CN110068783A - A kind of Chemical Exchange saturation transfer imaging method for eliminating fatty artifact - Google Patents
A kind of Chemical Exchange saturation transfer imaging method for eliminating fatty artifact Download PDFInfo
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Abstract
The invention discloses a kind of Chemical Exchange saturation transfer imaging methods for eliminating fatty artifact, this method includes Image Acquisition and image reconstruction step, and Image Acquisition is the mould figure and phase diagram that magnetic resonance imaging is obtained under conditions of without saturation radio frequency irradiation and under conditions of the irradiation of the saturation radio frequency of different frequency using the gradin-echo of more echoes；Its image reconstruction: based on multimodal fat model to the data reconstruction water figure that acquires under the irradiation without saturation radio frequency, fat figure, field figure and
Description
Technical field
The present invention relates to mr imaging technique fields more particularly to a kind of Chemical Exchange saturation for eliminating fatty artifact to turn
Move imaging method.
Background technique
It is one of mr imaging technique field molecular imaging technology that Chemical Exchange, which magnetizes transfer imaging technology,.When
For exchangeable protons in exogenous or endogenous molecule by after frequency selectivity radio frequency saturation, saturation effect can pass through Chemical Exchange
The proton for passing to Free water, the change for being based ultimately upon water signal are indirectly imaged the molecule comprising exchangeable protons.
Chemical Exchange magnetizes a kind of Imaging Technology of the transfer imaging technology as molecular level, provides molecular level for medical diagnosis on disease
The histopathology information of grade, such as concentration, the pH value of tissue and the temperature of part of imaging target molecules.Due to the skill
The great potential that art shows in the monitoring of brain tumor and the assessment of apoplexy, is increasingly subject to the attention of researcher.The skill at present
Art mainly applies to brain tissue, it is more and more research shows that it also have in body portion (such as mammary gland, prostate, liver) imaging it is huge
Big potentiality, however the fat for being present in body organ can produce into serious artifact the image of the technology.
Currently, having had researcher that traditional suppression rouge technology is applied to body portion Chemical Exchange magnetizes transfer imaging, these
Suppression rouge technology includes that the water excitation technique based on the punching of binomial pulsus durus and the Dixon water rouge based on unimodal fat signal model are rebuild
Technology.In the theoretical hypothesis of these technologies, not only the contribution of multiple spectral peaks present in fat signal is ignored, Er Qiehua
It learns saturation irradiation in exchange magnetization transfer imaging the saturation at each peak of fat is also not given to consider.These are intrinsic to lack
Falling into makes the Chemical Exchange in proper portion magnetize the influence that transfer imaging nevertheless suffers from fatty artifact.
Summary of the invention
The purpose of the invention is to overcome the deficiencies of existing technologies, a kind of accurate chemistry for eliminating fatty artifact is proposed
Exchange saturation transfer imaging method.This method not only allows for tribute of multiple spectral peaks to total fat signal in water rouge reconstruction model
It offers, and considers saturation of the saturation radio frequency irradiation to each peak of fat in Chemical Exchange magnetization transfer imaging.Pass through base
It is calculated in the numerical value of Bloch equation, the signal amplitude at each peak of fat is updated after saturation irradiation.Numerical value calculating also considers
To such as lateral rate of decay of information of tissue localWith the influence of main field inhomogeneities.It is calculated based on numerical value, is used for water
Rouge rebuild fat signal model will one by one voxel, be adaptively updated.Generation Chemical Exchange is satisfied finally, water rouge is rebuild
With water figure needed for transfer imaging and field figure, midfield figure will be further used for correcting the inhomogenous influence for composing Z in field.
To achieve the above object, the present invention takes following technical scheme:
A kind of Chemical Exchange saturation transfer imaging method eliminating fatty artifact, including data acquisition and image reconstruction two
A part.
Part of data acquisition includes that Chemical Exchange saturation transfer image-forming data acquisition and reference data acquire two steps again.
Image acquisition part point includes the following steps:
Step 1: Chemical Exchange saturation transfer image-forming data acquisition is used under the irradiation of the saturation radio frequency of different frequency
The gradin-echo of more echoes of monopole readout gradient obtains the mould figure and phase diagram of magnetic resonance imaging.
Step 2: reference data acquisition is under the irradiation of no saturation radio frequency, using the more echoes of monopole readout gradient
The mould figure and phase diagram of gradin-echo acquisition magnetic resonance imaging.
Image reconstruction part includes the following steps:
Step 1: Mo Tu will be collected and phase diagram generates complex value figure；
Step 2: the image data (reference data) that obtains under the irradiation without saturation radio frequency is rebuild, obtain water figure,
Fat figure, field figure andFigure；Rebuilding will be according to being such as lauched rouge signal model:
Wherein ρwIt is respectively the total signal magnitude of water and fat with ρ；ωpAnd αPIt is the resonant frequency and phase at p-th of fatty peak
To signal amplitudeTEnFor the echo time of n-th of echo；This model hypothesis is every
A voxel lateral rate of decay having the sameΔB0For the intensity (field figure) of local magnetic field deviation；γ is the gyromagnet of proton
Than；For the initial phase of water and fatty precession；
The chemical shift at each peak of fat in water rouge signal model and initial relative magnitude need to be known in advance, as priori
Condition；Due to not having saturation pulse to apply saturation to each fatty peak, these priori conditions are directly used in rouge in formula (1)
The modeling of fat signal.Rebuilding the water figure obtained will act as needed for the imaging of Chemical Exchange saturation transfer with reference to figure；Rebuild acquisition
Figure andFigure will be used as known parameters in next step；The field figure that acquisition is rebuild in this step will also be used for Chemical Exchange saturation
The calibration of magnetic field inhomogeneity in transfer imaging.
Step 3: updating to voxel each fatty peak one by one with numerical method after the saturation radio frequency irradiation of different frequency
Longitudinal magnetization vector；Numerical value, which is calculated, is imaged relevant saturation in Chemical Exchange saturation transfer for the signal at each peak of simulated fat
Evolution under impulse action；Signal, which develops, presses following Bloch equation:
WhereinFor the magnetization vector intensity of the equilibrium state at p-th of fatty peak；WithRespectively p-th
Fatty peak in x, y, the magnetization vector intensity on the direction z；R1WithRespectively longitudinal relaxation rate and lateral rate of decay；ω1
(；) it is the amplitude for being saturated radio frequency profile, assume that saturation radio-frequency pulse applies in the direction of the x axis without loss of generality；ΔωpIt is full
With the difference of the centre frequency of radio-frequency pulse and the resonant frequency at each fatty peak, furthermore local magnetic field deviation (Δ B0) also have to it
It influences:
Δωp=σpγB0+γΔB0-ωRF (3)
Wherein σpIt is the chemical shift at p-th of peak, γ is the gyromagnetic ratio of proton；
From formula (2) and formula (3) it is found that under the saturation radio frequency irradiation of a certain determining frequency, each fatty peak is updated
Numerical value calculating will depend on following parameter: R1,ΔB0；Wherein local parameter related with spaceΔB0It will be using next
From the calculated result in step 2；Assuming that all fatty peak R having the same1, which is considered as R unrelated with spatial position1,
Its occurrence is searched from document to be known；The intensity of saturation radio frequency irradiation can be considered the function changed over time, need to be according to sequence
In specific used saturation radio frequency obtain in advance, and be used as known parameters.The intensity of radio frequency irradiation is saturated in the corresponding sky of image
Between be variation, the B of the acquisition additionally acquired1Field will calibrate it.The differential equation in formula (2) features fatty each
Evolutionary process of the magnetization vector at a peak in the case where being saturated radio frequency irradiation at any time, the primary condition that numerical solution is relied on are step
The relative magnitude at each peak of fat under reset condition used in 2；It has been destroyed by dephasing gradient for lateral magnetization vector,
The? vertical axis component that numerical value calculates the magnetization vector known will be used for the relative signal amplitude intensity at more new fats peak.
Step 4: the image data (data of saturation flags) obtained under the irradiation of saturation radio frequency is rebuild；Rebuilding will
According to water rouge signal model in formula (1), wherein relevant parameter is updated by following requirement: based on the numerical value in step 3
It calculates as a result, updating to image voxel the relative signal amplitude intensity at all fatty peaks one by one；Image space in step 2 is each
PointAccurate valuation water rouge signal model in this step in will act as known parameters；Rebuild by acquisition obtain water figure,
Fat figure and field figure；
Step 5: original Z spectrum is extracted from gained water figure, and according to field figure (the Δ B rebuild in step 20) to its carry out
Field inhomogeneity correction；Z spectrum after correction will be used for asymmetry analysis, to extract the magnetization transition intensity of each target molecules.
Step 2 includes the following steps: again in above-mentioned image reconstruction part
Step 2.1: utilizing R2*-IDEAL algorithm carries out preliminary reconstruction to image, obtains water figure, fat figure, local magnetic field
Figure andThe rough valuation of figure.
Step 2.2: by R2*-IDEAL algorithm generate water figure, fat figure andThe valuation of figure will be transmitted as initial value
To the least square fitting based on modulus value；The objective function of least square fitting based on modulus value is as follows:
WhereinSN, refFor the measured signal of n-th of echo of reference scan；
Step 2.3: water figure that least square fitting based on modulus value generates, fat figure, local magnetic field figure andFigure
Accurate valuation passes to the least square fitting based on complex values as determining parameter, the least square fitting based on complex values
Accurate valuation will be carried out to field figure；The objective function of least square fitting based on complex values is as follows:
WhereinSn,refFor the measured signal of n-th of echo of reference scan；
Step 4 specifically comprises the following steps: in above-mentioned image reconstruction part
Step 4.1: preliminary reconstruction being carried out to image using IDEAL algorithm, obtains estimating roughly for field figure, water figure and fatty figure
Value；
Step 4.2: being schemed using water figure and fat is obtained in previous step as initial value, the least square fitting based on modulus value
Further accurate valuation will be carried out to water figure and fat figure；The objective function of the most Theravada fitting of modulus value is as follows:
Wherein θmag={ ρw,ρf, Sn,labFor the measured signal of n-th of echo of saturation flags scanning.
The invention adopts the above technical scheme, which has the following advantages: by adaptively update each peak of fat by
To saturation radio frequency irradiation after relative magnitude, fatty model can more real surface reach fat signal composition so that water
It is more accurate that rouge is rebuild.Accurate water rouge rebuilds the interference for ensuring fat-free signal in water figure, effectively eliminates chemical friendship
The fatty artifact occurred in saturation transfer imaging is changed, the accuracy of Chemical Exchange saturation transfer imaging can be improved in this method.
Detailed description of the invention
Fig. 1 is imaging sequence schematic diagram；
Fig. 2 is the flow chart of image reconstruction part of the present invention；
Fig. 3 is fatty score chart；
Fig. 4 is the corresponding Z spectrogram of voxel of high-fat score；
Fig. 5 is amido bond proton chemical exchange saturation transfer intensity map.
Specific embodiment
In conjunction with following specific embodiments and attached drawing, the present invention is described in further detail.Implement process of the invention,
Condition, experimental method etc. are among the general principles and common general knowledge in the art, this hair in addition to what is specifically mentioned below
It is bright that there are no special restrictions to content.
Embodiment
The present embodiment is a healthy Healthy Volunteers mammary gland data, and data source is in 3.0T magnetic resonance imaging system, Siemens
System.Chemical Exchange saturation transfer imaging sequence used is shown in Fig. 1.
Image acquisition part point includes the following steps:
Step 1: Chemical Exchange saturation transfer image-forming data acquisition is used under the irradiation of the saturation radio frequency of different frequency
The gradin-echo of more echoes of monopole readout gradient obtains the mould figure and phase diagram of magnetic resonance imaging.Radiation parameters: from-
6ppm to+6ppm amounts to 31 frequency shift (FS)s.Saturation pulse duration 200ms, 6. image acquisition parameter of saturation pulse number: TR/
TE1/ Δ TE=11.0/2.3/1.5ms, number of echoes=5, flip angle=8 °, FOV=320 × 320mm2, matrix size=128
× 128, voxel size=2.5 × 2.5mm2, thickness=6mm.
Step 2: reference data acquisition is under the irradiation of no saturation radio frequency, using the more echoes of monopole readout gradient
The mould figure and phase diagram of gradin-echo acquisition magnetic resonance imaging.One described in Image Acquisition relevant parameter and previous step
It causes.
Image reconstruction part includes the following steps:
Step 1: Mo Tu will be collected and phase diagram generates complex value figure；
Step 2: the image data (reference data) obtained under the irradiation without saturation radio frequency is rebuild to obtain water figure, rouge
Fat figure, field figure andFigure；Rebuilding will be according to being such as lauched rouge signal model:
Wherein ρwAnd ρfThe respectively total signal magnitude of water and fat；ωpAnd αPBe p-th of fatty peak resonant frequency and
Relative signal amplitudeTEnFor the echo time of n-th of echo；This model hypothesis
Each voxel lateral rate of decay having the sameΔB0For the intensity (field figure) of local magnetic field deviation；γ is the rotation of proton
Magnetic ratio；For the initial phase of water and fatty precession；
Used by the present embodiment it is each fat peak chemical shift be 0.60, -0.39, -1.94, -2.60, -3.40, -
3.80 } ppm, relative amplitude are { 0.048,0.039,0.004,0.128,0.693,0.087 }；Due to there is no saturation pulse to each
A fat peak applies saturation, these priori conditions are directly used in the modeling of fat signal in formula (1).Rebuild the water obtained
Figure will act as needed for the imaging of Chemical Exchange saturation transfer with reference to figure；Rebuild obtain field figure andFigure will the conduct in next step
Known parameters；The field figure that acquisition is rebuild in this step will also be used for the school of magnetic field inhomogeneity in the imaging of Chemical Exchange saturation transfer
It is quasi-.
Step 3: updating to voxel each fatty peak one by one with numerical method after the saturation radio frequency irradiation of different frequency
Longitudinal magnetization vector；Numerical value, which is calculated, is imaged relevant saturation in Chemical Exchange saturation transfer for the signal at each peak of simulated fat
Evolution under impulse action；Signal, which develops, presses following Bloch equation:
WhereinFor the magnetization vector intensity of the equilibrium state at p-th of fatty peak；WithRespectively p-th
Fatty peak in x, y, the magnetization vector intensity on the direction z；R1WithRespectively longitudinal relaxation rate and lateral rate of decay；ω1
(t) it is the amplitude of saturation radio frequency profile, assumes that saturation radio-frequency pulse applies in the direction of the x axis without loss of generality；ΔωpIt is full
With the difference of the centre frequency of radio-frequency pulse and the resonant frequency at each fatty peak, furthermore local magnetic field deviation (Δ B0) also have to it
It influences:
Δωp=σpγB0+γΔB0-ωRF (3)
Wherein σpIt is the chemical shift at p-th of peak, γ is the gyromagnetic ratio of proton；
From formula (2) and formula (3) it is found that under the saturation radio frequency irradiation of a certain determining frequency, each fatty peak is updated
Numerical value calculating will depend on following parameter: R1,ΔB0；Wherein local parameter related with spaceΔB0It will be using next
From the calculated result in step 2；Assuming that all fatty peak R having the same1, which is considered as R unrelated with spatial position1,
All fatty peak R having the same are assumed in this1((2.72s-1)；The intensity of saturation radio frequency irradiation can be considered to be become at any time
The function of change need to obtain in advance according to saturation radio frequency used specific in sequence, and be used as known parameters.It is saturated radio frequency irradiation
Intensity is variation in the corresponding space of image, the B obtained using double overturning horn cuppings1It is calibrated field.In formula (2)
The differential equation features evolutionary process of the magnetization vector at each peak of fat in the case where being saturated radio frequency irradiation at any time, numerical solution institute
The primary condition of dependence is the relative magnitude at each peak of fat under reset condition used in step 2；It is sweared for lateral magnetization
Amount is destroyed by dephasing gradient, and the? vertical axis component that numerical value calculates the magnetization vector known will be used for the opposite letter at more new fats peak
Number amplitude intensity.
Step 4: the image data (data of saturation flags) obtained under the irradiation of saturation radio frequency is rebuild；Rebuilding will
According to water rouge signal model in formula (1), wherein relevant parameter is updated by following requirement: based on the numerical value in step 3
It calculates as a result, updating to image voxel the relative signal amplitude intensity at all fatty peaks one by one；Image space in step 2 is each
PointAccurate valuation water rouge signal model in this step in will act as known parameters；Rebuild by acquisition obtain water figure,
Fat figure and field figure；
Step 5: original Z spectrum is extracted from gained water figure, and according to field figure (the Δ B rebuild in step 20) to its carry out
Field inhomogeneity correction；Z spectrum after correction will be used for asymmetry analysis, to extract the magnetization transition intensity of each target molecules.
Z spectrum after correction will be used for asymmetry analysis, to extract the signal strength of the amido bond at 3.5ppm.
Step 2 comprises the following steps again in above-mentioned image reconstruction part:
Step 1: utilizing R2*-IDEAL algorithm carries out preliminary reconstruction to image, obtains water figure, fat figure, local magnetic field figure
AndThe rough valuation of figure.
Step 2: by R2*-IDEAL algorithm generate water figure, fat figure andThe valuation of figure will be passed to as initial value
Least square fitting based on modulus value；The objective function of least square fitting based on modulus value is as follows:
WhereinSn,refFor the measured signal of n-th of echo of reference scan；
Step 3: water figure that least square fitting based on modulus value generates, fat figure, local magnetic field figure andThe essence of figure
True valuation passes to the least square fitting based on complex values as determining parameter, and the least square fitting based on complex values will
Accurate valuation is carried out to field figure；The objective function of least square fitting based on complex values is as follows:
WhereinSn,refFor the measured signal of n-th of echo of reference scan.
Step 4 comprises the following steps again in above-mentioned image reconstruction part:
Step 1: preliminary reconstruction being carried out to image using IDEAL algorithm, obtains estimating roughly for field figure, water figure and fatty figure
Value；
Step 2: using water figure and fat figure is obtained in previous step as initial value, the most Theravada fitting based on modulus value will be right
Water figure and fat figure carry out further accurate valuation；The objective function of the most Theravada fitting of modulus value is as follows:
Wherein θmag={ ρw,ρf, Sn,labFor the measured signal of n-th of echo of saturation flags scanning；
According to the water figure and fat rebuild in reconstruction procedures 2 based on the image data obtained under the irradiation without saturation radio frequency
Figure, utilizes formula PDFF=ρf/(ρf+ρw) calculate fatty score chart (Fig. 3).Fatty score chart accordingly is chosen high in fat inside body of gland
Any of fat content draws corresponding Z spectrum (Fig. 4).Z spectrum does not show fatty artifact in -3.5ppm.The amido bond finally calculated
Corresponding Chemical Exchange saturation transfer signal strength map is shown in Fig. 5, and the figure laying is on the mould figure that reference scan obtains.In chemistry
It exchanges in saturation transfer signal strength map, fat-free body of gland region and high-fat body of gland zone signal intensities are without significance difference
It is different, show that fatty artifact has been eliminated.
Protection content of the invention is not limited to above embodiments.Without departing from the spirit and scope of the invention, originally
Field technical staff it is conceivable that variation and advantage be all included in the present invention, and with appended claims be protect
Protect range.
Claims (1)
1. a kind of Chemical Exchange saturation transfer imaging method for eliminating fatty artifact, which is characterized in that this method includes following tool
Body step:
Step 1: Image Acquisition
1.1 acquire Chemical Exchange saturation transfer imaging data under conditions of the irradiation of the saturation radio frequency of different frequency, using list
The gradin-echo of more echoes of pole readout gradient obtains the mould figure and phase diagram of magnetic resonance imaging；
1.2 acquire reference data under conditions of the irradiation of no saturation radio frequency, using the ladder of more echoes of monopole readout gradient
Spend mould figure and phase diagram that echo sequence obtains magnetic resonance imaging；
Step 2: image reconstruction
The mould figure and phase diagram that collect are generated complex value figure by 2.1；
The image data i.e. reference data that obtains is rebuild under 2.2 pairs of irradiations without saturation radio frequency, obtain water figure, fat figure,
Figure andFigure；Rebuilding will be according to being such as lauched rouge signal model:
Wherein ρwAnd ρfThe respectively total signal magnitude of water and fat；ωpAnd αPIt is the resonant frequency and opposite letter at p-th of fatty peak
Number amplitudeTEnFor the echo time of n-th of echo；The every individual of this model hypothesis
Element lateral rate of decay having the sameΔB0Intensity for local magnetic field deviation is schemed on the spot；γ is the gyromagnetic ratio of proton；
For the initial phase of water and fatty precession；The chemical shift at each peak of fat and initial relative magnitude are directly used in public affairs in this step
The modeling of fat signal in formula (1)；
2.3 update to voxel longitudinal flux of each fatty peak after the saturation radio frequency irradiation of different frequency with numerical method one by one
Change vector；Numerical value is calculated the signal at each peak of simulated fat under the saturation pulse effect in the imaging of Chemical Exchange saturation transfer
Evolution；Signal, which develops, presses following Bloch equation:
WhereinFor the magnetization vector intensity of the equilibrium state at p-th of fatty peak；WithRespectively p-th fat
Peak in x, y, the magnetization vector intensity on the direction z；R1WithRespectively longitudinal relaxation rate and lateral rate of decay；ω1(t) it is
It is saturated the amplitude of radio frequency profile, it is assumed that saturation radio-frequency pulse applies in the direction of the x axis；ΔωpIt is the center for being saturated radio-frequency pulse
The difference of the resonant frequency at frequency and each fatty peak, furthermore local magnetic field deviation delta B0Influence to it:
Δωp=σpγB0+γΔB0-ωRF (3)
Wherein σpIt is the chemical shift at p-th of peak, γ is the gyromagnetic ratio of proton；
Parameter in formula (2) and formula (3)With Δ B0Value will be using calculated result in step 2.2；If all
Fatty peak R having the same1, occurrence is searched from document to be known；The intensity of saturation radio frequency irradiation, which is considered as, to be changed over time
Function, extracted from the data of saturation radio frequency specific used in sequence；The intensity of radio frequency irradiation is saturated in the corresponding sky of image
Between be variation, the B of the acquisition additionally acquired1Field will calibrate it；The differential equation in formula (2) features fatty each
Evolutionary process of the magnetization vector at a peak in the case where being saturated radio frequency irradiation at any time, the primary condition that numerical solution is relied on are step
The relative magnitude at each peak of fat under reset condition used in 2.2；It has been broken by dephasing gradient for lateral magnetization vector
Bad, the? vertical axis component that numerical value calculates the magnetization vector known will be used for the relative signal amplitude intensity at more new fats peak；
The image data i.e. data of saturation flags obtained under the irradiation of 2.4 pairs of saturation radio frequencies are rebuild；Reconstruction will be according to public affairs
Water rouge signal model in formula (1), wherein fat signal model is updated by following requirement: based on the numerical value in step 2.3
It calculates as a result, updating to image voxel the relative signal amplitude intensity at all fatty peaks one by one；Image space in step 2.2
Each pointAccurate valuation water rouge signal model in this step in will act as known parameters；Reconstruction will obtain water figure, rouge
Fat figure and field figure；
2.5 extract original Z spectrum from gained water figure, and according to the field figure Δ B rebuild in step 2.20It is inhomogenous that field is carried out to it
Property correction；Z spectrum after correction will be used for asymmetry analysis, to extract the magnetization transition intensity of each target molecules；Wherein,
The image data i.e. reference data obtained under the irradiation without saturation radio frequency is rebuild described in step 2.2, is specifically included
Following steps:
2.2.1 R is utilized2*-IDEAL algorithm to image carry out preliminary reconstruction, obtain water figure, fat figure, local magnetic field figure and
The rough valuation of figure；
2.2.2 by R2*-IDEAL algorithm generate water figure, fat figure andThe valuation of figure is passed to as initial value based on modulus value
Least square fitting；The objective function of least square fitting based on modulus value is as follows:
WhereinSN, refFor the measured signal of n-th of echo of reference scan；
2.2.3 least square fitting based on modulus value generates water figure, fat figure, local magnetic field figure andThe accurate valuation of figure
The least square fitting based on complex values is passed to as determining parameter, the least square fitting based on complex values will be to field figure
Carry out accurate valuation；The objective function of least square fitting based on complex values is as follows:
WhereinSN, refFor the measured signal of n-th of echo of reference scan；
The step 2.4 specifically comprises the following steps:
2.4.1 preliminary reconstruction is carried out to image using IDEAL algorithm, obtains the rough valuation of field figure, water figure and fatty figure；
2.4.2 using water figure and fat figure is obtained in previous step as initial value, the least square fitting based on modulus value will be to water
Figure and fat figure carry out further accurate valuation；The objective function of the most Theravada fitting of modulus value is as follows:
Wherein θmag={ ρw, ρf, SN, labFor the measured signal of n-th of echo of saturation flags scanning.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110992435A (en) * | 2019-11-06 | 2020-04-10 | 上海东软医疗科技有限公司 | Image reconstruction method and device, and imaging data processing method and device |
| WO2023108325A1 (en) * | 2021-12-13 | 2023-06-22 | 中国科学院深圳先进技术研究院 | Fat quantitative imaging method and apparatus, and device and storage medium thereof |
| CN117765286A (en) * | 2024-02-22 | 2024-03-26 | 清华大学 | method and device for representing water phase state of cement-based material |
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