Magnetic resonance imaging methods, apparatus and equipment for reducing radial acquisition sequence artifacts

Abstract

This invention discloses a method, apparatus, and device for reducing radial acquisition sequence artifacts in magnetic resonance imaging (MRI). The method includes: acquiring multiple sets of acquisition data obtained from multiple excitation radial scanning sequences; adjusting the acquisition direction of a portion of the acquisition data to obtain adjusted data; and performing image reconstruction based on the acquisition data and the adjusted data to obtain a reconstructed MRI image. The MRI method for reducing radial acquisition sequence artifacts provided by this invention solves the technical problems of uneven image reconstruction and obvious artifacts during radial acquisition, achieving the effect of reconstructing accurate and clear MRI images.

Description

Technical Field

[0001] This invention relates to the field of imaging technology, and in particular to a magnetic resonance imaging method, apparatus, and device for reducing radial acquisition sequence artifacts. Background Technology

[0002] Magnetic resonance imaging (MRI) plays a crucial role in medical diagnosis. However, when a patient moves during a scan, motion artifacts appear in the images calculated using conventional scanning methods, and severe motion artifacts can affect clinical diagnosis. Low-frequency signals in K-space primarily determine contrast, while high-frequency signals primarily determine detail. Acquiring MRI data radially yields more low-frequency K-space data and less high-frequency K-space data, ensuring the final image retains the main contrast characteristics without becoming blurry. This method of MRI data acquisition effectively reduces MRI image artifacts caused by patient movement.

[0003] Radial acquisition obtains projection data at different positions by rotating at different angles. This projection data is then used to grid the K-space. The signal of a point in the K-space will come from the contributions of different strips. This can reduce the obvious artifacts caused by motion-induced data defects in some strips, and at the same time, relatively good images can be obtained with fewer strips.

[0004] The radial acquisition sequence acquires data for one banner after a single excitation, and obtains data rotating around the center through multiple excitations. This data is then meshed to obtain complete K-space data. However, when the hardware system is not perfect, each banner data will have a certain offset, which will introduce obvious artifacts into the image. Summary of the Invention

[0005] This invention provides a magnetic resonance imaging method, apparatus, and device for reducing radial acquisition sequence artifacts, thereby solving the technical problems of uneven image reconstruction and obvious artifacts during radial acquisition, and achieving the effect of reconstructing accurate and clear magnetic resonance images.

[0006] According to one aspect of the present invention, a magnetic resonance imaging method for reducing radial acquisition sequence artifacts is provided, comprising: acquiring multiple sets of acquisition data obtained from multiple excitation radial scan sequences;

[0007] The collected data is adjusted to obtain the adjusted data;

[0008] Image reconstruction is performed based on the acquired and adjusted data to obtain a magnetic resonance reconstructed image.

[0009] According to another aspect of the present invention, a magnetic resonance imaging apparatus for reducing radial acquisition sequence artifacts is provided, comprising:

[0010] The data acquisition module is used to acquire multiple sets of data obtained from multiple excitation radial scan sequences.

[0011] The data acquisition adjustment module is used to adjust the acquired data to obtain adjusted data.

[0012] The magnetic resonance image reconstruction module is used to reconstruct images based on acquired and adjusted data to obtain reconstructed magnetic resonance images.

[0013] Optionally, based on the above scheme, the collection direction of some collected data can be adjusted to obtain adjusted data, including:

[0014] Based on the acquisition rotation angle, the acquired data is divided into data that does not need to be rearranged and data that needs to be rearranged.

[0015] The data to be rearranged is rearranged in terms of the collection direction to obtain rearranged data;

[0016] Treat the data that does not need to be rearranged and the data that needs to be rearranged as the adjustment data.

[0017] Optionally, based on the above scheme, image reconstruction is performed using the acquired and adjusted data to obtain a magnetic resonance reconstructed image, including:

[0018] K-space phase correction is performed on the acquired data to obtain phase-corrected data;

[0019] The adjusted data is then subjected to trajectory correction to obtain trajectory correction data.

[0020] Magnetic resonance reconstructed images are generated based on phase correction data and trajectory correction data.

[0021] Optionally, based on the above scheme, K-space phase correction is performed on the acquired data to obtain phase-corrected data, including:

[0022] For each set of collected data, a one-dimensional Fourier transform is performed on the collected data to obtain one-dimensional Fourier transform data.

[0023] Phase correction is performed point-by-point on all data in the one-dimensional Fourier transform data to obtain transform-corrected data;

[0024] Phase correction data is obtained by performing a one-dimensional inverse Fourier transform on the transformed correction data.

[0025] Optionally, based on the above scheme, trajectory correction is performed on the adjustment data to obtain trajectory correction data, including:

[0026] The trajectory movement deviation is obtained by processing the adjustment data, and the trajectory correction data is obtained based on the trajectory movement deviation and the original trajectory data.

[0027] Optionally, based on the above scheme, the adjustment data is processed to obtain the trajectory movement deviation, and trajectory correction data is obtained based on the trajectory movement deviation and the original trajectory data, including:

[0028] Treat two sets of adjustment data with opposite directions as a pair of processed data.

[0029] For each pair of processed data, the offset of the processed data is obtained based on the one-dimensional Fourier transform result of the processed data;

[0030] The target offset is obtained based on the offset of each pair of processed data, and the target offset is used as the trajectory movement deviation.

[0031] Substitute the trajectory movement deviation into the original trajectory data to obtain the offset of each original trajectory data, and obtain the trajectory correction data based on the offset of each original trajectory data.

[0032] Optionally, based on the above scheme, a magnetic resonance reconstructed image is generated based on phase correction data and trajectory correction data, including:

[0033] The phase correction data and trajectory correction data are gridded and then subjected to two-dimensional Fourier transform to obtain the magnetic resonance reconstructed image.

[0034] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0035] At least one processor; and

[0036] A memory that is communicatively connected to at least one processor; wherein,

[0037] The memory stores a computer program that can be executed by at least one processor, such that the at least one processor is able to perform a magnetic resonance imaging method for reducing radial acquisition sequence artifacts according to any embodiment of the present invention.

[0038] According to another aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium storing computer instructions for causing a processor to execute and implement the magnetic resonance imaging method for reducing radial acquisition sequence artifacts according to any embodiment of the present invention.

[0039] The technical solution of this invention involves acquiring multiple sets of data obtained from multiple excitation radial scanning sequences; adjusting the acquired data to obtain adjusted data; and performing image reconstruction based on the acquired data and adjusted data to obtain a magnetic resonance reconstructed image. This solves the technical problems of uneven reconstructed images and obvious artifacts during radial acquisition, achieving the effect of reconstructing accurate and clear magnetic resonance images.

[0040] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a flowchart of a magnetic resonance imaging method for reducing radial acquisition sequence artifacts provided in Embodiment 1 of the present invention;

[0043] Figure 2a This is a schematic diagram of the data reconstruction process in a magnetic resonance imaging method for reducing radial acquisition sequence artifacts provided in Embodiment 2 of the present invention;

[0044] Figure 2b This is a flowchart of a phase correction process provided in Embodiment 2 of the present invention;

[0045] Figure 2c This is a flowchart of a trajectory correction process provided in Embodiment 2 of the present invention;

[0046] Figure 2d This is a schematic diagram of an uncorrected magnetic resonance reconstruction image provided in Embodiment 2 of the present invention;

[0047] Figure 2e This is a schematic diagram of a magnetic resonance reconstruction image with phase correction provided in Embodiment 2 of the present invention;

[0048] Figure 2f This is a schematic diagram of a magnetic resonance reconstruction image after trajectory correction provided in Embodiment 2 of the present invention;

[0049] Figure 2g This is a schematic diagram of a magnetic resonance reconstructed image after combining phase correction and trajectory correction, provided in Embodiment 2 of the present invention;

[0050] Figure 3 This is a schematic diagram of the structure of a magnetic resonance imaging device for reducing radial acquisition sequence artifacts provided in Embodiment 3 of the present invention;

[0051] Figure 4 This is a schematic diagram of the structure of an electronic device for implementing the magnetic resonance imaging method for reducing radial acquisition sequence artifacts according to embodiments of the present invention. Detailed Implementation

[0052] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0053] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0054] Example 1

[0055] Figure 1 This is a flowchart of a magnetic resonance imaging method for reducing radial acquisition sequence artifacts according to Embodiment 1 of the present invention. This embodiment is applicable to the situation of reconstructing magnetic resonance images during radial scanning. The method can be executed by a magnetic resonance imaging device for reducing radial acquisition sequence artifacts. This magnetic resonance imaging device for reducing radial acquisition sequence artifacts can be implemented in hardware and / or software and can be configured in an electronic device. Figure 1 As shown, the method includes:

[0056] S110. Acquire multiple sets of data obtained from multiple excitation radial scan sequences.

[0057] This embodiment processes the acquired data obtained from radial scanning and performs image reconstruction based on the processed data to reduce artifacts in the magnetic resonance reconstructed image obtained from the acquired data.

[0058] Optionally, data acquisition can refer to the radial scanning data acquisition method in the prior art, and is not limited here. For example, the radial acquisition sequence acquisition trajectory parameters can be obtained, where the trajectory includes data from 0 to 2π (π); multiple excitations are performed, and the data of the corresponding banner obtained in each excitation is acquired as the acquisition data; after multiple excitations are completed, all the data required for radial acquisition sequence acquisition are obtained, that is, multiple sets of acquisition data are obtained, and each set of acquisition data is the data of one banner acquired in a single excitation.

[0059] S120. Adjust the acquisition direction of some of the collected data to obtain adjusted data.

[0060] After acquiring all the data used for image reconstruction, the acquired data is adjusted to obtain adjusted data. Image reconstruction is then performed based on the adjusted data to reduce acquisition deviations caused by the system or external factors, thereby reducing artifacts in the reconstructed magnetic resonance images and obtaining accurate and clear images.

[0061] Understandably, when performing an MRI scan on an object, ideally, two sets of data in opposite directions should correspond at the same location. However, hardware defects or the movement of the object itself can cause these two sets of data to not correspond at the same location. Therefore, the acquired data can be processed based on the differences between the oppositely oriented data to eliminate errors caused by external influences.

[0062] Based on the above, the acquisition direction of some of the collected data is adjusted to obtain adjusted data. This includes: dividing the collected data into data that does not need to be rearranged and data that needs to be rearranged based on the acquisition rotation angle; rearranging the acquisition direction of the data that needs to be rearranged to obtain rearranged data; and using the data that does not need to be rearranged and the rearranged data as adjusted data. Optionally, the collected data is divided into two groups according to the acquisition rotation angle corresponding to the collected data. One group does not require processing, and the other group needs to be rearranged in the acquisition direction. The data that needs to be rearranged is rearranged in the acquisition direction to obtain rearranged data, and the data consisting of the data that does not need to be rearranged and the rearranged data is used as adjusted data.

[0063] It is understandable that in a complete MRI scan, the data acquisition angle range is 0-360°. Data acquired in the 0-180° range and data acquired in the 180°-360° range are acquired in opposite directions. Based on this, a 180° acquisition rotation angle is used as the threshold for data division. Data acquired in the 0-180° range is considered the first group of data, and data acquired in the 180°-360° range is considered the second group of data. Either group of data can be rearranged to obtain rearranged data. Optionally, data acquired in the 0-180° range can be considered as data that does not need to be rearranged, and data acquired in the 180°-360° range can be rearranged in the acquisition direction; alternatively, data acquired in the 0-180° range can be rearranged in the acquisition direction, and data acquired in the 180°-360° range can be considered as data that does not need to be rearranged. Among them, rearranging the data to be rearranged by the acquisition direction can be done by adjusting the data position of the data to be rearranged according to the target acquisition direction of the rearrangement, so as to obtain the rearranged data after the acquisition direction of the data to be rearranged.

[0064] S130. Based on the acquired and adjusted data, image reconstruction is performed to obtain a magnetic resonance reconstructed image.

[0065] Overall, rearranging the acquisition direction of some data enabled phase compensation in K-space and mutual correction of opposite amplitudes on the trajectory, eliminating starburst artifacts. Phase compensation in K-space directly moved the echoes to the same position, resulting in good image correction and better detail, but with more significant starburst artifacts. Mutual correction of opposite amplitudes on the trajectory, using opposite acquisition data, also resulted in good image correction, with better overall image integrity and fewer starburst artifacts, but poorer image uniformity and some lost details. Therefore, combining phase and trajectory correction in data processing for image reconstruction yields a magnetic resonance imaging (MRI) reconstructed image with good integrity, good detail correction, and fewer starburst artifacts.

[0066] In one implementation, image reconstruction is performed based on acquired data and adjusted data to obtain a magnetic resonance reconstructed image. This includes: performing K-space phase correction on the acquired data to obtain phase-corrected data; performing trajectory correction on the adjusted data to obtain trajectory-corrected data; and generating a magnetic resonance reconstructed image based on the phase-corrected data and the trajectory-corrected data. Optionally, performing K-space phase correction on the acquired data specifically involves performing phase correction on all data points one by one. It is understood that performing a one-dimensional Fourier transform on the acquired data can project the acquired data into K-space; therefore, phase correction can be performed after projecting the acquired data into K-space.

[0067] Optionally, K-space phase correction is performed on the acquired data to obtain phase-corrected data. This includes: performing a one-dimensional Fourier transform on each set of acquired data to obtain one-dimensional Fourier transform data; performing phase correction on all data points within the one-dimensional Fourier transform data to obtain transform-corrected data; and performing a one-dimensional inverse Fourier transform on the transform-corrected data to obtain phase-corrected data. Specifically, a one-dimensional Fourier transform is performed on the acquired data to project it into K-space, obtaining one-dimensional Fourier transform data. Then, point-by-point phase correction is performed on the one-dimensional Fourier transform data projected into K-space to obtain transform-corrected data for each data point. Finally, an inverse one-dimensional Fourier transform is used to project the transform-corrected data from K-space back into the data space to obtain phase-corrected data.

[0068] Optionally, trajectory correction is performed on the adjustment data to obtain trajectory correction data, including: processing the adjustment data to obtain trajectory movement deviation, and obtaining trajectory correction data based on the trajectory movement deviation and the original trajectory data. In one implementation, trajectory offset can be performed for each banner data, i.e., each adjustment data, to obtain the correction trajectory for each group of adjustment data, and the correction trajectories of each group of adjustment data can be combined to obtain the actual trajectory data, i.e., the trajectory correction data.

[0069] In one embodiment, the adjustment data is processed to obtain a trajectory movement deviation, and trajectory correction data is obtained based on the trajectory movement deviation and the original trajectory data. This includes: treating two sets of adjustment data with opposite directions in the adjustment data as a pair of processed data; for each pair of processed data, obtaining the offset of the processed data based on the one-dimensional Fourier transform result; obtaining a target offset based on the offset of each pair of processed data, and using the target offset as the trajectory movement deviation; substituting the trajectory movement deviation into the original trajectory data to obtain the offset of each original trajectory data, and obtaining trajectory correction data based on the offset of each original trajectory data. Optionally, the adjustment data is divided into multiple pairs of processed data, and for each pair of processed data, the offset of that pair is calculated. The target offset is determined as the trajectory movement deviation based on the offsets of all pairs of processed data, and then the trajectory correction data is obtained based on the trajectory movement deviation and the original trajectory data. After trajectory correction, actual trajectory data can be obtained to solve the gradient asymmetry problem caused by the instability of the scanning system.

[0070] Based on the above scheme, a magnetic resonance reconstructed image is generated based on phase correction data and trajectory correction data. This includes: performing a two-dimensional Fourier transform on the phase correction data and trajectory correction data after gridding to obtain the magnetic resonance reconstructed image. After obtaining phase correction data and trajectory correction data, the obtained phase correction data and trajectory correction data are gridded and then subjected to a two-dimensional Fourier transform to obtain the magnetic resonance reconstructed image. Rearranging the acquisition direction of some acquired data achieves phase compensation in K-space and mutual correction of opposite amplitudes on the trajectory, eliminating starburst artifacts. Phase compensation in K-space directly moves the echoes to the same position, which can correct the image well, and the details in the image are well corrected, but the starburst artifacts are larger. Mutual correction of opposite amplitudes on the trajectory, using opposite acquired data for correction, can correct the image well, with good overall image integrity and smaller starburst artifacts, but the image uniformity is poorer, and some details in the image are ignored. By combining phase correction and trajectory correction to process the data and then reconstructing the image, we can obtain a magnetic resonance reconstructed image with good image integrity, good detail correction, and small star artifacts.

[0071] The technical solution of this embodiment obtains multiple sets of acquired data by acquiring multiple excitation radial scanning sequences; adjusts the acquired data to obtain adjusted data; and performs image reconstruction based on the acquired data and adjusted data to obtain a magnetic resonance reconstructed image. This solves the technical problems of uneven reconstructed images and obvious artifacts during radial acquisition, and achieves the effect of reconstructing accurate and clear magnetic resonance images.

[0072] Example 2

[0073] This embodiment provides a preferred embodiment based on the above embodiments.

[0074] The magnetic resonance imaging method for reducing radial acquisition sequence artifacts provided in this embodiment includes two parts: data acquisition and data reconstruction.

[0075] Optionally, the data acquisition section may include:

[0076] Step 1: Obtain the radial acquisition sequence trajectory parameters, where the trajectory includes data from 0 to 2π;

[0077] Step 2: Perform the first activation and collect data from the first banner (i.e., a set of collected data);

[0078] Step 3: Repeat step 2 to obtain all the data required for radial acquisition sequence acquisition.

[0079] Figure 2a This is a schematic diagram of the data reconstruction process in a magnetic resonance imaging method for reducing radial acquisition sequence artifacts, provided in Embodiment 2 of the present invention. Figure 2a As shown, the data reconstruction section may include:

[0080] S210. Adjust the collected data.

[0081] Optionally, adjusting the collected data may include:

[0082] (1) Divide the opposite banner data into two groups;

[0083] (2) Rearrange the acquisition direction of the data with a rotation angle greater than π in the opposite banner data.

[0084] S220. The adjusted data is processed to obtain the magnetic resonance reconstructed image.

[0085] Optionally, adjusting the collected data may include:

[0086] (3) Perform K-space phase correction on the acquired data;

[0087] Figure 2b This is a flowchart of a phase correction process provided in Embodiment 2 of the present invention. Figure 2b As shown, phase correction is performed on the acquired data to obtain phase-corrected K-space data.

[0088] (4) Process the adjusted data to obtain the trajectory movement deviation, and perform trajectory correction;

[0089] Figure 2c This is a flowchart of a trajectory correction process provided in Embodiment 2 of the present invention. Figure 2cAs shown, the collected data is rearranged, trajectory deviation is calculated, and trajectory is corrected to obtain the actual trajectory after trajectory correction.

[0090] (5) The processed K-space data and the corrected trajectory are gridded, and finally 2DIFFT2 transformation is performed to obtain the image.

[0091] Based on the above scheme, step (3) of performing K-space phase correction on the acquired data may include:

[0092] (6) Perform a one-dimensional FT transformation on the collected data to obtain the original data Raw and the data RAW_FT transformed by the one-dimensional FT: RAW_FT = 1DFT(RAW);

[0093] (7) Perform phase correction on all data in Raw_FT point by point to obtain data Raw_FT: Raw_FT'=exp(-i*angle(1DFT(Raw)))*Raw, where exp means to perform exponential operation and angle means to take the phase;

[0094] (8) Perform a one-dimensional inverse Fourier transform on Raw_FT' to obtain the data Raw':

[0095] Raw' = 1DIFT(Raw_FT');

[0096] (9) Perform steps (6)-(8) on all data to obtain K-space phase-corrected data.

[0097] Based on the above scheme, step (4) processes the adjusted data to obtain the trajectory movement deviation and performs trajectory correction, which may include:

[0098] (10) For the adjusted data, perform a one-dimensional FT transformation on one banner and multiply it with the conjugate of the one-dimensional FT transformation on the opposite banner to obtain g(x): g(x)=FT(S0(t))*Conj(S180(t));

[0099] conj(x) represents taking the conjugate of x, S0 represents the banner data with a rotation angle of 0, and 180 represents the banner data with a rotation angle of pi;

[0100] (11) Take the slope of the phase of the part with larger signal amplitude among the above points to obtain the phase shift after FT transformation. The displacement result before FT transformation is Shift:

[0101] Shift = -Slope(angel(g(x)))*nx / (2*pi), where Slope represents the slope;

[0102] (12) Perform steps (10)-(11) for all opposite pairs of stripes to obtain the offset of each pair of stripes. These offset results are derived from the gradient at different angular components. Averaging them yields an average offset S_delter. The calculation process is as follows:

[0103] S_delter*[(cos^2(f), sin^2(f), 2*cos(f)*sin(f)),…]=shift;

[0104] (13) Substitute the calculated average offset into the trajectory of each banner to obtain the offset of each banner, and then obtain the actual trajectory.

[0105] Finally, by performing a 2DIFFT transformation on the obtained K-space data and the actual trajectory, the magnetic resonance reconstruction can be obtained.

[0106] It should be noted that this embodiment reconstructs magnetic resonance images using uncorrected, single-corrected, and combined-corrected methods. Figure 2d This is a schematic diagram of an uncorrected magnetic resonance reconstruction image provided in Embodiment 2 of the present invention; Figure 2e This is a schematic diagram of a magnetic resonance reconstruction image with phase correction provided in Embodiment 2 of the present invention; Figure 2f This is a schematic diagram of a magnetic resonance reconstruction image after trajectory correction provided in Embodiment 2 of the present invention; Figure 2g This is a schematic diagram of a magnetic resonance reconstructed image after combining phase correction and trajectory correction, provided in Embodiment 2 of the present invention. By comparison... Figure 2d and Figure 2e It can be seen that phase correction can eliminate starburst artifacts and motion artifacts in magnetic resonance reconstructed images; by comparison Figure 2d and Figure 2f It can be seen that trajectory correction can resolve the asymmetry problem in the reconstructed magnetic resonance images. Through comparison... Figure 2d and Figure 2g It is evident that by using a combination of phase correction and trajectory correction, starburst artifacts in the reconstructed magnetic resonance images can be eliminated, and the problem of inhomogeneity in the reconstructed magnetic resonance images can be resolved.

[0107] This invention employs a combination of two correction methods: acquiring opposing banner data with rotation angles between 0 and 2π, performing phase correction on the K-space data, and trajectory correction on the opposing banner data. This reduces artifacts caused by hardware imperfections without significantly increasing scan time. Specifically, after data rearrangement, phase compensation is performed in K-space, and mutual correction of opposing banners is performed on the trajectory, eliminating starburst artifacts and motion artifacts. Phase compensation in K-space addresses echo center offset caused by gradient delay, and mutual correction of opposing banners on the trajectory resolves gradient asymmetry issues caused by system instability.

[0108] Example 3

[0109] Figure 3 This is a schematic diagram of a magnetic resonance imaging device for reducing radial acquisition sequence artifacts, provided in Embodiment 3 of the present invention. Figure 3 As shown, the device includes: a data acquisition module 310, a data adjustment module 320, and a magnetic resonance image reconstruction module 330, wherein:

[0110] The data acquisition module 310 is used to acquire multiple sets of data obtained from multiple excitation radial scanning sequences;

[0111] The data acquisition adjustment module 320 is used to adjust the acquired data to obtain adjusted data;

[0112] The magnetic resonance image reconstruction module 330 is used to reconstruct images based on acquired and adjusted data to obtain magnetic resonance reconstructed images.

[0113] The technical solution of this embodiment obtains multiple sets of acquired data by acquiring multiple excitation radial scanning sequences; adjusts the acquired data to obtain adjusted data; and performs image reconstruction based on the acquired data and adjusted data to obtain a magnetic resonance reconstructed image. This solves the technical problems of uneven reconstructed images and obvious artifacts during radial acquisition, and achieves the effect of reconstructing accurate and clear magnetic resonance images.

[0114] Based on the above embodiments, optionally, the data acquisition adjustment module 320 is specifically used for:

[0115] Based on the acquisition rotation angle, the acquired data is divided into data that does not need to be rearranged and data that needs to be rearranged.

[0116] The data to be rearranged is rearranged in terms of the collection direction to obtain rearranged data;

[0117] Treat the data that does not need to be rearranged and the data that needs to be rearranged as the adjustment data.

[0118] Based on the above embodiments, the magnetic resonance image reconstruction module 330 includes:

[0119] The phase correction unit is used to perform K-space phase correction on the acquired data to obtain phase-corrected data;

[0120] The trajectory correction unit is used to correct the trajectory of the adjustment data to obtain trajectory correction data.

[0121] The image reconstruction unit is used to generate magnetic resonance reconstructed images based on phase correction data and trajectory correction data.

[0122] Based on the above embodiments, optionally, the phase correction unit is specifically used for:

[0123] For each set of collected data, a one-dimensional Fourier transform is performed on the collected data to obtain one-dimensional Fourier transform data.

[0124] Phase correction is performed point-by-point on all data in the one-dimensional Fourier transform data to obtain transform-corrected data;

[0125] Phase correction data is obtained by performing a one-dimensional inverse Fourier transform on the transformed correction data.

[0126] Based on the above embodiments, optionally, the trajectory correction unit is specifically used for:

[0127] The trajectory movement deviation is obtained by processing the adjustment data, and the trajectory correction data is obtained based on the trajectory movement deviation and the original trajectory data.

[0128] Based on the above embodiments, optionally, the trajectory correction unit is specifically used for:

[0129] Treat two sets of adjustment data with opposite directions as a pair of processed data.

[0130] For each pair of processed data, the offset of the processed data is obtained based on the one-dimensional Fourier transform result of the processed data;

[0131] The target offset is obtained based on the offset of each pair of processed data, and the target offset is used as the trajectory movement deviation.

[0132] Substitute the trajectory movement deviation into the original trajectory data to obtain the offset of each original trajectory data, and obtain the trajectory correction data based on the offset of each original trajectory data.

[0133] Based on the above embodiments, optionally, the image reconstruction unit is specifically used for:

[0134] The phase correction data and trajectory correction data are gridded and then subjected to two-dimensional Fourier transform to obtain the magnetic resonance reconstructed image.

[0135] The magnetic resonance imaging apparatus for reducing radial acquisition sequence artifacts provided in the embodiments of the present invention can execute the magnetic resonance imaging method for reducing radial acquisition sequence artifacts provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects for executing the method.

[0136] Example 4

[0137] Figure 4 This is a schematic diagram of an electronic device for implementing the magnetic resonance imaging method for reducing radial acquisition sequence artifacts according to embodiments of the present invention. The electronic device 10 is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0138] like Figure 4 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 may also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0139] Multiple components in electronic device 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0140] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as magnetic resonance imaging methods for reducing radial acquisition sequence artifacts.

[0141] In some embodiments, the magnetic resonance imaging method for reducing radial acquisition sequence artifacts can be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or mounted on electronic device 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the magnetic resonance imaging method for reducing radial acquisition sequence artifacts described above can be performed. Alternatively, in other embodiments, processor 11 can be configured to perform the magnetic resonance imaging method for reducing radial acquisition sequence artifacts by any other suitable means (e.g., by means of firmware).

[0142] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0143] Computer programs for implementing the magnetic resonance imaging method for reducing radial acquisition sequence artifacts of the present invention can be written in any combination of one or more programming languages. These computer programs can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The computer programs can be executed entirely on the machine, partially on the machine, as a standalone software package partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0144] Example 5

[0145] Embodiment 5 of the present invention also provides a computer-readable storage medium storing computer instructions for causing a processor to execute a magnetic resonance imaging method for reducing radial acquisition sequence artifacts, the method comprising:

[0146] Multiple sets of acquired data were obtained from multiple excitation radial scan sequences;

[0147] The collected data is adjusted to obtain adjusted data;

[0148] Based on the acquired data and the adjusted data, image reconstruction is performed to obtain a magnetic resonance reconstructed image.

[0149] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0150] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0151] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0152] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0153] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0154] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A magnetic resonance imaging method for reducing radial acquisition sequence artifacts, characterized in that, include: Multiple sets of acquired data were obtained from multiple excitation radial scan sequences; The acquisition direction of some of the collected data is adjusted to obtain adjusted data; Based on the acquired data and the adjusted data, image reconstruction is performed to obtain a magnetic resonance reconstructed image; The step of adjusting the acquisition direction of a portion of the acquired data to obtain adjusted data includes: Based on the acquisition rotation angle of the acquired data, the acquired data is divided into data that does not need to be rearranged and data that needs to be rearranged. The data to be rearranged is rearranged by the acquisition direction to obtain rearranged data; The data that does not need to be rearranged and the rearranged data are used as the adjustment data; The step of dividing the collected data into data that does not need to be rearranged and data that needs to be rearranged based on the acquisition rotation angle includes: Data collected with a rotation angle between 0 and 180° is considered as data that does not need to be rearranged, while data collected with a rotation angle between 180° and 360° is considered as data to be rearranged and the acquisition direction is rearranged. The step of performing image reconstruction based on the acquired data and the adjusted data to obtain a magnetic resonance reconstructed image includes: The acquired data is subjected to K-space phase correction to obtain phase-corrected data; The adjusted data is then subjected to trajectory correction to obtain trajectory correction data; The magnetic resonance reconstructed image is generated based on the phase correction data and the trajectory correction data; The step of performing trajectory correction on the adjusted data to obtain trajectory correction data includes: The adjustment data is processed to obtain the trajectory movement deviation, and the trajectory correction data is obtained based on the trajectory movement deviation and the original trajectory data. The process of processing the adjustment data to obtain the trajectory movement deviation, and obtaining the trajectory correction data based on the trajectory movement deviation and the original trajectory data, includes: Two sets of adjustment data with opposite directions in the adjustment data are treated as a pair of processing data; For each pair of processed data, the offset of the processed data is obtained based on the one-dimensional Fourier transform result of the processed data; The target offset is obtained based on the offset of each pair of processed data, and the target offset is used as the trajectory movement deviation; Substitute the trajectory movement deviation into the original trajectory data to obtain the offset of each original trajectory data, and obtain the trajectory correction data based on the offset of each original trajectory data.

2. The method according to claim 1, characterized in that, The step of performing K-space phase correction on the acquired data to obtain phase-corrected data includes: For each set of collected data, a one-dimensional Fourier transform is performed on the collected data to obtain one-dimensional Fourier transform data; Phase correction is performed point-by-point on all data in the one-dimensional Fourier transform data to obtain transform-corrected data; The phase correction data is obtained by performing a one-dimensional inverse Fourier transform on the transformed correction data.

3. The method according to claim 1, characterized in that, The process of generating the magnetic resonance reconstructed image based on the phase correction data and the trajectory correction data includes: The phase correction data and the trajectory correction data are gridded and then subjected to a two-dimensional Fourier transform to obtain the magnetic resonance reconstructed image.

4. A magnetic resonance imaging device for reducing radial acquisition sequence artifacts, characterized in that, include: The data acquisition module is used to acquire multiple sets of data obtained from multiple excitation radial scan sequences. The data acquisition adjustment module is used to adjust the acquired data to obtain adjusted data; A magnetic resonance image reconstruction module is used to reconstruct an image based on the acquired data and the adjusted data to obtain a magnetic resonance reconstructed image. Specifically, the data collection adjustment module is used for: Based on the acquisition rotation angle of the acquired data, the acquired data is divided into data that does not need to be rearranged and data that needs to be rearranged. The data to be rearranged is rearranged by the acquisition direction to obtain rearranged data; The data that does not need to be rearranged and the rearranged data are used as the adjustment data; The step of dividing the collected data into data that does not need to be rearranged and data that needs to be rearranged based on the acquisition rotation angle includes: Data collected with a rotation angle between 0 and 180° is considered as data that does not need to be rearranged, while data collected with a rotation angle between 180° and 360° is considered as data to be rearranged and the acquisition direction is rearranged. The magnetic resonance image reconstruction module includes: A phase correction unit is used to perform K-space phase correction on the acquired data to obtain phase-corrected data; A trajectory correction unit is used to perform trajectory correction on the adjustment data to obtain trajectory correction data; An image reconstruction unit is used to generate the magnetic resonance reconstructed image based on the phase correction data and the trajectory correction data; The trajectory correction unit is further used for: The trajectory movement deviation is obtained by processing the adjustment data, and the trajectory correction data is obtained based on the trajectory movement deviation and the original trajectory data. Specifically, the trajectory correction unit is used for: Treat two sets of adjustment data with opposite directions as a pair of processed data. For each pair of processed data, the offset of the processed data is obtained based on the one-dimensional Fourier transform result of the processed data; The target offset is obtained based on the offset of each pair of processed data, and the target offset is used as the trajectory movement deviation. Substitute the trajectory movement deviation into the original trajectory data to obtain the offset of each original trajectory data, and obtain the trajectory correction data based on the offset of each original trajectory data.

5. An electronic device, characterized in that, The electronic device includes: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the magnetic resonance imaging method for reducing radial acquisition sequence artifacts as described in any one of claims 1-3.

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed by a processor, implement the magnetic resonance imaging method for reducing radial acquisition sequence artifacts as described in any one of claims 1-3.

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