Magnetic resonance imaging method and apparatus

Abstract

The application relates to a magnetic resonance imaging method and device. The method comprises the following steps: determining a region of interest and a signal suppression region of a target object; determining a first adjustment parameter corresponding to the region of interest or a second adjustment parameter corresponding to the signal suppression region, the first adjustment parameter and / or the second adjustment parameter being used for adjusting a magnetic field distribution of the region of interest to produce a set difference relative to a magnetic field distribution of the signal suppression region; and generating a target magnetic field according to the first adjustment parameter and / or the second adjustment parameter. The method can better suppress fat signals and improve imaging quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of magnetic resonance, in particular to a magnetic resonance imaging method and device. BACKGROUND

[0002] Magnetic resonance imaging (MRI) technology is one of the most advanced medical imaging methods today, and has been increasingly widely used in clinical and scientific research.

[0003] In the magnetic resonance imaging process, the uniformity of the main magnetic field has a great influence on the image quality. In the case of non-uniformity of the main magnetic field, the chemical shift frequency of the fat signal may coincide with the chemical shift frequency of the signal of the metabolite of interest in part of the frequency range, and even the fat signal will suppress the signal of the metabolite of interest, resulting in poor imaging quality.

[0004] However, the current fat suppression technology cannot well solve the above problems, so it is difficult to improve the imaging quality. SUMMARY

[0005] Therefore, it is necessary to provide a magnetic resonance imaging method and device capable of well suppressing fat signals in view of the above technical problems.

[0006] A magnetic resonance imaging method, the method comprising:

[0007] determining a signal suppression region and a region of interest of a target object;

[0008] determining a first adjustment parameter corresponding to the region of interest or a second adjustment parameter corresponding to the signal suppression region; the first adjustment parameter and / or the second adjustment parameter are used to adjust the magnetic field distribution of the region of interest to produce a set difference relative to the magnetic field distribution of the signal suppression region;

[0009] generating a target magnetic field according to the first adjustment parameter and / or the second adjustment parameter.

[0010] In one embodiment, the above-mentioned determination of the first adjustment parameter corresponding to the region of interest or the second adjustment parameter of the signal suppression region comprises:

[0011] for the region of interest or the signal suppression region, obtaining an initial center frequency and a target center frequency of each region;

[0012] determining a magnetic field offset required to move the initial center frequency to the target center frequency according to a pre-established correlation between the magnetic field and the frequency;

[0013] determining the first adjustment parameter corresponding to the region of interest according to the magnetic field offset corresponding to the region of interest;

[0014] determining the second adjustment parameter corresponding to the signal suppression region according to the magnetic field offset corresponding to the signal suppression region.

[0015] In one of the embodiments, the determining the first adjustment parameter corresponding to the region of interest according to the magnetic field offset corresponding to the region of interest comprises:

[0016] determining the intermediate magnetic field distribution corresponding to the region of interest according to the magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the region of interest;

[0017] performing shimming calculation on the intermediate magnetic field distribution of the region of interest to obtain the target magnetic field distribution of the region of interest;

[0018] determining the first adjustment parameter according to the target magnetic field distribution of the region of interest.

[0019] In one of the embodiments, the determining the second adjustment parameter corresponding to the signal suppression region according to the magnetic field offset corresponding to the signal suppression region comprises:

[0020] determining the intermediate magnetic field distribution corresponding to the signal suppression region according to the magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the signal suppression region;

[0021] performing shimming calculation on the intermediate magnetic field distribution of the signal suppression region to obtain the target magnetic field distribution of the signal suppression region;

[0022] determining the second adjustment parameter according to the target magnetic field distribution of the signal suppression region.

[0023] In one of the embodiments, the generating the target magnetic field according to the first adjustment parameter and / or the second adjustment parameter comprises:

[0024] correcting the magnetic field intensity or uniformity of the region of interest according to the first adjustment parameter to adjust the magnetic field distribution of the region of interest;

[0025] correcting the magnetic field intensity or uniformity of the signal suppression region according to the second adjustment parameter to adjust the magnetic field distribution of the signal suppression region.

[0026] In one of the embodiments, the determining the region of interest and the signal suppression region of the target object comprises:

[0027] obtaining an initial magnetic resonance image of the target object;

[0028] performing image recognition on the initial magnetic resonance image to obtain the region of interest and the signal suppression region in the initial magnetic resonance image.

[0029] In one of the embodiments, the signal suppression region comprises a fat region, the signal to be suppressed comprises a fat signal, and the method further comprises:

[0030] The fat signal is suppressed by using a preset fat suppression manner to obtain a target magnetic resonance signal.

[0031] An image is reconstructed according to the target magnetic resonance signal to obtain a target magnetic resonance image.

[0032] A magnetic resonance imaging apparatus, comprising:

[0033] A region determination module is configured to determine a region of interest and a signal suppression region of a target object.

[0034] An adjustment parameter determination module is configured to determine a first adjustment parameter corresponding to the region of interest or a second adjustment parameter corresponding to the signal suppression region; the first adjustment parameter and / or the second adjustment parameter are used to adjust the magnetic field distribution of the region of interest to produce a set difference relative to the magnetic field distribution of the signal suppression region.

[0035] A magnetic field generation module is configured to generate a target magnetic field according to the first adjustment parameter and / or the second adjustment parameter.

[0036] In one of the embodiments, the adjustment parameter determination module comprises:

[0037] A frequency acquisition sub-module is configured to acquire an initial center frequency and a target center frequency of each region for the region of interest or the signal suppression region.

[0038] A magnetic field offset amount determination sub-module is configured to determine a magnetic field offset amount required for shifting the initial center frequency to the target center frequency according to a pre-established correlation between the magnetic field and the frequency.

[0039] A first parameter determination sub-module is configured to determine the first adjustment parameter corresponding to the region of interest according to the magnetic field offset amount corresponding to the region of interest.

[0040] A second parameter determination sub-module is configured to determine the second adjustment parameter corresponding to the signal suppression region according to the magnetic field offset amount corresponding to the signal suppression region.

[0041] In one of the embodiments, the first parameter determination sub-module is specifically configured to determine an intermediate magnetic field distribution of the region of interest according to the magnetic field distribution of the main magnetic field and the magnetic field offset amount corresponding to the region of interest; perform shimming calculation on the intermediate magnetic field distribution of the region of interest to obtain a target magnetic field distribution of the region of interest; and determine the first adjustment parameter according to the target magnetic field distribution of the region of interest.

[0042] In one of the embodiments, the second parameter determination submodule is specifically configured to determine the intermediate magnetic field distribution corresponding to the signal suppression region according to the pre-acquired magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the signal suppression region; perform the shimming calculation on the intermediate magnetic field distribution of the signal suppression region to obtain the target magnetic field distribution of the signal suppression region; and determine the second adjustment parameter according to the target magnetic field distribution of the signal suppression region.

[0043] In one of the embodiments, the magnetic field generation module is specifically configured to correct the magnetic field intensity or uniformity of the region of interest according to the first adjustment parameter, and adjust the magnetic field distribution of the region of interest; correct the magnetic field intensity or uniformity of the signal suppression region according to the second adjustment parameter, and adjust the magnetic field distribution of the signal suppression region.

[0044] In one of the embodiments, the region determination module is specifically configured to acquire an initial magnetic resonance image of the target object; and perform the image recognition on the initial magnetic resonance image to obtain the region of interest and the signal suppression region in the initial magnetic resonance image.

[0045] In one of the embodiments, the signal suppression region includes a fat region, and the signal to be suppressed includes a fat signal, and the device further includes:

[0046] The suppression module is configured to perform the suppression processing on the fat signal by using a preset fat suppression manner to obtain a target magnetic resonance signal.

[0047] The image reconstruction module is configured to perform the image reconstruction according to the target magnetic resonance signal to obtain a target magnetic resonance image.

[0048] A magnetic resonance imaging method, the method includes:

[0049] Determining a region of interest of a target object;

[0050] Determining a magnetic field adjustment parameter to cause the magnetic field distribution of the region of interest to have a set difference from the magnetic field distribution of the signal suppression region;

[0051] Applying the magnetic field adjustment parameter to generate a target magnetic field; and

[0052] Applying an imaging sequence under the target magnetic field to acquire a magnetic resonance image of the target object.

[0053] In one of the embodiments, the magnetic field adjustment parameter is used to adjust the magnetic field uniformity of the region of interest or the signal suppression region; or

[0054] The magnetic field adjustment parameter is used to adjust the magnetic field offset of the region of interest relative to the signal suppression region.

[0055] A computer device comprises a memory and a processor, the memory stores a computer program, and the processor implements the following steps when executing the computer program:

[0056] determining a region of interest and a signal suppression region of a target object;

[0057] determining a first adjustment parameter corresponding to the region of interest or a second adjustment parameter corresponding to the signal suppression region; the first adjustment parameter and / or the second adjustment parameter are used to adjust the magnetic field distribution of the region of interest to produce a set difference relative to the magnetic field distribution of the signal suppression region;

[0058] generating a target magnetic field according to the first adjustment parameter and / or the second adjustment parameter.

[0059] A computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the following steps:

[0060] determining a region of interest and a signal suppression region of a target object;

[0061] determining a first adjustment parameter corresponding to the region of interest or a second adjustment parameter corresponding to the signal suppression region; the first adjustment parameter and / or the second adjustment parameter are used to adjust the magnetic field distribution of the region of interest to produce a set difference relative to the magnetic field distribution of the signal suppression region;

[0062] generating a target magnetic field according to the first adjustment parameter and / or the second adjustment parameter.

[0063] The magnetic resonance imaging method and device determine a region of interest and a signal suppression region of a target object, determine a first adjustment parameter corresponding to the region of interest and a second adjustment parameter corresponding to the signal suppression region, and generate a target magnetic field according to the first adjustment parameter and / or the second adjustment parameter. Through the embodiments of the present disclosure, the first adjustment parameter and the second adjustment parameter can adjust the magnetic field distribution of the region of interest to produce a set difference relative to the magnetic field distribution of the signal suppression region, so as to expand the frequency difference between the target center frequency of the signal of interest and the target center frequency of the signal to be suppressed, reduce the frequency coincidence range between the signal to be suppressed and the signal of interest, thereby reducing the influence of the signal to be suppressed on the signal of interest, well suppressing the signal to be suppressed, and further improving the imaging quality. BRIEF DESCRIPTION OF DRAWINGS

[0064] Figure 1 An application environment diagram of the magnetic resonance imaging method in one embodiment;

[0065] Figure 2 A flowchart of the magnetic resonance imaging method in one embodiment;

[0066] Figure 3aFig. 1 is a schematic diagram of a signal suppression region in one embodiment;

[0067] Figure 3b Fig. 2 is a schematic diagram of a signal suppression region in another embodiment;

[0068] Figure 4a Fig. 3 is a schematic diagram of the chemical shift frequency of water signal and fat signal in one embodiment;

[0069] Figure 4b Fig. 4 is a schematic diagram of the chemical shift frequency of water signal and fat signal in another embodiment;

[0070] Figure 5 Fig. 5 is a schematic diagram of the flow of determining the first adjustment parameter and the second adjustment parameter in one embodiment;

[0071] Figure 6 Fig. 6 is a schematic diagram of the flow of determining the first adjustment parameter in one embodiment;

[0072] Figure 7 Fig. 7 is a schematic diagram of the flow of determining the second adjustment parameter in one embodiment;

[0073] Figure 8 Fig. 8 is a schematic diagram of the flow of adjusting the magnetic field distribution in one embodiment;

[0074] Figure 9 Fig. 9 is a schematic diagram of the flow of obtaining the region of interest and the signal suppression region in one embodiment;

[0075] Figure 10 Fig. 10 is a schematic diagram of the flow of the magnetic resonance imaging method in another embodiment;

[0076] Figure 11 Fig. 11 is a schematic diagram of the flow of the magnetic resonance imaging method in yet another embodiment;

[0077] Figure 12 Fig. 12 is a structural block diagram of the magnetic resonance imaging apparatus in one embodiment;

[0078] Figure 13 Fig. 13 is an internal structural diagram of the computer device in one embodiment. DETAILED DESCRIPTION

[0079] In order to make the purpose, technical scheme and advantages of the present application clearer, further detailed description will be given to the present application in combination with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0080] The magnetic resonance imaging method provided by the present application can be applied to, for example, Figure 1The application environment shown. The application environment can include a computer device 101 and an MR (Magnetic Resonance) device 102. Among them, the computer device 101 can communicate with the magnetic resonance device 102 through the network. The above-mentioned computer device 101 can be, but is not limited to, various personal computers, notebook computers and tablet computers.

[0081] The application environment can also include a controller 103, which can include a processor and a memory, and the processor is directly or indirectly communicatively connected with the computer device 101, the magnetic resonance device 102 and the memory through a bus. The above-mentioned controller 103 can be realized by an independent service and an apparatus or a server cluster composed of multiple servers. The processor included in the controller 103 can be of any type, with one or more processing cores. It can perform single-threaded or multi-threaded operations for parsing instructions to perform data acquisition, logical operation functions, and issuing operation processing results. The memory included in the controller 103 can include a non-volatile computer readable storage medium, such as at least one disk storage device, a flash storage device, a distributed storage device remotely arranged with respect to the processor, or other non-volatile solid-state storage device.

[0082] In one embodiment, as Figure 2 shown, a magnetic resonance imaging method is provided, which is applied to the computer device in Figure 1 for example, including the following steps:

[0083] Step 201, determining a region of interest and a signal suppression region of a target object.

[0084] The computer device can acquire a magnetic resonance image and display the magnetic resonance image, which can be a positioning image, a pre-scan image or a historical scan image of the target object. Then, the user can delineate the region of interest and the signal suppression region in the magnetic resonance image. As Figure 3a and 3b shown, the user delineates the abdominal fat region, i.e. the ring-shaped region in the figure, as the signal suppression region in the magnetic resonance image, and the region within the ring-shaped region is the region of interest. Optionally, the signal suppression region can be divided into multiple regions. In an embodiment, the signal suppression region is delineated according to the inner and outer boundaries of the abdominal fat region, respectively; at the same time, considering that the fat thickness and the magnetic field distribution of different regions of the target object exist slight differences, the signal suppression region can be divided into multiple regions along the circumferential direction of the region of interest. In another embodiment, as Figure 3bAs shown, the signal suppression region is set to different widths (along the radial direction of the annular region in the figure) according to the difference in the thickness of the abdominal fat region along the radial direction: a wider signal suppression region is set for a region where the fat region is thicker; and a narrower signal suppression region is set for a region where the fat region is thinner.

[0085] The magnetic resonance image can be pre-stored in the computer device or acquired by the computer device from a magnetic resonance device or a PACS server. The magnetic resonance image is used to determine the region of interest and the signal suppression region, and is preferably a historical magnetic resonance image of the target object, but can also be a historical magnetic resonance image of another object. The magnetic resonance image is not limited in the embodiments of the present disclosure.

[0086] In step 202, the first adjustment parameter corresponding to the region of interest or the second adjustment parameter corresponding to the signal suppression region is determined.

[0087] The first adjustment parameter and / or the second adjustment parameter are used to adjust the magnetic field distribution of the region of interest to produce a set difference relative to the magnetic field distribution of the signal suppression region. Optionally, in the case where the signal suppression region is divided into multiple regions, multiple sets of second adjustment parameters can also be set, i.e., a corresponding second adjustment parameter is set for each signal suppression region, and the second adjustment parameters belonging to different signal suppression regions can be set to be the same or different.

[0088] In the case of a main magnetic field inhomogeneity, the chemical shift frequency of the signal to be suppressed can coincide with the chemical shift frequency of the signal of the metabolite of interest in a partial frequency range, and even the signal to be suppressed can suppress the signal of the metabolite of interest, resulting in poor imaging quality. Therefore, to reduce the coincidence frequency of the chemical shift frequency of the signal to be suppressed and the chemical shift frequency of the signal of the metabolite of interest, and to avoid the signal to be suppressed from suppressing the signal of the metabolite of interest, the difference between the center frequency of the signal to be suppressed and the center frequency of the signal of the metabolite of interest can be expanded, and the first adjustment parameter of the region of interest or the second adjustment parameter of the signal suppression region is determined according to the expanded center frequency.

[0089] For example, the region of interest mainly contains water, and the magnetic resonance signal generated thereby is the signal of water protons (water signal); and the signal suppression region mainly contains fat, and the magnetic resonance signal generated thereby is the signal of hydrogen protons contained in fat (fat signal). In theory, the difference between the center frequencies of the water signal and the fat signal is proportional to the main magnetic field B0, and the center frequencies of the water signal and the fat signal are 4.7 ppm and 1.3 ppm, respectively, and the difference between the center frequencies is 3.4 ppm, as shown in Figure 4aAs shown. To amplify the difference in center frequencies between the water and fat signals, it is necessary to increase the center frequency of the water signal and decrease the center frequency of the fat signal. Therefore, a first adjustment parameter for the water signal is determined based on the increased center frequency, or a second adjustment parameter for the fat signal is determined based on the decreased center frequency. In this way, the frequency of the main magnetic field is changed by altering the first and second adjustment parameters, thereby changing the difference in center frequencies between the water and fat signals.

[0090] Step 203: Generate the target magnetic field according to the first adjustment parameter and / or the second adjustment parameter.

[0091] After determining the first adjustment parameter and / or the second adjustment parameter, the computer equipment controls the magnetic resonance imaging (MRI) device to scan the target object. During MRI, a target magnetic field is generated based on the first and / or second adjustment parameters. The first adjustment parameter is used to adjust the magnetic field distribution in the region of interest, or the second adjustment parameter is used to adjust the magnetic field distribution in the signal suppression region. This ensures that the target center frequency of the signal of interest generated in the region of interest has a preset frequency difference from the target center frequency of the signal to be suppressed generated in the signal suppression region. This disclosure does not limit how the magnetic field distribution is adjusted based on the magnetic field parameters.

[0092] Optionally, steps 201-203 above can be applied to one or more layers of the target object. For example, different regions of interest and signal suppression regions can be divided for different layers of a target region, that is, different layers can be processed separately.

[0093] Optionally, after generating the target magnetic field, an imaging sequence can be used to excite the target object to generate a magnetic resonance image of the target object.

[0094] like Figure 4b As shown, after adjusting the magnetic field distribution, the center frequency difference between the water signal and the fat signal is 7 ppm.

[0095] In the aforementioned magnetic resonance imaging method, a region of interest (ROI) and a signal suppression region (PSG) of the target object are determined; a first adjustment parameter corresponding to the ROI or a second adjustment parameter corresponding to the PSG is determined; and a target magnetic field is generated based on the first and / or second adjustment parameters. Through the embodiments of this disclosure, the first and second adjustment parameters can adjust the magnetic field distribution of the ROI relative to the magnetic field distribution of the PSG to create a predetermined difference. Therefore, the frequency difference between the target center frequency of the signal of interest and the target center frequency of the signal to be suppressed can be expanded, reducing the frequency overlap range between the signal to be suppressed and the signal of interest, thereby reducing the influence of the signal to be suppressed on the signal of interest, effectively suppressing the signal to be suppressed, and thus improving imaging quality.

[0096] In one embodiment, as shown in Figure 5 The step of determining the first adjustment parameter corresponding to the region of interest or the second adjustment parameter corresponding to the signal suppression region can include:

[0097] In step 301, the initial center frequency and the target center frequency of each region are obtained for the region of interest or the signal suppression region.

[0098] For the region of interest, the computer device obtains the initial center frequency and the target center frequency of the region of interest. For example, the computer device obtains the initial center frequency of the region of interest as 4.7ppm, and receives the target center frequency input by the user as 8ppm.

[0099] For the signal suppression region, the computer device obtains the initial center frequency and the target center frequency of the signal suppression region. For example, the computer device obtains the initial center frequency of the signal suppression region as 1.3ppm, and receives the target center frequency input by the user as 1ppm.

[0100] In step 302, the magnetic field offset required to move the initial center frequency to the target center frequency is determined according to the pre-established correlation between the magnetic field and the frequency.

[0101] The correlation between the magnetic field and the frequency is pre-established in the computer device. After obtaining the initial center frequency and the target center frequency of each region, the computer device determines the frequency change amount to move the initial center frequency to the target center frequency, and then determines the magnetic field offset according to the correlation between the magnetic field and the frequency and the frequency change amount.

[0102] For example, for the region of interest, the frequency change amount to move the initial center frequency to the target center frequency is 3.3ppm, and the magnetic field offset is determined as △B1 according to the correlation between the magnetic field and the frequency and the frequency change amount of 3.3ppm. For the signal suppression region, the frequency change amount to move the initial center frequency to the target center frequency is 0.3ppm, and the magnetic field offset is determined as △B2 according to the correlation between the magnetic field and the frequency and the frequency change amount of 0.3ppm.

[0103] In step 303, the first adjustment parameter corresponding to the region of interest is determined according to the magnetic field offset corresponding to the region of interest.

[0104] According to the magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the region of interest, the first adjustment parameter corresponding to the region of interest can be determined. For example, the first adjustment parameter is determined according to the main magnetic field B0 and the magnetic field offset △B1.

[0105] In practical applications, some coils for adjusting the magnetic field distribution are also arranged in the scanning cavity of the magnetic resonance device. The first adjustment parameter can include the current, power, etc. of the coil corresponding to the position of the region of interest. The embodiments of the present disclosure do not limit the first adjustment parameter.

[0106] In step 304, the second adjustment parameter corresponding to the signal suppression region is determined according to the magnetic field offset corresponding to the signal suppression region.

[0107] According to the magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the signal suppression region, the second adjustment parameter corresponding to the signal suppression region can be determined. For example, the second adjustment parameter is determined according to the main magnetic field B0 and the magnetic field offset ΔB2.

[0108] The above-mentioned second adjustment parameter can include the current, power, etc. of the coil corresponding to the position of the signal suppression region. The embodiments of the present disclosure do not limit the second adjustment parameter.

[0109] In the above-mentioned embodiments, the initial center frequency and the target center frequency of each region are obtained for the region of interest or the signal suppression region; the magnetic field offset required to move the initial center frequency to the target center frequency is determined according to the pre-established correlation between the magnetic field and the frequency; the first adjustment parameter corresponding to the region of interest is determined according to the magnetic field offset corresponding to the region of interest; and the second adjustment parameter corresponding to the signal suppression region is determined according to the magnetic field offset corresponding to the signal suppression region. Through the embodiments of the present disclosure, the magnetic field offset can be determined according to the frequency change amount, and then the adjustment parameter is determined, so that the magnetic field distribution of the region of interest and the signal suppression region can be adjusted according to the adjustment parameter in the future, and then the frequency difference between the signal of interest and the signal to be suppressed is expanded, thereby well suppressing the signal to be suppressed.

[0110] In one embodiment, as shown in Figure 6 The step of determining the first adjustment parameter corresponding to the region of interest according to the magnetic field offset corresponding to the region of interest can include:

[0111] In step 3031, the intermediate magnetic field distribution corresponding to the region of interest is determined according to the pre-acquired magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the region of interest.

[0112] Optionally, the magnetic resonance device 102 performs the imaging process by exciting the magnetic resonance signals through an imaging sequence, and the measurement radio frequency signals can be added to the imaging sequence in synchronization with the imaging radio frequency signals. The imaging magnetic resonance signals are excited through the imaging radio frequency signals, and the measurement magnetic resonance signals are excited through the measurement signals, so that the real-time magnetic field distribution measurement is realized. In an embodiment, a set of measurement magnetic resonance signals are collected more densely, and then in the step of processing the measurement magnetic resonance signals to obtain the actual magnetic field strength, a physical model of the actual magnetic field strength can be established based on the densely collected set of measurement magnetic resonance signals, the physical model can simulate the change of the actual magnetic field strength, so that the distribution of the magnetic field strength in a specific time interval can be estimated and predicted, that is, the magnetic field distribution of the main magnetic field is obtained.

[0113] The computer device adjusts the magnetic field distribution of the main magnetic field according to the magnetic field offset corresponding to the region of interest, to obtain an intermediate magnetic field distribution corresponding to the region of interest.

[0114] For example, the magnetic field distribution of the main magnetic field is added to the magnetic field offset corresponding to the region of interest to obtain the intermediate magnetic field distribution corresponding to the region of interest. The adjustment method is not limited in the embodiments of the present disclosure.

[0115] In step 3032, the intermediate magnetic field distribution of the region of interest is subjected to shimming calculation to obtain a target magnetic field distribution of the region of interest.

[0116] Since the main magnetic field can be non-uniform, the intermediate magnetic field distribution of the region of interest obtained by adjusting the magnetic field distribution of the main magnetic field can also be non-uniform. In this case, the intermediate magnetic field distribution of the region of interest is subjected to shimming calculation, and a more uniform target magnetic field distribution of the region of interest can be obtained.

[0117] In step 3033, the first adjustment parameter is determined according to the target magnetic field distribution of the region of interest.

[0118] According to the target magnetic field distribution of the region of interest, the current, power, etc. of the coil corresponding to the position of the region of interest are determined to obtain the first adjustment parameter.

[0119] In the above embodiments, the intermediate magnetic field distribution corresponding to the region of interest is determined according to the pre-acquired magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the region of interest; the target magnetic field distribution of the region of interest is obtained by subjecting the intermediate magnetic field distribution of the region of interest to shimming calculation; and the first adjustment parameter is determined according to the target magnetic field distribution of the region of interest. Through the embodiments of the present disclosure, the intermediate magnetic field distribution of the region of interest is subjected to shimming calculation, so that the frequency range of the interest signal generated by the region of interest can be narrowed, thereby reducing the frequency coincidence range of the interest signal and the to-be-suppressed signal, and the to-be-suppressed signal can be better suppressed.

[0120] In one embodiment, as shown in Figure 7 The step of determining the second adjustment parameter corresponding to the signal suppression region according to the magnetic field offset corresponding to the signal suppression region can include:

[0121] At step 3041, the intermediate magnetic field distribution corresponding to the signal suppression region is determined according to the magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the signal suppression region.

[0122] The computer device adjusts the magnetic field distribution of the main magnetic field according to the magnetic field offset corresponding to the signal suppression region to obtain the intermediate magnetic field distribution corresponding to the signal suppression region.

[0123] For example, the magnetic field distribution of the main magnetic field is subtracted from the magnetic field offset corresponding to the signal suppression region to obtain the intermediate magnetic field distribution corresponding to the signal suppression region. The adjustment manner is not limited in the embodiments of the present disclosure.

[0124] At step 3042, the target magnetic field distribution of the signal suppression region is obtained by shimming calculation on the intermediate magnetic field distribution of the signal suppression region.

[0125] Since the main magnetic field can be non-uniform, the intermediate magnetic field distribution of the signal suppression region obtained by adjusting the magnetic field distribution of the main magnetic field can also be non-uniform. In this case, the target magnetic field distribution of the signal suppression region that is more uniform can be obtained by shimming calculation on the intermediate magnetic field distribution of the signal suppression region.

[0126] At step 3043, the second adjustment parameter is determined according to the target magnetic field distribution of the signal suppression region.

[0127] The current, power, etc. of the coil corresponding to the position of the signal suppression region is determined according to the target magnetic field distribution of the signal suppression region to obtain the second adjustment parameter.

[0128] In the above embodiments, the intermediate magnetic field distribution corresponding to the signal suppression region is determined according to the magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the signal suppression region; the target magnetic field distribution of the signal suppression region is obtained by shimming calculation on the intermediate magnetic field distribution of the signal suppression region; and the second adjustment parameter is determined according to the target magnetic field distribution of the signal suppression region. By shimming calculation on the intermediate magnetic field distribution of the signal suppression region, the frequency range of the to-be-suppressed signal generated in the signal suppression region can be narrowed, so as to reduce the frequency coincidence range of the signal of interest and the to-be-suppressed signal, and thus the to-be-suppressed signal can be better suppressed.

[0129] In one embodiment, as shown in Figure 8 The step of generating the target magnetic field according to the first adjustment parameter and / or the second adjustment parameter can include:

[0130] In step 401, the magnetic field intensity or uniformity of the region of interest is corrected according to the first adjustment parameter, and the magnetic field distribution of the region of interest is adjusted.

[0131] The first adjustment parameter includes the current, power, etc. of the shim coil corresponding to the position of the region of interest. The computer device controls the magnetic resonance device to input the current according to the first adjustment parameter, so that the magnetic field of the region of interest can be applied. The magnetic field of the region of interest is superimposed with the main magnetic field, so that the magnetic field intensity or uniformity of the region of interest can be corrected, and the magnetic field distribution of the region of interest is adjusted.

[0132] In step 402, the magnetic field intensity or uniformity of the signal suppression region is corrected according to the second adjustment parameter, and the magnetic field distribution of the signal suppression region is adjusted.

[0133] The second adjustment parameter includes the current, power, etc. of the shim coil corresponding to the position of the signal suppression region. The computer device controls the magnetic resonance device to input the current according to the second adjustment parameter, so that the magnetic field of the signal suppression region can be applied. The magnetic field of the signal suppression region is superimposed with the main magnetic field, so that the magnetic field intensity or uniformity of the signal suppression region can be corrected, and the magnetic field distribution of the signal suppression region is adjusted.

[0134] In the above embodiment, the magnetic field intensity or uniformity of the region of interest is corrected according to the first adjustment parameter, and the magnetic field distribution of the region of interest is adjusted; the magnetic field intensity or uniformity of the signal suppression region is corrected according to the second adjustment parameter, and the magnetic field distribution of the signal suppression region is adjusted, which can expand the frequency difference between the signal of interest and the signal to be suppressed, so that the signal to be suppressed can be well suppressed.

[0135] In one embodiment, as shown in FIG. 5, the above step of determining the region of interest and the signal suppression region of the target object can include: Figure 9

[0136] In step 501, an initial magnetic resonance image of the target object is acquired.

[0137] The computer device can acquire the initial magnetic resonance image of the target object from the magnetic resonance device, or acquire the initial magnetic resonance image of the target object from the PACS server. The present disclosure does not limit this.

[0138] In step 502, image recognition is performed on the initial magnetic resonance image to obtain the region of interest and the signal suppression region in the initial magnetic resonance image.

[0139] ​The computer device can pre-train the region of interest recognition model, input the initial magnetic resonance image into the region of interest recognition model, and obtain the region of interest in the initial magnetic resonance image output by the region of interest recognition model. At the same time, the computer device can also train the suppression region recognition model, input the initial magnetic resonance image into the suppression region recognition model, and obtain the signal suppression region in the initial magnetic resonance image output by the suppression region recognition model.

[0140] The region of interest recognition model and the suppression region recognition model can be deep learning models. In actual application, the region of interest and the signal suppression region in the initial magnetic resonance image can also be obtained in other ways, which are not limited in the embodiments of the present disclosure.

[0141] In the above embodiments, the initial magnetic resonance image of the target object is obtained, and the initial magnetic resonance image is subjected to image recognition to obtain the region of interest and the signal suppression region in the initial magnetic resonance image. Through the embodiments of the present disclosure, the region of interest and the signal suppression region are automatically recognized, and the acquisition efficiency of the region of interest and the signal suppression region can be improved.

[0142] In one embodiment, as shown in Figure 10 The signal suppression region includes a fat region, and the signal to be suppressed includes a fat signal. Based on the above embodiments, the embodiments of the present disclosure can further include the following steps.

[0143] In step 204, a preset fat suppression method is used to suppress the fat signal to obtain a target magnetic resonance signal.

[0144] The preset fat suppression method includes at least one of a saturation band fat suppression method, a frequency-selective fat suppression method, an IR flip recovery method, a frequency-selective water excitation method, and a water-fat separation method.

[0145] After the computer device expands the frequency difference between the fat signal and the signal of interest, at least one of the preset fat suppression parameters, such as the saturation band fat suppression method, the frequency-selective fat suppression method, the IR flip recovery method, the frequency-selective water excitation method, and the water-fat separation method, is used to suppress the fat signal to obtain a target magnetic resonance signal.

[0146] In step 205, an image is reconstructed according to the target magnetic resonance signal to obtain a target magnetic resonance image.

[0147] The computer device can use various image reconstruction algorithms to reconstruct the target magnetic resonance signal to obtain a target magnetic resonance image.

[0148] In the above embodiments, the fat signal is suppressed by using a preset fat suppression manner to obtain a target magnetic resonance signal; and an image is reconstructed according to the target magnetic resonance signal to obtain a target magnetic resonance image. Through the embodiments of the present disclosure, the computer device can better suppress the fat signal after expanding the frequency difference between the fat signal and the signal of interest, thereby improving the imaging quality of the target magnetic resonance image.

[0149] In one embodiment, as shown in FIG. 1, a magnetic resonance imaging method can include the following steps: Figure 11

[0150] Step 601, determining a region of interest of a target object.

[0151] The computer device can acquire a magnetic resonance image and display the magnetic resonance image. Then, a user can delineate a region of interest in the magnetic resonance image. Alternatively, the computer device acquires an initial magnetic resonance image of the target object, and performs image recognition on the initial magnetic resonance image to obtain the region of interest in the initial magnetic resonance image. The determination method of the region of interest is not limited in the embodiments of the present disclosure.

[0152] Step 602, determining a magnetic field adjustment parameter to cause a magnetic field distribution of the region of interest to have a set difference from a magnetic field distribution of a signal suppression region.

[0153] For the region of interest, the computer device acquires an initial center frequency and a target center frequency of each region; determines a magnetic field offset required to move the initial center frequency to the target center frequency according to a pre-established correlation between the magnetic field and the frequency; and determines the magnetic field adjustment parameter according to the magnetic field offset corresponding to the region of interest. Optionally, the initial center frequency of each region is determined by detecting the magnetic field distribution, and the magnetic field distribution can be obtained by: providing a measurement radio frequency signal to excite a monitoring sample and generate a measurement magnetic resonance signal corresponding to the imaging magnetic field, and collecting the measurement magnetic resonance signal; and obtaining the actual magnetic field strength according to the measurement magnetic resonance signal based on the magnetic resonance principle, thereby obtaining the magnetic field distribution. The measurement magnetic resonance signal includes frequency information and phase information.

[0154] Step 603, applying the magnetic field adjustment parameter to generate a target magnetic field; and applying an imaging sequence under the target magnetic field to acquire a magnetic resonance image of the target object.

[0155] The magnetic field adjustment parameter is used to adjust the magnetic field uniformity of the region of interest or the signal suppression region; or the magnetic field adjustment parameter is used to adjust the magnetic field offset of the region of interest relative to the signal suppression region. For example, the magnetic field adjustment parameter can be the current of the shimming coil.

[0156] The magnetic resonance device applies the magnetic field adjustment parameter to generate a target magnetic field and acquires a magnetic resonance image of the target object.​

[0157] In the above embodiments, a region of interest of the target object is determined, a magnetic field adjustment parameter is determined to cause a magnetic field distribution of the region of interest to have a set difference from a magnetic field distribution of the signal suppression region, the magnetic field adjustment parameter is applied to generate a target magnetic field, and an imaging sequence is applied under the target magnetic field to acquire a magnetic resonance image of the target object. Through the embodiments of the present disclosure, the frequency difference between the target center frequency of the signal of interest and the target center frequency of the signal to be suppressed can be expanded, the frequency coincidence range between the signal to be suppressed and the signal of interest can be reduced, the influence of the signal to be suppressed on the signal of interest can be reduced, the signal to be suppressed can be well suppressed, and thus the imaging quality can be improved.

[0158] It should be understood that, although Figure 2 to Figure 11 the steps in the flowcharts are shown in sequence according to the arrows, the steps are not necessarily executed in sequence according to the arrows. Unless otherwise specified herein, the execution of the steps is not strictly limited in sequence, and the steps can be executed in other sequences. Moreover, Figure 2 to Figure 11 at least part of the steps in the flowcharts can include multiple steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of the steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or steps or stages in other steps.

[0159] In one embodiment, as Figure 12 shown, a magnetic resonance imaging apparatus is provided, comprising:

[0160] The region determination module 701 is configured to determine a region of interest and a signal suppression region of a target object.

[0161] The adjustment parameter determination module 702 is configured to determine a first adjustment parameter corresponding to the region of interest or a second adjustment parameter corresponding to the signal suppression region, wherein the first adjustment parameter and / or the second adjustment parameter is used to adjust the magnetic field distribution of the region of interest to have a set difference from the magnetic field distribution of the signal suppression region.

[0162] The magnetic field generation module 703 is configured to generate a target magnetic field according to the first adjustment parameter and / or the second adjustment parameter.

[0163] Optionally, the magnetic resonance imaging apparatus can further comprise an imaging sequence excitation module, and the aforementioned region determination module 701, adjustment parameter determination module 702, and magnetic field generation module 703 together constitute a pre-adjustment module arranged before the imaging sequence excitation module. After the target magnetic field is generated, the imaging sequence excitation module generates an imaging sequence to excite the target object to generate a magnetic resonance image of the target object.

[0164] In one of the embodiments, the adjustment parameter determination module 702 comprises:

[0165] a frequency acquisition sub-module, configured to acquire an initial center frequency and a target center frequency of each region for the region of interest or the signal suppression region;

[0166] a magnetic field offset amount determination sub-module, configured to determine a magnetic field offset amount required for shifting the initial center frequency to the target center frequency according to a pre-established correlation between the magnetic field and the frequency;

[0167] a first parameter determination sub-module, configured to determine a first adjustment parameter corresponding to the region of interest according to the magnetic field offset amount corresponding to the region of interest;

[0168] a second parameter determination sub-module, configured to determine a second adjustment parameter corresponding to the signal suppression region according to the magnetic field offset amount corresponding to the signal suppression region.

[0169] In one of the embodiments, the first parameter determination sub-module is specifically configured to determine an intermediate magnetic field distribution corresponding to the region of interest according to a pre-acquired magnetic field distribution of a main magnetic field and the magnetic field offset amount corresponding to the region of interest; perform shimming calculation on the intermediate magnetic field distribution of the region of interest to obtain a target magnetic field distribution of the region of interest; and determine the first adjustment parameter according to the target magnetic field distribution of the region of interest.

[0170] In one of the embodiments, the second parameter determination sub-module is specifically configured to determine an intermediate magnetic field distribution corresponding to the signal suppression region according to a pre-acquired magnetic field distribution of a main magnetic field and the magnetic field offset amount corresponding to the signal suppression region; perform shimming calculation on the intermediate magnetic field distribution of the signal suppression region to obtain a target magnetic field distribution of the signal suppression region; and determine the second adjustment parameter according to the target magnetic field distribution of the signal suppression region.

[0171] In one of the embodiments, the magnetic field adjustment module 703 is specifically configured to correct the magnetic field intensity or uniformity of the region of interest according to the first adjustment parameter, and adjust the magnetic field distribution of the region of interest; correct the magnetic field intensity or uniformity of the signal suppression region according to the second adjustment parameter, and adjust the magnetic field distribution of the signal suppression region.

[0172] In one of the embodiments, the region determination module 701 is specifically configured to acquire an initial magnetic resonance image of a target object; and perform image recognition on the initial magnetic resonance image to obtain the region of interest and the signal suppression region in the initial magnetic resonance image.

[0173] In one of the embodiments, the signal suppression region comprises a fat region, and the signal to be suppressed comprises a fat signal, and the device further comprises:

[0174] The inhibition module is configured to perform inhibition processing on the fat signal by using a preset fat inhibition manner to obtain a target magnetic resonance signal.

[0175] The image reconstruction module is configured to perform image reconstruction according to the target magnetic resonance signal to obtain a target magnetic resonance image.

[0176] The specific limitations on the magnetic resonance imaging apparatus can refer to the limitations on the magnetic resonance imaging method in the foregoing, which will not be repeated here. Each module in the above magnetic resonance imaging apparatus can be realized by software, hardware, and combinations thereof, in whole or in part. The above modules can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the computer device in software form, so as to be called and executed by the processor to perform the operations corresponding to the above modules.

[0177] In one embodiment, a computer device is provided, which can be a terminal, and an internal structure diagram thereof can be as shown in Figure 13 The computer device includes a processor, a memory, a communication interface, a display screen, and an input device connected through a system bus. The processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The communication interface of the computer device is configured to perform wired or wireless communication with an external terminal. The wireless communication can be achieved by WIFI, an operator network, NFC (near field communication), or other technologies. The computer program is executed by the processor to implement a magnetic resonance imaging method. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer overlaid on the display screen, or can be a key, trackball, or touchpad arranged on the shell of the computer device, or can be an external keyboard, touchpad, or mouse, etc.

[0178] Those skilled in the art can understand that Figure 13 the structure shown in the above

[0179] In one embodiment, a computer device is provided, which includes a memory and a processor, and the memory stores a computer program. The processor executes the computer program to implement the following steps:

[0180] determining a region of interest and a signal inhibition region of the target object;

[0181] determining a first adjustment parameter of the region of interest or a second adjustment parameter corresponding to the signal suppression region; the first adjustment parameter and / or the second adjustment parameter is used to adjust the magnetic field distribution of the region of interest to produce a set difference relative to the magnetic field distribution of the signal suppression region;

[0182] generating a target magnetic field according to the first adjustment parameter and / or the second adjustment parameter.

[0183] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0184] obtaining an initial center frequency and a target center frequency of each region for the region of interest or the signal suppression region;

[0185] determining a magnetic field offset required to move the initial center frequency to the target center frequency according to a pre-established correlation between the magnetic field and the frequency;

[0186] determining the first adjustment parameter corresponding to the region of interest according to the magnetic field offset corresponding to the region of interest;

[0187] determining the second adjustment parameter corresponding to the signal suppression region according to the magnetic field offset corresponding to the signal suppression region.

[0188] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0189] determining an intermediate magnetic field distribution corresponding to the region of interest according to the magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the region of interest;

[0190] performing shimming calculation on the intermediate magnetic field distribution of the region of interest to obtain a target magnetic field distribution of the region of interest;

[0191] determining the first adjustment parameter according to the target magnetic field distribution of the region of interest.

[0192] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0193] determining an intermediate magnetic field distribution corresponding to the signal suppression region according to the magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the signal suppression region;

[0194] performing shimming calculation on the intermediate magnetic field distribution of the signal suppression region to obtain a target magnetic field distribution of the signal suppression region;

[0195] determining the second adjustment parameter according to the target magnetic field distribution of the signal suppression region.

[0196] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0197] adjusting the magnetic field distribution of the region of interest according to the correction of the magnetic field strength or uniformity of the region of interest according to the first adjustment parameter;

[0198] adjusting the magnetic field distribution of the signal suppression region according to the correction of the magnetic field strength or uniformity of the signal suppression region according to the second adjustment parameter.

[0199] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0200] obtaining an initial magnetic resonance image of the target object;

[0201] performing image recognition on the initial magnetic resonance image to obtain a region of interest and a signal suppression region in the initial magnetic resonance image.

[0202] In one embodiment, the signal suppression region includes a fat region, and the signal to be suppressed includes a fat signal, and the processor, when executing the computer program, further implements the following steps:

[0203] suppressing the fat signal by using a preset fat suppression method to obtain a target magnetic resonance signal;

[0204] performing image reconstruction according to the target magnetic resonance signal to obtain a target magnetic resonance image.

[0205] In one embodiment, a computer readable storage medium is provided, and the computer readable storage medium stores a computer program, and the computer program, when executed by a processor, implements the following steps:

[0206] determining a region of interest and a signal suppression region of a target object;

[0207] determining a first adjustment parameter corresponding to the region of interest or a second adjustment parameter corresponding to the signal suppression region; the first adjustment parameter and / or the second adjustment parameter are used to adjust the magnetic field distribution of the region of interest to produce a set difference relative to the magnetic field distribution of the signal suppression region;

[0208] generating a target magnetic field according to the first adjustment parameter and / or the second adjustment parameter.

[0209] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0210] for the region of interest or the signal suppression region, obtaining an initial center frequency and a target center frequency of each region;

[0211] determining a magnetic field offset required to move the initial center frequency to the target center frequency according to a pre-established correlation between the magnetic field and the frequency;

[0212] determining a first adjustment parameter corresponding to the region of interest according to the magnetic field offset corresponding to the region of interest;

[0213] determine the second adjustment parameter corresponding to the signal suppression region according to the magnetic field offset corresponding to the signal suppression region.

[0214] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0215] determine the intermediate magnetic field distribution corresponding to the region of interest according to the magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the region of interest obtained in advance;

[0216] perform shimming calculation on the intermediate magnetic field distribution of the region of interest to obtain the target magnetic field distribution of the region of interest;

[0217] determine the first adjustment parameter according to the target magnetic field distribution of the region of interest.

[0218] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0219] determine the intermediate magnetic field distribution corresponding to the signal suppression region according to the magnetic field distribution of the main magnetic field and the magnetic field offset corresponding to the signal suppression region obtained in advance;

[0220] perform shimming calculation on the intermediate magnetic field distribution of the signal suppression region to obtain the target magnetic field distribution of the signal suppression region;

[0221] determine the second adjustment parameter according to the target magnetic field distribution of the signal suppression region.

[0222] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0223] correct the magnetic field intensity or uniformity of the region of interest according to the first adjustment parameter, and adjust the magnetic field distribution of the region of interest;

[0224] correct the magnetic field intensity or uniformity of the signal suppression region according to the second adjustment parameter, and adjust the magnetic field distribution of the signal suppression region.

[0225] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0226] obtain an initial magnetic resonance image of the target object;

[0227] perform image recognition on the initial magnetic resonance image to obtain the region of interest and the signal suppression region in the initial magnetic resonance image.

[0228] In one embodiment, the signal suppression region includes a fat region, and the signal to be suppressed includes a fat signal, and the computer program, when executed by the processor, further implements the following steps:

[0229] The fat signal is suppressed by using a preset fat suppression method to obtain a target magnetic resonance signal.

[0230] An image is reconstructed according to the target magnetic resonance signal to obtain a target magnetic resonance image.

[0231] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer readable storage medium. When the computer program is executed, the processes of the above-mentioned embodiments can be included. Any reference to memory, storage, database or other medium used in each embodiment provided by the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0232] Each technical feature of the above embodiments can be combined arbitrarily. In order to make the description simple, all possible combinations of each technical feature in the above embodiments are not described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0233] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, some modifications and improvements can be made, which are all within the scope of the present application. Therefore, the scope of the patent of the present application should be subject to the appended claims.

Claims

1. A magnetic resonance imaging method, characterized by, The method comprises: determining a region of interest and a signal suppression region of a target object; determining a first adjustment parameter corresponding to the region of interest or a second adjustment parameter corresponding to the signal suppression region, the first adjustment parameter and / or the second adjustment parameter being used to adjust the magnetic field distribution of the region of interest to produce a set difference relative to the magnetic field distribution of the signal suppression region; generating a target magnetic field according to the first adjustment parameter and / or the second adjustment parameter; wherein the determination of the first adjustment parameter corresponding to the region of interest or the second adjustment parameter corresponding to the signal suppression region comprises: for the region of interest or the signal suppression region, obtaining an initial center frequency and a target center frequency of each region; determining a magnetic field offset required to shift the initial center frequency to the target center frequency according to a pre-established correlation between the magnetic field and the frequency; determining the first adjustment parameter corresponding to the region of interest according to the magnetic field offset corresponding to the region of interest; and / or determining the second adjustment parameter corresponding to the signal suppression region according to the magnetic field offset corresponding to the signal suppression region.

2. The method of claim 1, wherein, The determination of the first adjustment parameter corresponding to the region of interest according to the magnetic field offset corresponding to the region of interest comprises: determining an intermediate magnetic field distribution corresponding to the region of interest according to the magnetic field distribution of the main magnetic field obtained in advance and the magnetic field offset corresponding to the region of interest; performing shimming calculation on the intermediate magnetic field distribution of the region of interest to obtain a target magnetic field distribution of the region of interest; determining the first adjustment parameter according to the target magnetic field distribution of the region of interest.

3. The method of claim 1, wherein, The determination of the second adjustment parameter corresponding to the signal suppression region according to the magnetic field offset corresponding to the signal suppression region comprises: determining an intermediate magnetic field distribution corresponding to the signal suppression region according to the magnetic field distribution of the main magnetic field obtained in advance and the magnetic field offset corresponding to the signal suppression region; performing shimming calculation on the intermediate magnetic field distribution of the signal suppression region to obtain a target magnetic field distribution of the signal suppression region; determining the second adjustment parameter according to the target magnetic field distribution of the signal suppression region.

4. The method of claim 1, wherein, The generation of the target magnetic field according to the first adjustment parameter and / or the second adjustment parameter comprises: correcting the magnetic field intensity or uniformity of the region of interest according to the first adjustment parameter to adjust the magnetic field distribution of the region of interest; correcting the magnetic field intensity or uniformity of the signal suppression region according to the second adjustment parameter to adjust the magnetic field distribution of the signal suppression region.

5. The method of claim 1, wherein, The determination of the region of interest and the signal suppression region of the target object comprises: obtaining an initial magnetic resonance image of the target object; performing image recognition on the initial magnetic resonance image to obtain the region of interest and the signal suppression region in the initial magnetic resonance image.

6. The method of claim 1, wherein, The signal suppression region comprises a fat region, and the signal to be suppressed comprises a fat signal, and the method further comprises: suppressing the fat signal by using a preset fat suppression method to obtain a target magnetic resonance signal; performing image reconstruction according to the target magnetic resonance signal to obtain a target magnetic resonance image.

7. A magnetic resonance imaging apparatus, characterized by The device comprises: The region determination module is configured to determine a region of interest and a signal suppression region of the target object. The adjustment parameter determination module is configured to determine a first adjustment parameter corresponding to the region of interest or a second adjustment parameter corresponding to the signal suppression region, the first adjustment parameter and / or the second adjustment parameter being used to adjust a magnetic field distribution of the region of interest to produce a set difference relative to the signal suppression region. The magnetic field generation module is configured to generate a target magnetic field according to the first adjustment parameter and / or the second adjustment parameter. The adjustment parameter determination module includes: The frequency acquisition submodule is configured to acquire an initial center frequency and a target center frequency of each region for the region of interest or the signal suppression region. The magnetic field offset determination submodule is configured to determine a magnetic field offset required to move the initial center frequency to the target center frequency according to a pre-established correlation between the magnetic field and the frequency. The first parameter determination submodule is configured to determine the first adjustment parameter corresponding to the region of interest according to the magnetic field offset corresponding to the region of interest; and / or The second parameter determination submodule is configured to determine the second adjustment parameter corresponding to the signal suppression region according to the magnetic field offset corresponding to the signal suppression region.

8. A magnetic resonance imaging method characterized by, The method includes: Determining a region of interest of a target object; Determining a magnetic field adjustment parameter to produce a set difference in a magnetic field distribution of the region of interest relative to a magnetic field distribution of a signal suppression region; Applying the magnetic field adjustment parameter to generate a target magnetic field; and Applying an imaging sequence under the target magnetic field to acquire a magnetic resonance image of the target object; The determination of the magnetic field adjustment parameter includes: Acquiring an initial center frequency and a target center frequency of each region for the region of interest or the signal suppression region. Determining a magnetic field offset required to move the initial center frequency to the target center frequency according to a pre-established correlation between the magnetic field and the frequency. Determining the first adjustment parameter corresponding to the region of interest according to the magnetic field offset corresponding to the region of interest; and / or Determining the second adjustment parameter corresponding to the signal suppression region according to the magnetic field offset corresponding to the signal suppression region.

9. The method of claim 8, wherein, The magnetic field adjustment parameter is used to adjust a magnetic field uniformity of the region of interest or the signal suppression region; or The magnetic field adjustment parameter is used to adjust a magnetic field offset of the region of interest relative to the signal suppression region.

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