Securing a dedicated scanning operation

Abstract

A method for dedicated medical imaging is described. In the method, medical measurement data (RD, BD) are acquired from an examination area (UB) of a patient (P). Image recognition is performed automatically based on the acquired medical measurement data (RD, BD). Finally, a release decision concerning medical image data (BD) generated based on the medical measurement data (RD, BD) is made automatically based on the image recognition. A monitoring device (40) is also described. Furthermore, a medical imaging system (10) is described.

Description

The invention relates to a method for dedicated medical imaging. The invention also relates to a monitoring device. The invention further relates to a medical imaging system.Medical imaging systems, in particular magnetic resonance imaging systems and computed tomography systems, can be used both for whole-body imaging and for imaging specific individual body regions or body parts.One concept which deals with the most efficient possible operation of medical imaging systems relates to the use of dedicated medical imaging systems which have a restricted field of application. Such a limited range of applications is determined, for example, by the geometry and dimensions of the interior of a medical imaging system. If a medical imaging system is intended to image only a specific group of body parts and not to allow full-body imaging at all, this limitation can be achieved by limiting the dimensions of the patient opening of the medical imaging system. For example, an MR system (MR system is an abbreviation for "magnetic resonance imaging system") with a small bore diameter (i.e., a diameter of the patient opening) can be designed such that it does not allow the placement of the entire thorax or abdomen of a patient, but only the placement of extremities, i.e., in particular the knees, the foot, the wrist or the elbow and possibly also the head of a patient.In particular, a magnetic resonance imaging system can also be configured such that the patient opening allows the entire patient to be placed, but only has a small homogeneity volume of the applied B 0- field, so that not the entire upper body or the entire head of the patient can be imaged with sufficient quality, but only a part thereof and the magnetic resonance imaging system is thus likewise suitable only for imaging the extremities.However, both restrictions can be partially bypassed. The restricted dimensions of the patient opening can be avoided, for example, in the case of particularly small or slender patients. Also, a medical imaging system that is permitted for imaging a specific body part can be easily used for imaging another body part whose dimensions are similar.For example, an MR system, which is to be used only for dental imaging, can also be used for other body regions with certain restrictions on the basis of the protocols and contrasts specific for this purpose. It could be used for the imaging of extremities, for example, although the MR system is not designed for this application.This misuse of the respective medical imaging system leads to a reduced image quality and thus to a reduction in the quality of medical processes, in particular the diagnosis and treatment of patients. Such a disadvantageous development can be incorrectly used in the extreme case to the manufacturer who could not prevent such "abuse".A limitation of a medical imaging system to dedicated applications can be achieved, for example, by setting up an interface which limits the use of the medical imaging system to predetermined applications. This restriction can be achieved in that the sequences and protocols provided for the imaging cannot be freely parameterised and also cannot be freely selected, but instead only fixed workflows or workflows are predefined. In this way, abuse of the medical imaging system can be made more difficult. For example, the workflows are optimized for dental imaging and can be used only to a limited extent for other body parts, such as the elbow. However, users with low demands could nevertheless not be prevented from using the medical imaging system for other body parts. For example, a scanning unit intended for head imaging can also be "abused" for knee imaging.Thus, there is a problem of ensuring the use of dedicated medical imaging systems and preventing intended or unintentional misuse.This object is achieved by a method for dedicated medical imaging according to claim 1, by a monitoring device according to claim 12 and by a medical imaging system according to claim 13.In the method according to the invention for dedicated medical imaging, medical measurement data from an examination region of a patient are acquired. The medical measurement data is received by a medical imaging system. The medical measurement data can comprise raw data and / or image data. The medical measurement data can comprise raw data and / or image data from the actual examination; they can also comprise so-called pre-recording data, i.e. so-called prescan data. The medical imaging system is designed by hardware specification and / or software specification for one or more particular types of imaging or for imaging one or more particular body regions.An automated performance of an image recognition is then carried out on the basis of the acquired medical measurement data. The image recognition comprises a determination of content information relating to the measurement data or image data generated therefrom. The image recognition makes it possible to identify image regions and / or partial image regions. Preferably, the entire examination region is recognized as a region of a specific body part, for example as a knee region, or a partial region of the examination region is segmented and identified, for example identified with a specific body part or organ.As will be explained in detail later, this automated image recognition can be carried out by an automated comparison with reference data, but it can also be carried out by a model trained on training data or another type of automated pattern recognition.Finally, on the basis of the image recognition, an enabling decision is automatically made, which relates to generated medical image data based on the medical measurement data. If the result of the image recognition is positive, i.e. it is determined that the generated medical image data corresponds in content to the use specifications of the medical imaging system, the generated medical image data is released and can then be displayed to the user. However, if it is determined during the image recognition that the generated medical image data do not fall within the enabled use range in terms of content, they are either not enabled at all and are thus not displayed to the user or they are displayed to a limited extent, i.e. preferably only a partial region of the examination region is displayed which is compatible in terms of content with enabled use of the medical imaging system or the image data are displayed with reduced quality, so that they are only usable to a limited extent, for example as a overview image, but not for a diagnosis or diagnosis. Advantageously, dedicated imaging is achieved, which is limited in content to a predetermined restricted use range. In particular, the medical imaging system cannot be used for purposes. For example, an imaging system for imaging the arms cannot be used for imaging the head or teeth. For example, a dentist is prevented from "lending" an imaging system from an adjacent orthopedic person and from themselves purchasing or rentaling an imaging system. Also, misdiagnoses due to misdiagnosis imaging that provides qualitatively insufficient images are possibly avoided.The monitoring device according to the invention has an input interface for receiving medical measurement data from an examination region of a patient from a medical imaging system. Part of the monitoring device according to the invention is an image recognition unit for automatically carrying out image recognition on the basis of the received medical measurement data. The monitoring device according to the invention also comprises an enabling unit for automatically making an enabling decision relating to generated medical image data based on the medical measurement data on the basis of a result of the image recognition. The monitoring device according to the invention shares the advantages of the method according to the invention for dedicated medical imaging.The medical imaging system according to the invention, preferably a magnetic resonance imaging system or a computed tomography system, has a scanning unit for acquiring medical measurement data from a patient and a monitoring device according to the invention, with which the medical measurement data recorded by the scanning unit are analyzed and medical image data generated on the basis thereof are released, if appropriate. The medical imaging system according to the invention shares the advantages of the monitoring device according to the invention.The medical measurement data can comprise magnetic resonance signals or be based on such signals, for example. Depending on the medical imaging system used for acquiring the medical measurement data, however, other medical measurement data typical for the respective medical imaging system are also conceivable.A large part of the aforementioned components of the monitoring device according to the invention can be realized wholly or partly in the form of software modules in a processor of a corresponding computing system, for example by a computing system in a medical imaging system. A realization largely through software has the advantage that even previously used computing systems can be easily retrofitted with a software update in order to operate in the manner according to the invention. In this respect, the object is also achieved by a corresponding computer program product having a computer program which can be loaded directly into one or more computing systems, having program sections in order to carry out the steps of the method according to the invention for dedicated medical imaging, in particular the steps for automatically carrying out image recognition and for automatically making an enabling decision, when the program is executed in the computing system or systems. In addition to the computer program, such a computer program product can optionally comprise additional components such as documentation and / or additional components, also hardware components such as hardware keys (dongles, etc.) for using the software.For transport to the computing system and / or for storage on or in the computing system, a computer-readable medium, e.g. a memory stick, a hard disk or another transportable or permanently installed data carrier, can be used, on which the program sections of the computer program that can be read in and executed by a computing system are stored. For this purpose, the computing system can have one or more cooperating microprocessors or the like, for example.The dependent claims and the following description each contain particularly advantageous embodiments and further developments of the invention. In this case, in particular, the claims of one claim category can also be developed analogously to the dependent claims of another claim category. In addition, within the scope of the invention, the various features of different exemplary embodiments and claims can also be combined to form new exemplary embodiments.As already mentioned briefly, the medical measurement data preferably comprise raw data and / or image data and / or pre-recording data. Pre-picture data can be generated at a lower resolution than the image data of the main picture. Such pre-recording data are preferably obtained by a navigator measurement or during the recording of projection image data. Raw data comprise unprocessed measurement data which are acquired from an examination region during medical imaging. In the case where a computed tomography system is used as the imaging modality, raw data comprise projection data which are converted into image data by a filtered back projection. As already mentioned, the unprocessed measurement data comprised by the raw data can also comprise magnetic resonance signals or k-space data for the case where a magnetic resonance imaging system is used as the imaging modality. All available data from the examination region of a patient can advantageously be used for image recognition, so that a broad data basis is provided for image recognition. If the raw data are used for the image recognition, an image reconstruction can be omitted if it is already clear on the basis of the analysis of the raw data that the image recording is not malicious and should not be displayed.As likewise already briefly indicated, the image recognition can be carried out on the basis of the following image recognition methods:a comparison of the medical measurement data with previously known reference measurement data,automated pattern recognition based on the acquired medical measurement data,an image data recognition based on an AI-based model (AI stands for "artificial intelligence"), which is applied to the medical measurement data.In a comparison, the medical imaging system may include a reference database that stores reference image data or reference measurement data associated with specific body regions and / or organs to be identified within the scope of image recognition.Automated pattern recognition may be based on syntactic and / or statistical and / or structural pattern recognition.An image data recognition based on an AI-based model can be trained by training data to recognize image information on the basis of the measurement data. Once the model has been trained, reference data need no longer be used for the image recognition itself.Preferably, in the step of image recognition of the method according to the invention, an organ located in the examination region or a body region comprising the examination region is recognized. The recognized body region or the recognized organ can now advantageously be compared with data from a database which stores and specifies organs or body regions permitted for imaging. The data of this database can be adapted to its specific field of application before a medical imaging system is transferred to the customer. If the customer later acquires additional licenses because he wishes to expand his field of application, further organs or body areas can be stored in the database and thus licensed. In conjunction with the extension of the field of application of the medical imaging system, specific software packages, which preferably comprise specific workflows, specific sequences and specific contrasts, can also be enabled. A specific image filter can also be adapted. Advantageously, additional areas of application for its medical imaging system can be released to the customer as required.The clearance decision is therefore preferably made on the basis of specification data of a database which stores specification data for examination regions permitted for clearance. Such specification data comprise information about specific subareas of the human body that are enabled for imaging, in particular the head area, the torso area or the arms or legs. In detail, the specification data can also release individual functional units or organs of the body or of the mentioned subareas, such as, for example, the jaw in the head area, the knee in the leg area, the liver, the heart, etc., as specific organs to be imaged.In one embodiment of the method according to the invention for dedicated medical imaging, classification of the acquired medical measurement data and / or the generated medical image data is carried out on the basis of the image recognition, and the clearance decision is made as a function of the classification of the acquired medical measurement data and / or the generated medical image data. Thus, in particular only generated medical image data with a predetermined classification are enabled. Advantageously, the recorded medical image data can be assigned to a known type of image data via the classification and the subsequent comparison of this type with permitted types of image data can be carried out in order to find out whether or not the captured image data are to be released.The classification preferably comprises an assignment of the generated medical image data to a specific type of an examination region, in particular to a specific body region, and the enabling decision is made as a function of the assigned type of the examination region. Thus, in particular only medical image data from one or more predetermined body regions is enabled. Advantageously, only the position of the image recording in the body has to be determined as a basis for a clearance decision. The position can be determined, for example, by comparison with image data whose position in the body is known.The enabling decision preferably also comprises enabling the medical image data with restricted image quality as a function of a result of the image recognition carried out. Instead of a binary decision which comprises only a complete suppression of the release of image data or a complete release, the release decision can comprise, in addition to these two options, also the possibility of a decision that medical image data are released only with limited image quality. The release of medical image data with limited quality depending on a result of the performed image recognition can, however, also be used within the framework of a binary decision scheme if only either a complete release of the image data or a release of medical image data with limited quality are to be selected as possible options. Advantageously, on the basis of the medical image data with limited quality, an overview of a body region can be obtained, in particular for detecting a specific body structure, in particular a specific organ or a specific functional unit. Advantageously, a user can obtain at least one overview image, but without obtaining sufficient information for a reliable diagnosis or diagnosis. Advantageously, the user is informed that the imaging has been carried out successfully without the recorded image data being "abused". For the reduction of the image quality, a downstream filter algorithm is preferably used, with which the generated image data, which have a high quality, is caused to be reduced in quality by a filter before being output.The enabling with limited image quality preferably comprises enabling the medical image data with reduced resolution and / or enabling the medical image data with reduced matrix size. The term "resolution" is intended to mean the image sharpness or image size of a raster graphic. It is indicated by the total number of pixels or by the number of columns and rows of the raster graphics. The term "matrix size" refers to the number of pixels or the number of columns and rows of an X-ray image or a slice of a CT image or magnetic resonance image. Advantageously, the usability of the image data is greatly limited by the reduction of the image quality or image information density, and thus an abuse of image data is prevented.A restricted release is preferably effected on the basis of the image recognition of only a predetermined number of image recordings. For example, the generated medical image data is classified as image data of the extremities of a patient. If the user has now acquired only one license for a limited number of image recordings, for example 100 image recordings from the extremities of a patient, then after this limit has been exhausted, either no image data at all or only image data that have been reduced in quality are output and the user must first renew his license until he can continue to use his medical imaging system. By identifying individual body regions or organs within the scope of a so-called pay-per-use model, an individual use of the imaging system for a specific body region can also be specifically calculated.Preferably, in the event that no release is issued, one of the following additional measures takes place:an interruption of the imaging takes place,an error message is output,the medical imaging system is deactivated for a predetermined period of time,the patient is removed automatically from the medical imaging system.Advantageously, it is unambiguously indicated to the user, either by communication or by setting the operation, that an abuse of the medical imaging system is not accepted.The medical imaging system is preferably restricted to predetermined body regions by structural measures. Advantageously, "abuse" of the medical imaging system can be at least made more difficult already by its technical design. For example, dimensioning the patient opening or restricting the dimensions of the region of the homogeneous B 0- magnetic field can restrict the field of application of the medical imaging system.The design measures therefore preferably comprise one of the following measures:a limitation of the dimensions,restricting a homogeneous magnetic field range.In the case of the restriction of the dimensions, "abuse" is made more difficult from the outset by virtue of the fact that body parts for which the medical imaging system is not provided do not fit into the patient opening.When restricting the homogeneous magnetic field range, the examination region is restricted, so that extended body regions cannot be completely imaged with sufficient quality. These measures, which are already conventionally used, can be combined with the method according to the invention in order to ensure a dedicated use of a medical imaging system. In this way, "misbruches" can be reduced from the outset, so that in the case of the restricted dimensions of the patient opening unusable imaging is prevented from the outset in many cases, as a result of which increased efficiency of use of the medical imaging system is achieved. In the case of restricting a homogeneous magnetic field range, misuse may be notified based on the analysis of the image data, but image data of deteriorated quality may not be generated separately because the image data is already restricted in quality due to the non-uniformity of the magnetic field, so that separate generation of image data of deteriorated quality may be omitted. Both measures form a certain synergy in this case. Since additional filtering of the image data to render the image data unusable is no longer absolutely necessary.The invention is explained in more detail below with reference to the attached figures on the basis of exemplary embodiments. The following are shown: FIG. 1 is a flow chart illustrating a method for dedicated medical imaging according to an embodiment of the invention, FIG. 2 is a flow chart illustrating a method for dedicated medical imaging according to a second embodiment of the invention, FIG. 3 is a flow chart illustrating a method for dedicated medical imaging according to a third embodiment of the invention, FIG. 4 shows a schematic illustration of a monitoring device according to an exemplary embodiment of the invention, FIG. 5 shows a schematic illustration of a magnetic resonance imaging system according to an exemplary embodiment of the invention.Referring now to FIG. 1, there is shown a flow diagram 100 illustrating a method for dedicated medical imaging in accordance with an embodiment of the invention.In step 1.I, medical image data BD from a patient P is acquired with a medical imaging system which is intended for a specific type of imaging, for example for dental imaging.In step 1.II, a comparison of the acquired medical image data BD with previously known reference image data RBD is carried out in an automated manner. In the exemplary embodiment mentioned, the reference image data RBD comprise jaw images which are automatically compared with the currently acquired medical image data BD during the comparison. In the comparison, a content I of the acquired medical image data BD is determined.In step 1.III, an automated decision of a clearance decision relating to the medical image data BD is made on the basis of a result of the comparison. That is, the newly acquired medical image data BD is released only when they have been identified as dental photographs. In the event that the content I of the medical image data BD does not fall under the enabled use of the medical imaging system, which is marked with "n" in FIG. 1, the method moves on to step 1.IV, in which it is determined on the basis of the comparison result that no output NO of the medical image data BD takes place. Finally, in step 1.V, a message AL is output that the imaging has been carried out incorrectly and no medical image data BD are displayed to the user U.In the event that the content I of the medical image data BD falls under the enabled use of the medical imaging system, which is marked as "y" in FIG. 1, the method moves to step 1.VI, in which the enabled medical image data BD are transmitted to the user U.FIG. 2 shows a flow diagram 200 which illustrates a method for dedicated medical imaging according to a second exemplary embodiment of the invention.In step 2.I, medical image data BD from a patient P is acquired with a medical imaging system which is intended for a specific type of imaging, for example for one or more released body regions FKR.In step 2.II, the acquired medical image data BD are subjected to automated pattern recognition and image contents I of the image data BD are recognized. In particular, in step 2.II, it is determined which body region KR or which organ is imaged by the medical image data BD.In step 2.III, it is determined whether the identified body region KR falls below a body region FKR to be released. In the event that the body region KR does not fall below one of the body regions FKR to be released, which is marked with "n" in FIG. 2, the method moves on to step 2.IV. In step 2.IV, it is determined based on the comparison result that no image data NO is output. In step 2.V, a message AL is subsequently output that the magnetic resonance imaging system has been used incorrectly.In the event that the body region KR falls below one of the body regions FKR to be released, which is marked as "y" in FIG. 2, the method moves from step 2.III to step 2.VI, wherein the captured image data BD is output to the user U.FIG. 3 shows a flow chart 300 which illustrates a method for dedicated medical imaging according to a third exemplary embodiment of the invention.Analogously to the first and second exemplary embodiments, medical image data BD from a patient P is acquired in step 3.I.In step 3.II, an AI-based image recognition is carried out on the basis of the acquired medical image data BD, and contents I of the acquired medical image data BD, in particular body regions KR contained in the medical image data BD, are determined.In step 3.III, it is determined whether the body region KR falls below a body region FKR to be released. In the event that the body region KR does not fall below one of the body regions FKR to be released, which is marked with "n" in FIG. 3, the method moves from step 3.III to step 3.IV. In step 3.IV, image data BDR are output with reduced resolution, so that although the user recognizes which body region KR has been detected pictorially, the medical image data BD can continue to be used only to a limited extent.In the event that the body region KR falls below one of the body regions FKR to be released, which is marked as "y" in FIG. 3, the method moves from step 3.III to step 3.V, wherein the captured image data BD are output to the user U with full resolution.FIG. 4 shows a schematic illustration of a monitoring device 40 according to an exemplary embodiment of the invention. The monitoring device 40 has an input interface 41 for acquiring medical image data BD from a patient P from a magnetic resonance imaging system 10.Part of the monitoring device 40 according to the invention is also an image recognition unit 42 which is configured to identify contents of the acquired medical image data BD and in particular to recognize and segment body regions KR. The image recognition unit 42 is also connected to a database DB storing enabled body regions FKR whose information is matched with the recognized contents.The monitoring device 40 according to the invention also has an enabling unit 43 for automatically making an enabling decision FE relating to the medical image data BD on the basis of the comparison VE of the contents I detected by the image detection unit 42 with the data FKR of the database DB. The enabling decision FE is output from the enabling unit 43 to, for example, a communication interface with a user such as a display unit.FIG. 5 illustrates a schematic representation of a magnetic resonance imaging system 10 according to an exemplary embodiment of the invention.The magnetic resonance imaging system 10 has a scanning unit 11 and a control device 12. The control device 12 comprises a control unit 38 which is configured to control imaging of the scanning unit 11. The scanning unit 11 is controlled via control commands SB.Part of the control device 12 is also a reconstruction unit 39, which is configured to reconstruct image data BD on the basis of raw data RD that the reconstruction unit 39 receives from the scanning unit 11.The image data BD are transmitted to a monitoring device 40, which is likewise part of the control device 12. If the image data BD are released from the monitoring device 40, they are output to the user via a display unit 45, in particular a screen. If the image data BD are not released, image data with reduced resolution RMBD are alternatively output and / or a message AL is communicated that the image data BD are not output because of a misuse.Finally, it is pointed out once again that the methods and apparatuses described above are merely preferred exemplary embodiments of the invention and that the invention can be varied by the person skilled in the art without departing from the scope of the invention, insofar as it is specified by the claims. For the sake of completeness, it is also pointed out that the use of the indefinite articles "a" or "an" does not exclude that the features in question can also be present multiple times. Likewise, the term "unit" does not exclude it being composed of a plurality of components which may optionally also be spatially distributed. Regardless of the grammatical sex of a certain term, individuals with male, female or other sex identity are included.

Claims

Method for dedicated medical imaging, comprising the steps of: - acquiring medical measurement data (RD, BD) from an examination region (UB) of a patient (P), - automatically carrying out an image recognition on the basis of the acquired medical measurement data (RD, BD), - automatically making an enabling decision relating to medical image data (BD) generated on the basis of the medical measurement data (RD, BD), on the basis of the image recognition.Method according to claim 1, wherein the medical measurement data (RD, BD) comprise data with one of the following data types: - raw data (RD), - image data (BD), - pre-recording data.Method according to claim 1 or 2, wherein the image recognition comprises one of the following image data recognition methods: - a comparison (V) of the medical measurement data (RD, BD) with previously known reference measurement data (RMD), - an automated pattern recognition based on the acquired medical measurement data (RD, BD), - an image data recognition based on a model based on artificial intelligence, which is applied to the medical measurement data (RD, BD).Method according to one of the preceding claims, wherein, within the framework of the image recognition, an organ located in the examination region (UB) or a body region comprising the examination region (UB) is recognized.Method according to one of the preceding claims, wherein the image recognition comprises a classification of the acquired medical measurement data (RD, BD) and / or the generated medical image data (BD), and wherein the clearance decision is made as a function of the classification of the acquired medical measurement data and / or the generated medical image data (BD).Method according to claim 5, wherein the classification comprises an assignment of the medical image data (BD) to a specific type of examination region (UB), and wherein the enabling decision is made depending on the assigned type of examination region and only medical image data (BD) are enabled from one or more types of examination regions (UB).Method according to one of the preceding claims, wherein the clearance decision is made on the basis of specification data of a database (DB) which stores specification data for examination regions permitted for clearance.Method according to one of the preceding claims, wherein the enabling decision comprises enabling the medical image data (BD) with restricted image quality depending on a result of the image recognition carried out.Method according to claim 8, wherein the release with restricted image quality comprises: - releasing the medical image data (RMBD) with reduced resolution and / or - releasing the medical image data (RMBD) with reduced matrix size.Method according to one of the preceding claims, wherein restricted enabling of only a predetermined number of image recordings takes place on the basis of the image recognition.Method according to one of the preceding claims, wherein, in the event that no release is issued, one of the following additional measures takes place: - the medical imaging is discontinued, - an error message is issued, - the medical imaging system (10) used for dedicated medical imaging is deactivated for a predetermined period of time, - the patient (P) is removed automatically from the medical imaging system (10).Monitoring device (40), comprising: - an input interface (41) for receiving medical measurement data (RD, BD) from an examination region (UB) of a patient (P) from a medical imaging system (10), - an image recognition unit (42) for automatically carrying out an image recognition on the basis of the acquired medical measurement data (RD, BD), - an enabling unit (43) for automatically making an enabling decision, which relates to medical image data (BD) generated on the basis of the medical measurement data (RD, BD), on the basis of the image recognition.Medical imaging system (10), comprising: - a scanning unit (11) for generating medical image data (BD) from a patient (P), - a monitoring device (40) according to claim 12.A computer program product comprising instructions which, when a program is executed by a computer, cause the computer to carry out the steps of the method of any one of claims 1 to 11.A computer readable medium comprising instructions which, when executed by a computer, cause the computer to carry out the steps of the method of any one of claims 1 to 11.

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