Magnetic resonance imaging in radiotherapy planning

Abstract

A control unit (8) operates a magnetic resonance scanner (1) during the acquisition of magnetic resonance signals (S) during the examination of a patient (2) according to a number of protocols (P) and acquires the associated magnetic resonance signals (S). The control unit (8) first receives information (I) about the patient (2) from an oncology information system (11) and, depending on the information (I) retrieved from the oncology information system (11), automatically determines a number of protocols (P) with which the magnetic resonance scanner (1) is to be operated during the examination of the patient (2).

Description

[0001] The present invention is based on an operating method for a magnetic resonance scanner, wherein a control device of the magnetic resonance scanner operates the magnetic resonance scanner in the acquisition of magnetic resonance signals during the examination of a patient according to a number of protocols and acquires the associated magnetic resonance signals.

[0002] The applicant points out at this point that, regardless of the grammatical gender of a particular personal term (here, for example, the term “patient”), it should always include persons with male, female and other gender identities.

[0003] The term "protocol" has a clearly defined meaning in connection with the operation of a magnetic resonance scanner. It refers to the totality of temporally constant and temporally variable operating parameters with which the magnetic resonance scanner performs a specific signal acquisition. In particular, such a protocol specifies: - which radiofrequency coils (whole body coil, head coil, knee coil, pelvic coil, etc.) are used for exciting and receiving magnetic resonance signals and - with which temporal sequence and with which control curves and, if applicable, further parameters the various radio-frequency coils and gradient coils of the magnetic resonance scanner are controlled during the excitation of the magnetic resonance signals in the examination object and during the reception of magnetic resonance signals from the examination object.

[0004] The control sequences also include the temporal coordination of the control of the aforementioned coils. Furthermore, the protocols may also include the possible injection of a contrast agent. This applies not only to the prior art, but also within the scope of the present invention.

[0005] Typically, not just a single protocol is executed during the examination of a single patient, but a multitude of protocols. The number of protocols is therefore usually greater than 1. The use of multiple protocols can, for example, lead to the acquisition of images with different contrast or the reproduction of different physiological parameters. This also applies both to the prior art and to the scope of the present invention.

[0006] The present invention further relates to a computer program comprising machine code which can be directly processed by a control device of a magnetic resonance scanner and whose processing by the control device causes the control device to carry out such an operating method.

[0007] The present invention further relates to a control device of a magnetic resonance scanner, wherein the control device is designed as a software-programmable device and is programmed with such a computer program so that it carries out such an operating method.

[0008] The present invention further relates to a magnetic resonance scanner, wherein the magnetic resonance scanner has such a control device.

[0009] The items mentioned are generally known.

[0010] A magnetic resonance scanner is—both in the prior art and within the scope of the present invention—a medical imaging system in which the raw signals underlying the generated images are acquired in the form of magnetic resonance signals previously generated in a patient by appropriate excitation. Such systems—often referred to as magnetic resonance systems—are used in hospitals and larger medical practices for examining patients. Their design and operation are generally known to experts.

[0011] A wide variety of procedures are used to treat diseases. Radiotherapy is often used to treat some diseases, particularly tumors. Correct planning of this type of radiotherapy requires prior acquisition of images of the patient. This is a different type of signal acquisition than the imaging examination used in diagnosis. This is because, in order to make a diagnosis, precise, millimeter-accurate localization of the patient is often of secondary importance. When planning radiotherapy, however, it is necessary to determine exactly where certain organs, tumors, etc. of the patient are located so that the correct area is irradiated during radiotherapy. For this purpose, the patient is positioned on a patient table as precisely as possible in the same way as the patient will be positioned during later radiotherapy. Signal acquisition then takes place.Based on this signal acquisition, the radiotherapy is then planned.

[0012] Current technology typically uses computed tomography (CT) scanners for signal acquisition, which forms the basis for radiation therapy planning. CT scanners provide a high-quality three-dimensional image of the patient's anatomy. Signal acquisition is relatively rapid, and the associated workflows are well-established.

[0013] In radiology—this also applies to radiation therapy planning—it is common practice for an information system to exchange basic data regarding a patient examination schedule using a medical imaging modality (usually a CT scanner). This specifies when each patient should be examined.

[0014] Recently, there has been increased interest in using magnetic resonance imaging (MRI) in addition to or as an alternative to CT scanning for signal acquisition, which informs radiotherapy planning. MRI scanning offers the advantages of high tissue contrast and the ability to provide both morphological and functional images with varying contrast. Another advantage is that the patient does not need to be exposed to a dose of ionizing radiation for signal acquisition.

[0015] Magnetic resonance scanners, however, also have significant disadvantages.

[0016] Signal acquisition is often considerably more complex. In particular, there are a large number of different sequences and protocols with numerous adjustable acquisition parameters, which, depending on the selection and settings, can significantly influence the quality of the generated images.

[0017] Furthermore, with magnetic resonance scanners it is often necessary to apply a large number of local coils to the patient in order to generate high-quality images. In many cases the local coils are applied directly to the patient, for example so that they rest on the patient or the patient rests on the corresponding local coil. This often results in deformations of the patient. For the pure diagnostic purpose these deformations can usually be accepted without further ado. However, during radiation therapy planning such deformations are not tolerable. As already mentioned during radiation therapy planning the patient must be positioned as precisely as possible in the same way as the patient will be positioned during the subsequent radiation therapy.To resolve this conflict, a considerable number of procedures are required so that, on the one hand, the local coils can be applied, but, on the other hand, no deformation of the patient is caused.

[0018] Therefore, properly conducting a patient imaging examination for radiation therapy planning requires highly qualified personnel. Both signal acquisition and the preparation of the magnetic resonance scanner are cumbersome and time-consuming.

[0019] In principle, it is conceivable to train staff accordingly. However, such training is also complex. Furthermore, the pool from which staff can be recruited is often very small. This is because there are only a few people who are sufficiently familiar with both the issues surrounding magnetic resonance imaging and the problems associated with signal acquisition for planning radiation therapy.

[0020] In order to enable the integration of a magnetic resonance scanner into signal acquisition for radiotherapy planning, the workflows involved in operating the magnetic resonance scanner must be simplified and automated.

[0021] The object of the present invention is to create possibilities by means of which the integration of a magnetic resonance scanner into the imaging for planning radiotherapy is significantly simplified.

[0022] The object is achieved by an operating method for a magnetic resonance scanner having the features of claim 1. Advantageous embodiments of the operating method are the subject of dependent claims 2 to 4.

[0023] According to the invention, an operating method of the type mentioned at the outset is designed in that the control device receives information from the patient from an oncology information system and, depending on the information from the patient received from the oncology information system, automatically determines a number of protocols with which the magnetic resonance scanner is to be operated during the examination of the patient.

[0024] In the control unit, for example, the corresponding protocols can be assigned to a large number of typical examinations. In such a case, all that is required is to read the examination from the received information and then select the corresponding protocols.

[0025] An oncology information system is a computer system often installed in hospitals that serves to document patient findings during cancer examinations and plan the associated therapies. It provides standardized terminology and procedures. This is especially true for the communication structures of the oncology information system, which the oncology information system shares with other units.

[0026] The patient information may be information about the intended treatment for a specific patient for radiotherapy. Such radiotherapy also indirectly determines an intended examination of the patient, which is carried out before the actual radiotherapy as part of the radiotherapy planning. Alternatively or additionally, the patient information may be the examination of the patient required before the actual radiotherapy. Again alternatively or additionally, it may also be other patient data. Examples of such other data include information about the patient's kidney function. Such information may be relevant, for example, if contrast examinations are to be carried out as part of the radiotherapy planning.The other data may also include previously acquired diagnostic or simulation images, including their setup and acquisition parameters.

[0027] In the latter case, when the patient information also includes the setup and acquisition parameters of previous recordings, in some cases these parameters can be directly adopted as protocols or the protocols can be derived from them.

[0028] For the sake of clarity, it should be noted that the phrase "specifies a number of protocols" does not refer to the number itself, i.e., that the control device determines whether 3, 4, or 5, etc., protocols should be used. Rather, the phrase means that the control device determines which protocols are selected and used.

[0029] The inventive approach goes far beyond the familiar specification of a schedule. Rather, it also specifies the very specific operation of the magnetic resonance scanner, such as the slice resolution, the scan protocol, the FoV (field of view), the administration of contrast agents, etc.

[0030] Preferably, the control device outputs the protocols it has determined to an operator of the magnetic resonance scanner before operating the magnetic resonance scanner and receives a confirmation command from the operator, with or without prior modification of the protocols. This enables the operator, on the one hand, to finalize the protocols, usually by simply confirming them. On the other hand, it enables the operator to modify and adapt the protocols as needed.

[0031] Depending on the patient and the type of examination, processing of the images generated from the acquired magnetic resonance signals may be necessary or useful. In this case, the control unit processes the generated images according to a processing algorithm.

[0032] Examples of such image processing, commonly referred to as "post-processing," include a so-called synthetic CT and automated segmentation. Based on the patient information received from the oncology information system, the control unit can, in particular, automatically determine whether and, if so, which image processing is desired and, if necessary, perform the image processing automatically.

[0033] The associated processing algorithms are often configured with processing parameters. The control unit therefore configures the processing algorithm with the processing parameters before processing the generated images. In this case, the control unit preferably determines the processing parameters automatically based on the patient information received from the oncology information system. This also simplifies image processing accordingly.

[0034] The object is further achieved by a computer program having the features of claim 5. According to the invention, the processing of the machine code by the control device causes the control device to execute an operating method according to the invention.

[0035] The object is further achieved by a control device having the features of claim 6. According to the invention, the control device is programmed with a computer program according to the invention, so that the control device executes an operating method according to the invention.

[0036] The object is further achieved by a magnetic resonance scanner having the features of claim 7. According to the invention, the control device is designed as a control device according to the invention.

[0037] The above-described properties, features, and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more readily understood in connection with the following description of the embodiments, which are explained in more detail in conjunction with the drawings. Herein, in schematic representation: Fig. 1 a magnetic resonance scanner, Fig. 2 a flow chart, Fig. 3 a flow chart, Fig. 4 a plan view of a scanner room, Fig. 5 a patient table from above and Fig. 6 a patient table from the side.

[0038] According to Fig. 1, magnetic resonance signals S of a patient 2 are to be acquired using a magnetic resonance scanner 1. Based on the acquired magnetic resonance signals S, images B of the patient 2 are generated. The generated images B of the patient 2 and / or images B' generated by processing the images B are to be used later in the context of radiation therapy planning.

[0039] The magnetic resonance scanner 1 is constructed in a conventional manner. It comprises a base magnet 3. Using the base magnet 3, which is often superconducting, a temporally static and spatially homogeneous basic magnetic field is generated in an examination volume 4. The basic magnetic field has a significant strength, for example, a strength of 1.5 T or 3 T. The magnetic resonance scanner 1 further comprises a gradient system 5. Using the gradient system 5, gradient fields can be superimposed on the basic magnetic field. The magnetic resonance scanner 1 further comprises a whole-body coil 6. Using the whole-body coil 6, an RF field can be generated in the examination volume 4. The frequency of the RF field, the so-called Larmor frequency, is determined by the gyromagnetic ratio of the magnetic resonance signals S to be excited and the strength of the basic magnetic field. The whole-body coil 6 is often designed as a birdcage.In the typical case of detecting the magnetic resonance of hydrogen atoms, the gyromagnetic ratio is approximately 42.6 MHz / T. The reception of excited magnetic resonance signals S can also be achieved with the whole-body coil 6. However, reception is often achieved using local coils 7 due to the significantly better signal-to-noise ratio. Fig. For the sake of clarity, only a single local coil 7 is shown in Figure 1. In reality, many local coils 7 are often present.

[0040] The magnetic resonance scanner 1 has a control device 8, which controls the magnetic resonance scanner 1. The control device 8 is, as shown in Fig. 1 is indicated by the designation "µP," is designed as a software-programmable device. The control device 8 is programmed with a computer program 9. The control program 9 comprises machine code 10, which can be directly processed by the control device 8. Due to the programming of the control device 8 with the computer program 9, the control device 8 processes the machine code 10 during operation. The processing of the machine code 10 causes the control device 8 to execute an operating method, which is explained in more detail below.

[0041] According to Fig. 2, the control device 8 receives in a step S1 from an oncology information system 11 (see Fig. 1), with which the control device 8 is connected for data purposes, receives information I from the patient 2. It is possible for the control device 8 to actively retrieve the information I from the oncology information system (pull principle). Alternatively, it is possible for the information I to be provided to the control device 8 by the oncology information system 11 (push principle).

[0042] The information I initially comprises the data for identifying the patient 2 as such, i.e., their name, date of birth, etc. Furthermore, the information I can comprise data on intended radiotherapy. In this case, it must be possible to derive from the data on the intended radiotherapy which examinations of the patient 2 are to be performed using the magnetic resonance scanner 1. Alternatively, the information I can directly comprise which examinations of the patient 2 are to be performed using the magnetic resonance scanner 1. In addition, the information I can also comprise older diagnoses. If necessary, the information I can also comprise setting data on medical imaging modalities with which the medical imaging modalities were set when acquiring the images on which the older diagnoses are based.If the medical imaging modalities included magnetic resonance imaging systems, the settings may also include the protocols used at that time.

[0043] In a step S2, the control device 8 automatically determines, depending on the information I, a number of protocols P with which the magnetic resonance scanner 1 is to be operated during the examination of the patient 2. For example, many possible protocols P are usually stored in the control device 8. The term "protocol" is clearly defined for those skilled in the art in the field of magnetic resonance systems. For example, it is possible to note for a large number of possible examinations which protocols P are to be used and in which order the protocols P are to be used. If, based on the information I from previous examinations with magnetic resonance systems, the protocols used at that time are known, these protocols can also be adopted directly if necessary. In both cases, the control device 8 can easily determine the specific protocols P to be used in step S2.

[0044] In a step S3, the control device 8 outputs the protocols P determined in step S2 via an interface 12 (see Fig. 1) to an operator 13 of the magnetic resonance scanner 1. The term "interface 12" refers here to the hardware device, for example, a monitor with the associated keyboard and other input devices such as a mouse.

[0045] The operator 13 can leave the protocols P unchanged. They can also modify them by entering modification commands. Therefore, the operator 13 issues a confirmation command C to the control device 8 either without modifying the protocols P or after modifying them. The control device 8 accepts the confirmation command C in a step S4.

[0046] Next, in a step S5, the control device 8 operates the magnetic resonance scanner 1 according to the protocols P, i.e., according to the protocols P determined by the control device 8 in step S2 and possibly modified by the operator 13 between steps S3 and S4. This results in the operation of the magnetic resonance scanner 1 and the acquisition of the associated magnetic resonance signals S during the examination of the patient 2.

[0047] Although steps S3 and S4 are typically present, they are not mandatory. If they are not required, the control device 8 always operates the magnetic resonance scanner 1 in step S5 according to the unchanged protocols P determined in step S2.

[0048] The acquisition of the magnetic resonance signals S is usually followed by the generation of the corresponding images B in a step S6. This generates the images B as such. This generation, i.e., the conversion of the magnetic resonance signals S initially acquired in k-space into spatial space, is always required.

[0049] In many cases, the images B are further processed after their generation. This generates a processed image B'. The processing itself, if carried out, is carried out according to Fig. 2 in a step S9. The processing is carried out according to a processing algorithm A. In many cases, the control device 8 parameterizes the processing algorithm A in a step S8 and thus before processing the generated images B with processing parameters PA. The determination of the processing parameters PA can be carried out as required. For example, the operator 13 can set the processing parameters PA. Preferably, however, the processing parameters PA are determined as shown in Fig. 2 the control device 8 automatically adjusts the processing parameters PA in a step S7, which is carried out before step S8, depending on the information I received from the oncology information system 11.

[0050] The present invention can be further developed. In particular, for the correct acquisition of the magnetic resonance signals S, it is often necessary to prepare the magnetic resonance scanner 1 and / or the patient 2 for the examination. The term "correct acquisition" is meant here in the sense that the radiation therapy planning based on the generated images B, B' can be carried out correctly, i.e., that the correct location of the patient 2 is irradiated during the radiation therapy. To prepare the magnetic resonance scanner 1 and / or the patient 2, the procedure is preferably as described below in connection with Fig. 3 is explained in more detail. The procedure according to Fig. 3 is realized by the control device 8 based on the programming with the computer program 9 or the processing of the machine code 10.

[0051] According to Fig. 3, steps S11 to S17 are present. The steps S11 to S17 are carried out according to Fig. 3 after step S1 (compare Fig. 2) and before step S2 (compare again Fig. 2) is carried out.

[0052] In step S11, the control device 8 automatically determines a configuration K of the magnetic resonance scanner 1. The configuration K of the magnetic resonance scanner 1 determined in step S11 is the configuration in which the magnetic resonance scanner 1 is to be operated during the examination of the patient 2. Likewise, in step S12, the control device 8 automatically determines a position L of the patient 2. The position L of the patient 2 determined in step S12 is the position in which the patient 2 is to be positioned during the examination of the patient 2. The control device 8 performs both the determination in step S11 and the determination in step S12 depending on the information I, i.e., depending on the information I about the patient 2 received from the oncology information system 11.

[0053] In step S13, the control device 8 determines the preparatory measure that should be carried out first on the magnetic resonance scanner 1 and / or on the patient 2. In step S14, the control device 8 outputs information I' about the respective preparatory measure to be carried out to the operator 13 via an operator interface 14. For example, an image of the patient 2 and / or a patient couch (hereinafter also referred to as a patient table) can be displayed on a screen or the like, in which the area in which the corresponding preparatory measure is to be carried out is visually highlighted. What is to be done can also be specified in text form and / or in images. An example: The text "Mount coil holder X at location Y of the patient couch and mount local coil Z on coil holder X" is output.At the same time, the corresponding area of ​​the patient bed can be visually highlighted, for example, by changing the color and / or flashing. Additionally, images or other markings of the coil holder X and the local coil Z can be displayed if necessary.

[0054] The operator 13 performs this preparatory measure and then confirms the execution of the preparatory measure via the operator interface 14. The control device 8 receives the confirmation in step S15. Upon receipt of the confirmation C' from the operator 13 regarding the execution of the respective preparatory measure, the control device 8 proceeds to step S16.

[0055] In step S16, the control device 8 checks whether all preparatory measures have already been performed. If not all preparatory measures have yet been performed, the control device 8 determines in step S17 the preparatory measure to be performed next on the magnetic resonance scanner 1 and / or on the patient 2. The control device 8 then returns to step S14. Otherwise, the control device 8 proceeds to step S2.

[0056] The approach of Fig. 3 thus causes the operator 13 to successively carry out the preparatory measures on the magnetic resonance scanner 1 and / or on the patient 2 before the examination of the patient 2 in the magnetic resonance scanner 1 and thereby bring about the desired configuration K of the magnetic resonance scanner 1 and the desired positioning L of the patient 2. Within the scope of the procedure of Fig. 3, the information I' on the preparatory measures to be carried out is output step by step according to their chronological sequence.

[0057] The term "operator interface 14" refers to the hardware device, analogous to interface 12, such as a monitor with the associated keyboard and other input devices such as a mouse. In individual cases, the operator interface 14 and interface 12 may be one and the same device. However, often, as shown in Fig. 4 are different facilities. In particular, as a rule, as shown in Fig. 4, the magnetic resonance scanner 1 is arranged in a scanner room 15. The scanner room 15 is completely surrounded by walls 16, with a door 17 arranged in at least one wall 16. The walls 16 and the door 17 are often transparent to a considerable extent. However, this is of secondary importance within the scope of the present invention.

[0058] The interface 12 is as shown in Fig. 4 is generally arranged outside the scanner room 15. In exceptional cases, however, it can also be arranged within the scanner room 15. The operator interface 14, however, is preferably arranged in the scanner room 15—at least during the execution of the preparation method. The arrangement in the scanner room 15 can be achieved by arranging the operator interface 14 in a fixed location in the scanner room 15. In this case, the operator interface 14 is permanently arranged in the scanner room 15. Alternatively, the operator interface 14 can be portable, i.e., connected to the control device 8 via a cable or, preferably, wirelessly, so that the operator 13 can vary the specific location at which the operator interface 14 is arranged in the scanner room 15 as needed.

[0059] The preparatory measures that the operator 13 performs can be determined as required. For example, the preparatory measures can be carried out according to Fig. 5 include the arrangement of positioning aids 18 for the patient 2 on a patient table 19 of the magnetic resonance scanner 1. The patient table 19 is intended for the reception of the patient 2, so that the patient 2 lies on the patient table 19. The exemplary in Fig. The positioning aids 18 shown in Figure 6 can be stops against which the patient 2 rests with the soles of his feet. However, the positioning aids 18 shown are purely exemplary. Alternatively or additionally, the preparatory measures can include the arrangement of immobilization aids 20 for the patient 2 on the patient table 19. Examples are shown in Figure 6. Fig. 5 immobilization aids 20 are shown, between which the head of the patient 2 is placed. Alternatively or additionally, the preparatory measures can be carried out according to Fig.6 may include arranging coil holders 21 on the patient table 19. Local coils 7 can be arranged indirectly on the patient table 19 using the coil holders 21. Alternatively or additionally, the local coils 7 can also be arranged directly on the patient table 19, provided the local coils 7 are prepared accordingly. Other preparatory measures are also possible.

[0060] In summary, the present invention relates to the following: A control device 8 operates a magnetic resonance scanner 1 during the acquisition of magnetic resonance signals S during the examination of a patient 2 according to a number of protocols P and acquires the associated magnetic resonance signals S. The control device 8 previously receives information I of the patient 2 from an oncology information system 11 and, depending on the information I of the patient 2 received from the oncology information system 11, automatically determines a number of protocols P with which the magnetic resonance scanner 1 is to be operated during the examination of the patient 2.

[0061] The present invention has many advantages. In particular, it allows even less intensively trained operators 13 to operate the magnetic resonance scanner 1 properly. The protocols P can be defined fully automatically or at least with just a few mouse clicks (or similar input operations). The same applies to the processing of the generated images B. The preparation of the magnetic resonance scanner 1 and / or the patient 2 before the examination is also significantly simplified. The operator 13 can devote more attention to the patient 2, since their attention does not have to be directed to the magnetic resonance scanner 1. Errors that would otherwise be caused by a lack of confidence on the part of the operator 13 can often be avoided.

[0062] Although the invention has been illustrated and described in detail by the preferred embodiment, the invention is not limited to the disclosed examples and other variations may be derived therefrom by those skilled in the art without departing from the scope of the invention.

Claims

[1] Operating method for a magnetic resonance scanner (1), wherein a control device (8) operates the magnetic resonance scanner (1) in the acquisition of magnetic resonance signals (S) during the examination of a patient (2) according to a number of protocols (P) and acquires the associated magnetic resonance signals (S), characterized by that the control device (8) receives information (I) of the patient (2) from an oncology information system (11) and, depending on the information (I) of the patient (2) received from the oncology information system (11), automatically determines a number of protocols (P) with which the magnetic resonance scanner (1) is to be operated during the examination of the patient (2). [2] Operating method according to claim 1, characterized bythat the control device (8) outputs the protocols (P) determined by it to an operator (13) of the magnetic resonance scanner (1) before operating the magnetic resonance scanner (1) and receives a confirmation command (C) from the operator (13) with or without prior modification of the protocols (P). [3] Operating method according to claim 1 or 2, characterized by that the control device (8) processes images (B) generated on the basis of the acquired magnetic resonance signals (S) according to a processing algorithm (A). [4] Operating method according to claim 3, characterized by that the control device (8) parameterizes the processing algorithm (A) with processing parameters (PA) before processing the generated images (B) and that the control device (8) determines the processing parameters (PA) automatically as a function of the information (I) of the patient (2) received by the oncology information system (11). [5] Computer program comprising machine code (10) which can be directly processed by a control device (8) of a magnetic resonance scanner (1) and whose processing by the control device (8) causes the control device (8) to carry out an operating method according to one of claims 1 to 4. [6] Control device of a magnetic resonance scanner (1), wherein the control device is designed as a software-programmable device and is programmed with a computer program (9) according to claim 5, so that it carries out an operating method according to one of claims 1 to 4. [7] Magnetic resonance scanner, wherein the magnetic resonance scanner comprises a control device (8) according to claim 6.

Images