Micro-quantitative magnetic sensitivity imaging method and related equipment based on ultra-fast scanning

Abstract

The present invention provides a micro-quantitative magnetic susceptibility imaging method based on ultra-fast scanning and related equipment, which can acquire micro-quantitative magnetic susceptibility imaging with high signal-to-noise ratio and ultra-high resolution. The method includes: acquiring two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images; performing distortion correction on the first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image, and nonlinearly registering the distortion-corrected image to the coordinate space of the high-resolution image; performing upsampling processing on the registered image; performing magnetic susceptibility separation processing on the up-sampled image to determine a second high-resolution image, which includes the magnetization distribution of paramagnetic substances and the magnetization distribution of diamagnetic substances; processing the local field in the second high-resolution image by a voxel-specific attenuation kernel, and performing deconvolution processing to obtain the micro-quantitative magnetic susceptibility imaging corresponding to the target brain.

Description

Technical Field

[0001] The invention relates to the field of medical image processing, and in particular to a micro-quantitative magnetic sensitivity imaging method based on ultra-fast scanning and related equipment. Background Art

[0002] In the field of magnetic resonance imaging, it is crucial to accurately quantify the paramagnetic and diamagnetic susceptibility of tissues, as these parameters are closely related to the physiological and pathological states of tissues. Quantitative Susceptibility Mapping (QSM) is a promising non-invasive magnetic resonance imaging technique that can quantify the volumetric susceptibility of tissues.

[0003] Nevertheless, traditional high-resolution QSM technology has the problem of long scanning time and can only provide voxel average magnetic susceptibility values, and cannot distinguish the positive and negative signs of the magnetic susceptibility within the voxel. This limitation restricts the wider application of QSM in studying brain development and neurodegenerative diseases. Summary of the invention

[0004] The embodiment of the present invention provides a micro-quantitative magnetic susceptibility imaging method based on ultra-fast scanning and related equipment, which can acquire micro-quantitative magnetic susceptibility imaging with high signal-to-noise ratio and ultra-high resolution.

[0005] The first aspect of the present invention provides a micro-quantitative magnetic susceptibility imaging method based on ultra-fast scanning, comprising:

[0006] Acquire multiple two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images of the target brain;

[0007] Performing distortion correction on a first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging, wherein the first two-dimensional multi-band echo planar imaging is any one of the multiple two-dimensional multi-band echo planar imaging;

[0008] nonlinearly registering the second two-dimensional multi-band echo planar imaging into the coordinate space of the high-resolution image to obtain a target registered image;

[0009] Performing upsampling processing on the target registration image to obtain a first high-resolution image;

[0010] Processing the first high-resolution image based on a pre-constructed iterative algorithm model of magnetic susceptibility separation to determine a second high-resolution image, wherein the second high-resolution image includes a magnetization distribution of the paramagnetic substance and a magnetization distribution of the diamagnetic substance;

[0011] Processing the local field in the second high-resolution image by a voxel-specific attenuation kernel to obtain a third high-resolution image;

[0012] The third high-resolution image is subjected to a deconvolution process to obtain a micro-quantified magnetic susceptibility imaging corresponding to the target brain.

[0013] In a possible design, the performing distortion correction on the first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain the second two-dimensional multi-band echo planar imaging includes:

[0014] Determine a phase difference image based on two images with different echo times selected from the three-dimensional gradient echo scanning image;

[0015] estimating a distortion field according to the phase difference image;

[0016] adjusting the correction strength according to the degree of distortion and quality of the two-dimensional multi-band echo planar image;

[0017] The target distorted image is corrected based on the adjusted correction intensity and the distortion field to eliminate geometric distortion caused by magnetic field inhomogeneity, thereby obtaining the second two-dimensional multi-band echo planar imaging.

[0018] In a possible design, the iterative algorithm model based on the pre-built magnetic susceptibility separation processes the first high-resolution image to determine the second high-resolution image, including:

[0019] Step 1: estimating the magnetic susceptibility distribution corresponding to the first high-resolution image according to the phase data of the first high-resolution image;

[0020] Step 2, initializing the magnetic susceptibility distribution;

[0021] Step 3, decomposing the phase data into a first magnetic susceptibility of the paramagnetic material and a second magnetic susceptibility of the diamagnetic material;

[0022] Step 4, updating the initialized magnetic susceptibility distribution according to the first magnetic susceptibility and the second magnetic susceptibility;

[0023] Step 5: iteratively execute steps 3 and 4 based on the updated magnetic susceptibility distribution, and adjust the weights during the iterative execution by multi-scale iterative reweighted least squares method until a preset iteration termination condition is reached to obtain the second high-resolution image.

[0024] In a possible design, estimating the magnetic susceptibility distribution corresponding to the first high-resolution image according to the phase data of the first high-resolution image includes:

[0025] The magnetic susceptibility distribution is determined by the following formula:

[0026]

[0027] Where k is the magnetic susceptibility distribution, B curl is the eddy current field corresponding to the first high-resolution image, d is the distance of the local field corresponding to the first high-resolution image, λ is the regularization parameter, B curl =B0-B macro , B0 is the background field corresponding to the first high-resolution image, B macro is the macroscopic magnetic field of the background field;

[0028] In a possible design, updating the initialized magnetic susceptibility distribution according to the first magnetic susceptibility and the second magnetic susceptibility includes:

[0029] The magnetic susceptibility distribution after initialization is updated by the following formula:

[0030]

[0031] Among them, k p is the first magnetic susceptibility, k d is the second magnetic susceptibility, φ is the phase data, φ=φ0+k p ·dk d ·d, φ0 is the background phase corresponding to the first high-resolution image.

[0032] In a possible design, the processing of the local field in the second high-resolution image by using a voxel-specific attenuation kernel to obtain a third high-resolution image includes:

[0033] The local field in the second high-resolution image is processed by the following formula to obtain a third high-resolution image:

[0034]

[0035] Wherein, L(x) is the local field at position x in the second high-resolution image, K(x,y) is the voxel-specific attenuation kernel at the position x, B0(y) is the background field at position y in the second high-resolution image, Ω is the imaging volume corresponding to the second high-resolution image, and dy is the distance of the local field at the position y.

[0036] In one possible design, the acquiring of multiple two-dimensional multi-band echo planar images of the target brain includes:

[0037] Determining the sagittal, transverse and coronal positions corresponding to the target brain;

[0038] The imaging of the target brain is acquired based on the sagittal position, the transverse position, and the coronal position to obtain the multiple two-dimensional multi-band echo planar images.

[0039] The second aspect of the present invention provides a micro-quantitative magnetic sensitive imaging device based on ultra-fast scanning, comprising:

[0040] An acquisition unit, used for acquiring a plurality of two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images of the target brain;

[0041] a distortion correction unit, configured to perform distortion correction on a first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging, wherein the first two-dimensional multi-band echo planar imaging is any one of the multiple two-dimensional multi-band echo planar imaging;

[0042] A nonlinear registration unit, used for nonlinearly registering the second two-dimensional multi-band echo planar imaging into the coordinate space of the high-resolution image to obtain a target registered image;

[0043] An upsampling unit, configured to perform upsampling processing on the target registration image to obtain a first high-resolution image;

[0044] A magnetic susceptibility separation unit, configured to process the first high-resolution image based on a pre-constructed iterative algorithm model of magnetic susceptibility separation to determine a second high-resolution image, wherein the second high-resolution image includes a magnetization distribution of the paramagnetic substance and a magnetization distribution of the diamagnetic substance;

[0045] a local field processing unit, configured to process the local field in the second high-resolution image by using a voxel-specific attenuation kernel to obtain a third high-resolution image;

[0046] A convolution processing unit is used to perform deconvolution processing on the third high-resolution image to obtain micro-quantified magnetic susceptibility imaging corresponding to the target brain.

[0047] In a possible design, the distortion correction unit is specifically used for:

[0048] Determine a phase difference image based on two images with different echo times selected from the three-dimensional gradient echo scanning image;

[0049] estimating a distortion field according to the phase difference image;

[0050] adjusting the correction strength according to the degree of distortion and quality of the two-dimensional multi-band echo planar image;

[0051] The target distorted image is corrected based on the adjusted correction intensity and the distortion field to eliminate geometric distortion caused by magnetic field inhomogeneity, thereby obtaining the second two-dimensional multi-band echo planar imaging.

[0052] In a possible design, the magnetic susceptibility separation unit is specifically used for:

[0053] Step 1: estimating the magnetic susceptibility distribution corresponding to the first high-resolution image according to the phase data of the first high-resolution image;

[0054] Step 2, initializing the magnetic susceptibility distribution;

[0055] Step 3, decomposing the phase data into a first magnetic susceptibility of the paramagnetic material and a second magnetic susceptibility of the diamagnetic material;

[0056] Step 4, updating the initialized magnetic susceptibility distribution according to the first magnetic susceptibility and the second magnetic susceptibility;

[0057] Step 5: iteratively execute steps 3 and 4 based on the updated magnetic susceptibility distribution, and adjust the weights during the iterative execution by multi-scale iterative reweighted least squares method until a preset iteration termination condition is reached to obtain the second high-resolution image.

[0058] In a possible design, the magnetic susceptibility separation unit is further specifically used for:

[0059] The magnetic susceptibility distribution is determined by the following formula:

[0060]

[0061] Where k is the magnetic susceptibility distribution, B curl is the eddy current field corresponding to the first high-resolution image, d is the distance of the local field corresponding to the first high-resolution image, λ is the regularization parameter, B curl =B0-B macro , B0 is the background field corresponding to the first high-resolution image, B macro is the macroscopic magnetic field of the background field;

[0062] In a possible design, the magnetic susceptibility separation unit is further specifically used for:

[0063] The magnetic susceptibility distribution after initialization is updated by the following formula:

[0064]

[0065] Among them, k p is the first magnetic susceptibility, k dis the second magnetic susceptibility, φ is the phase data, φ=φ0+k p ·dk d ·d, φ0 is the background phase corresponding to the first high-resolution image.

[0066] In a possible design, the local field processing unit is specifically used for:

[0067] The local field in the second high-resolution image is processed by the following formula to obtain a third high-resolution image:

[0068]

[0069] Wherein, L(x) is the local field at position x in the second high-resolution image, K(x,y) is the voxel-specific attenuation kernel at the position x, B0(y) is the background field at position y in the second high-resolution image, Ω is the imaging volume corresponding to the second high-resolution image, and dy is the distance of the local field at the position y.

[0070] In a possible design, the acquisition unit is specifically used for:

[0071] Determining the sagittal, transverse and coronal positions corresponding to the target brain;

[0072] The imaging of the target brain is acquired based on the sagittal position, the transverse position, and the coronal position to obtain the multiple two-dimensional multi-band echo planar images.

[0073] The third aspect of the present invention provides an electronic device, comprising a memory and a processor, wherein the processor is used to implement the steps of the ultra-fast scanning based micro-quantitative magnetic susceptibility imaging method as described in the first aspect when executing a computer management program stored in the memory.

[0074] The fourth aspect of the present invention provides a computer-readable storage medium having a computer management program stored thereon, which, when executed by a processor, implements the steps of the ultrafast scanning-based micro-quantitative magnetic susceptibility imaging method as described in the first aspect above.

[0075] In summary, it can be seen that in the embodiment provided by the present invention, the two-dimensional multi-band echo planar imaging is corrected by the collected three-dimensional gradient echo scanning image, and the corrected image is subjected to nonlinear processing and up-sampling, and the magnetization distribution of the paramagnetic material and the diamagnetic material is determined for the up-sampled image, and the local field processing and deconvolution processing are performed by the voxel-specific attenuation kernel, thereby obtaining the micro-quantitative magnetic susceptibility imaging. Therefore, through reconstruction technology and image processing algorithms, the resolution and scanning efficiency of QSM are improved, and the magnetic susceptibility distribution of the paramagnetic material and the magnetic susceptibility distribution of the diamagnetic material in the subvoxel can be distinguished, thereby overcoming the limitations of the traditional high-resolution QSM method, and obtaining micro-quantitative magnetic susceptibility imaging with high signal-to-noise ratio and ultra-high resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Figure 1 An architecture diagram of a micro-quantitative magnetically sensitive imaging system based on ultra-fast scanning provided by an embodiment of the present invention;

[0077] Figure 2 A schematic diagram of a process flow of a micro-quantitative magnetic sensitivity imaging method based on ultra-fast scanning provided by an embodiment of the present invention;

[0078] Figure 3 A virtual structural diagram of a micro-quantitative magnetically sensitive imaging device based on ultra-fast scanning provided by an embodiment of the present invention;

[0079] Figure 4 A schematic diagram of the hardware structure of a micro-quantitative magnetically sensitive imaging device based on ultra-fast scanning provided by an embodiment of the present invention;

[0080] Figure 5 A schematic diagram of an electronic device according to an embodiment of the present invention;

[0081] Figure 6 A schematic diagram of an embodiment of a computer-readable storage medium provided for an embodiment of the present invention. DETAILED DESCRIPTION

[0082] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0083] In the following description, specific embodiments of the present invention will be described with reference to steps and symbols performed by one or more computers, unless otherwise stated. Therefore, these steps and operations will be referred to as being performed by a computer several times, and computer execution referred to herein includes the operation of a computer processing unit by electronic signals representing data in a structured form. This operation transforms the data or maintains it at a location in the memory system of the computer, which can be reconfigured or otherwise change the operation of the computer in a manner familiar to those skilled in the art. The data structure in which the data is maintained is a physical location in the memory, which has specific characteristics defined by the data format. However, the principles of the present invention are described in the above text, which does not represent a limitation, and those skilled in the art will understand that the various steps and operations described below can also be implemented in hardware.

[0084] The principles of the present invention operate with many other general or special purpose computing, communication environments or configurations. Examples of well-known computing systems, environments and configurations suitable for use with the present invention may include, but are not limited to, handheld phones, personal computers, servers, multiprocessor systems, microcomputer-based systems, mainframe computers, and distributed computing environments, including any of the above systems or devices.

[0085] The terms "first", "second", and "third" in the present invention are used to distinguish different objects rather than to describe a specific order. In addition, the terms "include", "have", and any variations thereof are intended to cover non-exclusive inclusions.

[0086] See also Figure 1 , Figure 1 The architecture diagram of the micro-quantitative magnetic sensitivity imaging system based on ultra-fast scanning provided by the embodiment of the present invention includes a high-field strength MRI scanner and a multi-channel receiving coil (module 1), a dedicated image processing workstation (module 2) and a maintenance system (module 3). The dedicated image processing workstation is equipped with high-performance hardware and necessary software tools (such as MATLAB and Python) for data acquisition, image reconstruction and magnetic susceptibility quantification. The following are detailed descriptions:

[0087] Module 1 is used to acquire MRI data, scan the subject using a high-field MRI scanner and a multi-channel receiving coil, optimize the pulse sequence, and minimize the scanning time.

[0088] The advanced image processing workstation in Template 2 is mainly used for:

[0089] 1. Image preprocessing and image reconstruction: Reconstruct high-resolution magnetic susceptibility images;

[0090] 2. Micro-quantitative magnetic susceptibility analysis: Extract magnetic susceptibility information from the reconstructed image, accurately separate the paramagnetic and diamagnetic susceptibility within the subvoxel from multiple directions, and perform quantitative analysis of the magnetic susceptibility.

[0091] Module 3 is system optimization and upgrade services: establish a healthy control data set to improve the accuracy and reliability of the imaging system, and apply the system in clinical research, such as in the fields of brain development and neurodegenerative diseases; continuously optimize and upgrade the imaging system based on clinical feedback and research results to improve its performance and applicability; update the software on the workstation to integrate the latest image processing technology.

[0092] The following is an explanation of the micro-quantitative magnetic sensitive imaging method based on ultra-fast scanning provided by the present invention from the perspective of a micro-quantitative magnetic sensitive imaging device based on ultra-fast scanning. The micro-quantitative magnetic sensitive imaging device based on ultra-fast scanning can be a server or a service unit in a server, without specific limitation.

[0093] See also Figure 2 , Figure 2 A schematic flow chart of a micro-quantitative magnetic susceptibility imaging method based on ultra-fast scanning provided by an embodiment of the present invention, the micro-quantitative magnetic susceptibility imaging method based on ultra-fast scanning comprises:

[0094] 201. Collect multiple two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images of the target brain.

[0095] In this embodiment, the micro-quantitative magnetic susceptibility imaging device based on ultra-fast scanning can collect multiple two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images of the target brain. Specifically, the micro-quantitative magnetic susceptibility imaging device based on ultra-fast scanning can first determine the sagittal, transverse and coronal positions corresponding to the target brain; and collect images of the target brain based on the sagittal, transverse and coronal positions to obtain multiple two-dimensional multi-band echo planar images.

[0096] That is, the micro-quantitative magnetically sensitive imaging device based on ultra-fast scanning collects two-dimensional multi-band echo planar imaging in the sagittal, transverse, and coronal planes, and also collects three-dimensional gradient echo scanning for distortion correction of echo planar imaging, thereby obtaining multiple slice images of the brain in a shorter time.

[0097] It should be noted that the specific scanning parameters of the acquisition device for the ultrafast scanning micro-quantitative magnetic sensitive imaging device for acquiring multiple two-dimensional multi-band echo planar imaging include: TE = 30ms, TR = 4000ms, in-plane resolution = 1.0×1.0mm, layer thickness = 2.5mm, 20% slice interval, matrix 224×224×74, parallel imaging technology acceleration factor R = 2, flip angle 2°, bandwidth of 1300Hz per pixel, and fat saturation, the net acquisition time is about 13s. Low-resolution three-dimensional gradient echo scanning is acquired for distortion correction: using sagittal position, TE = {1.5, 4}ms, TR = 5ms, resolution = 3.5×3.5×3.5mm, matrix 64×64×64, flip angle 5°, parallel imaging technology acceleration factor R = 2, and scanning time is about 5s.

[0098] 202. Perform distortion correction on the first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging.

[0099] In this embodiment, after acquiring multiple two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images, the ultra-fast scanning based micro-quantitative magnetic sensitive imaging device can perform distortion correction on the first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging, and the first two-dimensional multi-band echo planar imaging is any one of the multiple two-dimensional multi-band echo planar imaging.

[0100] In one embodiment, the ultrafast scanning-based micro-quantitative magnetically sensitive imaging device performs distortion correction on a first two-dimensional multi-band echo planar imaging based on a three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging, including:

[0101] determining a phase difference image based on two images with different echo times selected from the three-dimensional gradient echo scanning image;

[0102] estimating the distortion field based on the phase difference image;

[0103] adjusting the correction strength according to the degree of distortion and quality of the two-dimensional multi-band echo planar image;

[0104] The target distorted image is corrected based on the adjusted correction intensity and the distortion field to eliminate the geometric distortion caused by the magnetic field inhomogeneity, thereby obtaining a second two-dimensional multi-band echo planar imaging.

[0105] In this embodiment, the ultrafast scanning-based micro-quantitative magnetic sensitive imaging device can use the FUGUE (FSL's Unwarping GUI) tool in FSL (FMRIB Software Library) to perform distortion correction on the first and second multi-band echo planar imaging according to the field map method. The specific distortion correction steps include:

[0106] 1. Prepare data: The field map selects two images with different echo times to calculate the phase difference image;

[0107] 2. Estimation of distortion field: Use the FUGUE tool to automatically estimate the distortion field by inputting the data of the phase difference image;

[0108] 3. Set correction parameters: perform correction along the phase encoding direction and adjust the correction intensity according to the degree of distortion and quality of the image to be corrected;

[0109] 4. Perform correction: After setting the correction parameters, FUGUE will use the estimated distortion field to correct the distorted image. During the correction process, the image will be adjusted pixel by pixel to eliminate the geometric distortion caused by the magnetic field inhomogeneity, and then the second two-dimensional multi-band echo planar imaging will be obtained. It can be understood that after obtaining the corrected image, FUGUE will output the corrected image for further image analysis.

[0110] 203. Nonlinearly register the second two-dimensional multi-band echo planar imaging into the coordinate space of the high-resolution image to obtain a target registered image.

[0111] In this embodiment, the micro-quantitative magnetic sensitive imaging device based on ultra-fast scanning can use the MATLAB toolbox Volgenmodel to nonlinearly align the original low-resolution image (i.e., the second two-dimensional multi-band echo planar imaging) to the coordinate space of the high-resolution image to obtain a target registered image, thereby improving the clarity and usability of the image. The steps of nonlinear registration are as follows: 1. Set the registration parameters: including the registered transformation model (deformation field), the number of iterations (iterations are reduced from 20 times per stage with the maximum step length to 5 times per stage with the minimum step length), etc., and remove the image background field; 2. Perform nonlinear registration: Use the NlpFit function to perform nonlinear registration so that the low-resolution image is aligned with the high-resolution image as much as possible, thereby obtaining the target registered image.

[0112] 204. Perform upsampling processing on the target registration image to obtain a first high-resolution image.

[0113] In this embodiment, after the nonlinear registration of the second two-dimensional multi-band echo planar imaging is completed by the ultra-fast scanning micro-quantitative magnetic sensitive imaging device, the resolution of the low-resolution image is improved by the sinc interpolation method to match the resolution of the high-resolution image; Volgenmodel will output the registered and up-sampled image, and the original low-resolution image is now spatially aligned with the high-resolution image and has the same resolution, which can be used for further fine structure analysis.

[0114] 205. Process the first high-resolution image based on a pre-constructed iterative algorithm model of magnetic susceptibility separation to determine a second high-resolution image.

[0115] In this embodiment, after obtaining a first high-resolution image, the micro-quantitative magnetically sensitive imaging device based on ultra-fast scanning can process the first high-resolution image based on a pre-constructed iterative algorithm model of magnetic susceptibility separation to determine a second high-resolution image, which includes the magnetization distribution of paramagnetic materials and the magnetization distribution of diamagnetic materials.

[0116] In one embodiment, the first high-resolution image is processed based on a pre-built iterative algorithm model of magnetic susceptibility separation to determine the second high-resolution image, including:

[0117] Step 1: estimating the magnetic susceptibility distribution corresponding to the first high-resolution image according to the phase data of the first high-resolution image;

[0118] Step 2, initializing the magnetic susceptibility distribution;

[0119] Step 3, decomposing the phase data into the first magnetic susceptibility of the paramagnetic material and the second magnetic susceptibility of the diamagnetic material;

[0120] Step 4, updating the initialized magnetic susceptibility distribution according to the first magnetic susceptibility and the second magnetic susceptibility;

[0121] Step 5: iteratively execute steps 3 and 4 based on the updated magnetic susceptibility distribution, and adjust the weights during the iterative execution by multi-scale iterative reweighted least squares method until a preset iteration termination condition is reached to obtain a second high-resolution image.

[0122] In this embodiment, the micro-quantitative magnetically sensitive imaging device based on ultra-fast scanning can first determine the phase data of the first high-resolution image by the following formula:

[0123] φ=φ0+k·d;

[0124] Wherein, φ is the phase data of the first high-resolution image, φ0 is the background phase corresponding to the first high-resolution image, k is the magnetic susceptibility distribution, and d is the distance of the local field corresponding to the first high-resolution image;

[0125] Afterwards, the magnetic susceptibility distribution is determined by the following formula:

[0126]

[0127] Where k is the magnetic susceptibility distribution, B curl is the eddy current field corresponding to the first high-resolution image, d is the distance of the local field corresponding to the first high-resolution image, λ is the regularization parameter, B curl =B0-B macro , B0 is the background field corresponding to the first high-resolution image, B macro is the macroscopic magnetic field of the background field;

[0128] The determined magnetic susceptibility distribution is initialized, and the phase data is decomposed into the first magnetic susceptibility of paramagnetic materials and the second magnetic susceptibility of diamagnetic materials by the following formula:

[0129] φ=φ0+k p ·dk d ·d

[0130] Among them, k p is the first magnetic susceptibility, k d is the second magnetic susceptibility.

[0131] Afterwards, the initialized magnetic susceptibility distribution is updated according to the first magnetic susceptibility and the second magnetic susceptibility by the following formula:

[0132]

[0133] Finally, the above steps are iteratively performed based on the updated magnetic susceptibility distribution, and the weights are adjusted during the iterative execution using the multi-scale iterative reweighted least squares method until a preset iteration termination condition is reached to obtain a second high-resolution image.

[0134] 206. Process the local field in the second high-resolution image using a voxel-specific attenuation kernel to obtain a third high-resolution image.

[0135] In this embodiment, after obtaining the second high-resolution image including the magnetic susceptibility distribution of the paramagnetic material and the magnetic susceptibility distribution of the diamagnetic material, the micro-quantitative magnetic sensitive imaging device based on ultra-fast scanning can process the local field in the second high-resolution image by using a voxel-specific attenuation kernel to obtain a third high-resolution image. Specifically, the local field in the second high-resolution image can be processed by the following formula to obtain the third high-resolution image:

[0136]

[0137] Where L(x) is the local field at position x in the second high-resolution image, K(x,y) is the voxel-specific attenuation kernel at position x, B0(y) is the background field at position y in the second high-resolution image, Ω is the imaging volume corresponding to the second high-resolution image, and dy is the distance of the local field at position y.

[0138] 207. Deconvolution is performed on the third high-resolution image to obtain micro-quantified magnetic susceptibility imaging corresponding to the target brain.

[0139] In this embodiment, after the ultra-fast scanning-based micro-quantitative magnetic susceptibility imaging device uses a voxel-specific attenuation kernel to improve the accuracy of the second high-resolution image to obtain a third high-resolution image, the third high-resolution image can be deconvolved to obtain a micro-quantitative magnetic susceptibility imaging corresponding to the target brain. Specifically, the ultra-fast scanning-based micro-quantitative magnetic susceptibility imaging device can perform a deconvolution process using the deconvlucy function in MATLAB to correct image blur and improve image resolution, and use the super-resolution software Super-Resolution Convolutional Neural Network (SRCNN) to further improve the image resolution to obtain micro-quantitative magnetic susceptibility imaging.

[0140] It should be noted that after obtaining micro-quantitative magnetic susceptibility imaging, image segmentation technology can be used to analyze sub-regions in the image, and by accurately obtaining the distribution and ratio information of paramagnetic and diamagnetic susceptibility in each voxel, microstructural tissue compartments with higher sensitivity and specificity with different susceptibility characteristics can be estimated. Such analysis can comprehensively and accurately reveal the microstructural characteristics of the tissue and realize quantitative analysis of the microstructure at the subvoxel level. Compared with the existing voxel-level analysis, this method makes the results of quantitative analysis more accurate and reliable.

[0141] In summary, it can be seen that in the embodiment provided by the present invention, the two-dimensional multi-band echo planar imaging is corrected by the collected three-dimensional gradient echo scanning image, and the corrected image is subjected to nonlinear processing and up-sampling, and the magnetization distribution of the paramagnetic material and the diamagnetic material is determined for the up-sampled image, and the local field processing and deconvolution processing are performed by the voxel-specific attenuation kernel, thereby obtaining the micro-quantitative magnetic susceptibility imaging. Therefore, through reconstruction technology and image processing algorithms, the resolution and scanning efficiency of QSM are improved, and the magnetic susceptibility distribution of the paramagnetic material and the magnetic susceptibility distribution of the diamagnetic material in the subvoxel can be distinguished, thereby overcoming the limitations of the traditional high-resolution QSM method, and obtaining micro-quantitative magnetic susceptibility imaging with high signal-to-noise ratio and ultra-high resolution.

[0142] The above describes the embodiment of the present invention from the perspective of a micro-quantitative magnetic sensitivity imaging method based on ultra-fast scanning. The following describes the embodiment of the present invention from the perspective of a micro-quantitative magnetic sensitivity imaging device based on ultra-fast scanning.

[0143] See also Figure 3 , a virtual structural diagram of a micro-quantitative magnetic sensitive imaging device based on ultra-fast scanning in an embodiment of the present invention, the micro-quantitative magnetic sensitive imaging device based on ultra-fast scanning 300 comprises:

[0144] An acquisition unit 301 is used to acquire multiple two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images of the target brain;

[0145] A distortion correction unit 302 is used to perform distortion correction on a first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging, wherein the first two-dimensional multi-band echo planar imaging is any one of the multiple two-dimensional multi-band echo planar imaging;

[0146] A nonlinear registration unit 303, configured to nonlinearly register the second two-dimensional multi-band echo planar imaging into the coordinate space of the high-resolution image to obtain a target registered image;

[0147] An upsampling unit 304 is used to perform upsampling processing on the target registration image to obtain a first high-resolution image;

[0148] A magnetic susceptibility separation unit 305 is used to process the first high-resolution image based on a pre-constructed iterative algorithm model of magnetic susceptibility separation to determine a second high-resolution image, wherein the second high-resolution image includes a magnetization distribution of the paramagnetic substance and a magnetization distribution of the diamagnetic substance;

[0149] A local field processing unit 306, configured to process the local field in the second high-resolution image by using a voxel-specific attenuation kernel to obtain a third high-resolution image;

[0150] The convolution processing unit 307 is used to perform deconvolution processing on the third high-resolution image to obtain the micro-quantified magnetic susceptibility imaging corresponding to the target brain.

[0151] In a possible design, the distortion correction unit 302 is specifically configured to:

[0152] Determine a phase difference image based on two images with different echo times selected from the three-dimensional gradient echo scanning image;

[0153] estimating a distortion field according to the phase difference image;

[0154] adjusting the correction strength according to the degree of distortion and quality of the two-dimensional multi-band echo planar image;

[0155] The target distorted image is corrected based on the adjusted correction intensity and the distortion field to eliminate geometric distortion caused by magnetic field inhomogeneity, thereby obtaining the second two-dimensional multi-band echo planar imaging.

[0156] In a possible design, the magnetic susceptibility separation unit 305 is specifically used for:

[0157] Step 1: estimating the magnetic susceptibility distribution corresponding to the first high-resolution image according to the phase data of the first high-resolution image;

[0158] Step 2, initializing the magnetic susceptibility distribution;

[0159] Step 3, decomposing the phase data into a first magnetic susceptibility of the paramagnetic material and a second magnetic susceptibility of the diamagnetic material;

[0160] Step 4, updating the initialized magnetic susceptibility distribution according to the first magnetic susceptibility and the second magnetic susceptibility;

[0161] Step 5: iteratively execute steps 3 and 4 based on the updated magnetic susceptibility distribution, and adjust the weights during the iterative execution by multi-scale iterative reweighted least squares method until a preset iteration termination condition is reached to obtain the second high-resolution image.

[0162] In a possible design, the magnetic susceptibility separation unit 305 is further specifically used for:

[0163] The magnetic susceptibility distribution is determined by the following formula:

[0164]

[0165] Where k is the magnetic susceptibility distribution, B curl is the eddy current field corresponding to the first high-resolution image, d is the distance of the local field corresponding to the first high-resolution image, λ is the regularization parameter, B curl =B0-B macro , B0 is the background field corresponding to the first high-resolution image, B macro is the macroscopic magnetic field of the background field;

[0166] In a possible design, the magnetic susceptibility separation unit 305 is further specifically used for:

[0167] The magnetic susceptibility distribution after initialization is updated by the following formula:

[0168]

[0169] φ=φ0+k p ·dk d ·d, φ0 is the background phase corresponding to the first high-resolution image.

[0170] In a possible design, the local field processing unit 306 is specifically used for:

[0171] The local field in the second high-resolution image is processed by the following formula to obtain a third high-resolution image:

[0172]

[0173] Wherein, L(x) is the local field at position x in the second high-resolution image, K(x,y) is the voxel-specific attenuation kernel at the position x, B0(y) is the background field at position y in the second high-resolution image, Ω is the imaging volume corresponding to the second high-resolution image, and dy is the distance of the local field at the position y.

[0174] In a possible design, the collection unit 301 is specifically used for:

[0175] Determining the sagittal, transverse and coronal positions corresponding to the target brain;

[0176] The imaging of the target brain is acquired based on the sagittal position, the transverse position, and the coronal position to obtain the multiple two-dimensional multi-band echo planar images.

[0177] above Figure 3 The ultra-fast scanning micro-magnetic sensitive imaging device in the embodiment of the present invention is described from the perspective of modular functional entities. The ultra-fast scanning micro-magnetic sensitive imaging device in the embodiment of the present invention is described in detail from the perspective of hardware processing. Figure 4 , a schematic diagram of an embodiment of a micro-quantitative magnetic sensitive imaging device 400 based on ultra-fast scanning in an embodiment of the present invention, the micro-quantitative magnetic sensitive imaging device 400 based on ultra-fast scanning comprises:

[0178] An input device 401, an output device 402, a processor 403 and a memory 404 (the number of the processor 403 can be one or more, Figure 4 In some embodiments of the present invention, the input device 401, the output device 402, the processor 403 and the memory 404 may be connected via a communication bus or other means, wherein: Figure 4 The communication bus connection is taken as an example.

[0179] Wherein, by calling the operation instruction stored in the memory 404, the processor 403 is used to perform the following steps:

[0180] Acquire multiple two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images of the target brain;

[0181] Performing distortion correction on a first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging, wherein the first two-dimensional multi-band echo planar imaging is any one of the multiple two-dimensional multi-band echo planar imaging;

[0182] nonlinearly registering the second two-dimensional multi-band echo planar imaging into the coordinate space of the high-resolution image to obtain a target registered image;

[0183] Performing upsampling processing on the target registration image to obtain a first high-resolution image;

[0184] Processing the first high-resolution image based on a pre-constructed iterative algorithm model of magnetic susceptibility separation to determine a second high-resolution image, wherein the second high-resolution image includes a magnetization distribution of the paramagnetic substance and a magnetization distribution of the diamagnetic substance;

[0185] Processing the local field in the second high-resolution image by a voxel-specific attenuation kernel to obtain a third high-resolution image;

[0186] The third high-resolution image is subjected to a deconvolution process to obtain a micro-quantified magnetic susceptibility imaging corresponding to the target brain.

[0187] By calling the operation instructions stored in the memory 404, the processor 403 is also used to execute Figure 2 Any method in the corresponding embodiment.

[0188] See also Figure 5 , Figure 5 A schematic diagram of an electronic device according to an embodiment of the present invention.

[0189] like Figure 5 As shown, an embodiment of the present invention provides an electronic device, including a memory 510, a processor 520, and a computer program 511 stored in the memory 510 and executable on the processor 520. When the processor 520 executes the computer program 511, the following steps are implemented:

[0190] Acquire multiple two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images of the target brain;

[0191] Performing distortion correction on a first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging, wherein the first two-dimensional multi-band echo planar imaging is any one of the multiple two-dimensional multi-band echo planar imaging;

[0192] nonlinearly registering the second two-dimensional multi-band echo planar imaging into the coordinate space of the high-resolution image to obtain a target registered image;

[0193] Performing upsampling processing on the target registration image to obtain a first high-resolution image;

[0194] Processing the first high-resolution image based on a pre-constructed iterative algorithm model of magnetic susceptibility separation to determine a second high-resolution image, wherein the second high-resolution image includes a magnetization distribution of the paramagnetic substance and a magnetization distribution of the diamagnetic substance;

[0195] Processing the local field in the second high-resolution image by a voxel-specific attenuation kernel to obtain a third high-resolution image;

[0196] The third high-resolution image is subjected to a deconvolution process to obtain a micro-quantified magnetic susceptibility imaging corresponding to the target brain.

[0197] In a specific implementation process, when the processor 520 executes the computer program 511, it can achieve Figure 2 Any implementation manner in the corresponding embodiments.

[0198] Since the electronic device introduced in this embodiment is a device used to implement a micro-quantitative magnetically sensitive imaging device based on ultra-fast scanning in the embodiment of the present invention, based on the method introduced in the embodiment of the present invention, the technical personnel in this field can understand the specific implementation of the electronic device of this embodiment and its various variations. Therefore, how the electronic device implements the method in the embodiment of the present invention is not introduced in detail here. As long as the equipment used by the technical personnel in this field to implement the method in the embodiment of the present invention belongs to the scope of protection of the present invention.

[0199] See also Figure 6 , Figure 6 A schematic diagram of an embodiment of a computer-readable storage medium provided in an embodiment of the present invention.

[0200] like Figure 6 As shown, the embodiment of the present invention further provides a computer-readable storage medium 600, on which a computer program 611 is stored. When the computer program 611 is executed by a processor, the following steps are implemented:

[0201] Acquire multiple two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images of the target brain;

[0202] Performing distortion correction on a first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging, wherein the first two-dimensional multi-band echo planar imaging is any one of the multiple two-dimensional multi-band echo planar imaging;

[0203] nonlinearly registering the second two-dimensional multi-band echo planar imaging into the coordinate space of the high-resolution image to obtain a target registered image;

[0204] Performing upsampling processing on the target registration image to obtain a first high-resolution image;

[0205] Processing the first high-resolution image based on a pre-constructed iterative algorithm model of magnetic susceptibility separation to determine a second high-resolution image, wherein the second high-resolution image includes a magnetization distribution of the paramagnetic substance and a magnetization distribution of the diamagnetic substance;

[0206] Processing the local field in the second high-resolution image by a voxel-specific attenuation kernel to obtain a third high-resolution image;

[0207] The third high-resolution image is subjected to a deconvolution process to obtain a micro-quantified magnetic susceptibility imaging corresponding to the target brain.

[0208] In the specific implementation process, the computer program 611 is executed by the processor to achieve Figure 2 Any implementation manner in the corresponding embodiments.

[0209] It should be noted that in the above embodiments, the description of each embodiment has its own emphasis, and for parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0210] The embodiment of the present invention also provides a computer program product, which includes computer software instructions. When the computer software instructions are executed on a processing device, the processing device executes the following Figure 1 The process in the corresponding embodiment.

[0211] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A micro-quantitative magnetic sensitivity imaging method based on ultra-fast scanning, characterized in that: include: Acquire multiple two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images of the target brain; Performing distortion correction on a first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging, wherein the first two-dimensional multi-band echo planar imaging is any one of the multiple two-dimensional multi-band echo planar imaging; nonlinearly registering the second two-dimensional multi-band echo planar imaging into the coordinate space of the high-resolution image to obtain a target registered image; Performing upsampling processing on the target registration image to obtain a first high-resolution image; Processing the first high-resolution image based on a pre-constructed iterative algorithm model of magnetic susceptibility separation to determine a second high-resolution image, wherein the second high-resolution image includes a magnetization distribution of the paramagnetic substance and a magnetization distribution of the diamagnetic substance; Processing the local field in the second high-resolution image by a voxel-specific attenuation kernel to obtain a third high-resolution image; The third high-resolution image is subjected to a deconvolution process to obtain a micro-quantified magnetic susceptibility imaging corresponding to the target brain.

2. The method according to claim 1, characterized in that The step of performing distortion correction on the first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging comprises: Determine a phase difference image based on two images with different echo times selected from the three-dimensional gradient echo scanning image; estimating a distortion field according to the phase difference image; adjusting the correction strength according to the degree of distortion and quality of the two-dimensional multi-band echo planar imaging; The target distorted image is corrected based on the adjusted correction intensity and the distortion field to eliminate the geometric distortion caused by magnetic field inhomogeneity, thereby obtaining the second two-dimensional multi-band echo planar imaging.

3. The method according to claim 1, characterized in that The iterative algorithm model based on the pre-built magnetic susceptibility separation processes the first high-resolution image to determine the second high-resolution image, comprising: Step 1: estimating the magnetic susceptibility distribution corresponding to the first high-resolution image according to the phase data of the first high-resolution image; Step 2, initializing the magnetic susceptibility distribution; Step 3, decomposing the phase data into a first magnetic susceptibility of the paramagnetic material and a second magnetic susceptibility of the diamagnetic material; Step 4, updating the initialized magnetic susceptibility distribution according to the first magnetic susceptibility and the second magnetic susceptibility; Step 5: iteratively execute steps 3 and 4 based on the updated magnetic susceptibility distribution, and adjust the weights during the iterative execution by multi-scale iterative reweighted least squares method until a preset iteration termination condition is reached to obtain the second high-resolution image.

4. The method according to claim 3, characterized in that The estimating the magnetic susceptibility distribution corresponding to the first high-resolution image according to the phase data of the first high-resolution image comprises: The magnetic susceptibility distribution is determined by the following formula: Where k is the magnetic susceptibility distribution, B curl is the eddy current field corresponding to the first high-resolution image, d is the distance of the local field corresponding to the first high-resolution image, λ is the regularization parameter, B curl =B0-B macro , B0 is the background field corresponding to the first high-resolution image, B macro is the macroscopic magnetic field of the background field.

5. The method according to claim 3, characterized in that: The updating of the initialized magnetic susceptibility distribution according to the first magnetic susceptibility and the second magnetic susceptibility comprises: The magnetic susceptibility distribution after initialization is updated by the following formula: Among them, k p is the first magnetic susceptibility, k d is the second magnetic susceptibility, φ is the phase data, φ=φ0+k p ·dk d ·d, φ0 is the background phase corresponding to the first high-resolution image.

6. The method according to any one of claims 1 to 5, characterized in that The processing of the local field in the second high-resolution image by using a voxel-specific attenuation kernel to obtain a third high-resolution image comprises: The local field in the second high-resolution image is processed by the following formula to obtain a third high-resolution image: Wherein, L(x) is the local field at position x in the second high-resolution image, K(x,y) is the voxel-specific attenuation kernel at the position x, B0(y) is the background field at position y in the second high-resolution image, Ω is the imaging volume corresponding to the second high-resolution image, and dy is the distance of the local field at the position y.

7. The method according to any one of claims 1 to 5, characterized in that The acquiring of a plurality of two-dimensional multi-band echo planar images of the target brain comprises: Determining the sagittal, transverse and coronal positions corresponding to the target brain; The imaging of the target brain is acquired based on the sagittal position, the transverse position, and the coronal position to obtain the multiple two-dimensional multi-band echo planar imaging.

8. A micro-quantitative magnetic sensitive imaging device based on ultra-fast scanning, characterized in that: include: An acquisition unit, used for acquiring a plurality of two-dimensional multi-band echo planar imaging and three-dimensional gradient echo scanning images of the target brain; a distortion correction unit, configured to perform distortion correction on a first two-dimensional multi-band echo planar imaging based on the three-dimensional gradient echo scanning image to obtain a second two-dimensional multi-band echo planar imaging, wherein the first two-dimensional multi-band echo planar imaging is any one of the multiple two-dimensional multi-band echo planar imaging; A nonlinear registration unit, used for nonlinearly registering the second two-dimensional multi-band echo planar imaging into the coordinate space of the high-resolution image to obtain a target registered image; An upsampling unit, configured to perform upsampling processing on the target registration image to obtain a first high-resolution image; A magnetic susceptibility separation unit, configured to process the first high-resolution image based on a pre-constructed iterative algorithm model of magnetic susceptibility separation to determine a second high-resolution image, wherein the second high-resolution image includes a magnetization distribution of the paramagnetic substance and a magnetization distribution of the diamagnetic substance; a local field processing unit, configured to process the local field in the second high-resolution image by using a voxel-specific attenuation kernel to obtain a third high-resolution image; A convolution processing unit is used to perform deconvolution processing on the third high-resolution image to obtain micro-quantified magnetic susceptibility imaging corresponding to the target brain.

9. An electronic device, characterized in that: include: A memory and a processor, wherein the processor is used to implement the ultra-fast scanning based micro-quantitative magnetic susceptibility imaging method as described in any one of claims 1 to 5 when executing the computer management program stored in the memory.

10. A computer-readable storage medium having a computer management program stored thereon, characterized in that: When the computer management program is executed by the processor, the micro-quantitative magnetic susceptibility imaging method based on ultra-fast scanning as described in any one of claims 1 to 5 is implemented.

Images