Method and device for correcting magnetic resonance image, computer device and storage medium

Abstract

The application relates to a magnetic resonance image correction method and device, computer equipment and a storage medium. The method comprises the following steps: obtaining initial coordinates of each pixel point in an original image of a magnetic resonance scan; determining a vortex distortion function according to gradient vortex configuration information and protocol information; determining spatial offsets of each pixel point according to the vortex distortion function and the initial coordinates of each pixel point, wherein the spatial offsets are generated by vortex field deformation; correcting the initial coordinates of each pixel point in the original image based on the spatial offsets to obtain corrected coordinates of each pixel point; and obtaining a corrected target image according to the corrected coordinates of each pixel point. In the method, the computer equipment determines the spatial offsets of each pixel point according to the gradient vortex configuration information, the protocol information and the initial coordinates of each pixel point, and the coordinates of the pixel points are corrected based on an algorithm, so that an additional hardware vortex compensation module is not needed, vortex compensation is realized, and the cost of vortex compensation is reduced.

Description

Technical Field

[0001] This application relates to the field of magnetic resonance imaging technology, and in particular to a method, apparatus, computer device, and storage medium for correcting magnetic resonance images. Background Technology

[0002] Diffusion imaging (DIM) is one of the fastest magnetic resonance imaging (MRI) techniques available today. It can be used to study the thermal motion of molecules within biological tissues and is widely used in clinical diagnosis and scientific research. The DIM process uses multiple diffusion gradients in different directions to obtain diffusion images in different orientations. However, the diffusion gradients generate eddy fields as they rise and fall. These eddy fields persist during the encoding process, causing distortion in the diffusion images in different orientations. Because the distortion of diffusion images varies significantly across different orientations, synthesizing a diffusion-weighted image from these images can lead to image blurring or even artifacts.

[0003] To avoid or correct the deformation of the eddy current field caused by the diffusion gradient, existing technologies add a hardware eddy current compensation module to the device that acquires the initial sequence, and then use the eddy current compensation module to correct the initial sequence to obtain a corrected sequence, thereby obtaining a diffusion image based on the corrected sequence.

[0004] However, the above method requires the addition of a hardware eddy current compensation module on the device side to modify the existing sequence design, resulting in relatively high hardware costs. Summary of the Invention

[0005] Therefore, it is necessary to provide a method, apparatus, computer equipment, and storage medium for correcting magnetic resonance images that can achieve low-cost eddy current compensation, addressing the aforementioned technical problems.

[0006] Firstly, a method for correcting magnetic resonance images is provided, the method comprising:

[0007] Obtain the initial coordinates of each pixel in the original image of the magnetic resonance scan;

[0008] The eddy current distortion function is determined based on the gradient eddy current configuration information and protocol information;

[0009] Based on the eddy current distortion function and the initial coordinates of each pixel, the spatial offset of each pixel is determined. The spatial offset is generated by the deformation of the eddy current field.

[0010] The initial coordinates of each pixel in the original image are corrected based on spatial offset to obtain the corrected coordinates of each pixel; and the corrected target image is obtained based on the corrected coordinates of each pixel.

[0011] In one embodiment, the protocol information includes the time interval between the eddy current field generated by the pixel's diffusion gradient rising and falling in various directions and reaching the center point of the k-space.

[0012] In one embodiment, determining the eddy current distortion function based on the gradient eddy current configuration information and protocol information includes:

[0013] The eddy current field polynomial is determined based on the eddy current configuration file and protocol information;

[0014] The eddy distortion function is determined based on the eddy field polynomial.

[0015] In one embodiment, the eddy current distortion function includes a transverse distortion expression and a longitudinal distortion expression.

[0016] In one embodiment, determining the spatial offset of each pixel based on the eddy current distortion function and the initial coordinates of each pixel includes:

[0017] Transform the initial coordinates of each pixel to obtain the logical coordinates of each pixel;

[0018] Based on the eddy current distortion function, determine the spatial offset corresponding to the logical coordinates of each pixel.

[0019] In one embodiment, the spatial offset corresponding to the logical coordinates of each pixel is obtained in the following way:

[0020] The original image is meshed to obtain the grid coordinates of each pixel in the grid.

[0021] By iterating through the grid coordinates of each pixel and substituting them into the eddy current distortion function, the spatial offset of each pixel is obtained.

[0022] In one embodiment, the target image is determined as follows:

[0023] The calculated pixel value corresponding to the corrected coordinates of each pixel is obtained by interpolation.

[0024] The calculated pixel values ​​are then filled into the initial coordinate positions of each pixel to obtain the target image.

[0025] Secondly, a magnetic resonance image correction device is provided, the device comprising:

[0026] The determination module is used to obtain the initial coordinates of each pixel in the original image of the magnetic resonance scan;

[0027] A module is built to determine the eddy current distortion function based on gradient eddy current configuration information and protocol information;

[0028] The correction module is used to determine the spatial offset of each pixel based on the eddy current distortion function and the initial coordinates of each pixel. The spatial offset is generated by the deformation of the eddy current field. The module also corrects the initial coordinates of each pixel in the original image based on the spatial offset to obtain the corrected coordinates of each pixel.

[0029] The imaging module is used to obtain the corrected target image based on the corrected coordinates of each pixel.

[0030] Thirdly, a computer device is provided, including a memory and a processor, the memory storing a computer program, the processor executing the computer program to implement the magnetic resonance image correction method described in any of the first aspects above.

[0031] Fourthly, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the magnetic resonance image correction method described in any of the first aspects above.

[0032] The aforementioned magnetic resonance image correction method, apparatus, computer equipment, and storage medium involve the computer equipment acquiring the initial coordinates of each pixel in the original magnetic resonance scan image, determining the eddy current distortion function based on gradient eddy current configuration information and protocol information, determining the spatial offset of each pixel based on the eddy current distortion function and the initial coordinates of each pixel (the spatial offset is generated by the deformation of the eddy current field), correcting the initial coordinates of each pixel in the original image based on the spatial offset, obtaining the corrected coordinates of each pixel, and obtaining the corrected target image based on the corrected coordinates of each pixel. In this method, the computer equipment determines the eddy current distortion function based on gradient eddy current configuration information and protocol information, and determines the spatial offset of each pixel based on the eddy current distortion function and the initial coordinates of each pixel, thereby obtaining the corrected coordinates of each pixel based on the spatial offset. The entire process is based on software algorithms to achieve coordinate correction of each pixel, without the need for additional hardware eddy current compensation modules, thus reducing the cost of eddy current compensation while implementing eddy current compensation based on software algorithms. Attached Figure Description

[0033] Figure 1 This is an application environment diagram of a magnetic resonance image correction method in one embodiment;

[0034] Figure 2 This is a flowchart illustrating a magnetic resonance image correction method in one embodiment;

[0035] Figure 3 This is a schematic diagram illustrating the rise and fall of the diffusion gradient in a magnetic resonance image correction method in one embodiment;

[0036] Figure 4 This is a flowchart illustrating a magnetic resonance image correction method in one embodiment;

[0037] Figure 5 This is a flowchart illustrating a magnetic resonance image correction method in one embodiment;

[0038] Figure 6 This is a flowchart illustrating a magnetic resonance image correction method in one embodiment;

[0039] Figure 7 This is a schematic diagram of meshing in a magnetic resonance image correction method in one embodiment;

[0040] Figure 8 This is a flowchart illustrating a magnetic resonance image correction method in one embodiment;

[0041] Figure 9 This is a flowchart illustrating a magnetic resonance image correction method in one embodiment;

[0042] Figure 10 This is a structural block diagram of a magnetic resonance image correction device in one embodiment. Detailed Implementation

[0043] 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.

[0044] The magnetic resonance image correction method provided in this application can be applied to, for example... Figure 1 In the application environment shown, in one embodiment, a computer device is provided, which can be a server or a terminal, and its internal structure diagram can be as follows. Figure 1 As shown, the computer device includes a processor, memory, communication interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, NFC (Near Field Communication), or other technologies. When executed by the processor, the computer program implements a method for correcting magnetic resonance images. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the computer device casing, or an external keyboard, touchpad, or mouse.

[0045] Those skilled in the art will understand that Figure 1 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0046] The technical solutions of this application and how they solve the aforementioned technical problems will be described in detail below through embodiments and in conjunction with the accompanying drawings. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. It should be noted that this application... Figures 2-10 The magnetic resonance image correction method provided in this embodiment is executed by a computer device, or it can be a magnetic resonance image correction device. This magnetic resonance image correction device can be part or all of the computer device through software, hardware, or a combination of both. In the following method embodiments, the execution subject is always described using a computer device as an example.

[0047] In one embodiment, such as Figure 2 As shown, a method for correcting magnetic resonance images is provided. This method involves a computer device determining the initial coordinates of each pixel in the original image based on protocol information; determining the eddy current distortion function based on gradient eddy current configuration information and protocol information; determining the spatial offset of each pixel based on the eddy current distortion function and the initial coordinates of each pixel; correcting the initial coordinates of each pixel in the original image based on the spatial offset to obtain the corrected coordinates of each pixel; and obtaining the corrected target image based on the corrected coordinates of each pixel. The method includes the following steps:

[0048] S201. Obtain the initial coordinates of each pixel in the original image of the magnetic resonance scan.

[0049] In this embodiment, the initial coordinates of each pixel in the original image are obtained based on protocol information, also known as pulse sequence information. This information comprises the settings and temporal arrangement of various parameters related to the radio frequency pulse, gradient field, and / or signal acquisition timing. Parameters related to the radio frequency pulse may include the pulse bandwidth, intensity, application time, and duration. Parameters related to the gradient field may include the gradient field application direction, gradient field strength, application time, and duration. In this embodiment, the gradient field is set as a diffuse gradient field. The protocol information includes one or more combinations of the following: the time interval between the eddy current fields generated by the diffusion gradient rising and falling in various directions reaching the center point of k-space, matrix, layer thickness, interlayer spacing, and field of view. The original image is a magnetic resonance image obtained by applying a diffuse gradient field. In this embodiment, the matrix represents the number of rows and columns within the original image layer of the magnetic resonance scan, i.e., the number of pixels in the frequency encoding and phase encoding directions. The calculated coordinates (theoretical coordinates) of each pixel in the original image can be obtained through the matrix, which is also the initial coordinates of each pixel in the original image.

[0050] Optionally, the computer device can calculate the time interval corresponding to each vortex field by obtaining the first time point of the vortex field generated when the diffusion gradient of the pixel point rises and falls in various directions and the second time point when each vortex field reaches the center point of k space.

[0051] In this embodiment, as Figure 3 As shown, Figure 3 Four time points are given: time points 1 and 4 for the diffusion gradient ascent, and time points 2 and 3 for the diffusion gradient descent. The computer device can determine the time interval between two adjacent phase codes. The second time point Q at which each vortex field reaches the center point of k-space is determined. Based on the first and second time points, four time intervals t1, t2, t3, and t4 can be determined. These time intervals are used as the protocol information for the pixels in the current original image. Furthermore, the computer device can obtain the initial coordinates of each pixel in the original image based on the determined protocol information.

[0052] In this embodiment, the eddy field sensed at the moment of collecting the k-space center point is used as the basis for constructing the eddy field (function) polynomial, thereby constructing a sufficiently accurate eddy field polynomial that is independent of time.

[0053] S202. Determine the eddy current distortion function based on the gradient eddy current configuration information and protocol information.

[0054] In this embodiment, optionally, the computer device can acquire gradient eddy current configuration information of the eddy current field through the system, and then determine the eddy current distortion function based on the protocol information and the gradient eddy current configuration information. Optionally, the eddy current distortion function includes a transverse distortion equation and a longitudinal distortion equation. The computer device can determine the transverse distortion equation of each pixel based on parameters such as the spatial offset of each pixel and a preset sampling time interval. Optionally, the computer device can also determine the longitudinal distortion equation of each pixel based on parameters such as the spatial offset of each pixel and the time interval between two adjacent phase codes.

[0055] S203. Based on the eddy current distortion function and the initial coordinates of each pixel, determine the spatial offset of each pixel. The spatial offset is generated by the deformation of the eddy current field.

[0056] In this embodiment, the computer device substitutes the initial coordinates of each pixel into the eddy current distortion function to calculate the spatial offset of each pixel. It should be noted that the spatial offset calculated based on the eddy current distortion function can represent the degree of deformation of the eddy current field.

[0057] S204. Correct the initial coordinates of each pixel in the original image based on spatial offset to obtain the corrected coordinates of each pixel; and obtain the corrected target image based on the corrected coordinates of each pixel.

[0058] In this embodiment, the computer device determines the correction coordinates of each pixel based on the spatial offset of each pixel, and then obtains the corrected target image based on the correction coordinates of each pixel. Optionally, during the calculation of the spatial offset of each pixel, the computer device can also grid the pixels on the original image, and calculate the correction coordinates of each grid point by traversing the initial coordinates of each point on the grid and substituting the initial coordinates into the eddy current distortion function, thereby determining the target image based on the correction coordinates. Optionally, the computer device can determine the target image based on the pixel values ​​of the correction coordinates; this embodiment does not limit this.

[0059] In the aforementioned magnetic resonance image correction method, the computer device determines the initial coordinates of each pixel in the original image based on protocol information, determines the eddy current distortion function based on gradient eddy current configuration information and protocol information, determines the spatial offset of each pixel based on the eddy current distortion function and the initial coordinates of each pixel (the spatial offset is generated by the deformation of the eddy current field), corrects the initial coordinates of each pixel in the original image based on the spatial offset, and obtains the corrected coordinates of each pixel. The corrected target image is then obtained based on the corrected coordinates of each pixel. In this method, the computer device determines the eddy current distortion function based on gradient eddy current configuration information and protocol information, and determines the spatial offset of each pixel based on the eddy current distortion function and the initial coordinates of each pixel. Thus, the corrected coordinates of each pixel are obtained based on the spatial offset of each pixel. The entire process is based on software algorithms to achieve coordinate correction of each pixel, without the need for additional hardware eddy current compensation modules. This reduces the cost of eddy current compensation while implementing it based on software algorithms.

[0060] When determining the spatial offset of each pixel, the computer device can do so based on the initial coordinates and protocol information of each pixel in the original image. In one embodiment, such as... Figure 4 As shown, the eddy current distortion function is determined based on the gradient eddy current configuration information and protocol information, including:

[0061] S401. Determine the eddy current field polynomial based on the eddy current configuration file and protocol information.

[0062] In this embodiment, the computer device can describe the eddy field using a spherical harmonic expansion based on the characteristics of the eddy field. Optionally, the computer device can construct the eddy field polynomial corresponding to each time interval of each pixel based on the spherical harmonic expansion, according to protocol information, i.e., the time interval between the eddy field generated by the diffusion gradient of each pixel in the original image rising and falling in various directions and reaching the center point of k-space. The eddy field polynomial can be represented by an expansion of no more than order 3 as follows:

[0063]

[0064] in, These are the initial coordinates of the pixel. For a specific time interval of a pixel; This is a function of time t and is related to the diffusion gradient. After the magnetic resonance imaging (MRI) system is deployed, the diffusion gradient eddy current field in each direction will be measured and given. Values ​​at certain points in time (e.g., 2ms, 4ms, 6ms, ..., 200ms) within a certain time range (e.g., 2ms~200ms).

[0065] Table 1 shows a sample table, specifically a table of eddy current coefficients related to the dispersion gradient. The eddy current profile includes this table, where rows represent time points and columns represent coefficients of each order C1~C1. m , where m and n are both integers greater than 1.

[0066] Table 1

[0067]

[0068] S402. Determine the eddy distortion function based on the eddy field polynomial.

[0069] In this embodiment, the computer device obtains the time intervals between the eddy current fields generated by the rising and falling diffusion gradients of each pixel in various directions and their arrival at the center point of the k-space. For each time interval, the device substitutes all the time points within the current time interval and the initial coordinates of each pixel into the eddy current field polynomial corresponding to the current time interval to determine the eddy current distortion function corresponding to each pixel. Optionally, if there are multiple time intervals, after determining the eddy current coefficients and corresponding eddy current polynomials for each time interval, the sum of all eddy current field polynomials can be used as the eddy current distortion function of the original image. Based on the eddy current field polynomials corresponding to each time interval, the eddy current distortion function expression for each pixel of the original image is obtained.

[0070] Optionally, in one embodiment, the eddy current distortion function includes a transverse distortion expression and a longitudinal distortion expression.

[0071] The computer equipment can determine the spatial offset of each pixel based on the eddy current distortion function and the initial coordinates of each pixel. Thus, based on the spatial offset of each pixel Sampling time interval Preset frequency The lateral distortion expression for each pixel is determined as follows:

[0072]

[0073] In addition, computer devices can adjust the spatial offset of each pixel. The time interval between two consecutive phase codes The number of phase points in the phase encoding direction is The vertical distortion expression for each pixel is determined as follows:

[0074]

[0075] In this embodiment, optionally, by using the usual sampling parameter settings, it can be found that... , and Therefore, in actual correction, the deformation in the transverse RO direction can be ignored and only the longitudinal PE direction can be corrected.

[0076] In this embodiment, the computer device constructs an eddy current field expression based on the time interval between the eddy current field generated by the diffusion gradient of each pixel in each direction rising and falling and the center point of the k-space, as well as the eddy current configuration file. This can effectively and accurately determine the spatial offset caused by each pixel when generating the eddy current field. Based on the known parameters, the horizontal distortion expression and vertical distortion expression of each pixel are constructed. This can quickly and effectively determine the distortion of each pixel in the frequency readout (RO) direction or phase encoding (PE) direction, thereby correcting the coordinates of each pixel.

[0077] Optionally, after constructing the eddy current distortion function, in one embodiment, the computer device, such as Figure 5 As shown, the spatial offset of each pixel is determined based on the eddy current distortion function and the initial coordinates of each pixel, including:

[0078] S501. Transform the initial coordinates of each pixel to obtain the logical coordinates of each pixel.

[0079] In this embodiment, the computer device converts the initial coordinates of each pixel in the physical coordinate system to logical coordinates in the logical coordinate system. The conversion between the logical and physical coordinate systems can be achieved through rotation and translation. For example, assuming the rotation matrix is ​​RotA, the coordinates of the logical origin in the physical coordinate system are... Then the coordinate transformation formula can be expressed as:

[0080]

[0081] S502. Based on the eddy current distortion function, determine the spatial offset corresponding to the logical coordinates of each pixel.

[0082] In this embodiment, the computer device substitutes the logical coordinates of each pixel into the eddy current distortion function to obtain the corresponding spatial offset of each pixel.

[0083] In this embodiment, the computer device can effectively determine the spatial offset of each pixel through the eddy current distortion function, thereby determining the correction coordinates of each pixel, and then determining the target image based on the correction coordinates. This implementation method is simple and effective.

[0084] Computer equipment can perform meshing on the original image to obtain the spatial offset corresponding to the logical coordinates of each pixel. In one embodiment, such as... Figure 6 As shown, the spatial offset corresponding to the logical coordinates of each pixel is obtained in the following way:

[0085] S601. Perform gridding on the original image to obtain the grid coordinates of each pixel in the grid.

[0086] In this embodiment, the computer device performs gridding processing on the original image, such as... Figure 7 As shown, Figure 7 A schematic diagram of a 10x10 pixel matrix after meshing is given. Rows represent the RO direction, and columns represent the PE direction. With the grid center as the origin, RO and PE as the coordinate planes, and the layer selection direction SS forming a logical coordinate system according to the right-hand rule. A~D on the grid represent pixels before correction. The computer device uses any traversal algorithm to obtain the grid coordinates of all pixels in the grid. Optionally, the computer device can also store the obtained grid coordinates of each pixel in a specified storage space.

[0087] S602. Substitute the grid coordinates of each pixel into the eddy current distortion function to obtain the spatial offset of each pixel.

[0088] In this embodiment, the computer device iterates through the grid coordinates of each pixel and substitutes them into the eddy current distortion function to calculate the spatial offset of each pixel.

[0089] In this embodiment, the computer device performs gridding processing on the original image, and calculates the spatial offset and distortion coordinates of each pixel based on the grid coordinates of each pixel after gridding processing, which is more accurate.

[0090] After obtaining the correction coordinates, the computer device uses the correction coordinates of each pixel to obtain the corrected target image. In one embodiment, such as... Figure 8 As shown, the target image is determined in the following way:

[0091] S701. The calculated pixel value corresponding to the corrected coordinates of each pixel is obtained by interpolation.

[0092] In this embodiment, optionally, the computer device can determine the calculated pixel value corresponding to the corrected coordinates of each pixel using interpolation.

[0093] In this embodiment, as Figure 7 As shown, assuming that pixel A is deformed to point A' due to the eddy current field, and A' falls between C and D, then the position of point A on the corrected image grid will be filled with the pixel value of A'. The coordinates of A' can be obtained by interpolating the coordinates of points C and D. By traversing all points on the grid, the corrected coordinates of all pixels can be obtained, and their corresponding calculated pixel values ​​can be obtained based on these corrected coordinates.

[0094] S702. Fill the calculated pixel values ​​into the initial coordinate positions of each pixel to obtain the target image.

[0095] In this embodiment, the computer device calculates the pixel value corresponding to the corrected coordinates of each pixel point based on the obtained correction coordinates, and replaces the calculated pixel value at the correction coordinates with the pixel value at the initial coordinates of each pixel point according to the correspondence between the correction coordinates and the initial coordinates of each pixel point. This process refills the pixel values ​​of all pixels, thereby obtaining the corrected image, which is the target image.

[0096] In this embodiment, based on the correspondence between the corrected coordinates and the initial coordinates of each pixel, the calculated pixel values ​​of the corrected coordinates are filled into the initial coordinate positions to complete the correction and compensation of each pixel in the original image. This scheme achieves eddy current compensation without adding a new hardware eddy current compensation module, thus reducing the cost of eddy current compensation.

[0097] To better illustrate the above methods, such as Figure 9 As shown, this embodiment provides a method for correcting magnetic resonance images, specifically including:

[0098] S101. Obtain the initial coordinates of each pixel in the original image;

[0099] S102. Determine the eddy current field polynomial based on the eddy current configuration file and protocol information;

[0100] S103. Determine the eddy current distortion function based on the eddy current field polynomial;

[0101] S104. Transform the initial coordinates of each pixel to obtain the logical coordinates of each pixel;

[0102] S105. Perform gridding on the original image to obtain the grid coordinates of each pixel in the grid.

[0103] S106. Substitute the grid coordinates of each pixel into the eddy current distortion function to obtain the spatial offset of each pixel.

[0104] S107. Correct the initial coordinates of each pixel in the original image based on spatial offset to obtain the corrected coordinates of each pixel.

[0105] S108. Calculate the pixel value corresponding to the corrected coordinates of each pixel using an interpolation method;

[0106] S109. Fill the calculated pixel values ​​into the initial coordinate positions of each pixel to obtain the target image.

[0107] In this embodiment, the computer device performs coordinate correction entirely based on software algorithms, eliminating the need for additional hardware eddy current compensation modules. This reduces the cost of eddy current compensation while implementing it through software algorithms.

[0108] In one embodiment, a magnetic resonance imaging method is provided, which specifically includes: acquiring raw magnetic resonance images corresponding to multiple diffusion gradient directions;

[0109] The original magnetic resonance image corresponding to each diffusion gradient direction is corrected to obtain the target image corresponding to each diffusion gradient direction;

[0110] The target images corresponding to multiple diffusion gradient directions are registered to the same normalized space to obtain a diffusion-synthesized image.

[0111] Optional registration methods include rigid registration or non-rigid registration.

[0112] Optionally, the diffusion gradient direction can be along the X-axis, Y-axis, or Z-axis, etc.

[0113] Optionally, the original magnetic resonance image corresponding to each diffusion gradient direction is corrected using the aforementioned method. Figure 2 Appendix Figure 9 The process method is shown. Furthermore, the raw MRI images can undergo preprocessing operations such as data format conversion, calculation of anisotropy values, or bone removal before correction.

[0114] The magnetic resonance image correction method provided in the above embodiments has a similar implementation principle and technical effect to the above method embodiments, and will not be described again here.

[0115] It should be understood that, although Figure 2-9 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 2-9 At least some of the steps in the process may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but may be executed at different times. The execution order of these steps or stages is not necessarily sequential, but may be executed in turn or alternately with other steps or at least some of the steps or stages in other steps.

[0116] In one embodiment, such as Figure 10 As shown, a magnetic resonance image correction device is provided, comprising: a determination module 01, a construction module 02, a correction module 03, and an imaging module 04, wherein:

[0117] The determination module 01 is used to obtain the initial coordinates of each pixel in the original image of the magnetic resonance scan;

[0118] Module 02 is used to determine the eddy current distortion function based on gradient eddy current configuration information and protocol information;

[0119] The correction module 03 is used to determine the spatial offset of each pixel based on the eddy current distortion function and the initial coordinates of each pixel. The spatial offset is generated by the deformation of the eddy current field. It also corrects the initial coordinates of each pixel in the original image based on the spatial offset to obtain the corrected coordinates of each pixel.

[0120] Imaging module 04 is used to obtain the corrected target image based on the corrected coordinates of each pixel.

[0121] In one embodiment, the protocol information includes the time interval between the eddy current field generated by the pixel's diffusion gradient rising and falling in various directions and reaching the center point of the k-space.

[0122] In one embodiment, the construction module 02 is used to determine the eddy current field polynomial based on the eddy current configuration file and protocol information; and to determine the eddy current distortion function based on the eddy current field polynomial.

[0123] In one embodiment, the eddy current distortion function includes a transverse distortion expression and a longitudinal distortion expression.

[0124] In one embodiment, the correction module 03 is used to transform the initial coordinates of each pixel to obtain the logical coordinates of each pixel; and to determine the spatial offset corresponding to the logical coordinates of each pixel according to the eddy current distortion function.

[0125] In one embodiment, the correction module 03 is used to perform gridding processing on the original image to obtain the grid coordinates of each pixel in the grid; and to traverse and substitute the grid coordinates of each pixel into the eddy current distortion function to obtain the spatial offset of each pixel.

[0126] In one embodiment, the imaging module 04 is used to calculate the calculated pixel value corresponding to the corrected coordinates of each pixel point through an interpolation method; and fill the calculated pixel value into the initial coordinate position of each pixel point to obtain the target image.

[0127] Specific limitations regarding the magnetic resonance image correction device can be found in the limitations of the magnetic resonance image correction method described above, and will not be repeated here. Each module in the aforementioned magnetic resonance image correction device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in hardware or independently of the processor in a computer device, or stored in software in the memory of a computer device, so that the processor can call and execute the corresponding operations of each module.

[0128] 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 perform the following steps:

[0129] Obtain the initial coordinates of each pixel in the original image of the magnetic resonance scan;

[0130] The eddy current distortion function is determined based on the gradient eddy current configuration information and protocol information;

[0131] Based on the eddy current distortion function and the initial coordinates of each pixel, the spatial offset of each pixel is determined. The spatial offset is generated by the deformation of the eddy current field.

[0132] The initial coordinates of each pixel in the original image are corrected based on spatial offset to obtain the corrected coordinates of each pixel; and the corrected target image is obtained based on the corrected coordinates of each pixel.

[0133] The computer device provided in the above embodiments has similar implementation principles and technical effects to the above method embodiments, and will not be described again here.

[0134] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0135] Obtain the initial coordinates of each pixel in the original image of the magnetic resonance scan;

[0136] The eddy current distortion function is determined based on the gradient eddy current configuration information and protocol information;

[0137] Based on the eddy current distortion function and the initial coordinates of each pixel, the spatial offset of each pixel is determined. The spatial offset is generated by the deformation of the eddy current field.

[0138] The initial coordinates of each pixel in the original image are corrected based on spatial offset to obtain the corrected coordinates of each pixel; and the corrected target image is obtained based on the corrected coordinates of each pixel.

[0139] The computer-readable storage medium provided in the above embodiments has similar implementation principles and technical effects to the above method embodiments, and will not be described again here.

[0140] 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, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, storage, 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, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0141] 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.

[0142] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. 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 patent application should be determined by the appended claims.

Claims

1. A method of correction of a magnetic resonance image, characterized in that, The method comprises: acquiring initial coordinates of each pixel point in a raw image of a magnetic resonance scan; determining a vortex distortion function according to gradient vortex configuration information and protocol information; determining spatial offsets of the each pixel point according to the vortex distortion function and the initial coordinates of the each pixel point, the spatial offsets being caused by deformation of a vortex field; correcting the initial coordinates of the each pixel point in the raw image based on the spatial offsets to obtain corrected coordinates of the each pixel point; and obtaining a corrected target image according to the corrected coordinates of the each pixel point; the determining of the vortex distortion function according to the gradient vortex configuration information and the protocol information comprises: determining a vortex field polynomial according to the gradient vortex configuration file, the vortex field polynomial being a function of a pixel point and a time interval; determining the vortex distortion function according to the vortex field polynomial and the protocol information.

2. The method of claim 1, wherein, The protocol information comprises time intervals at which vortex fields of the each pixel point generated when the each pixel point rises and falls on diffusion gradients in each direction reach a center point in k-space.

3. The method of claim 1, wherein, The vortex distortion function comprises a transverse distortion expression and a longitudinal distortion expression.

4. The method of claim 1, wherein, The determining of the spatial offsets of the each pixel point according to the vortex distortion function and the initial coordinates of the each pixel point comprises: transforming the initial coordinates of the each pixel point to obtain logical coordinates of the each pixel point; determining spatial offsets corresponding to the logical coordinates of the each pixel point according to the vortex distortion function.

5. The method of claim 4, wherein, The spatial offsets corresponding to the logical coordinates of the each pixel point are obtained by: performing grid processing on the raw image to obtain grid coordinates of the each pixel point in a grid; iterating the grid coordinates of the each pixel point into the vortex distortion function to obtain the spatial offsets of the each pixel point.

6. The method of claim 4, wherein, The target image is determined by: calculating a calculated pixel value corresponding to the corrected coordinates of the each pixel point by an interpolation method; filling the calculated pixel value to a position of the initial coordinates of the each pixel point to obtain the target image.

7. An apparatus for correcting a magnetic resonance image, characterized by The apparatus comprises: a determining module configured to acquire initial coordinates of each pixel point in a raw image of a magnetic resonance scan; a constructing module configured to determine a vortex distortion function according to gradient vortex configuration information and protocol information; a correcting module configured to determine spatial offsets of the each pixel point according to the vortex distortion function and the initial coordinates of the each pixel point, the spatial offsets being caused by deformation of a vortex field; and correct the initial coordinates of the each pixel point in the raw image based on the spatial offsets to obtain corrected coordinates of the each pixel point; an imaging module configured to obtain a corrected target image according to the corrected coordinates of the each pixel point; the determining of the vortex distortion function according to the gradient vortex configuration information and the protocol information comprises: determining a vortex field polynomial according to the gradient vortex configuration file, the vortex field polynomial being a function of a pixel point and a time interval; determining the vortex distortion function according to the vortex field polynomial and the protocol information.

8. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that, The processor implements the steps of the method of any one of claims 1 to 6 when executing the computer program.

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

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