Magnetic resonance chemical exchange saturation transfer imaging method, system, and apparatus

Abstract

This application discloses a magnetic resonance chemical exchange saturation transfer imaging method, system, device, and storage medium. The method includes: applying a radio frequency saturation pulse for a first preset time to a region to be detected; applying a radio frequency echo pulse to the region to be detected and acquiring several gradient echo signals generated after activation by the radio frequency echo pulse; and using radial sampling to read the gradient echo signals along a preset direction to generate a magnetic resonance image. Through this method, this application effectively shortens the signal acquisition time by using gradient echo readings, effectively suppresses motion artifacts by using radial acquisition, and applies post-processing methods such as fitting to the acquired chemical exchange saturation transfer imaging spectral data to achieve water-lipid signal separation and extract and analyze the target signal.

Description

Technical Field

[0001] This application relates to the field of magnetic resonance CEST imaging technology, and in particular to a magnetic resonance chemical exchange saturation transfer imaging method, system, device, and storage medium. Background Technology

[0002] Research on the Chemical Exchange Saturation Transfer (CEST) imaging method began in 2000. Due to its novel magnetic resonance contrast mechanism, it has rapidly gained widespread attention, becoming a new and sensitive approach for studying macromolecular chemical exchange and chemical kinetics. Its principle is to selectively apply a radio frequency (RF) pulse signal at a specific resonance frequency to saturate the corresponding protons (e.g., ...). Figure 1 In pool B), under suitable conditions, these protons will react with surrounding water molecules (such as...). Figure 1 A chemical exchange occurs between the water molecules and pool A, resulting in the partial transfer of saturated water molecules to the water molecules. The strength of the CEST effect is reflected by detecting the decrease in the signal from the water molecules. Figure 1 The chemical exchange process that occurs during the application of a saturation pulse significantly amplifies the loss of proton signals, making CEST contrast more sensitive than direct observation of these protons using magnetic resonance spectroscopy. Compared to other magnetic resonance contrast mechanisms, such as T1, T2, and diffusion-weighted imaging, CEST can explore molecular targets containing exchangeable protons at specific frequencies, making it highly sensitive to metabolic substances and the microenvironment within organisms, thus representing a unique molecular imaging approach. Since chemical exchange is closely related to the physiological environment of biological tissues, CEST can be used to image multiple important physiological parameters, such as intracellular and extracellular acid-base balance and metabolic characteristics, playing a crucial role in the detection and assessment of various diseases, including metabolic disorders and tissue ischemia.

[0003] However, during abdominal CEST imaging, human movement (including breathing, involuntary movement, etc.) can introduce motion artifacts into CEST images. Especially during abdominal scanning, respiratory movement can severely disrupt the consistency of K-space acquisition data, affect the quality of magnetic resonance image reconstruction, and cause errors in CEST signal quantification. In some scenarios, the fat signal is too strong, which seriously interferes with the CEST results. Summary of the Invention

[0004] This application provides a magnetic resonance chemical exchange saturation transfer imaging method, system, device, and storage medium to solve the problems of traditional magnetic resonance imaging methods that easily introduce motion artifacts, affecting the quality of magnetic resonance image reconstruction and fat signal interference with CEST signal quantification.

[0005] To solve the above-mentioned technical problems, one technical solution adopted in this application is: to provide a magnetic resonance chemical exchange saturation transfer imaging method, the magnetic resonance chemical exchange saturation transfer imaging method comprising:

[0006] A radio frequency saturation pulse lasting for a first preset time is applied to the area to be detected;

[0007] A radio frequency echo pulse is applied to the region to be detected, and several gradient echo signals generated after the radio frequency echo pulse is activated are acquired.

[0008] Using radial sampling, several gradient echo signals are read along a preset direction to generate a magnetic resonance image.

[0009] According to one embodiment provided in this application, the radial sampling method has 151 radial sampling spokes, the first preset time is 50ms, and the gradient echo beams for each radial sampling are 6.

[0010] According to one embodiment provided in this application, the signal attenuation model of the plurality of gradient echo signals is as follows:

[0011]

[0012] Among them, S n Indicates echo time TW n The echo signal strength at time n = 1, 2, ..., N ≥ 3, where N represents the number of echoes; ρ ω Indicates water signal strength; ρ f This represents the signal intensity of fat; P represents the number of peak components in fat, and the relative amplitude of each component is α. p ,satisfy Indicates its corresponding chemical shift; f B =γΔB is the local magnetization; f F,p This represents the chemical shift of the p-th fat peak component relative to water.

[0013] According to one embodiment provided in this application, the magnetic resonance chemical exchange saturation transfer imaging method further includes:

[0014] Acquire several magnetic resonance images of several gradient echo signals;

[0015] Using a preset water-fat separation algorithm, magnetic resonance water images and magnetic resonance fat images are separated from the plurality of magnetic resonance images;

[0016] The magnetic resonance water image is used for signal quantization, and concentration information is obtained based on the signal quantization result.

[0017] According to one embodiment provided in this application, the preset water-lipid separation algorithm is a self-testing field map estimation algorithm based on multi-resolution local growth.

[0018] According to one embodiment provided in this application, before signal quantization using the magnetic resonance water image, the magnetic resonance chemical exchange saturation transfer imaging method further includes:

[0019] In response to a user instruction, the region of interest corresponding to the user instruction is selected in the magnetic resonance water image.

[0020] According to one embodiment provided in this application, the signal quantization using the magnetic resonance water image includes:

[0021] Based on the magnetic resonance water image, obtain the Z spectrum of the pixels in the region of interest;

[0022] The Z-spectrum was post-processed for correction, symmetry analysis, and multi-pool Lorentz fitting.

[0023] To solve the above-mentioned technical problems, another technical solution adopted in this application is: to provide a magnetic resonance chemical exchange saturation transfer imaging system, the magnetic resonance chemical exchange saturation transfer imaging system comprising: a pulse module, an echo module, and an imaging module; wherein,

[0024] The pulse module is used to apply a radio frequency saturation pulse that lasts for a first preset time to the area to be detected;

[0025] The echo module is used to apply a radio frequency echo pulse to the area to be detected and to acquire several gradient echo signals generated after the radio frequency echo pulse is activated.

[0026] The imaging module is used to read the plurality of gradient echo signals along a preset direction using a radial sampling method to generate a magnetic resonance image.

[0027] To solve the above-mentioned technical problems, another technical solution adopted in this application is: to provide a magnetic resonance chemical exchange saturation transfer imaging device, the magnetic resonance chemical exchange saturation transfer imaging device including a memory and a processor coupled to the memory;

[0028] The memory is used to store program data, and the processor is used to execute the program data to implement the magnetic resonance chemical exchange saturation transfer imaging method as described above.

[0029] To solve the above-mentioned technical problems, another technical solution adopted in this application is to provide a computer storage medium for storing program data, which, when executed by a computer, is used to implement the magnetic resonance chemical exchange saturation transfer imaging method as described above.

[0030] This application provides a magnetic resonance chemical exchange saturation transfer imaging method, system, device, and storage medium. The method includes: applying a radio frequency saturation pulse for a first preset time to a region to be detected; applying a radio frequency echo pulse to the region to be detected and acquiring several gradient echo signals generated after activation by the radio frequency echo pulse; and using radial sampling to read the gradient echo signals along a preset direction to generate a magnetic resonance image. Through this method, this application effectively shortens the signal acquisition time by using gradient echo readings, effectively suppresses motion artifacts by using radial acquisition, and applies post-processing methods such as fitting to the acquired chemical exchange saturation transfer imaging spectral data to achieve water-lipid signal separation, effectively suppressing fat signal interference, and extracting and analyzing the target signal. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application, 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 this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0032] Figure 1 This is a timing map of the mGRE-CEST magnetic resonance sequence provided in this application;

[0033] Figure 2 This is a schematic flowchart of an embodiment of the magnetic resonance chemical exchange saturation transfer imaging method provided in this application;

[0034] Figure 3 This is a schematic diagram of sequential radial K-space sampling provided in this application;

[0035] Figure 4 This is a schematic flowchart of another embodiment of the magnetic resonance chemical exchange saturation transfer imaging method provided in this application;

[0036] Figure 5 This is a schematic diagram comparing the Z-spectrum before and after water-lipid separation provided in this application;

[0037] Figure 6 This is a comparison chart of mGRE-CEST and FSE-CEST provided in this application;

[0038] Figure 7 This is a schematic diagram of the structure of an embodiment of the magnetic resonance chemical exchange saturation transfer imaging system provided in this application;

[0039] Figure 8 This is a schematic diagram of the structure of an embodiment of the magnetic resonance chemical exchange saturation transfer imaging device provided in this application;

[0040] Figure 9 This is a schematic diagram of the structure of an embodiment of the computer storage medium provided in this application. Detailed Implementation

[0041] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0042] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0043] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0044] CEST sequences typically consist of a saturation module and a acquisition module. A saturation pulse of a certain duration is applied to fully saturate the solute molecules, causing a chemical exchange between hydrogen protons in the free water and solute. This transfers saturation from the solute to the free water, and over time, this accumulation leads to the attenuation of the free water signal. By detecting changes in the water signal, information about the substance is indirectly reflected.

[0045] Human movement introduces motion artifacts into CEST images, especially during abdominal scans. Respiratory movements can severely disrupt the consistency of K-space data acquisition, affecting the quality of magnetic resonance image reconstruction and causing errors in CEST signal quantification.

[0046] Abdominal respiratory movements and fat deposition interfere with CEST MRI images, and current techniques are mostly suitable for brain and limb scans, not abdominal scans. During FSE sequence image acquisition, flow and motion artifacts increase. Furthermore, when acquiring images of the liver, uncontrollable abdominal breathing leads to motion artifacts, which can cause errors in CEST signal quantization. In addition, FSE sequences enhance adipose tissue signals, and the presence of fat signals overlaps with CEST signals on the Z-spectrum, hindering accurate CEST signal quantization.

[0047] To address the shortcomings of existing technologies in abdominal scanning, this application designs a novel CEST sequence (mGRE-CEST), specifically as follows: Figure 1 As shown, this sequence retains the advantages of radial acquisition and effectively suppresses motion artifacts.

[0048] To address this, this application provides a specific magnetic resonance chemical exchange saturation transfer imaging method. Please refer to [link / reference] for details. Figure 2 , Figure 2 This is a schematic flowchart of an embodiment of the magnetic resonance chemical exchange saturation transfer imaging method provided in this application.

[0049] like Figure 2 As shown, the magnetic resonance chemical exchange saturation transfer imaging method of this application embodiment may specifically include the following steps:

[0050] Step S11: Apply a radio frequency saturation pulse that lasts for a first preset time to the area to be detected.

[0051] Step S12: Apply radio frequency echo pulses to the area to be detected and acquire several gradient echo signals generated after the radio frequency echo pulses are activated.

[0052] In the embodiments of this application, the sequence diagram of the design sequence used is as follows: Figure 1 As shown, in the design of the saturation module, a Gaussian saturation pulse is first applied, lasting 50ms. After sufficient pre-saturation, a 90° RF pulse is applied. The RF pulse excitation generates several echoes, such as... Figure 1 The signal attenuation of the six echoes shown is as follows: The signal attenuation of several echoes decreases sequentially, and the signal attenuation model is illustrated by the following formula:

[0053]

[0054] Among them, S n Indicates echo time TE n The echo signal strength at time n = 1, 2, ..., N ≥ 3, where N represents the number of echoes; ρ ω Indicates water signal strength; ρ fThis represents the signal intensity of fat; P represents the number of peak components in fat, and the relative amplitude of each component is α. p ,satisfy Indicates its corresponding chemical shift; f B =γΔB is the local magnetization; f F,p This represents the chemical shift of the p-th fat peak component relative to water.

[0055] Where γ = 42.576 MHz / T is the gyromagnetic ratio of the hydrogen proton.

[0056] This step designs a novel CEST image acquisition sequence that uses gradient echo (GRE) readings. This acquisition method eliminates the need to repeatedly apply excitation pulses and can acquire multiple echoes after a single excitation pulse, effectively shortening the signal acquisition time.

[0057] Step S13: Using radial sampling, read several echo signals along a preset direction to generate a magnetic resonance image.

[0058] In this embodiment, the K-space sampling method used is sequential radial sampling, such as... Figure 3 As shown, in radial sampling, the "spokes" continuously cross the central region, causing oversampling of the K-space data at the center. Over-sampling of the central region of K-space leads to the averaging of artifacts, and the self-gating effect of radial sampling further enhances the resistance to motion artifacts. If the signal data at the center of K-space changes in the radially acquired data, the signal redundancy can be used to correct the influence of motion on the acquired data.

[0059] This application designs 151 radial sampling spokes and 6 gradient echoes per radial sample. Using these parameters ensures image quality and a short sampling time. In other embodiments, other numbers of radial sampling spokes and gradient echoes can be used, which will not be elaborated here.

[0060] The K-space sampling method used in this step is sequential radial filling, which can effectively suppress motion artifacts. In other embodiments, other sequential radial sampling methods can be designed, which will not be elaborated here.

[0061] In this embodiment, the magnetic resonance chemical exchange saturation transfer imaging method includes: applying a radio frequency saturation pulse lasting for a first preset time to the region to be detected; applying a radio frequency echo pulse to the region to be detected and acquiring a plurality of echo signals generated after the radio frequency echo pulse is activated; and reading the plurality of echo signals along a preset direction using a radial sampling method to generate a magnetic resonance image. Through the above method, this application effectively shortens the signal acquisition time by using gradient echo readings and effectively suppresses motion artifacts by using a sequential radial acquisition method.

[0062] Furthermore, the presence of fat deposition in the abdomen can cause quantization errors due to the overlap between the target CEST signal and the fat signal in the Z-spectrum. Therefore, this application incorporates a water-fat separation algorithm in image preprocessing to eliminate the interference of the fat signal on the quantization of the CEST signal.

[0063] Please refer to the details. Figure 4 , Figure 4 This is a schematic flowchart of another embodiment of the magnetic resonance chemical exchange saturation transfer imaging method provided in this application.

[0064] like Figure 4 As shown, the magnetic resonance chemical exchange saturation transfer imaging method of this application embodiment may specifically include the following steps:

[0065] Step S14: Acquire several magnetic resonance images of several gradient echo signals.

[0066] Step S15: Using a preset water-fat separation algorithm, separate the magnetic resonance water image and the magnetic resonance fat image from several magnetic resonance images.

[0067] In this embodiment, to effectively remove fat signals, a self-testing field map estimation algorithm based on multi-resolution local growth is used to achieve water-fat separation. This method can independently complete the selection of seed points and local growth, and uses a self-testing mechanism to merge field maps at different resolutions, ensuring the positiveness of the field map estimation values ​​of the seed points. This method can effectively solve the problem of water-fat separation caused by the ambiguity of water-fat separation.

[0068] The magnetic resonance imaging (MRI) image was calculated using a self-tested field map estimation algorithm based on multi-resolution local growth to obtain the correct field map. Combined with the following formula, the MRI water image and MRI fat image were then obtained:

[0069]

[0070] Where S = [S1, S2, ..., S N ] T A = [A1; A2; ...; A N ], I is an N×N matrix, W is a magnetic resonance water image, and F is a magnetic resonance fat image.

[0071] In other embodiments, other mature water-fat separation algorithms may also be used, which will not be listed here.

[0072] In this step, the CEST image is preprocessed using a water-fat separation algorithm. This algorithm divides the CEST image into a water map and a fat map, which can effectively remove fat signals from the image.

[0073] Step S16: Quantize the signal using magnetic resonance water images and obtain concentration information based on the signal quantization results.

[0074] In this embodiment, for the acquired magnetic resonance water image, the operator can select a region of interest on the image to automatically generate the average Z-spectrum of the pixels within that region. The Z-spectrum undergoes B0 offset correction and asymmetric analysis. The processed Z-spectrum exhibits a Lorentzian linear distribution.

[0075] To eliminate the DS effect (water saturation effect) and MT effect (magnetization transfer effect), the preprocessed Z-spectrum needs to be subjected to multi-pool Lorentz fitting. The expression for the Lorentz function is shown in the following formula:

[0076]

[0077] Where S(Δω) is the labeled frequency signal, a function of the water offset frequency (Δω), S0 is the signal strength without the applied saturation frequency, and A i ω i , σ i represents the amplitude, frequency shift, and line width of the i-th peak, respectively, and N represents the number of fitted peaks.

[0078] During signal quantization, the amplitude of the CEST signal in the target needs to be set to zero, and the Lorentz line shape is used to fit each drop position in the Z spectrum.

[0079] In this step, the multi-pool Lorentz fitting method can effectively remove the direct saturation (DS) and magnetization transfer (MT) effects, and the target signal can be quantized using this method.

[0080] In the phantom experiments, a phantom with a fat content of 20% was used. A single cross-section with a thickness of 3 mm was selected, the readout resolution was 1 mm, and the saturation power (B1-sat) was set to 0.2 μT. The number of acquisition spokes in K-space was 151, the minimum TE mode was selected, the flip angle (FA) was 35°, the echo number was 6, and the TR was 66.32 ms. The frequency offset range was -5 ppm to +5 ppm with a step size of 0.2 ppm, and 51 scans were performed (51 images in total). The total scan time for the 51 images was 8.36 minutes. When scanning the S0 images, B1-sat was set to 0 (i.e., proton saturation was no longer performed), the frequency offset range was set to -100 ppm to -100 ppm, and the number of scans was 3.

[0081] The results of the phantom experiment are as follows Figure 5 As shown, CEST images of the phantom were obtained by scanning with the sequence proposed in this application under a 3T magnetic resonance system, and Z-spectrums were generated before and after water-lipid separation. After water-lipid separation, the CEST effect of fat signal basically disappeared in the Z-spectrum. Therefore, this method can effectively address the problem of abdominal fat deposition and eliminate the influence of fat signal on CEST signal quantization.

[0082] In animal experiments, 6-8 week old male SD rats were used. A single cross-section with a thickness of 2.5 mm was selected, with a readout resolution of 1 mm and a saturation power (B1-sat) of 0.1 μT. The number of acquisition rays in K-space was 151, the minimum TE mode was selected, the flip angle (FA) was 35°, the echo number was 6, and the TR was 66.32 ms. The frequency offset range was -4 ppm to +4 ppm, the step size was 0.2 ppm, and the number of scans was 41 (51 images in total). The total scan time for the 41 images was 6.69 minutes. When scanning S0 images, B1-sat was set to 0 (i.e., proton saturation was no longer performed), the frequency offset range was set to -100 ppm to -100 ppm, and the number of scans was 3.

[0083] In animal experiments, CEST images of animal abdomens were acquired using the sequence designed in this application, and Z-spectrums of regions of interest (ROIs) were generated and compared with commonly used FSE sequences. Figure 6 As shown, the signal-to-noise ratio of two adjacent CEST images obtained by traditional magnetic resonance imaging methods abruptly changes. The sequence designed in this application can effectively suppress motion artifacts and obtain a stable Z-spectrum. Animal experiments demonstrate that the sequence designed in this application can effectively suppress motion artifacts.

[0084] Those skilled in the art will understand that, in the above-described method of the specific implementation, the order in which each step is written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of each step should be determined by its function and possible internal logic.

[0085] Please continue reading Figure 7 , Figure 7 This is a schematic diagram of an embodiment of the magnetic resonance chemical exchange saturation transfer imaging system provided in this application. The magnetic resonance chemical exchange saturation transfer imaging system 400 of this application embodiment includes a pulse module 41, an echo module 42, and an imaging module 43.

[0086] The pulse module 41 is used to apply a radio frequency saturation pulse that lasts for a first preset time to the area to be detected.

[0087] The echo module 42 is used to apply a radio frequency echo pulse to the area to be detected and to acquire several gradient echo signals generated after the radio frequency echo pulse is activated.

[0088] The imaging module 43 is used to read the plurality of gradient echo signals along a preset direction using a radial sampling method to generate a magnetic resonance image.

[0089] Please continue reading Figure 8 , Figure 8 This is a schematic diagram of the structure of an embodiment of the magnetic resonance chemical exchange saturation transfer imaging device provided in this application. The magnetic resonance chemical exchange saturation transfer imaging device 500 of this application embodiment includes a processor 51, a memory 52, an input / output device 53, and a bus 54.

[0090] The processor 51, memory 52, and input / output device 53 are connected to the bus 54. The memory 52 stores program data, and the processor 51 is used to execute the program data to implement the magnetic resonance chemical exchange saturation transfer imaging method described in the above embodiments.

[0091] In this embodiment, processor 51 can also be referred to as a CPU (Central Processing Unit). Processor 51 may be an integrated circuit chip with signal processing capabilities. Processor 51 can also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The general-purpose processor can be a microprocessor, or processor 51 can be any conventional processor.

[0092] This application also provides a computer storage medium; please refer to the following: Figure 9 , Figure 9 This is a schematic diagram of a computer storage medium according to an embodiment of the present application. The computer storage medium 600 stores program data 61, which, when executed by a processor, is used to implement the magnetic resonance chemical exchange saturation transfer imaging method of the above embodiment.

[0093] When the embodiments of this application are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0094] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A magnetic resonance chemical exchange saturation transfer imaging method, characterized in that, The magnetic resonance chemical exchange saturation transfer imaging method includes: A radio frequency saturation pulse lasting for a first preset time is applied to the area to be detected; A radio frequency echo pulse is applied to the region to be detected, and several gradient echo signals generated after the radio frequency echo pulse is activated are acquired. Using radial sampling, the gradient echo signals are read along a preset direction to generate a magnetic resonance image; The signal attenuation model of the plurality of gradient echo signals is as follows: ； in, Indicates echo time The echo signal strength at that time N represents the number of echoes; Indicates the water signal strength; This represents the signal intensity of fat; P represents the number of peak components in fat, and the relative amplitude of each component is... ,satisfy , Indicates its corresponding chemical shift; Local magnetization intensity; This represents the chemical shift of the p-th fat peak component relative to water.

2. The magnetic resonance chemical exchange saturation transfer imaging method according to claim 1, characterized in that, The radial sampling method has 151 radial sampling spokes, a first preset time of 50ms, and 6 gradient echoes for each radial sampling.

3. The magnetic resonance chemical exchange saturation transfer imaging method according to claim 1, characterized in that, The magnetic resonance chemical exchange saturation transfer imaging method also includes: Acquire several magnetic resonance images of several gradient echo signals; Using a preset water-fat separation algorithm, magnetic resonance water images and magnetic resonance fat images are separated from the plurality of magnetic resonance images; The magnetic resonance water image is used for signal quantization, and concentration information is obtained based on the signal quantization result.

4. The magnetic resonance chemical exchange saturation transfer imaging method according to claim 3, characterized in that, The preset water-lipid separation algorithm is a self-testing field map estimation algorithm based on multi-resolution local growth.

5. The magnetic resonance chemical exchange saturation transfer imaging method according to claim 3, characterized in that, Before signal quantization using the magnetic resonance water image, the magnetic resonance chemical exchange saturation transfer imaging method further includes: In response to a user instruction, the region of interest corresponding to the user instruction is selected in the magnetic resonance water image.

6. The magnetic resonance chemical exchange saturation transfer imaging method according to claim 5, characterized in that, The signal quantization using the magnetic resonance water image includes: Based on the magnetic resonance water image, obtain the Z spectrum of the pixels in the region of interest; The Z-spectrum was post-processed for correction, symmetry analysis, and multi-pool Lorentz fitting.

7. A magnetic resonance chemical exchange saturation transfer imaging system, characterized in that, The magnetic resonance chemical exchange saturation transfer imaging system performs the magnetic resonance chemical exchange saturation transfer imaging method according to any one of claims 1 to 6, wherein the magnetic resonance chemical exchange saturation transfer imaging system comprises: a pulse module, an echo module, and an imaging module; wherein... The pulse module is used to apply a radio frequency saturation pulse that lasts for a first preset time to the area to be detected; The echo module is used to apply a radio frequency echo pulse to the area to be detected and to acquire several gradient echo signals generated after the radio frequency echo pulse is activated. The imaging module is used to read the plurality of gradient echo signals along a preset direction using a radial sampling method to generate a magnetic resonance image.

8. A magnetic resonance chemical exchange saturation transfer imaging device, characterized in that, The magnetic resonance chemical exchange saturation transfer imaging device includes a memory and a processor coupled to the memory; The memory is used to store program data, and the processor is used to execute the program data to implement the magnetic resonance chemical exchange saturation transfer imaging method as described in any one of claims 1 to 6.

9. A computer storage medium, characterized in that, The computer storage medium is used to store program data, which, when executed by the computer, is used to implement the magnetic resonance chemical exchange saturation transfer imaging method as described in any one of claims 1 to 6.

Images