A shimming control system and shimming method for a magnetic resonance imaging system

Abstract

The present application relates to the field of magnetic resonance imaging technology, and in particular to a shimming control system and shimming method for a magnetic resonance imaging system, wherein the shimming control system comprises: a remote module connected to the magnetic resonance imaging system, used to remotely control the host of the magnetic resonance imaging system to start the shimming scanning program and obtain the shimming file; a parsing module connected to the remote module, used to parse the shimming file, determine the result of the current shimming scan and the shimming parameters; a shimming power supply control module connected to the parsing module and the shimming power supply and the heater power supply, used to configure the shimming power supply and the heater power supply for shimming according to the shimming parameters; a shimming switching module connected to the shimming power supply control module and the shimming power supply, used to switch the coil connected to the shimming power supply. The shimming method for the magnetic resonance imaging system of the present application avoids the problem that manual shimming operation is inefficient and prone to errors.

Description

Technical Field

[0001] The present application relates to the technical field of magnetic resonance imaging, and particularly to a shimming control system and a shimming method for a magnetic resonance imaging system. Background Art

[0002] The most important component in a magnetic resonance imaging system is the magnet, whose function is to provide a stable magnetic field environment. To ensure the stability of the magnetic field environment, it is necessary to adjust the coil current inside the magnet of the magnetic resonance imaging system, and the adjustment process is called shimming.

[0003] In the prior art, the process of performing shimming usually involves starting the shimming scan program of the magnetic resonance imaging system to generate a text data file with the suffix lvshim, which is also called the shimming file. This file will detail whether the various indicators of the current working space of the magnet of the magnetic resonance imaging system have reached the standard, the current current value of the magnet coil, and the correction current value required for the magnet uniformity to reach the standard. Then, the engineer copies this file to the PC side and uses a text reading tool to view the text data file, and then records the current current value and the correction current value of the magnet coil by taking pictures or copying, etc. Then, the output of the shimming power supply is manually adjusted according to the current current value and the correction current value of the magnet coil to complete shimming.

[0004] However, since there are often a large number of coils in a magnetic resonance imaging system, there will also be corresponding current values and correction current values of the magnet coils in the text data file after shimming scan, resulting in the engineer having to continuously manually record the current current value and the correction current value, and correspondingly manually configure the shimming power supply, which is inefficient and error-prone. Summary of the Invention

[0005] To solve the deficiencies of the prior art, the purpose of the present application is to provide a shimming control system, method, electronic device and storage medium for a magnetic resonance imaging system, so as to improve the efficiency and accuracy of shimming.

[0006] To achieve the above purpose, the present application provides a shimming control system for a magnetic resonance imaging system, including:

[0007] A remote module, connected to the magnetic resonance imaging system, for remotely controlling the host of the magnetic resonance imaging system to start the shimming scan program and obtain the shimming file;

[0008] An analysis module, connected to the remote module, for analyzing the shimming file to determine the result of the current shimming scan and the shimming parameters;

[0009] The shimming power supply control module is connected to the parsing module, the shimming power supply, and the heater power supply, and is configured to configure the shimming power supply and the heater power supply according to the shimming parameters for shimming. The shimming power supply and the heater power supply are respectively used to supply power to the coil and the heater;

[0010] The shimming switching module is connected to the shimming power supply control module and the shimming power supply, and is configured to switch the coil connected to the shimming power supply.

[0011] Further, the shimming parameters at least include: magnet type, magnet center frequency, coil current value, and coil current correction value.

[0012] Further, the specific steps of configuring the shimming power supply and the heater power supply according to the shimming parameters for shimming further include:

[0013] Based on the magnet type, configure the output current of the heater power supply;

[0014] Configure the shimming power supply to output a first current equal to the coil current value;

[0015] Turn on the heater, and after a first predetermined time, connect the shimming power supply to the coil;

[0016] Configure the shimming power supply to output a second current equal to the coil current correction value;

[0017] After a second predetermined time, turn off the heater and the shimming power supply.

[0018] Further, the shimming power supply control module is further configured to: calculate the magnet center frequency after modifying the coil current, and determine whether the change value of the magnet center frequency exceeds a predetermined center frequency scanning range; if it exceeds, remotely control the center frequency of the shimming scan to be the calculated magnet center frequency, and then start the shimming scan.

[0019] Further, the remote module controls the magnetic resonance imaging system through the VNC remote desktop and remotely obtains the shimming file generated after the shimming scan ends through SSH.

[0020] To achieve the above object, the present application provides a shimming method for a magnetic resonance imaging system, which is applied to the shimming control system of the magnetic resonance imaging system as described above, and includes:

[0021] Step S101: In response to the shimming of the magnetic resonance imaging system, the remote module controls the magnetic resonance imaging system to start the shimming scan and obtain the shimming file generated after the shimming scan ends;

[0022] Step S102: The parsing module parses the shimming file, determines the shimming scan result of the shimming file. If it passes, the shimming ends; if it does not pass, the shimming parameters of the magnetic resonance imaging system for the current shimming scan are extracted.

[0023] Step S103: Based on the shimming parameters, the shimming power supply control module configures the shimming power supply, the heater power supply, and the shimming switching module modifies the coil current.

[0024] Step S104: Repeat the above steps S101 - S103 until the shimming ends.

[0025] To achieve the above object, the electronic device provided by the present application includes:

[0026] A processor;

[0027] A memory, on which one or more computer program instructions running on the processor are stored;

[0028] Wherein, when the processor runs the computer instructions, it executes the shimming method of the magnetic resonance imaging system as described above.

[0029] To achieve the above object, the computer - readable storage medium provided by the present application stores computer instructions, and when the computer instructions are run by a processor, the steps of the shimming method of the magnetic resonance imaging system as described above are executed.

[0030] The shimming control system of the magnetic resonance imaging system provided by the present application starts the shimming scan remotely, automatically obtains and parses the shimming file, and then automatically configures the shimming power supply and the heater power supply according to the shimming parameters, adjusts the coil current until the magnetic field is stable, avoiding the problems of low efficiency and easy error in manual operation.

[0031] Other features and advantages of the present application will be described in the subsequent specification, and, in part, will be obvious from the specification, or will be understood by implementing the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The drawings are used to provide a further understanding of the present application, and constitute a part of the specification, and together with the embodiments of the present application, are used to explain the present application, and do not constitute a limitation to the present application. In the drawings:

[0033] Figure 1 is a schematic structural diagram of the shimming control system of the magnetic resonance imaging system of the present application;

[0034] Figures 2 - 3 is a schematic content diagram of the shimming file;

[0035] Figure 4 is a schematic flow diagram of the shimming method of the magnetic resonance imaging system of the present application. Detailed implementation manners

[0036] Embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although some embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. On the contrary, these embodiments are provided to more thoroughly and completely understand the present application. It should be understood that the drawings and embodiments of the present application are only for exemplary purposes and are not used to limit the protection scope of the present application.

[0037] It should be understood that the steps recited in the method embodiments of the present application can be executed in different orders and / or executed in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present application is not limited in this regard.

[0038] The term "including" and its variations used herein are open-ended, that is, "including but not limited to". The term "based on" is "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". The relevant definitions of other terms will be given in the following description.

[0039] It should be noted that the modifications of "one" and "multiple" mentioned in the present application are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly specified in the context, it should be understood as "one or more". "Multiple" should be understood as two or more.

[0040] The most important part of a magnetic resonance imaging system is the magnet, whose function is to provide a stable magnetic field environment. To ensure the stability of the magnetic field environment, it is necessary to adjust the coil current inside the magnet of the magnetic resonance imaging system, and the adjustment process is called shimming.

[0041] Several groups of superconducting magnetic field coils are arranged inside the magnet of the magnetic resonance imaging system. By adjusting the current of each superconducting magnetic field coil, the magnetic field in the working space in the middle of the magnet can be made uniform.

[0042] After the magnetic resonance imaging system starts shimming, it will start its own shimming scan program to generate a text data file with the suffix lvshim. This file is also called the shim file, which will detail whether the current working space of the magnet of the magnetic resonance imaging system meets the standards, the current current value of the magnet coil, and the corrected current value required for the magnet uniformity to meet the standards.

[0043] The heater, commonly known as Heater in the industry, functions to make a small section of the superconducting magnetic field coil inside the magnet lose its superconducting property, so that the remaining superconducting coils can be connected to the output of the shimming power supply, changing the current in the superconducting magnetic field coil. When the Heater is turned off, the superconducting coil will return to its superconducting property, forming a complete closed loop. At this time, changes in the shimming power supply will not affect the current value of the internal coil, that is, the Heater is equivalent to a switch set between the shimming power supply and the superconducting magnetic field coil, controlling when the internal coil of the magnet and the shimming power supply are connected.

[0044] Next, embodiments of the present application will be described in detail with reference to the accompanying drawings.

[0045] Embodiment 1

[0046] An embodiment of the present application provides a shimming control system for a magnetic resonance imaging system, which improves the efficiency and accuracy of shimming.

[0047] Figure 1 For the structural schematic diagram of the shimming control system of the magnetic resonance imaging system of the present application, the following will refer to Figure 1 The shimming control system of the magnetic resonance imaging system of the present application will be described in detail, including:

[0048] The remote module 200 is connected to the magnetic resonance imaging system 100 and is used to remotely control the host of the magnetic resonance imaging system 100 to start the shimming scan program and obtain the shimming file;

[0049] In this embodiment, the remote module 200 remotely controls the host of the magnetic resonance imaging system to start the shimming scan program on the host through VNC remote desktop, and remotely obtains the shimming file generated after the shimming scan through SSH; SSH is a network security protocol that realizes secure access and file transfer and other services through encryption and authentication mechanisms.

[0050] In some other embodiments, other data transmission methods can also be used to obtain the shimming file.

[0051] It should be noted that a shimming scan will last about 2 - 3 minutes. After the shimming scan is completed, a text data file with the suffix lvshim will be generated, and this file is also called the shimming file. Refer to Figures 2 - 3 .

[0052] The parsing module 300 is connected to the remote module 200 and is used to parse the shimming file to determine the result of the current shimming scan and the shimming parameters;

[0053] In this embodiment, by reading the shimming file and using data mining and data processing methods such as regular expressions, the parsing obtains Figure 2The magnet type magnetType in the shimming file, Figure 3 The magnet center frequency xmtfreq, the existing coil current value Existing, and the coil current correction value New in the shimming file.

[0054] It should be noted that, Figure 3 the coil in corresponds to the coil. In the magnetic resonance imaging system of this embodiment, there are three groups of coils, namely AX, T1, and T2. Each group of coils has 6 coils, for a total of 18 coils. The coils in the same group are controlled by the same heater.

[0055] Such as Figure 3 shown, there will be the results of the shimming scan in the shimming file, that is, "LV shim failed" in the figure. There are only two results of the shimming scan. The other is "LV shim passed". When it is parsed that the shimming scan result is "LV shim passed", it means passing, indicating that the shimming is successful and the shimming ends; when it is parsed that the shimming scan result is "LV shim failed", it means not passing. At this time, the parsed magnet type magnetType, magnet center frequency xmtfreq, and the existing current values Existing of each coil and the coil current correction value New are extracted.

[0056] The shimming power supply control module 400 is connected to the parsing module 300, the shimming power supply 600, and the heater power supply 700, and is used to configure the shimming power supply 600 and the heater power supply 700 according to the shimming parameters for shimming.

[0057] The shimming switching module 500 is connected to the shimming power supply control module 400 and the shimming power supply 600, and is used to switch the coils connected to the shimming power supply 600. While reducing the number of shimming power supplies used and lowering the cost, it improves the efficiency of modifying the coil current.

[0058] In this embodiment, there are a total of 18 coils in the magnetic resonance imaging system 100, which are divided into three groups: AX, T1, and T2. Each group of coils has 6 coils. Each group of coils corresponds to a heater heater. During the process of configuring the shimming power supply and the heater power supply to modify the coil current, the coil current is modified in groups, that is, 6 shimming power supplies are used at a time to modify the 6 coils corresponding to the same heater heater respectively. After modifying three times, the modification of the currents of all 18 coils is completed. Each time it is completed, the shimming switching module switches the coils connected to the shimming power supply to re-modify the current of the connected coils.

[0059] In this embodiment, the shimming power supply control module 400 controls the shimming power supply 600, the heater power supply 700, and the shimming switching module 500 through the serial port.

[0060] Specifically, the shimming power supply control module 400 configures the output current of the heater power supply 700 according to the magnet type, so that the heater works at the corresponding current; then configures the shimming power supply 600 to output a first current equal to the current value of the coil at present, that is, according to the extracted current value of the coil at present, configures the shimming power supply 600 to output a first current equal to the current value of the coil at present at a certain rate, the purpose of which is to ensure that there is no potential difference when the shimming power supply is connected to the coil; then, turns on the heater, and after a first predetermined time, connects the shimming power supply 600 to the coil; controls the heater between the coil to be adjusted and the shimming power supply to be turned on, so that the shimming power supply 600 is connected to the coil; then, configures the shimming power supply 600 to output a second current equal to the coil current correction value, specifically, according to the extracted current value of the coil at present, configures the shimming power supply 600 to output a second current equal to the coil current correction value at a certain rate, so that the current of the coil is the magnitude of the coil current correction value; finally, after a second predetermined time, turns off the heater power supply 700 and the shimming power supply 600.

[0061] It should be noted that the rate when outputting the second current is less than the rate when outputting the second current.

[0062] Exemplarily, for example, the rate when outputting the first current is 1 A / s, and the rate when outputting the second current is 0.2 A / s.

[0063] Specifically, after the shimming power supply 600 starts to output the second current, after the time specified by the manufacturer of the set magnetic resonance imaging system, turns off the heater, and then waits for 180 s to 300 s. After the coil is disconnected from the shimming power supply 600, then turns off the shimming power supply 600.

[0064] In this embodiment, the shimming switching module 500 is a multi-channel switch. The input end of the switch is connected to the shimming power supply 600, the output end is connected to all coils, and the control end is connected to the shimming power supply control module 400 to modify the current of the coils in groups.

[0065] In this embodiment, 6 shimming power supplies 600 are used to modify 6 coils corresponding to the same heater respectively once, and this is done three times to complete the modification of the currents of all 18 coils. Each time it is completed, the shimming power supply 600 switches the coils connected to the shimming power supply 600, and re-modifies the currents of the connected coils.

[0066] After adjusting the currents of all coils, remotely control to start the shimming scan again, obtain and analyze the generated shimming file again, judge whether the shimming scan result passes. If it does not pass, continue to adjust the coil current according to the newly analyzed shimming parameters until it is parsed that the shimming scan result passes, indicating that the shimming is completed.

[0067] Specifically, after adjusting all coil currents, the remote module remotely controls to start the shimming scan again, obtains and analyzes the generated shimming file again, and determines whether the shimming scan result passes. If it does not pass, the coil currents are continuously adjusted according to the newly analyzed shimming parameters until it is parsed that the shimming scan result passes, indicating the end of shimming.

[0068] In this embodiment, after adjusting the coil currents and before starting the shimming scan again, the shimming power supply control module also calculates the magnet center frequency after modifying the coil currents, and the calculation formula is as follows:

[0069] ;

[0070] where is the magnet center frequency after modifying the coil currents, is the original magnet center frequency, and ΔAX_2, ΔAX_4, ΔAX_6 are the current value differences corresponding to the 2nd, 4th, and 6th coils in the AX coil group.

[0071] After obtaining the magnet center frequency after modifying the coil currents, it is determined whether the change value of the magnet center frequency exceeds the predetermined center frequency scan range. If it exceeds, the remote module remotely controls to modify the center frequency of the shimming scan to the calculated magnet center frequency, and then starts the shimming scan.

[0072] Generally, it is determined whether the change value between the new and old magnet center frequencies exceeds ±10000Hz. If

[0073] it exceeds ±10000Hz, the shimming scan is still performed according to the previous center frequency scan range, and the magnetic resonance imaging system will not be able to find the center frequency. Therefore, it is necessary to re-modify the center frequency of the shimming scan to the calculated magnet center frequency, and then start the shimming scan. When the change value is less than ±10000Hz, the magnetic resonance imaging system can still find the center frequency and does not need to re-modify the center frequency of the shimming scan.

[0074] Embodiment 2

[0075] An embodiment of the present application provides a shimming method for a magnetic resonance imaging system, which is applied to the shimming control system of the magnetic resonance imaging system described in Embodiment 1 to improve the efficiency and accuracy of shimming.

[0076] Figure 1 is a flowchart of the shimming method for the magnetic resonance imaging system of the present application. Below, reference will be made to Figure 1 to describe the shimming method for the magnetic resonance imaging system of the present application in detail, including:

[0077] Step S101: In response to shimming the magnetic resonance imaging system, the remote module controls the magnetic resonance imaging system to start shimming scanning and obtains the shimming file generated after the shimming scanning ends.

[0078] Step S102: The parsing module parses the shimming file, determines the shimming scan result of the shimming file. If it passes, the shimming ends. If it does not pass, the shimming parameters of the magnetic resonance imaging system for the current shimming scan are extracted.

[0079] Step S103: Based on the shimming parameters, the shimming power supply control module configures the shimming power supply, the heater power supply, and the shimming switching module to modify the coil current.

[0080] Step S104: Repeat the above steps S101 - S103 until the shimming ends.

[0081] Embodiment 3

[0082] In this embodiment, an electronic device is further provided. The electronic device includes a processor and a memory. The memory is used to store non - transient computer - readable instructions (such as one or more computer program modules). The processor is used to run the non - transient computer - readable instructions, and when the non - transient computer - readable instructions are run by the processor, one or more steps of the above - mentioned shimming method of the magnetic resonance imaging system can be executed.

[0083] Embodiment 4

[0084] In this embodiment, a computer - readable storage medium is further provided. The storage medium is used to store non - transient computer - readable instructions. For example, when the non - transient computer - readable instructions are executed by a computer, one or more steps of the shimming method of the magnetic resonance imaging system according to the above can be executed.

[0085] The above description is only part of the embodiments of the present application and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of disclosure involved in the present application is not limited to the technical solutions formed by the specific combination of the above - mentioned technical features, and should also cover other technical solutions formed by any combination of the above - mentioned technical features or their equivalent features without departing from the above - mentioned disclosure concept. For example, the technical solutions formed by mutually replacing the above - mentioned features with the (but not limited to) technical features with similar functions disclosed in the present application.

[0086] In addition, although the operations are depicted in a particular order, this should not be construed as requiring that the operations be performed in the particular order shown or in a sequential order. In certain circumstances, multitasking and parallel processing may be advantageous. Similarly, although several specific implementation details are included in the foregoing description, these should not be construed as limitations on the scope of the present application. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented separately or in any suitable sub-combination in multiple embodiments.

[0087] Although the subject matter has been described in language specific to structural features and / or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are merely example forms of implementing the claims.

Claims

1. A shim control system for a magnetic resonance imaging system, characterized in that: include: A remote module, connected to the magnetic resonance imaging system, for remotely controlling a host of the magnetic resonance imaging system to start a shimming scanning program and obtain a shimming file, wherein the shimming file is a text data file generated after the shimming scanning is completed; An analysis module connected to the remote module is used to analyze the shimming file to determine the result of the current shimming scan and shimming parameters, wherein the shimming parameters at least include: magnet type, magnet center frequency, current coil current value and coil current correction value; A shimming power supply control module is connected to the analysis module and the shimming power supply and the heater power supply, and is used to configure the shimming power supply and the heater power supply for shimming according to the shimming parameters, and the shimming power supply and the heater power supply are used to supply power to the coil and the heater respectively; wherein the specific steps of configuring the shimming power supply and the heater power supply for shimming according to the shimming parameters include: configuring the output current of the heater power supply based on the magnet type; configuring the shimming power supply to output a first current equal to the current current value of the coil; turning on the heater, and after a first predetermined time, connecting the shimming power supply and the coil; configuring the shimming power supply to output a second current equal to the coil current correction value; after a second predetermined time, turning off the heater and the shimming power supply; The shimming switching module is connected to the shimming power supply control module and the shimming power supply, and is used to switch the coil connected to the shimming power supply.

2. The shim control system of the magnetic resonance imaging system according to claim 1, characterized in that: The shimming power supply control module is also configured to: calculate the center frequency of the magnet after modifying the coil current, and determine whether the change value of the center frequency of the magnet exceeds a predetermined center frequency scanning range; if exceeded, remotely control the center frequency of the shimming scan to be modified to the calculated center frequency of the magnet, and then start the shimming scan.

3. The shim control system of the magnetic resonance imaging system according to claim 1, characterized in that: The remote module controls the magnetic resonance imaging system through a VNC remote desktop, and remotely obtains a shim file generated after the shim scan is completed through SSH.

4. A shimming method for a magnetic resonance imaging system, applied to a shimming control system for a magnetic resonance imaging system according to any one of claims 1 to 3, characterized in that: include: Step S101: In response to shimming of the magnetic resonance imaging system, the remote module controls the magnetic resonance imaging system to start shimming scanning and obtains a shimming file generated after the shimming scanning is completed; Step S102: the parsing module parses the shimming file to determine the shimming scan result of the shimming file. If the result is passed, the shimming is terminated. If the result is not passed, the shimming parameters of the magnetic resonance imaging system for the current shimming scan are extracted. Step S103: Based on the shimming parameters, the shimming power supply control module configures the shimming power supply, the heater power supply and the shimming switching module to modify the coil current; Step S104: repeat the above steps S101-S103 until the shimming is completed.

5. An electronic device, characterized in that: include: processor; a memory having stored thereon one or more computer program instructions executed on the processor; Wherein, when the processor runs the computer program instructions, the method for shimming a magnetic resonance imaging system according to claim 4 is executed.

6. A computer-readable storage medium, characterized in that: Computer instructions are stored thereon, and when the computer instructions are executed, the steps of the field shimming method for a magnetic resonance imaging system as claimed in claim 4 are executed.

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