Gradient amplitude correction method, device, equipment, storage medium and program product

Abstract

The application relates to a gradient amplitude correction method and device, equipment, a storage medium and a program product. The method comprises the following steps: acquiring a difference value between a real value and a set value of a diffusion sensitivity factor in a nuclear magnetic resonance equipment imaging process, and determining the difference value as an error value of the diffusion sensitivity factor; determining a correction value of a gradient amplitude according to the error value of the diffusion sensitivity factor; correcting an initial gradient amplitude according to the correction value of the gradient amplitude to obtain a target gradient amplitude; and the target gradient amplitude is used for nuclear magnetic resonance imaging. The method can improve the imaging precision.

Description

Technical Field

[0001] This application relates to the field of medical imaging technology, and in particular to a gradient amplitude correction method, apparatus, device, storage medium, and program product. Background Technology

[0002] With the development of medical technology, nuclear magnetic resonance imaging (NMRI) is also developing rapidly. During the NMRI imaging process, different images can be obtained by setting different diffusion sensitivity factors.

[0003] In related technologies, during the imaging process of nuclear magnetic resonance (NMR) equipment, the diffusion sensitivity factor of the NMR image object can be set according to experience based on the required NMR image, and the NMR image can be obtained according to the set diffusion sensitivity factor.

[0004] However, the methods of these technologies suffer from low imaging accuracy. Summary of the Invention

[0005] Therefore, it is necessary to provide a gradient amplitude correction method, apparatus, device, storage medium, and program product to address the aforementioned technical problems and improve imaging accuracy.

[0006] Firstly, this application provides a gradient magnitude correction method, which includes:

[0007] Obtain the error value of the diffusion sensitive factor during the imaging process of the nuclear magnetic resonance equipment; the error value is the difference between the true value and the set value of the diffusion sensitive factor.

[0008] Determine the correction value of the gradient magnitude based on the error value of the diffusion sensitivity factor;

[0009] The initial gradient magnitude is corrected based on the correction value of the gradient magnitude to obtain the target gradient magnitude; the target gradient magnitude is used for magnetic resonance imaging.

[0010] In one embodiment, obtaining the error value of the diffusion sensitivity factor during magnetic resonance imaging includes:

[0011] Based on the set value of the diffusion sensitivity factor, the initial gradient amplitude during the imaging process of the nuclear magnetic resonance imaging device is obtained;

[0012] Determine the true value of the diffusion sensitivity factor based on the initial gradient magnitude;

[0013] The difference between the true value and the set value of the diffusion sensitivity factor is defined as the error value of the diffusion sensitivity factor.

[0014] In one embodiment, determining the true value of the diffusion sensitivity factor based on the initial gradient magnitude includes:

[0015] Based on the initial gradient magnitude, obtain the true value of the diffusion sensitivity factor for each gradient application time period;

[0016] The true value of the diffusion sensitivity factor is determined based on its true value during each gradient application time period.

[0017] In one embodiment, the true value of the diffusion sensitivity factor is obtained for each gradient application time period based on the initial gradient magnitude, including:

[0018] For the current gradient application time period, the true value of the diffusion sensitivity factor for the current gradient application time period is calculated based on the gyromagnetic ratio, the duration of the current gradient application time period, the gradient magnitude of the current gradient application time period, the duration of the historical gradient application time periods, and the gradient magnitude of the historical gradient application time periods. The historical time periods include all gradient application time periods before the current gradient application time period within the gradient application cycle.

[0019] In one embodiment, the initial gradient magnitude includes at least one of a diffuse gradient magnitude, a layer-selective gradient magnitude, a destructive gradient magnitude, and a preset phase gradient magnitude.

[0020] In one embodiment, determining a correction value for the gradient magnitude based on the error value of the diffusion sensitivity factor includes:

[0021] The correction value of the gradient magnitude is determined based on the correspondence between the error value of the diffusion sensitivity factor and the correction value of the gradient magnitude, as well as the error value of the diffusion sensitivity factor; the correspondence is determined based on the calculation method of the true value of the diffusion sensitivity factor and the calculation method of the initial gradient magnitude.

[0022] Secondly, this application also provides a gradient magnitude correction device, which includes:

[0023] The acquisition module is used to acquire the error value of the diffusion sensitive factor during the imaging process of the nuclear magnetic resonance equipment; the error value is the difference between the true value and the set value of the diffusion sensitive factor.

[0024] The determination module is used to determine the correction value of the gradient magnitude based on the error value of the diffusion sensitivity factor;

[0025] The correction module is used to correct the initial gradient magnitude based on the correction value of the gradient magnitude to obtain the target gradient magnitude; the target gradient magnitude is used for nuclear magnetic resonance imaging.

[0026] Thirdly, this application also provides a computer device. The computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement any one of the gradient magnitude correction methods described in the first aspect above.

[0027] Fourthly, this application also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program thereon, which, when executed by a processor, implements any one of the gradient magnitude correction methods described in the first aspect above.

[0028] Fifthly, this application also provides a computer program product. The computer program product includes a computer program that, when executed by a processor, implements any one of the gradient magnitude correction methods described in the first aspect above.

[0029] The aforementioned gradient amplitude correction method, apparatus, device, storage medium, and program product acquire the error value of the diffusion-sensitive factor during the imaging process of an MRI machine; determine the correction value of the gradient amplitude based on the error value of the diffusion-sensitive factor; and correct the initial gradient amplitude based on the correction value to obtain the target gradient amplitude, which is then used for MRI imaging. This method accurately obtains the error value of the diffusion-sensitive factor by measuring the difference between the true value and the set value. Therefore, a more accurate correction value for the gradient amplitude can be obtained based on the error value of the diffusion-sensitive factor. After correcting the initial gradient amplitude with the correction value, the obtained target gradient amplitude is closer to the gradient amplitude corresponding to the set value. The error between the image obtained by MRI and the image corresponding to the set value is smaller, thereby improving the accuracy of MRI imaging. Attached Figure Description

[0030] Figure 1 This is a diagram illustrating the application environment of the gradient magnitude correction method in one embodiment;

[0031] Figure 2 This is a flowchart illustrating a gradient magnitude correction method in one embodiment;

[0032] Figure 3 This is a flowchart illustrating a gradient magnitude correction method in one embodiment;

[0033] Figure 4 This is a flowchart illustrating a gradient magnitude correction method in one embodiment;

[0034] Figure 5 This is a schematic diagram of diffusion motion in one embodiment;

[0035] Figure 6 This is a flowchart illustrating a gradient magnitude correction method in one embodiment;

[0036] Figure 7 This is a structural block diagram of a gradient magnitude correction device in one embodiment. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0038] Before introducing the embodiments of the gradient magnitude correction method of this application, the background of this application will be introduced first.

[0039] In magnetic resonance imaging (MRI), different images can be obtained by setting different diffusion sensitivity factors. Therefore, before MRI, it is necessary to set the diffusion sensitivity factor corresponding to the target image in order to obtain the MRI image corresponding to that diffusion sensitivity factor. However, during the imaging process of the MRI equipment, there are various interferences that cause a large difference between the actual diffusion sensitivity factor and the set diffusion sensitivity factor, resulting in a large error in the obtained MRI image.

[0040] In related technologies, during the imaging process of nuclear magnetic resonance (NMR) equipment, the diffusion gradient amplitude during the actual imaging process can be determined based on a set diffusion sensitivity factor. When there are no other gradients between the diffusion gradients, or when the amplitudes of other gradients are small, this method can ensure that the deviation between the true value and the set value of the diffusion sensitivity factor is small. However, when there are other gradients between the diffusion gradients, and the diffusion gradient amplitude is large, calculating the diffusion gradient amplitude during the actual imaging process using this method will lead to a large deviation between the true value and the set value of the diffusion sensitivity factor. These other gradients can be slice selection gradients, destruction gradients, and preset phase gradients, etc. Furthermore, after calculating the diffusion gradient amplitude during the actual imaging process using this method, no correction is made to the actual diffusion gradient amplitude; therefore, the accuracy of the NMR image obtained by this method is low.

[0041] Therefore, in order to improve the accuracy of nuclear magnetic resonance imaging, this application provides a gradient magnitude correction method, which will be described below.

[0042] The gradient magnitude correction method provided in this application embodiment can be applied to, for example... Figure 1The application environment is shown. The server's internal structure includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system, computer programs, and a database; the internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The database is used to store data during the gradient magnitude correction process. The network interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements the gradient magnitude correction method provided in this application.

[0043] In one embodiment, such as Figure 2 As shown, a gradient magnitude correction method is provided, which is applied to... Figure 1 Taking the server in the example, the following steps are included:

[0044] S201, Obtain the error value of the diffusion sensitive factor during the imaging process of the nuclear magnetic resonance equipment; the error value is the difference between the true value and the set value of the diffusion sensitive factor.

[0045] The diffusion sensitivity factor refers to the sensitivity of a strong bipolar diffusion-sensitive gradient pulse sequence to diffusion motion during MRI imaging. Different diffusion sensitivity factors correspond to different MRI images; the higher the value of the diffusion sensitivity factor, the greater the diffusion weight of the MRI image, and the greater the contrast between lesions and normal tissues in the MRI image.

[0046] In this embodiment, for the MRI equipment, before performing MRI imaging, a set value for the diffusion sensitivity factor is input. During the MRI imaging process, the diffusion sensitivity factor corresponds to a true value. There may be an error between the set value and the true value. The error between the MRI image corresponding to the true value of the diffusion sensitivity factor and the MRI image corresponding to the set value of the diffusion sensitivity factor is large. Therefore, it is necessary to correct the gradient amplitude to achieve the purpose of correcting the MRI image.

[0047] Before MRI imaging, the server can determine the set value of the diffusion sensitivity factor based on the required MRI image and the correspondence between the MRI image and the diffusion sensitivity factor. Alternatively, the server can use historical diffusion sensitivity factor set values ​​as the set value. During MRI imaging, the server can calculate the true value of the diffusion sensitivity factor based on the gradient amplitude applied during the imaging process. The server calculates the difference between the true value and the set value of the diffusion sensitivity factor and defines this difference as the error value of the diffusion sensitivity factor.

[0048] S202, determine the correction value of the gradient magnitude based on the error value of the diffusion sensitivity factor.

[0049] The gradient magnitude is a unit used to measure the magnitude of the magnetic field gradient during nuclear magnetic resonance imaging.

[0050] Optionally, there is a certain correspondence between the error value of the diffusion-sensitive factor and the correction value of the gradient magnitude. The server can determine the correction value of the gradient magnitude based on the error value of the diffusion-sensitive factor calculated above and the correspondence between the error value of the diffusion-sensitive factor and the correction value of the gradient magnitude. Optionally, the server can train the neural network model based on a large number of historical error values ​​of sensitive factors and correction values ​​of gradient magnitude to obtain a gradient magnitude correction model. The server inputs the error value of the diffusion-sensitive factor into the trained gradient magnitude correction model, analyzes the error value of the diffusion-sensitive factor through the gradient magnitude correction model, and outputs the correction value of the gradient magnitude.

[0051] S203, the initial gradient magnitude is corrected according to the correction value of the gradient magnitude to obtain the target gradient magnitude; the target gradient magnitude is used for nuclear magnetic resonance imaging.

[0052] Optionally, the initial gradient magnitude may include diffuse gradient magnitude, layer selection gradient magnitude, damage gradient magnitude, and preset phase gradient magnitude, etc.

[0053] In this embodiment, the server can simultaneously correct each initial gradient magnitude based on the correction value of the gradient magnitude, or the server can sequentially correct each initial gradient magnitude based on the correction value of the gradient magnitude to convert the initial gradient magnitude into the target gradient magnitude. Based on the target gradient magnitude, the corrected MRI image is determined. The error between the corrected MRI image and the MRI image corresponding to the set value is small.

[0054] In the aforementioned gradient amplitude correction method, the error value of the diffusion-sensitive factor during the imaging process of the MRI equipment is obtained; based on the error value of the diffusion-sensitive factor, the correction value of the gradient amplitude is determined; and the initial gradient amplitude is corrected based on the correction value of the gradient amplitude to obtain the target gradient amplitude. This method can accurately obtain the error value of the diffusion-sensitive factor by measuring the difference between the true value and the set value. Therefore, a more accurate correction value of the gradient amplitude can be obtained based on the error value of the diffusion-sensitive factor. After correcting the initial gradient amplitude with the correction value of the gradient amplitude, the obtained target gradient amplitude is closer to the gradient amplitude corresponding to the set value. The error between the image obtained by MRI and the image corresponding to the set value is smaller, thereby improving the accuracy of MRI.

[0055] Based on the above embodiments, this embodiment is... Figure 2The relevant content of step S201, "Obtaining the error value of the diffusion sensitivity factor during the magnetic resonance imaging process," will be introduced and explained. For example... Figure 3 As shown, step S201 above may include the following:

[0056] S301, based on the set value of the diffusion sensitivity factor, obtains the initial gradient amplitude during the imaging process of the nuclear magnetic resonance equipment.

[0057] Before imaging with an MRI machine, the set value of the diffusion sensitivity factor is input into the MRI machine. During the imaging process, the server can obtain the initial gradient amplitude during the imaging process.

[0058] In this embodiment, the server can train the initial neural network model based on a large number of historical diffusion-sensitive factor settings and historical initial gradient amplitudes to obtain a preset neural network model. The server inputs the settings of the diffusion-sensitive factors into the preset neural network model, analyzes the settings of the diffusion-sensitive factors through the preset neural network model, and outputs the initial gradient amplitude during the imaging process of the nuclear magnetic resonance device.

[0059] S302, determine the true value of the diffusion sensitivity factor based on the initial gradient magnitude.

[0060] In this embodiment, since the initial gradient amplitude is the gradient amplitude during the imaging process of the MRI equipment, and the MRI imaging process corresponds to the actual diffusion sensitivity factor, the initial gradient amplitude is the initial gradient amplitude corresponding to the actual diffusion sensitivity factor. The server can determine the true value of the diffusion sensitivity factor based on the initial gradient amplitude and the correspondence between the initial gradient amplitude and the actual diffusion sensitivity factor.

[0061] S303, the difference between the true value and the set value of the diffusion sensitive factor is determined as the error value of the diffusion sensitive factor.

[0062] In this embodiment, the server can obtain the difference between the true value and the set value of multiple diffusion sensitive factors, calculate the average or weighted average of the multiple differences, and determine the average or weighted average of the multiple differences as the error value of the diffusion sensitive factor.

[0063] In the above gradient amplitude correction method, the initial gradient amplitude during the imaging process of the nuclear magnetic resonance device can be obtained according to the set value of the diffusion sensitive factor. The initial gradient amplitude is the gradient amplitude corresponding to the true value of the diffusion sensitive factor. Thus, the true value of the diffusion sensitive factor can be accurately obtained according to the initial gradient amplitude, and the difference between the true value of the diffusion sensitive factor and the set value is determined as the error value of the diffusion sensitive factor, making the obtained error value of the diffusion sensitive factor more accurate.

[0064] Based on the above embodiments, this embodiment is... Figure 3 The relevant content of step S302, "Determine the true value of the diffusion sensitivity factor based on the initial gradient magnitude," will be introduced and explained. Figure 4 As shown, step S302 above may include the following:

[0065] S401: Based on the initial gradient magnitude, obtain the true value of the diffusion sensitivity factor for each gradient application time period.

[0066] In this embodiment, when different types of initial gradient magnitudes are applied in different gradient application time periods, for each gradient application time period, the server can determine the true value of the diffusion sensitivity factor in each gradient application time period based on the initial gradient magnitude corresponding to that gradient application time period and the correspondence between the initial gradient magnitude and the true value of the diffusion sensitivity factor.

[0067] Each gradient application time period can apply one or more gradient magnitudes. In this embodiment, taking each gradient application time period as one gradient magnitude as an example, Figure 5 This diagram illustrates the diffusion process. Figure 5 The algorithm only involves diffusion gradient and layer selection gradient. During gradient application time periods t1 and t4, diffusion gradient is applied, and the true values ​​of diffusion sensitivity factor during diffusion gradient application time periods t1 and t4 are b1 and b4, respectively. During gradient application time periods t2 and t3, layer selection gradient is applied, and the true values ​​of diffusion sensitivity factor during layer selection gradient application time periods t2 and t3 are b2 and b3, respectively.

[0068] S402, determine the true value of the diffusion sensitivity factor based on the true value of the diffusion sensitivity factor during each gradient application time period.

[0069] In this embodiment, the true value of the diffusion sensitivity factor is the sum of the true values ​​for each gradient application time period. The server can calculate the sum of the true values ​​of the diffusion sensitivity factor for each gradient application time period and determine the calculated result as the true value of the diffusion sensitivity factor.

[0070] In the aforementioned gradient magnitude correction method, the true value of the diffusion sensitivity factor is obtained based on the initial gradient magnitude during each gradient application time period. Then, the true value of the diffusion sensitivity factor is determined based on the true value of the diffusion sensitivity factor during each gradient application time period. This method divides the diffusion sensitivity factor by gradient application time periods, and by using the true value of each gradient application time period, a more accurate true value of the diffusion sensitivity factor can be obtained.

[0071] Based on the above embodiments, this embodiment is... Figure 4The following describes step S401, "Obtaining the true value of the diffusion sensitivity factor for each gradient application time period based on the initial gradient magnitude." Step S401 may include the following: For the current gradient application time period, the true value of the diffusion sensitivity factor for the current gradient application time period is calculated based on the gyromagnetic ratio, the duration of the current gradient application time period, the gradient magnitude of the current gradient application time period, the duration of historical gradient application time periods, and the gradient magnitude of historical gradient application time periods; the historical time periods include all gradient application time periods prior to the current gradient application time period within the gradient application cycle.

[0072] The gyromagnetic ratio represents the ratio of the angular frequency of an atom undergoing Larmor precession in a magnetic field to the intensity of the magnetic induction.

[0073] In this embodiment, it is still based on Figure 5 For example, if the application time periods of the two diffusion gradients are equal, then the application time periods of both diffusion gradients are denoted by t. g This is indicated by the expression t. Simultaneously, the time interval for applying the layer selection gradient before and after the re-convergence pulse is the same. Both the time intervals for applying the layer selection gradient before and after the re-convergence pulse are denoted by t. s express.

[0074] If the duration of the current gradient application period is t1, and the gradient magnitude of the current gradient application period is G when a diffuse gradient is applied, the true value b1 of the diffuse sensitivity factor for the current gradient application period t1 can be expressed as:

[0075]

[0076] If the duration of the current gradient application period is t2, and the gradient magnitude of the current gradient application period is H when applying the layer selection gradient, the true value b2 of the diffusion sensitivity factor for the current gradient application period t2 can be expressed as:

[0077]

[0078] Where K1=γt g G, the true value b2 of the diffusion sensitivity factor during the current gradient application time period t2 can be expressed as:

[0079]

[0080] If the duration of the current gradient application period is t3, and the gradient magnitude of the current gradient application period is H when applying the layer selection gradient, the true value of the diffusion sensitivity factor b3 for the current gradient application period t3 can be expressed as:

[0081]

[0082] Among them, K 12 =γt g G+γt s H, the true value b3 of the diffusion sensitivity factor during the current gradient application time period t3 can be expressed as:

[0083]

[0084] If the duration of the current gradient application period is t4, and the gradient magnitude during the current gradient application period is G, then the true value b4 of the diffusion sensitivity factor during the current gradient application period t4 can be expressed as:

[0085]

[0086] Among them, K 123 =K1=γt g G, the true value b4 of the diffusion sensitivity factor during the current gradient application time period t4 can be expressed as:

[0087]

[0088] In the aforementioned gradient magnitude correction method, for the current gradient application period, the true value of the diffusion sensitivity factor is calculated based on the gyromagnetic ratio, the duration of the current gradient application period, the gradient magnitude of the current gradient application period, the duration of historical gradient application periods, and the gradient magnitude of historical gradient application periods. The historical periods include all gradient application periods prior to the current gradient application period within the gradient application cycle. This method, in calculating the true value of the diffusion sensitivity factor for the current gradient application period, considers not only the duration and gradient magnitude of the current gradient application period but also the duration and gradient magnitude of historical gradient application periods, making the obtained true value of the diffusion sensitivity factor for the current gradient application period more accurate.

[0089] Based on the above embodiments, this embodiment is... Figure 2 The following describes step S202, "Determining the correction value of the gradient magnitude based on the error value of the diffusion sensitive factor." Step S202 may include the following: determining the correction value of the gradient magnitude based on the correspondence between the error value of the diffusion sensitive factor and the error value of the gradient magnitude, and the error value of the diffusion sensitive factor; the correspondence is determined based on the calculation method of the true value of the diffusion sensitive factor and the calculation method of the initial gradient magnitude.

[0090] In this embodiment, there is a correspondence between the error value of the diffusion sensitive factor and the correction value of the gradient magnitude. The server can determine the correspondence between the error value of the diffusion sensitive factor and the correction value of the gradient magnitude based on the calculation formula of the true value of the diffusion sensitive factor. Therefore, based on this correspondence and the error value of the diffusion sensitive factor, the correction value of the gradient magnitude can be determined. The following describes the process of obtaining the error value of the diffusion sensitive factor and the error value of the gradient magnitude based on the calculation method of the true value of the diffusion sensitive factor and the calculation method of the initial gradient magnitude. Figure 5 For example, the true value of the diffusion sensitivity factor can be expressed as:

[0091]

[0092] Assumption The true value of the diffusion sensitivity factor can then be expressed as:

[0093] b = AG 2 +BG+C

[0094] According to the method for solving quadratic functions, we can obtain:

[0095]

[0096] from Figure 5 As can be seen from this, G is a positive value, therefore

[0097] Taking the derivative of the true value b of the diffusion effect factor, we get:

[0098]

[0099] Therefore, the relationship between the error value of the dispersion influence factor and the correction value of the gradient magnitude can be expressed as:

[0100]

[0101] In the aforementioned gradient magnitude correction method, the correction value of the gradient magnitude is determined based on the correspondence between the error value of the diffusion sensitive factor and the correction value of the gradient magnitude, as well as the error value of the diffusion sensitive factor. This method, through the calculation methods of the true value of the diffusion sensitive factor and the initial gradient magnitude, can obtain a more accurate correspondence between the error value of the diffusion sensitive factor and the correction value of the gradient magnitude, thus making the obtained correction value of the gradient magnitude more accurate.

[0102] In one embodiment, the gradient magnitude correction method is described in detail below, such as... Figure 6 As shown, the method may include:

[0103] S501, based on the set value of the diffusion sensitivity factor, obtains the initial gradient amplitude during the imaging process of the nuclear magnetic resonance equipment;

[0104] S502, for the current gradient application time period, calculate the true value of the diffusion sensitivity factor for the current gradient application time period based on the gyromagnetic ratio, the duration of the current gradient application time period, the gradient magnitude of the current gradient application time period, the duration of the historical gradient application time period, and the gradient magnitude of the historical gradient application time period.

[0105] S503, determine the true value of the diffusion sensitivity factor based on the true value of the diffusion sensitivity factor during each gradient application time period;

[0106] S504, Based on the correspondence between the diffusion sensitivity factor and the gradient magnitude, and the error value of the diffusion sensitivity factor, determine the correction value of the gradient magnitude;

[0107] S505, corrects the initial gradient magnitude based on the correction value of the gradient magnitude to obtain the target gradient magnitude.

[0108] In the above gradient amplitude correction method, the initial gradient amplitude during the imaging process of the nuclear magnetic resonance equipment is obtained according to the set value of the diffusion sensitivity factor. For the current gradient application time period, the true value of the diffusion sensitivity factor for the current gradient application time period is calculated based on the gyromagnetic ratio, the duration of the current gradient application time period, the gradient amplitude of the current gradient application time period, the duration of the historical gradient application time period, and the gradient amplitude of the historical gradient application time period. Based on the true value of the diffusion sensitivity factor in each gradient application time period, the true value of the diffusion sensitivity factor is determined. Based on the correspondence between the diffusion sensitivity factor and the gradient amplitude, and the error value of the diffusion sensitivity factor, the correction value of the gradient amplitude is determined. The initial gradient amplitude is corrected based on the correction value of the gradient amplitude to obtain the target gradient amplitude. This method can accurately obtain the error value of the diffusion sensitive factor by measuring the difference between the true value and the set value. Based on the error value of the diffusion sensitive factor, a more accurate correction value for the gradient amplitude can be obtained. After correcting the initial gradient amplitude with the correction value, the target gradient amplitude obtained is closer to the gradient amplitude corresponding to the set value. The error between the image obtained by MRI and the image corresponding to the set value is smaller, thereby improving the accuracy of MRI.

[0109] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0110] Based on the same inventive concept, this application also provides a gradient magnitude correction device for implementing the gradient magnitude correction method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations in one or more gradient magnitude correction device embodiments provided below can be found in the limitations of the gradient magnitude correction method described above, and will not be repeated here.

[0111] In one embodiment, such as Figure 7 As shown, a gradient magnitude correction device is provided, comprising: an acquisition module 11, a determination module 12, and a correction module 13, wherein:

[0112] The acquisition module is used to acquire the error value of the diffusion sensitive factor during the imaging process of the nuclear magnetic resonance equipment; the error value is the difference between the true value and the set value of the diffusion sensitive factor.

[0113] The determination module is used to determine the correction value of the gradient magnitude based on the error value of the diffusion sensitivity factor;

[0114] The correction module is used to correct the initial gradient magnitude based on the correction value of the gradient magnitude to obtain the target gradient magnitude; the target gradient magnitude is used for nuclear magnetic resonance imaging.

[0115] Optionally, the initial gradient magnitude includes at least one of the following: diffuse gradient magnitude, layer selection gradient magnitude, damage gradient magnitude, and preset phase gradient magnitude.

[0116] In one embodiment, the above-mentioned acquisition module includes: an acquisition unit, a first determination unit, and a second determination unit, wherein:

[0117] The acquisition unit is used to acquire the initial gradient amplitude during the imaging process of the nuclear magnetic resonance device according to the set value of the diffusion sensitivity factor;

[0118] The first determining unit is used to determine the true value of the diffusion sensitivity factor based on the initial gradient magnitude.

[0119] The second determining unit is used to determine the difference between the true value and the set value of the diffusion sensitive factor as the error value of the diffusion sensitive factor.

[0120] In one embodiment, the first determining unit is further configured to obtain the true value of the diffusion sensitive factor for each gradient application time period based on the initial gradient magnitude; and to determine the true value of the diffusion sensitive factor based on the true value of the diffusion sensitive factor for each gradient application time period.

[0121] In one embodiment, the first determining unit is further configured to calculate the true value of the diffusion sensitivity factor for the current gradient application time period based on the gyromagnetic ratio, the duration of the current gradient application time period, the gradient magnitude of the current gradient application time period, the duration of the historical gradient application time period, and the gradient magnitude of the historical gradient application time period; the historical time period includes all gradient application time periods prior to the current gradient application time period within the gradient application cycle.

[0122] In one embodiment, the determining module includes a third determining unit, wherein:

[0123] The third determining unit is used to determine the correction value of the gradient magnitude based on the correspondence between the error value of the diffusion sensitive factor and the correction value of the gradient magnitude, as well as the error value of the diffusion sensitive factor; the correspondence is determined based on the calculation method of the true value of the diffusion sensitive factor and the calculation method of the initial gradient magnitude.

[0124] Each module in the aforementioned gradient magnitude correction device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the corresponding operations of each module.

[0125] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the content of any of the method embodiments of the first aspect described above.

[0126] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the content of any of the method embodiments of the first aspect described above.

[0127] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the content of any of the method embodiments of the first aspect described above.

[0128] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0129] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this 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, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0130] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0131] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A gradient magnitude correction method, characterized in that, The method includes: Obtain the error value of the diffusion sensitive factor during the imaging process of the nuclear magnetic resonance imaging device; the error value is the difference between the true value and the set value of the diffusion sensitive factor; The correction value of the gradient magnitude is determined based on the correspondence between the error value of the diffusion sensitive factor and the correction value of the gradient magnitude, and the error value of the diffusion sensitive factor; the correspondence is determined based on the calculation method of the true value of the diffusion sensitive factor and the calculation method of the initial gradient magnitude. The initial gradient magnitude is corrected according to the correction value of the gradient magnitude to obtain the target gradient magnitude; the target gradient magnitude is used for nuclear magnetic resonance imaging.

2. The method according to claim 1, characterized in that, The error value of the diffusion sensitivity factor obtained during the imaging process of the nuclear magnetic resonance imaging device includes: Based on the set value of the diffusion sensitivity factor, the initial gradient amplitude during the imaging process of the nuclear magnetic resonance device is obtained; Based on the initial gradient magnitude, determine the true value of the diffusion sensitivity factor; The difference between the true value of the diffusion sensitivity factor and the set value is determined as the error value of the diffusion sensitivity factor.

3. The method according to claim 2, characterized in that, Determining the true value of the diffusion sensitivity factor based on the initial gradient magnitude includes: Based on the initial gradient magnitude, obtain the true value of the diffusion sensitivity factor for each gradient application time period; The true value of the diffusion sensitivity factor is determined based on its true value during each gradient application time period.

4. The method according to claim 3, characterized in that, The step of obtaining the true value of the diffusion sensitivity factor for each gradient application time period based on the initial gradient magnitude includes: For the current gradient application time period, the true value of the diffusion sensitivity factor for the current gradient application time period is calculated based on the gyromagnetic ratio, the duration of the current gradient application time period, the gradient magnitude of the current gradient application time period, the duration of historical gradient application time periods, and the gradient magnitude of historical gradient application time periods; the historical gradient application time periods include all gradient application time periods prior to the current gradient application time period within the gradient application cycle.

5. The method according to any one of claims 1-4, characterized in that, The initial gradient magnitude includes at least one of the following: diffuse gradient magnitude, layer selection gradient magnitude, damage gradient magnitude, and preset phase gradient magnitude.

6. The method according to any one of claims 1-4, characterized in that, The gradient magnitude represents a unit for measuring the magnitude of the magnetic field gradient during the imaging process of a nuclear magnetic resonance imaging (NMR) device.

7. A gradient magnitude correction device, characterized in that, The device includes: An acquisition module is used to acquire the error value of the diffusion sensitive factor during the imaging process of the nuclear magnetic resonance equipment; the error value is the difference between the true value and the set value of the diffusion sensitive factor; The determining module is used to determine the correction value of the gradient magnitude based on the correspondence between the error value of the diffusion sensitive factor and the correction value of the gradient magnitude, and the error value of the diffusion sensitive factor; the correspondence is determined based on the calculation method of the true value of the diffusion sensitive factor and the calculation method of the initial gradient magnitude. The correction module is used to correct the initial gradient magnitude according to the correction value of the gradient magnitude to obtain the target gradient magnitude; the target gradient magnitude is used for nuclear magnetic resonance imaging.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

Images