoscope or exoscope, respectively. A system according to the invention, which comprises an endoscope or exoscope, can also be referred to as an endoscope system or exoscope system with shadow detection. The term "medical scene" is defined broadly here: It can refer to a scene in a building dedicated to medical purposes, for example, a medical research institute, a hospital, a medical university, a doctor's private practice, the interior of an ambulance, and an external or even internal view of a patient who is currently undergoing or is about to undergo a medical procedure. On the other hand, a medical scene can also be a scene created using a medical front-end device,which comprises a camera, wherein the medical front-end device is a medical instrument such as an endoscope, an exoscope or the like 15. In particular, the medical scene can be a scene in which an organic, in particular human, tissue can be seen, for example in a laboratory or an operating room, either in vitro and / or in vivo. The medical scene 20 can be a scene in which a dye or endogenous fluorophore is present, which is excited by the excitation radiation from the excitation-emission device, ie,to emit excited radiation. 25 The light-emitting device can, in particular, be a white light source. Accordingly, the light emitted by the light-emitting device can be white light or the light emitted by the light-emitting device can comprise white light. The excitation-emitting device can, in particular, be a light source in the infrared range, in particular in the near-infrared range. The excitation radiation can, in particular, be such that it effects or causes excited radiation, in particular in an organic tissue, through luminescence, 5 ie, in particular fluorescence. The excitation radiation can be such that the luminescence only occurs,when a fluorophore is excited. Depending on the application and 10 indication, artificially added fluorophores can be used as markers in addition to or as an alternative to a patient's own fluorophores. Although some 15 functions are described here, above, and below as being performed by "devices" or "modules," it should be understood that this does not necessarily mean that such devices or modules are provided as separate entities. In cases where one or more devices or modules 20 are provided in whole or in part as software, the devices may be implemented by program code sections or program code snippets that are distinct from one another but may also be interwoven. 25 Similarly, in the case where one or more devices or modules are provided as hardware,the functions of one or more devices or modules are provided by one and the same hardware component 30, or the functions of a device or the functions of several devices or modules can be distributed across several hardware components, which do not necessarily have to correspond one-to-one to the devices or modules. Therefore, any device, system, method, etc., that has all the features and functions attributed to a specific device and / or module is to be understood as 5 forming, comprising, or implementing the device and / or module. In particular, it is possible for all modules to be implemented by program code executed by a computing device 10. The computing device can be realized as any device or means for computing, in particular for executing software,an app or an algorithm. 15 For example, the computing device may include at least one processor, such as at least one central processor, CPU, and / or at least one graphics processor, GPU, and / or at least one field-programmable gate array, FPGA, and / or at least one application-specific integrated circuit, ASIC, and / or any combination of the foregoing. The computing device may further include a memory operatively connected to the at least one processor and / or a non-volatile memory operatively connected to the at least one processor 25 and / or the memory. The computing device may be partially and / or entirely implemented in a local device and / or partially and / or entirely implemented in a remote system, such as through a cloud computing platform.be implemented. 30 According to a second aspect, the present invention provides a computer-implemented method for detecting shadowing of excitation radiation emitted toward a medical scene. The method comprises at least the steps of: - emitting light, which comprises at least visible light, and / or excitation radiation onto the medical scene to create a first lighting situation; - capturing an image of the medical scene in the first lighting situation to create a first comparison image; - changing at least one property of the emitted light and / or the emitted excitation radiation, compared to the first lighting situation, to create a second lighting situation; - capturing an image of the medical scene in the second lighting situation,to generate a second comparison image; - detecting a shadowing of the excitation radiation 20 emitted towards the medical scene by comparing the first comparison image with the second comparison image; and - outputting an output signal that at least indicates whether the excitation radiation emitted towards the medical scene is shadowed in any area 25. According to a third aspect, the invention provides a computer program product comprising executable program code that is configured, when executed by a computing device, to perform the method according to an embodiment of the second aspect of the present invention. According to a fourth aspect, the invention provides a non-transitory, computer-readable data storage medium comprising executable program code that is configured, when executed by a computing device,5 to carry out the method according to an embodiment of the second aspect of the present invention. The non-volatile, computer-readable data storage medium may comprise or consist of any type of computer memory, in particular 10 semiconductor memory, such as a solid-state memory. The data carrier may also comprise or consist of a CD, a DVD, a Blu-ray disc, a USB memory stick, or the like. 15 According to a fifth aspect, the invention provides a data stream comprising executable program code or configured to generate executable program code, which, when executed by a computing device, is configured to carry out the method according to an embodiment of the second aspect of the present invention. According to some preferred embodiments,In variants or refinements of embodiments, the 25 excitation radiation and / or the excited radiation is invisible electromagnetic radiation. Invisible electromagnetic radiation is understood to mean, in particular, electromagnetic radiation that is not visible to the human eye without aids, such as 30 ultraviolet radiation or infrared radiation. The invisible electromagnetic radiation, in particular the excited radiation, can, for example, be in the wavelength range between 750 nm or 780 nm and 950 nm. The invisible electromagnetic radiation, in particular the excitation radiation, can also, for example, be in the wavelength range between 750 nm or 780 nm and 900 nm. The invisible electromagnetic radiation can be disjoint from 5 white light, or overlap with it only in one wavelength range,which is not detectable by the human eye. However, the present invention can also be advantageous for visible 10 and / or only slightly visible electromagnetic radiation (e.g., excitation radiation or excited radiation, which comprise a small proportion of visible light), for example because the corresponding light intensities can be so small that they are indistinguishable from the surrounding white light for the 15 human eye. In such cases, the sequential illumination of the medical scene with visible light (e.g., white light) and the excitation radiation during normal operation, but also for detecting the shadowing according to the present invention, can be advantageous so that the received electromagnetic radiation can be causally assigned to one of the two radiations on a time-based basis. 25 Furthermore, further processing, for example, analyses,based on the detected excited radiation. Such analyses can be automatically adjusted when shadowing is detected. In these cases, the present invention is useful even if the shadowing is or could potentially be detected by a human user, since the user then does not have to make or request the adjustment themselves; rather, it can be carried out automatically. Furthermore, in many variants, the excitation radiation is blocked by an observation filter. According to some preferred embodiments, variants, or refinements of embodiments, the at least one changed property comprises an emission power of the light emitted by the light-emitting device. The change in the emission power can, in particular, be a change from 0 to a value X>0, from a value X>0 to another value Y>0,and / or from a value X>0 to 0. Since the excited radiation can often only be emitted when the tissue of interest is impinged with a dye or 15 fluorophore, the emission power of the excited radiation is usually relatively low. Therefore, the device (e.g., a medical imaging system or image acquisition system) is advantageously configured so that a maximum emission power of the 20 excited radiation is already generated during normal operation. Changing the emission power of the light emitted by the light-emitting device (e.g., white light) thus generally has more recognizable effects on the illumination situation for the purpose of shadow detection. 25 In some variants, however, a property of the excitation radiation can also be changed,in particular, an emission power of the excitation radiation. The change in the emission power can, in particular, comprise a change from 0 30 to a value X>0, from a value X>0 to another value Y>0, and / or from a value X>0 to 0. Finally, a change in one or more properties of both the light emitted by the light-emitting device and the excitation radiation is also conceivable. A change in a property of the light and / or the excitation radiation can, according to the foregoing, also consist in the fact that it is emitted at all (in the second illumination situation) where it was not previously emitted, or is no longer emitted.where it was previously emitted. 10 A change in the emission power itself is generally simpler and more easily detectable than, for example, a change in the spectral composition (either the light emitted by the light-emitting device and / or the excitation radiation), which is also possible. Changing the emission power is, in particular, a reduction in the emission power. Increasing the emission power, although possible in principle, is rarely desired, since the maximum possible, permitted, or tolerable emission power is usually emitted anyway in order to enable the best possible optical / visual detection of the medical scene or excitation of excited radiation. Therefore, it is often technically easier to reduce the emission power (either the light emitted by the light-emitting device and / or the excitation radiation) than to increase it. As already mentioned,A change in emission power is relatively easy to detect and quantify, thus representing a particularly advantageous method for detecting shadowing. It is also possible for more than two different lighting situations to be created consecutively, directly or indirectly, thereby generating more than two comparison images. For example, if neither the first lighting situation B1 nor the second lighting situation is a usual / desired lighting situation BN for normal operation, a sequence BN-B1-BN-B2 or BN-B1-B2 can be repeated cyclically, with each BN, B1, and B2 representing one frame or a predetermined number of multiple frames. Thus, additional comparisons can be performed, which can make the detection of shadowing even more accurate and / or which can be used for plausibility checks. 15 According to some preferred embodiments,In variants or refinements of embodiments, the shadow detection module is configured to perform the shadow detection method regularly and / or on request. 20 Regular execution can occur, for example, between 0.25 times per second and 120 times per second, preferably between 0.5 times per second and 60 times per second, particularly preferably once per second. 25 For example, the device can record 120 frames per second, of which a first frame is recorded alternately in the first lighting situation, and a second frame is recorded in the second lighting situation. One of the two 30 lighting situations, for example the first, can then be designed for normal operation.and, for example, simultaneous emission of light by the light-emitting device and the excitation radiation. Thus, a frame rate of 60 Hz (with the first illumination situation) is available for normal operation, while at the same time a 5 shadowing is detected very precisely and accurately (also at 60 Hz), with the frames from normal operation serving as the first comparison images in this example. Particularly preferably, outside of the shadowing 10 detection process, the first illumination situation (as a standard illumination situation, i.e., for normal operation) is maintained. In other words, the first illumination situation is advantageously interrupted only by short (especially regular) periods (e.g., 8 to 15, 2000 milliseconds).in which the second lighting situation is established due to the shadow detection method. A request for the shadow detection method can be made, for example, by actuating a user interface, for example, by a voice command, pressing a button, a switch, a foot pedal, or the like. This can occur, for example, if a user of the system has a suspicion or fear that shadowing is present, or wants to be particularly sure that no shadowing is present. According to some preferred embodiments,In variants or refinements of embodiments, the light emittable by the light-emitting device and the excitation radiation emittable by the excitation-emitting device are disjoint in the electromagnetic spectrum. In this way, excitation radiation and emitted light can be separated even better. The excited radiation typically has a lower frequency spectrum than the excitation radiation, which preferably has a lower frequency spectrum than the light emittable or emitted by the light-emitting device. The light-emitting device and the excitation-emitting device can be configured such that they emit (or transmit) the light and the excitation radiation simultaneously (alternatively sequentially). The first and / or second illumination situation can thus be an illumination situation,in which light and excitation radiation are emitted or present simultaneously. Alternatively, the first 15 and / or the second illumination situation can be an illumination situation in which only either the light or (XOR) the excitation radiation is emitted or present. 20 The light-emitting device and the excitation-emitting device can have a common light source in which the light and the excitation radiation are generated and mixed, in order to be guided from there via a light guide of the device to a common 25 exit point. The simultaneous or sequential emission of the different radiations can thus take place by mixing on the one hand or by time-delayed generation or lack of mixing on the other hand. 30 According to some preferred embodiments, variants or refinements of embodiments, the system has a display device which is configured toto display an image based on the output signal and on an image currently captured by the image capture device, preferably in real time. The display device can place an overlay 5 over the image of the medical scene visible to a human, which overlay indicates or displays the emission locations of the excited radiation. In other words, the overlay can show a user the areas of the medical scene in which the excited radiation is generated and which thus, for example, have a marker (or dye) 10. This can be done, for example, by overlaying with a partially transparent colored surface, by bordering, or the like. The display device can be, for example, a monitor 15, in particular a monitor suitable for an operating room, a touchscreen,or a mobile device such as a tablet or a smartphone. The display device can have a graphical user interface and thus also implement a graphical user interface, optionally in conjunction with other input devices such as a keyboard, a mouse, a trackball, a joystick, a pedal, a switch, a touchscreen, or the like. The display device can thus also represent an input device. According to some preferred embodiments, variants, or refinements of embodiments, the output signal includes information about an area in the medical scene in which the excitation radiation is shadowed, if such an area exists. In a simple variant, this information from the output signal can be used to generate an acoustic, optical, and / or visual warning signal.For example, to output the voice signal "Shading" or a warning tone, to activate a warning light or change its color, to display or change a visual or graphical indication in a graphical user interface of the display device, or the like. According to some preferred embodiments, variants, or refinements of embodiments, the display device is configured to visually mark the area (which does not have to be contiguous) in which the excitation radiation is shadowed (or has been detected as shadowed) in the image currently captured by the image capture device. For example, the overlay impressed on or superimposed on the visible image can be displayed differently by the display device in the shadowed areas (for example, in a different color or with a different pattern) than in the non-shadowed areas. A user,who relies on the overlay for his analysis or diagnosis thus knows at that moment that the currently displayed overlay may be incorrect or incomplete. 25 According to some preferred embodiments, variants, or refinements of embodiments, the system comprises a compensation module configured to replace the region in which the excitation radiation is shadowed 30 in the image displayed by the display device with substitute image data or to replace the entire displayed image with the substitute image data while (or: as long as) the excitation radiation is shadowed therein. The substitute image data can be generated in particular from images previously acquired by the image acquisition device, in particular based on previously acquired images for which, at least in the region for which the substitute image data is generated,no shadowing was detected. Alternatively, the substitute image data can also be based on or consist of a temporal averaging over a predefined number (e.g., between 2 and 180, in particular between 50 and 100) of previously acquired images. 10 According to some preferred embodiments, variants, or refinements of embodiments, the system further comprises an analysis module configured to perform an analysis of images acquired by the image acquisition device based on their spectral properties. The analysis module can be configured such that regions in which the excitation radiation is shadowed are excluded from the analysis. Such analyses comprise, for example, the acquisition and evaluation of ratios of wavelength intensities and can therefore be falsified if certain wavelengths, which should actually be emitted by the medical scene,cannot be detected because corresponding areas are shaded. For example, a ratio of blue / bluish light to red / reddish light can indicate tissue oxygenation / deoxygenation. Shading can cause this ratio to change undesirably during analysis, for example, to more blue / bluish light. In such cases, it is often preferable to omit an analysis for shaded areas rather than perform an incorrect analysis. In the image displayed by a display device and / or in automatically generated log files, "no data" or similar can then be indicated or noted for the shaded area, also to prevent the database in the log files from being corrupted. According to some preferred embodiments,In variants or refinements of embodiments, the radiation emitting device comprises a first radiation emitter configured to emit excitation radiation with a first spectrum, and also a second radiation emitter configured to emit excitation radiation with a second spectrum that differs completely or partially from the first spectrum. For example, the first and / or the second spectrum may be an infrared spectrum, preferably a near-infrared spectrum. Advantageously, at least a portion of the first spectrum and a portion of the second spectrum are detectable by the image capture device. Preferably, changing the at least one property (to generate the different illumination situations) comprisesat least temporarily emit the excitation radiation with the second spectrum alternatively or in addition to emitting the excitation radiation with the first spectrum. The emission of the excitation radiation with the first spectrum and the emission of the excitation radiation with the second spectrum can occur sequentially (optionally, both can also be emitted sequentially and / or simultaneously with the emission of light by the light-emitting device). The excitation radiation with the first spectrum can be emitted, for example, to record a fluorescence signal for normal operation of the device, and the excitation radiation with the second spectrum can be used to detect shadowing. In other words, the excitation radiation with the second spectrum can be used to generate the first and / or second illumination situation.while the excitation radiation with the first spectrum is missing in at least one of the two illumination situations, or in both 10 illumination situations, and is instead used to generate a third illumination situation, which in turn differs from the first and the second illumination situation. 15 According to some preferred embodiments, variants, or refinements of embodiments, the light-emitting device and the excitation-emitting device are configured such that the light emitted by the light-emitting device and the excitation radiation emitted by the 20 excitation-emitting device are emitted onto the medical scene at different exit points and / or with different exit angles. The shadowing detection module is advantageously configured toto calculate the shadowing taking into account the different exit points and / or different exit angles. If the shadowing is detected, for example, based on a changed property of the emitted light from the light-emitting device (e.g., white light), areas are initially detected in which this light is shadowed. However, the actually interesting areas in which the excitation radiation is shadowed may differ from these originally detected areas due to the different exit points and / or exit angles. The shadowing detection module can accordingly include conversion data by means of which the originally detected areas of shadowed light can be converted into the interesting areas of shadowed excitation radiation.wherein these conversion data are based on the known different exit points and / or exit angles. The shadowing detection module can also be configured to perform the conversion using a trained machine learning model, e.g., an artificial intelligence entity such as an artificial neural network. 15 Further advantageous variants, options, embodiments, and modifications will become apparent from the following figures, the detailed description, and the claims. It is to be understood, however, that the detailed description and 20 specific examples, while indicating preferred embodiments of the invention, are provided for illustrative purposes only.since various changes and modifications within the scope of the invention will be apparent to those skilled in the art. 25 Brief Description of the Figures Individual embodiments of the present disclosure will be explained in detail with reference to the following figures. The components in the drawings are not necessarily to scale, but serve to illustrate the principles of the present invention. Parts in the various figures that correspond to the same elements or method steps have been provided with the same reference numerals in the figures. The numbering of method steps initially serves only to distinguish them and does not necessarily imply a corresponding order, although it does represent a variant.to carry out the steps in the order of their numbering. Several steps can also be carried out overlappingly or simultaneously. The figures show: 10 Fig. 1 is a schematic representation of a system according to an embodiment of the present invention; Fig. 2 is another view of a camera head of the system from Fig. 1; Fig. 3 is a schematic representation explaining a shadow detection method that can be carried out by the system from Fig. 1 in a situation without shadowing; Fig. 4 is a schematic representation explaining a shadow detection method that can be carried out by the system from Fig. 1,in a situation with shadowing; Fig. 5 is a schematic flow diagram for explaining a method according to a further embodiment of the present invention; Fig. 6 is a schematic block diagram of a computer program product according to yet another embodiment of the present invention; Fig. 7 is a schematic block diagram of a non-transitory computer-readable data storage medium 30 according to yet another embodiment of the present invention; Fig. 8 is a view of a system according to another embodiment of the present invention; and Fig. 9a is an image representation of a medical scene by a display device superimposing an ICG image on a white light image, without shadowing; Fig. 9b is an image representation of a medical scene by a display device superimposing an ICG image on a white light image,with shadowing; Fig. 9c is a drawn version of Fig. 9a; and Fig. 9d is a drawn version of Fig. 9b. Detailed Description of the Figures Fig. 1 shows a schematic representation of a system 100 15 for detecting shadowing of excitation radiation 12 emitted in the direction of a medical scene 1 according to an embodiment of the present invention. In addition, Fig. 2 shows another view of an illumination and camera head 105 of the system from Fig. 1. The system 100 comprises a light-emitting device 110, which is configured to emit light 11 in the direction of the medical scene 1, which light comprises at least visible light. In the present exemplary embodiment 25, the variant in which the light emitted by the light-emitting device 110 is a white light 11 (i.e., daylight or artificial light simulating natural sunlight) is mainly discussed. It is understood, however,that other types of light can also be emitted, which include at least visible light. The system 100 also comprises an excitation-emission device 120, which is configured to emit the excitation radiation 12 in the direction of the medical scene 1, the shadowing of which is to be detected. The present discussion mainly concerns the variant in which the excitation radiation 12 lies in the spectral range invisible to humans, in particular, an excitation radiation 12 for the excitation of fluorescence in ICG. Specifically, the following example discusses an application in which the excitation radiation 12 in ICG, which is enriched in a tissue, generates an excited radiation 13. For this purpose, a part of the medical scene 1 can be mixed with ICG, for example, an organic tissue of, in,or on a patient. The light emission device 110 and / or the excitation emission device 120 can have a respective or common light or excitation radiation generation device (not shown in Fig. 1). Such generation devices (or light sources) are known in the prior art, for example, the applicant's "POWER LED SAPHIRA" light source (registered trademark), which is capable of generating both the white light 11 and the excitation radiation 12. Light 11 or excitation radiation 12 generated in such a generation device can be guided via a light guide to corresponding emitters, for example, to a combined illumination and camera head 105, as shown in Fig. 1. Furthermore, the system 100 comprises an image acquisition device 130, which is configured to capture images by detecting electromagnetic radiation 13, 15.which comprises a) at least a (preferably visible) portion of the light emittable by the light-emitting device 110 (in particular white light 11), and b) at least a portion of the excited radiation 13 which was excited by the excitation-emitting device 120 (or, more precisely: by the excitation radiation 12 emitted by the excitation-emitting device 120) in the medical scene 1. The image capture device 130 is thus capable of outputting an output signal 79, in particular an image, which is based both on light 15 emanating from the medical scene 1 and based on the white light 11, and on excited radiation 13 emitted by the medical scene 1. It is understood that the visible light 15 emanating from the 15 medical scene 1 may additionally be based on light from sources other than the light emitting device 110 (ie, may be derived therefrom), such as ambient light,Artificial light from lamps or the like. 20 As can be seen in Fig. 2, the system 100 can comprise a combined illumination and camera head 105, in which the light emitting device 110, the excitation emitting device 120, and / or the image acquisition device 130 are fully or partially integrated. The light emitting device 110 and the excitation emitting device 120 can, for example, have adjacent, preferably circular or annular, and concentrically arranged emitters, so that both the white light 11 and the excitation radiation 12 are incident on the medical scene 1 from essentially the same direction. The light emitting device 110 and the excitation emitting device 120 can also—preferably—have the same emitter.to which the light 11 to be emitted or the excitation radiation 12 to be emitted are transported via optical fibers. The light 11 to be emitted and the excitation radiation 12 to be emitted can advantageously be dichroically combined in a light source (common to the light-emitting device 110 and the excitation-emitting device 120) and then emitted via the common emitter. Controlling the light-emitting device 110 and the excitation-emitting device 120 by the control device 140, in particular by the shadowing detection module 145, thus essentially comprises controlling the (common) light source. 15 Likewise, the image capture device 130 can have separate image sensors (e.g. CCD sensors, CMOS sensors or the like), in particular a first image sensor 131 for white light incident from the medical scene 1, originating entirely or partly from the light emission device 110,and a second image sensor 132 for the excited radiation 13. The first image sensor 131 and the second image sensor 132 can also be arranged concentrically, as indicated in Fig. 2. The first image sensor 131 and the second image sensor 132 can also be integrated into one another, or even be identical to one another, with a distinction being made on the evaluation side, e.g., by software and / or correspondingly synchronized in time (in the case of sequentially emitted different electromagnetic radiation). The arrangement of the first and second image sensors 131, 132 as well as the arrangement of the light emission device 110 and the excitation emission device 120 can in turn be arranged adjacent to one another, for example, in the form of two substantially tangent circles, as shown in Fig. 2. Again with reference to Fig. 1, the system 100 also comprises a control device 140, which is configured toto control the light emission device 110 and the excitation emission device 120, in particular a respective switching on and off, but also, for example, respective emission powers, optionally also the wavelength spectrum, and / or the like. The control device 140 also has a shadowing detection module 145, which is configured to carry out a shadowing detection method, which will be explained in more detail below, particularly with reference to Fig. 3 and Fig. 4. In the situation schematically illustrated in Fig. 3, the case of "no shadowing", N, applies. The medical scene 1 contains an instrument 2, which could potentially shadow an area therein,but does not do so. As a result, both the light 11 emitted by the light-emitting device 110 and the excitation radiation 12 reach the entire 25 medical scene 1 without shadowing. The situation schematically illustrated in Fig. 4 represents the "shadowing" case, Y. The medical scene 1 contains an instrument 2, which creates a shadowed 30 area 5 into which neither the light 11 from the light-emitting device 110 nor the excitation radiation 12 from the excitation-emitting device 120 reach. The shadow detection method can in particular comprise the following steps a)-f): a) Controlling the light emission device 110 and the excitation emission device 120 such that they emit the light, in particular white light 11, and the excitation radiation 12, simultaneously onto the medical scene 1 in order to generate a first illumination situation 21 (see Fig. 3,10 top left): The first lighting situation 21 can in particular be the, or a, standard lighting situation, i.e., a lighting situation that prevails predominantly during normal operation of the system 100. If the system 15 is, for example, an endoscope or exoscope system, the standard lighting situation can be one that a user sets during normal operation of the endoscope or exoscope, i.e., for example, in which an operation or diagnosis is carried out. 20 b) Controlling the image capture device 130 such that it captures an image of the medical scene in the first lighting situation 21 in order to generate a first comparison image 31: To generate the first comparison image 31, the image capture device 130 advantageously captures white light 15 originating from the medical scene 1 (e.g., due to reflection, scattering, refraction, diffraction,...) as well as the radiation 13 excited in the medical scene 1 by the excitation radiation 12. In the present example, the first comparison image 31 is a "visible image" or "white light image," i.e., an image recorded in the range visible to the human eye. The first comparison image 31 can, for example, be an RGB image, i.e., an image generated using three photosensor types, each responsible for either red, green, or blue light, i.e., with three color channels. c) Controlling the light-emitting device 110 and / or the excitation-emitting device 120 such that it changes at least one property of the emitted light 11 or the emitted excitation radiation 12, respectively, compared to the first illumination situation 21, in order to generate a second illumination situation 22 (see Fig. 3, top right): As already explained in detail above,This change in at least one property can be implemented in a variety of ways, for example, as a change in the emission spectrum of the light-emitting device 110 and / or the excitation-emitting device 120, by a change in the emission power of the light-emitting device 110 and / or the excitation-emitting device 120, and the like. The case described here is an example in which the emission power of the light-emitting device 110 is reduced, as indicated in Fig. 3 at the top right by the thinner arrow of the white light 11. Particularly when the first lighting situation 21 is a standard lighting situation, it is advantageous if the second lighting situation 22 only exists for a shorter period of time than the first lighting situation 21, for example, only 1 / 10 of the time, or 1 / 20 of the time.or 1 / 30 of the time or less than the first lighting situation 21. For example, the second lighting situation 22 can be generated for a period of 16 milliseconds, e.g., once per second, while the first lighting situation 21 is present for the rest of the time. An optional analysis (or evaluation) of the 5 images acquired by the image acquisition device 130 is preferably performed only during the first lighting situation 21. d) Controlling the image acquisition device 130 such that it acquires an image of the medical scene in the second lighting situation 22 to generate a second comparison image 32: In the present example, the second comparison image 32 is also a "visual image" or "white light image." However, it is understood that the type of comparison images is related to the respective property,which is changed to create the second illumination situation 22. If the change in the property comprises a change in a wavelength spectrum or, for example, a change in the emission power of invisible excitation radiation, the comparison images 31, 32 are recorded in such a way that the change can be visible therein, for example in the form of multi- or hyperspectral images. 25 e) Detecting a shadowing of the excitation radiation emitted in the direction of the medical scene by comparing the first comparison image 31 with the second comparison image 32: In the situation schematically illustrated in Fig. 3 30, the case of "no shadowing", N, is present. By comparing the first comparison image 31 with the second comparison image 32, it can be seen that by reducing the emission power of the light emission device 110 in the second comparison image 32, the entire medical scene 1 is changed, here: darker,Accordingly, the light 11 from the light emission device 110 reaches the entire medical scene 1, and the shadowing detection module 145 accordingly determines that the excitation radiation 12 from the excitation emission device 120 also reaches the entire medical scene 1. Thus, the shadowing detection module 145 determines "no shadowing", N, of the excitation radiation 12. f) Outputting an output signal 79, which at least 15 indicates whether shadowing is present: This means that at least YES / NO or Y / N information is output. In the situation illustrated with reference to Fig. 3, the information "NO", i.e., "no shadowing" N is present, would be sufficient, for example. 20 Fig. 4, in contrast to Fig. 3, represents the case where shadowing, Y, actually exists.of the area 5 of the medical scene 1 by the instrument 2. Fig. 4, top left, again shows the generation of the first 25 lighting situation 21 and the acquisition of the first comparison image 31, and Fig. 4, top right, again shows the generation of the second lighting situation 22 and the acquisition of the second comparison image 32. 30 The sequence a)-f) is identical in this situation, except that the comparison of the comparison images 31, 32 in step e) now reveals that there is a difference: the shadowed area 5 has not changed, while the remaining medical scene 1 has changed in the second comparison image 32. From this, the shadowing detection module 145 concludes that the change in the lighting situation 21, 22 has no influence on the shadowed area 5 and thus there is no illumination of this area by the light-emitting device 110, which suggests thatthat this area is also not illuminated by the excitation radiation 12. Accordingly, the shadowing detection module 145 concludes that shadowing, Y, is present. In particular, for this case, it is preferred if the output signal 79 contains additional information, such as a time of shadowing, a spatial extent of the shadowing, (particularly preferably) the exact position of the shadowed area 5, and / or the like. When comparing the comparison images 31, 32 in step e) 20, it is understood that the comparison is carried out ceteris paribus, i.e., any other changes that have occurred between the acquisition of the first comparison image 31 and the acquisition of the second comparison image 32, but are not due to the changed lighting situation 21, 22 or 25, at least not due to the changed property of the light-emitting device 110 and / or the excitation-emitting device 120,be excluded from the comparison. For example, automatic brightness control of the light emission device 110 / excitation emission device 120 can be provided. If the overall brightness changes between the acquisition of the two comparison images 31, 32, the change in the overall brightness can be calculated out for the comparison. For example, the comparison images 31, 32 can each be normalized to the overall brightness prevailing at the time of acquisition. 5 In particular, a change (e.g., reduction) in emission power can be accompanied by a frame-synchronous change in the exposure control of the image acquisition device 130 (more precisely: a corresponding image sensor 131, 132), e.g., such that the overall brightness of the respective comparison image recorded remains constant.and only noise and shadowed areas cause a change in brightness. In general, the control device 140, in particular the shadow detection module 145, can advantageously provide synchronous control 15 of the light emission device 110 and the excitation emission device 120 on the one hand, and of the image acquisition device 130, in particular one or more image sensors 131, 132, on the other hand (or, more simply expressed: between the light / radiation sources on the one hand and the camera on the other). As already explained above, the system 100 preferably has a display device 150, by means of which the image data acquired by the image acquisition device 130 are displayed, delayed or in real time, in an image 51. The modes commonly used for known endoscopes or exoscopes can be used here, e.g., display of true colors (visual image / white light image),Display of false colors due to wavelengths invisible to humans, a superposition of both (for example: ICG overlay display), switchability between multiple modes, and so on. The image capture device 130 is often designed to generate multispectral images (multiple discrete wavelengths or disjoint wavelength ranges are captured, typically 4 or more) or hyperspectral images (a continuum of 5 wavelengths is captured). In these cases, the image capture device 130 can also be referred to as a multispectral camera or hyperspectral camera. The display device 150 can then, for example, display a false color representation of a recorded infrared spectrum or the like. It is particularly advantageous if, in the image 51, which is based (exclusively or among other things) on the radiation 13 excited by the excitation radiation 12, the output signal 79 is displayed,in which area 5 the excitation radiation 12 is currently shadowed. Thus, a user viewing the display device 150 immediately knows that he is not currently seeing an image 51 corresponding to the actual situation. The display of the shadowed area 5 by the display device 150 can be done by a border (similar to that shown schematically in Fig. 9b), by an overlay with a semi-transparent colored area, or the like. 25 Since the shadowing of the excitation radiation 12 is often (or, as in the example discussed here with reference to Fig. 3 and Fig. 4, inevitably) accompanied by a shadowing of the light 11 emitted by the light emission device 110, this means that the shadowed area 5 30 is often darker than desired even in a white light image. Therefore, it can also be provided that an area 5 in which a shadowing Y was detected,is digitally brightened by the display device 150. For example, in a white light mode, the display device 150 can display the captured medical scene 1 in the usual way based on white light 115. However, if the user switches the display device 150 to a mode in which the image 51 is at least partially based on the excited radiation 13 (e.g., an overlay mode or a false color mode), the display device 150 can indicate, based on the output signal 79, 10, in which areas 5 of the image 51 is currently incorrect. The control device 140 can optionally, as also schematically shown in Fig. 1, have a compensation module 15147, which is configured to replace at least the area 5 in which the excitation radiation 12 is shaded, in the image 41 displayed by the display device 150, with substitute image data.while the excitation radiation 12 is shadowed therein. The 20 substitute image data can be generated, in particular, on images (or frames) previously acquired by the image acquisition device 130, in particular based on previously acquired images (or frames) for which no shadowing N was detected, at least in the area for which the substitute image data is generated. Instead of just the shadowed area, it can also be provided that the entire image is replaced, which can be advantageous if movements / shape changes of the shadowed area 5 occur within the medical scene 1. 30 However, it can also be provided that the substitute image data are generated by a temporal averaging of the last 2 to 180 acquired images (or frames). Since the tissue 3 of interest and the image acquisition device 130 can be quite static, while, for example, instruments 2 are frequently moved,In this way, the shadowing 5 caused by an instrument 2 can already be masked out in many cases. The images from multi- or hyperspectral cameras are also frequently used to perform further analyses thereon, which can provide the user with additional information 10. The control device 140 can, as schematically shown in Fig. 1, have an analysis module 160 which performs such analyses, i.e., which in particular performs an analysis of the images captured by the image capture device 130 based on their spectral properties 15. In order to ensure that such analyses are not compromised or rendered useless by shadowed areas 5, it can be provided that the analysis module 160 is configured to exclude any areas 5 in which the excitation radiation 12 is shadowed from the analysis 20. The case was described above,that a change in the emission power of the white light 11 emitted by the light-emitting device 110 is used to detect the shadowed areas 5. In the exemplary embodiment described above, the white light 11 (as an example of a fully or partially visible electromagnetic radiation) was always emitted simultaneously with the excitation radiation 12. 30 In further variants, the light from the light-emitting device 110 (in particular white light 11) and the excitation radiation 12 can also generally be emitted sequentially, or at least for the detection of the shadowing, for example for fluorescence imaging in the visible range. In these variants, the two illumination situations 21, 22 can be illumination situations 5 in which exclusively light or white light 11 is emitted, in particular exclusively by the light-emitting device 110. This is particularly advantageouswhen the light-emitting device 110 and the excitation-emitting device 120 emit the light / white light 11 or the excitation radiation 12 through the same emitter, i.e., at the same exit point, so that there is only a temporal, but no spatial, offset between the emission of white light 11 and the excitation radiation 12. A shadowing of the white light 11 thus directly corresponds to a shadowing of the excitation radiation 12. It is thus possible both for the (normal) operation of the imaging device, e.g., the endoscope or exoscope, for light (in particular white light 11) and the excitation radiation 12 to be emitted sequentially, i.e., alternately, and for the light 11 and the excitation radiation 12 to be emitted simultaneously. Independently of this, the shading detection method can again be set up so that the first 25 and / or the second lighting situation 21,22 by exclusively illuminating the medical scene 1 with light (in particular white light 11), by exclusively illuminating the medical scene 1 with excitation radiation 12, and / or by simultaneously illuminating the medical scene 1 with both light (in particular white light 11) and excitation radiation 12. Fig. 3 and Fig. 4 also illustrate a method according to an embodiment of the second aspect of the present invention, i.e., a method for detecting a shadow Y of excitation radiation 12 emitted in the direction of a medical scene 1. Fig. 5 additionally shows a schematic flow chart to further explain this method. The method can in particular (but does not necessarily have to) be carried out by the system 100 according to the invention. Therefore, the method according to the invention can be implemented according to all variants described with reference to the system 100,Options, embodiments, and refinements can be adapted and vice versa. To avoid duplication, particular reference is made to the preceding description of method steps a)-f) of the shadow detection method performed by the shadow detection module 145, which largely proceed in the same way. 20 In the method, in a step S10, light 11, which comprises at least visible light, is emitted onto the medical scene 1 simultaneously, as is excitation radiation 12, in order to generate a first illumination situation 21. As a result, the excited radiation 13 (in particular invisible electromagnetic radiation) and reflected light 15 (in particular visible light, e.g., white light) can emanate from the medical scene 1. 30 In a step S20, an image of the medical scene 1 in the first illumination situation 21 is captured.to generate a first comparison image 31. In a step S30, at least one property of the emitted light 11 and / or the emitted excitation radiation 12 is changed compared to the first illumination situation 21 of the medical scene 15 in order to generate a second illumination situation 22 of the medical scene 1. In a step S40, an image of the medical scene 1 in the second illumination situation 22 is captured in order to generate a second comparison image 32. In a step S50, a shadow Y of the excitation radiation 12 emitted in the direction of the medical scene is detected by comparing the first comparison image 31 with the second comparison image 32, or, in other words, the first and second comparison images 31, 32 are compared with one another in order to detect a shadow Y or no shadow N. 20 In a step S60, an output signal 79 is output which at least indicateswhether the excitation radiation 12 emitted in the direction of the medical scene 1 is shadowed in any area 5. As already explained several times, the output signal 79 can further comprise further information, preferably further information about the shadowed area 5, particularly preferably information about the position of the shadowed area 5. 30 In a step S70, an image 51 of the medical scene 1 can be displayed, for example by a display device 150, in which image any shadowed area 5 is additionally visually marked, for example by a border, overlay with a colored or patterned area, digital brightening of the area 5 and / or the like. 5 In a step S80, an analysis of the images captured by the image capture device 130 can be performed, in particular based on their spectral properties,wherein the shadowed regions 5 are preferably excluded from the analysis, at least if the analysis to be carried out is based on electromagnetic radiation (light 11 or the excitation radiation 12) which is currently shadowed in the region 5. Fig. 6 shows a schematic block diagram of a computer program product 200 according to an embodiment of the third aspect of the present invention. The computer program product 200 comprises executable program code 250 which, when executed (e.g., by a computing device), is configured to carry out the method according to an embodiment of the present invention, for example, according to Figs. 3 to 5. Fig. 7 shows a schematic block diagram of a non-transitory computer-readable data storage medium 300 according to an embodiment of the present invention. The data storage medium 300 comprises executable program code 350 which is configured towhen executed (e.g., by a computing device), to carry out the method according to an embodiment of the present invention 30, for example, according to Fig. 3 to Fig. 5. The non-volatile computer-readable data storage medium 300 can, for example, be designed as a semiconductor memory, e.g., an SSD memory chip, or comprise such a memory. The data storage medium 300 can also comprise or comprise a CD, DVD, Blu-ray, or a magnetic storage device. 5 Fig. 8 shows an overview view of a system 100 according to a further embodiment of the present invention. In Fig. 8, the system 100 comprises a mobile frame 170, on which the remaining components of the system 100 are arranged. The light emission device 110 and the excitation emission device 120 are designed as an adjustable,after adjustment, a static LED array is formed or integrated into such. The image capture device 130, in particular a hyperspectral camera, is arranged in the geometric center of the LED array. The system 100 from Fig. 8 can thus also be referred to as an open-surgery hyperspectral camera system. The above description of the disclosed embodiments contains only examples of possible implementations, which are described in order to enable a person skilled in the art to manufacture or use the present invention. Various variations and modifications of these embodiments will be readily apparent to a person skilled in the art, given knowledge of the present invention, and the general principles defined herein can be applied to other embodiments without departing from the scope of the present disclosure. Thus, the present invention is not intended to be limited to the embodiments shown herein.specific embodiments, but should be granted the broadest scope consistent with the principles and novel features disclosed herein. Therefore, the present invention is to be limited only in accordance with the following claims. 5 The invention can be roughly summarized as follows: A system 100 and a method for detecting shadowing of excitation radiation 12 emitted in the direction of a medical scene 1 are provided. 10 For this purpose, comparison images 31, 32 are recorded under different lighting situations 21, 22, which are compared with each other. The lighting situations 21, 22 are selected such that they must be different when shadowing, Y, is present, and must be the same when no shadowing, N, is present. If shadowing, Y, is present, various measures can be taken,for example, a changed representation of the shaded area 5 in the image 51 of a display device 150, a changed evaluation by an analysis module 160 and / or 20 the like.

[0002] List of reference symbols ^ 1 Medical scenery 2 Instruments 5 3 Tissue to be inspected 4 Section with marker 5 Shadowed area in the medical scenery 11 White light 12 Excitation radiation 10 13 Excited radiation 15 Light emanating from the medical scenery 21 First illumination situation 22 Second illumination situation 31 First comparison image 15 32 Second comparison image 51 Displayed image 79 Output signal 100 System 105 Illumination and camera head 20 110 Light emission device 120 Excitation emission device 130 Image acquisition device 131 First image sensor 132 Second image sensor 25 140 Control device 145 Shadow detection module 147 Compensation module 150 Display device 160 Analysis module 30 170 Frame 200 Computer program product 250 Program code 300 Data storage medium 350 Program code N no shadowing is present S10..S80 5 process steps Y shadowing is present

Claims

Claims 1. System (100) for detecting a shadow (Y) of excitation radiation (12) emitted in the direction of a medical scene (1), comprising: a light emission device (110) which is configured to emit light (11) in the direction of the medical scene, which light comprises at least visible light; an excitation emission device (120) which is configured to emit the excitation radiation (12) in the direction of the medical scene (1); an image capture device (130) which is configured to capture images by detecting electromagnetic radiation (13, 15) which comprises a) at least a portion of the light (11) emittable by the light emission device (110) and b) at least a portion of excited radiation (13) which was excited by the excitation emission device (120) in the medical scene;a control device (140) which is designed to control the light emission device (110) and the excitation emission device (120), wherein the control device (140) has a shadowing detection module (145) which is designed to carry out a shadowing detection method which has the steps of: 0 - controlling the light emission device (110) and the excitation emission device (120) such that they emit the light (11) and / or the excitation radiation (12); emit the medical scene (1) (S10) to generate a first lighting situation (21); - controlling the image capture device (130) such that it captures an image of the medical scene 5 in the first lighting situation (21) (S20) to generate a first comparison image (31); - controlling the light emission device (110) and / or the excitation emission device (120) such that it changes at least one property of the emitted light (11) or of the emitted excitation radiation (12) compared to the first lighting situation (21) (S30) to generate a second lighting situation (22); - controlling the image capture device (130) such that it captures an image of the medical scene in the second lighting situation (22) (S40) to generate a second comparison image (32);- detecting (S50) a shadowing of the excitation radiation emitted in the direction of the medical scene by comparing the first comparison image (31) with the second comparison image (32); and - outputting (S60) an output signal (79) which at least indicates whether a shadowing is present. 5 2. System (100) according to claim 1, wherein the excitation radiation (12) and / or the excited radiation is invisible electromagnetic radiation. 0 3. System (100) according to claim 1 or 2, wherein the at least one changed property is an emission power of the light emitted by the light emission device (110); (11), and wherein changing this property comprises, in particular, reducing the emission power.

4. The system (100) according to one of claims 1 to 3, wherein the shadow detection module (145) is configured to perform the shadow detection method regularly and / or on request.

5. The system (100) according to one of claims 1 to 4, wherein the light (11) emittable by the light-emitting device (110) and the excitation radiation (12) emittable by the excitation-emitting device (120) are disjoint in the electromagnetic spectrum, and can optionally be emitted simultaneously, in particular by a common light source of the light-emitting device (110) and the excitation-emitting device (120). 6.System (100) according to one of claims 1 to 5, wherein the system (100) has a display device (150) 0 which is configured to display an image (51) which is based on the output signal (79) and on an image currently acquired by the image acquisition device (130), in particular in real time. 5 7. System (100) according to one of claims 1 to 6, wherein the output signal (79) comprises information about an area (5) in the medical scene in which the excitation radiation (12) is shaded, if such an area (5) is present. 0 8. System (100) according to claim 6 or claims 6 and 7, wherein the display device (150) is configured to display the area (5) in which the excitation radiation (12). is shaded, visually mark in the image currently acquired by the image acquisition device (130). 5 9. System (100) according to claim 8, wherein the system (100) further comprises a compensation module (147) which is configured to replace the region (5) in which the excitation radiation (12) is shaded, in the image (51) displayed by the display device (150), with substitute image data while the excitation radiation (12) is shaded therein.

10. System (100) according to claim 9, wherein the substitute image data are generated based on images previously acquired by the image acquisition device (130), in particular based on previously acquired images for which no shadowing (N)0 was detected at least in the region for which the substitute image data are generated.The system (100) according to claim 10, further comprising an analysis module (160) configured to perform an analysis of images acquired by the image acquisition device (130) based on their spectral properties, and further configured to exclude any regions (5) in which the excitation radiation (12) is shadowed from the analysis.

12. The system (100) according to any one of claims 1 to 11. wherein the radiation emission device (120) has a first radiation emitter (122) configured to emit excitation radiation (12) with a first spectrum, and a second radiation emitter (124) configured to emit excitation radiation (14) with a second spectrum that differs completely or partially from the first spectrum, and wherein at least a portion of the first spectrum and a portion of the second spectrum are detectable by the image capture device (130); wherein changing (S30) the at least one property comprises at least temporarily emitting the excitation radiation (14) with the second spectrum alternatively or in addition to emitting the excitation radiation (12) with the first spectrum.Device (100) according to one of claims 1 to 12, wherein the light emission device (110) and the excitation emission device (120) are configured such that the light (11) emitted by the light emission device (10) and the excitation radiation (12) emitted by the excitation emission device (120) are emitted onto the medical scene (1) at different exit points and / or with different exit angles, and wherein the shadowing detection module (145) is configured to calculate the shadowing taking into account the different exit points and / or different exit angles.

14. A method for detecting a shadow (Y) of excitation radiation (12) emitted in the direction of a medical scene (1), comprising: - emitting (S10) light (11), which comprises at least visible light, and / or excitation radiation (12) onto the medical scene in order to generate a first lighting situation (21); - capturing (S20) an image of the medical scene (1) in the first lighting situation (21) in order to generate a first comparison image (31); - changing (S30) at least one property of the emitted light (11) and / or of the emitted excitation radiation (12), compared to the first lighting situation (21), in order to generate a second lighting situation (22); - capturing (S40) an image of the medical scene (1) in the second lighting situation (22) in order to generate a second comparison image (32);- detecting (S50) a shadowing (Y) of the excitation radiation (12) emitted in the direction of the medical scene (1) by comparing the first comparison image (31) with the second comparison image (32); and - outputting (S60) an output signal (79) which at least indicates whether the excitation radiation (12) emitted in the direction of the medical scene (1) is shadowed in any area.

15. A computer program product (200) comprising executable program code (250) which, when executed, is designed to carry out the method according to claim 14.; 16. A non-transitory, computer-readable data storage medium (300) comprising executable program code (350) which, when executed, is designed to perform the method according to claim 14. 5

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