Method and apparatus for measuring diffusion coefficient of fresh biopsy sample

Abstract

The application provides a fresh biopsy sample diffusion coefficient measurement method and device, the method comprises: enhancing the susceptibility of water molecules in the fresh biopsy sample; after the water molecules in the fresh biopsy sample are magnetically saturated, exciting the water molecules in the fresh biopsy sample to spin; collecting the magnetic resonance signal strength of the spin magnetic moment evolution of the water molecules in the fresh biopsy sample; and determining the diffusion coefficient according to the magnetic resonance signal strength. The application enhances the susceptibility of water molecules in the fresh biopsy sample and excites the water molecules to spin, thereby achieving the effect of enhancing the water molecule magnetic resonance signal, and then collecting the magnetic resonance signal strength of the spin magnetic moment evolution of the water molecules to determine the diffusion coefficient, so that the fresh biopsy sample can be quantitatively measured in terms of diffusion coefficient with high spatial resolution and high imaging efficiency on a low-field nuclear magnetic resonance imaging instrument.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of magnetic resonance imaging technology, and in particular to a fresh biopsy sample diffusion coefficient measurement method and device. BACKGROUND

[0002] The magnetic resonance diffusion imaging examination of the fresh biopsy sample can perform diffusion imaging characterization on the fluid information retaining tissue, make up for the lack of fluid information in the histopathological examination, and provide more abundant pathophysiological information for the medical diagnosis of the patient's disease. There are two types of magnetic resonance imaging systems on the current market: 1. A large medical magnetic resonance imaging system; 2. A small low-field magnetic resonance imaging system.

[0003] However, the traditional medical magnetic resonance imaging instrument is not suitable for the examination of fresh biopsy samples in the pathology department due to its large size, high use and maintenance cost. The small low-field nuclear magnetic instrument can be used to detect fixed samples or non-biological samples, and has low signal sensitivity, long scanning time, and low diffusion measurement efficiency, which is not suitable for the timeliness requirement of fresh biopsy samples.

[0004] In order to facilitate the use and promotion of the pathology department, the diffusion coefficient measurement must be realized on the small low-field nuclear magnetic instrument, and the low resolution, low sensitivity, and long scanning time of this type of system bring technical challenges to the effectiveness and timeliness of the quantitative measurement of the diffusion coefficient of the fresh biopsy sample. SUMMARY

[0005] The present application provides a fresh biopsy sample diffusion coefficient measurement method and device to solve the defect that the small low-field nuclear magnetic instrument cannot meet the effectiveness and timeliness of the quantitative measurement of the diffusion coefficient of the fresh biopsy sample in the prior art.

[0006] The present application provides a fresh biopsy sample diffusion coefficient measurement method applied to a low-field nuclear magnetic resonance imaging instrument, comprising:

[0007] Enhancing the magnetic susceptibility of water molecules in the fresh biopsy sample;

[0008] After the water molecules in the fresh biopsy sample are magnetically saturated, exciting the water molecules in the fresh biopsy sample to spin;

[0009] Collecting the magnetic resonance signal strength of the spin magnetic moment evolution of the water molecules in the fresh biopsy sample;

[0010] Determining the diffusion coefficient according to the magnetic resonance signal strength.

[0011] Optionally, the magnetic resonance signal strength includes: a first magnetic resonance signal strength and a second magnetic resonance signal strength;

[0012] The first magnetic resonance signal strength is a magnetic resonance signal strength acquired without any additional gradient magnetic field;

[0013] The second magnetic resonance signal strength is a magnetic resonance signal strength acquired with a diffusion gradient magnetic field applied;

[0014] Optionally, determining the diffusion coefficient according to the magnetic resonance signal strength comprises:

[0015] Determining a magnetic resonance signal strength decay value according to the first magnetic resonance signal strength and the second magnetic resonance signal strength;

[0016] Determining the diffusion coefficient according to the magnetic resonance signal strength decay value.

[0017] Optionally, enhancing the water molecule magnetization in the fresh biopsy sample comprises:

[0018] Continuously irradiating the fresh biopsy sample by a microwave emission device to excite the electron spins in the fresh biopsy sample;

[0019] Enhancing the water molecule magnetization in the fresh biopsy sample by the electron spins in the fresh biopsy sample.

[0020] Optionally, exciting the water molecules in the fresh biopsy sample to spin comprises:

[0021] Exciting the water molecules in the fresh biopsy sample to spin by a radio frequency pulse until the signal strength of the water molecules in the fresh biopsy sample acquired reaches the maximum.

[0022] Optionally, the formula for calculating the diffusion coefficient is as follows:

[0023]

[0024] In the formula, D is the diffusion coefficient, S0 is the first magnetic resonance signal strength of the water molecules in the fresh biopsy sample free evolution of the spin magnetic moment without any additional diffusion gradient magnetic field, S b is the second magnetic resonance signal strength of the water molecules in the fresh biopsy sample evolution of the spin magnetic moment with a diffusion gradient magnetic field applied, and b is the diffusion gradient sensitivity factor when the diffusion gradient magnetic field is applied.

[0025] The application further provides a fresh biopsy sample diffusion coefficient measuring device applied to a low-field nuclear magnetic resonance imaging instrument, comprising:

[0026] The enhancement module is configured to enhance the water molecule magnetization in the fresh biopsy sample;

[0027] The excitation module is configured to excite the water molecules in the fresh biopsy sample to spin after the water molecule magnetization in the fresh biopsy sample is saturated;

[0028] The acquisition module is configured to acquire a magnetic resonance signal strength of spin magnetic moments of water molecules in the fresh biopsy sample.

[0029] The processing module is configured to determine the diffusion coefficient according to the magnetic resonance signal strength.

[0030] The present application also provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method for measuring the diffusion coefficient of the fresh biopsy sample according to any one of the above embodiments when executing the program.

[0031] The present application also provides a non-transitory computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method for measuring the diffusion coefficient of the fresh biopsy sample according to any one of the above embodiments.

[0032] The present application also provides a computer program product comprising a computer program, wherein the computer program, when executed by a processor, implements the steps of the method for measuring the diffusion coefficient of the fresh biopsy sample according to any one of the above embodiments.

[0033] The present application provides a method and device for measuring the diffusion coefficient of a fresh biopsy sample, which enhances the magnetic susceptibility of water molecules in the fresh biopsy sample and excites the spin of the water molecules, thereby achieving the effect of enhancing the magnetic resonance signal of the water molecules, and then acquiring the magnetic resonance signal strength of the spin magnetic moments of the water molecules to determine the diffusion coefficient, so as to realize the quantitative measurement of the diffusion coefficient of the fresh biopsy sample with high spatial resolution and high imaging efficiency on a low-field nuclear magnetic resonance imaging instrument. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0035] Figure 1 is a flowchart of the method for measuring the diffusion coefficient of the fresh biopsy sample provided by the embodiments of the present application;

[0036] Figure 2 is a schematic diagram of a magnetic resonance imaging sequence provided by the embodiments of the present application;

[0037] Figure 3 is a structural schematic diagram of the device for measuring the diffusion coefficient of the fresh biopsy sample provided by the embodiments of the present application;

[0038] Figure 4 is a structural schematic diagram of the electronic device provided by the embodiments of the present application. DETAILED DESCRIPTION

[0039] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below with reference to the drawings in the present application. Obviously, the described embodiments are only some, but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0040] The terms "first", "second" and the like in the embodiments of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than that illustrated or described herein, and the objects distinguished by "first", "second" are usually a class, not limited to the number of objects, for example, the first object can be one or more.

[0041] Figure 1 is a flowchart of the fresh biopsy sample diffusion coefficient measurement method provided by the embodiments of the present application, as shown in Figure 1 The fresh biopsy sample diffusion coefficient measurement method provided by the embodiments of the present application is applied to a low-field nuclear magnetic resonance imaging instrument, and includes the following steps.

[0042] Step 101, enhancing the magnetic susceptibility of water molecules in the fresh biopsy sample.

[0043] Specifically, the fresh biopsy sample generally includes the diseased tissue or adjacent healthy tissue cut from the patient's body with the consent of the patient or healthy person for the purpose of human disease diagnosis and treatment, or the control tissue of the same part of the healthy person, which is not treated by special chemical reagent. In addition, the fresh biopsy sample also includes the sample cut from the body of other species without special chemical reagent treatment.

[0044] The magnetic susceptibility is a physical quantity representing the magnetic medium property, and the commonly used symbol is cm. The magnetic susceptibility is equal to the ratio of the magnetization M to the magnetic field strength H. Under the condition that the magnetic field strength H is constant, enhancing the magnetic susceptibility can enhance the magnetization M.

[0045] The magnetic susceptibility of the water molecules in the fresh biopsy sample is enhanced, that is, the magnetization of the water molecules in the fresh biopsy sample is enhanced, so as to realize the effect of enhancing the water molecule magnetic resonance signal.

[0046] Optionally, the method for enhancing the magnetic susceptibility of water molecules in the fresh biopsy sample comprises the following steps.

[0047] The fresh biopsy sample is continuously irradiated by the microwave emission device to excite the electron spin in the fresh biopsy sample.

[0048] The water molecule magnetization in the fresh biopsy sample is enhanced by electron spin in the fresh biopsy sample.

[0049] Specifically, Figure 2 is a schematic diagram of a magnetic resonance imaging sequence provided by an embodiment of the application, as Figure 2 As shown, the fresh biopsy sample is first continuously irradiated by a microwave transmitting device, the irradiation duration t1 is 0-10 seconds, the irradiation power is 0-100 watts, and the irradiation frequency is the product of the main magnetic field strength of the magnetic resonance system and the electron spin magnetic ratio. By continuously irradiating the fresh biopsy sample, the electron spin in the fresh biopsy sample is excited, and during the excitation process, the electron will exchange spin with the proton, thereby enhancing the water molecule magnetization and improving the water molecule magnetization which can be used for the excitation of the hydrogen nucleus nuclear magnetic resonance.

[0050] The present application continuously irradiates the fresh biopsy sample by a microwave transmitting device to excite the electron spin in the fresh biopsy sample, and then exchanges spin between the electron and the proton, thereby enhancing the water molecule magnetization and achieving the effect of enhancing the water molecule magnetic resonance signal.

[0051] Step 102, after the water molecule magnetization in the fresh biopsy sample is saturated, the water molecule in the fresh biopsy sample is excited to spin.

[0052] Specifically, after the water molecule magnetization in the fresh biopsy sample is saturated, i.e. the water molecule magnetization no longer increases, the water molecule is immediately excited to spin to make the water molecule produce spin magnetic moment.

[0053] Optionally, exciting the water molecule in the fresh biopsy sample to spin comprises:

[0054] The water molecule in the fresh biopsy sample is excited to spin by a radio frequency pulse until the signal intensity of the water molecule in the fresh biopsy sample collected reaches the highest.

[0055] Specifically, the radio frequency pulse is a slice selection radio frequency pulse, and the water molecule in the fresh biopsy sample at a specific layer is excited to spin by the slice selection radio frequency pulse until the signal intensity of the water molecule in the fresh biopsy sample collected reaches the highest.

[0056] The enhanced magnetization vector is excited to a transverse plane by a slice selection gradient magnetic field in cooperation with a slice selection radio frequency pulse, the transverse plane is an XY plane, the size of the magnetization vector excited to the transverse plane is related to the flip angle of the slice selection pulse, and the expression of the magnetization vector excited to the transverse plane is as follows:

[0057] M xy = M0*sinθ

[0058] Wherein, M xyis the magnetization vector in the transverse plane, M0 is the initial magnetization vector, and theta is the flip angle of the slice selection pulse, and the initial excitation vector maintains the same phase.

[0059] The application uses radio frequency pulses to excite the spins of water molecules in a fresh biopsy sample, and further enhances the magnetic resonance signal of the water molecules.

[0060] Step 103, collecting the magnetic resonance signal strength of the spin magnetic moment evolution of the water molecules in the fresh biopsy sample.

[0061] Specifically, the magnetic resonance signal strength of the spin magnetic moment evolution of the water molecules in the fresh biopsy sample is collected without any additional diffusion gradient magnetic field and with the application of a diffusion gradient magnetic field.

[0062] Optionally, the magnetic resonance signal strength includes: a first magnetic resonance signal strength and a second magnetic resonance signal strength;

[0063] The first magnetic resonance signal strength is the magnetic resonance signal strength collected without any additional diffusion gradient magnetic field.

[0064] The second magnetic resonance signal strength is the magnetic resonance signal strength collected with the application of a diffusion gradient magnetic field.

[0065] Specifically, after the enhanced magnetization vector is excited to the transverse plane, the magnetic resonance signal strength signal is K-space encoded using a phase gradient magnetic field and a frequency gradient magnetic field, so that the phase encoding reaches a first preset position in K-space, and the frequency encoding reaches a second preset position in K-space, realizing frequency pre-spread.

[0066] The specific expression of the value of the phase encoding reaching the corresponding position in k-space is as follows:

[0067] K y (G y )=(γ / 2π)*G y *t

[0068] K y (G y ) represents the value of the phase encoding reaching the corresponding position in k-space, G y is the gradient field amplitude in the phase encoding direction, gamma is the magnetic spin ratio, and t is the duration of the gradient field.

[0069] The specific expression of the value of the frequency encoding reaching the corresponding position in k-space is as follows:

[0070] K x (G x )=(γ / 2π)*G x *t

[0071] K x(G x ) represents the value read out at the corresponding position in k-space of the pre-spread, G x is the gradient field amplitude in the frequency encoding direction, gamma is the gyromagnetic ratio, and t is the duration of the gradient field.

[0072] A direction of measuring diffusion is selected, a diffusion gradient magnetic field is emitted in the selected direction of measuring diffusion, the diffusion gradient magnetic field is a magnetic field of the phase gradient magnetic field and the frequency gradient magnetic field in the direction of measuring diffusion, a focused radio frequency pulse is emitted after an interval time t2, the spin vector of the water molecule is focused, the same diffusion gradient magnetic field is emitted again after an interval time t2, and the diffusion gradient encoding is completed. This step is performed twice, the first time is the diffusion gradient sensitivity factor b equal to 0 when there is no additional diffusion gradient magnetic field, and the second time is the diffusion gradient sensitivity factor b greater than 0 when the diffusion gradient magnetic field is applied.

[0073] The frequency direction gradient is turned on, and the signal is frequency encoded from the second preset position. After the signal acquisition is completed, the dispersion gradient magnetic field in the frequency encoding direction, the phase encoding direction and the layer direction is turned on, the signal is dispersed, and the above steps are repeated until the K-space signal encoding is completed.

[0074] The K-space signal arrangement is taken as the spatial coordinates of Kx and Ky, and the signals corresponding to Kx and Ky are filled. After the K-space signal encoding is completed, the K-space signal can be decomposed into signals of different frequencies and intensities by using two-dimensional Fourier transform, the two-dimensional frequency is the image spatial coordinate after transformation, and the intensity signal corresponding to the frequency corresponds to the signal of each pixel point. The collection of these pixel points is the first magnetic resonance image and the second magnetic resonance image. The first magnetic resonance signal intensity and the second magnetic resonance signal intensity corresponding to each pixel point are read from the obtained first magnetic resonance image and second magnetic resonance image respectively.

[0075] The application determines the magnetic resonance signal intensity decay value by respectively acquiring the magnetic resonance signal intensity of the spin magnetic moment evolution of the water molecules in the fresh biopsy under the condition of no additional diffusion gradient magnetic field and under the condition of applying the diffusion gradient magnetic field, and further improves the feasibility of the quantitative measurement of the diffusion coefficient of the fresh biopsy sample on the low-field nuclear magnetic resonance imaging instrument with high spatial resolution and high imaging efficiency.

[0076] In step 104, the diffusion coefficient is determined according to the magnetic resonance signal intensity.

[0077] Specifically, the diffusion coefficient is determined according to the first magnetic resonance signal intensity acquired under the condition of no additional diffusion gradient magnetic field and the second magnetic resonance signal intensity acquired under the condition of applying the diffusion gradient magnetic field.

[0078] Optionally, determining the diffusion coefficient based on the magnetic resonance signal intensity includes:

[0079] The magnetic resonance signal intensity attenuation value is determined based on the first magnetic resonance signal intensity and the second magnetic resonance signal intensity;

[0080] The diffusion coefficient is determined based on the attenuation value of the magnetic resonance signal intensity.

[0081] Specifically, the attenuation value of the magnetic resonance signal intensity corresponding to each pixel is obtained first, based on the magnetic resonance signal intensity corresponding to each pixel in the first magnetic resonance image and the magnetic resonance signal intensity corresponding to each pixel in the second magnetic resonance image.

[0082] Then, the diffusion coefficient of each pixel is determined based on the attenuation value of the magnetic resonance signal intensity corresponding to each pixel.

[0083] This invention further improves the feasibility of quantitatively measuring the diffusion coefficient of fresh biopsy samples with high spatial resolution and high imaging efficiency on a low-field MRI scanner by qualitatively measuring the diffusion coefficient.

[0084] Optionally, the diffusion coefficient is calculated using the following formula:

[0085]

[0086] In the formula, D is the diffusion coefficient, S0 is the intensity of the first magnetic resonance signal of the free evolution of the spin magnetic moment of water molecules in the fresh biopsy sample without any additional diffusion gradient magnetic field, and S b denoted as , where is the intensity of the second magnetic resonance signal of the spin magnetic moment evolution of water molecules in the fresh biopsy sample under an applied diffusion gradient magnetic field, and b is the diffusion gradient sensitivity factor when the diffusion gradient magnetic field is applied.

[0087] Specifically, the diffusion gradient sensitivity factor is determined by the strength, waveform, and duration of the gradient magnetic field.

[0088] The intensity of the second magnetic resonance signal corresponding to each pixel is compared with the intensity of the first magnetic resonance signal to obtain the attenuation value of the magnetic resonance signal intensity corresponding to each pixel. Then, the attenuation value of the magnetic resonance signal intensity corresponding to each pixel and the diffusion gradient sensitivity factor b when the diffusion gradient magnetic field is applied are substituted into the calculation formula of the diffusion coefficient to obtain the diffusion coefficient at the corresponding position of each pixel.

[0089] This invention further improves the measurement accuracy of the diffusion coefficient through a specific diffusion coefficient calculation formula.

[0090] This invention provides a method for measuring the diffusion coefficient of fresh biopsy samples. By enhancing the magnetic susceptibility of water molecules in fresh biopsy samples and exciting water molecules to spin, the magnetic resonance signal of water molecules is enhanced. The diffusion coefficient is then determined by collecting the magnetic resonance signal intensity of the spin magnetic moment evolution of water molecules. This allows for the quantitative measurement of the diffusion coefficient of fresh biopsy samples with high spatial resolution and high imaging efficiency on a low-field nuclear magnetic resonance imaging (NMR) system.

[0091] Mouse intestinal tissue was scanned using hyperpolarized diffusion magnetic resonance imaging (HMI) sequences on a low-field MRI scanner. The diffusion coefficient of fresh biopsy samples was measured, and data processing and image reconstruction were performed. The test parameters were: magnetic field strength 0.5T, imaging field size 25mm*25mm, echo time (TE) 18.4 ms, repetition time (TR) 1000 ms, 1 slice, flip angle 90°, matrix size 128*128, resolution 0.195mm*0.195mm, average number of scans 2, and scan time 512 seconds. The diffusion gradient sensitivity factor was 0 s / mm without any additional diffusion gradient magnetic field. 2 The diffusion gradient sensitivity factor is 400 s / mm under the applied diffusion gradient magnetic field. 2 Two magnetic resonance images were obtained based on two different diffusion gradient sensitivity factors. The magnetic resonance signal intensity corresponding to each pixel in each image was then obtained. Based on the diffusion coefficient calculation formula, the measurement accuracy of the diffusion coefficient can reach 0.1 mm. 2 / s.

[0092] This invention provides a method for measuring the diffusion coefficient of fresh biopsy samples, achieving a measurement accuracy of 0.1 mm. 2 With a speed of / s, the spatial resolution can reach 0.2mm*0.2mm, and the scanning imaging time can be shortened to 10 minutes. It can realize the quantitative measurement of the diffusion coefficient of fresh samples with high spatial resolution and imaging efficiency, which is helpful for the accurate diagnosis of pathology and the early detection of diseases, and provides technical support for the development of new pathological detection methods.

[0093] Figure 3 This is a schematic diagram of the structure of the diffusion coefficient measuring device for fresh biopsy samples provided in an embodiment of the present invention, as shown below. Figure 3 As shown, the present invention also provides a device for measuring the diffusion coefficient of fresh biopsy samples, applied to a low-field magnetic resonance imaging (MRI) scanner, comprising: an enhancement module 301, an excitation module 302, an acquisition module 303, and a processing module 304, wherein:

[0094] Enhancement module 301 is used to enhance the magnetic susceptibility of water molecules in fresh biopsy samples;

[0095] The excitation module 302 is configured to excite the water molecules in the fresh biopsy sample to spin after the water molecules in the fresh biopsy sample are saturatedly magnetized.

[0096] The acquisition module 303 is configured to acquire the magnetic resonance signal strength of the spin magnetic moment evolution of the water molecules in the fresh biopsy sample.

[0097] The processing module 304 is configured to determine the diffusion coefficient according to the magnetic resonance signal strength.

[0098] Specifically, the fresh biopsy sample diffusion coefficient measuring device provided by the embodiment of the application can realize all the method steps achieved by the method embodiment and achieve the same technical effects. Here, the same parts and beneficial effects in the embodiment as the method embodiment will not be described in detail.

[0099] Figure 4 is a structural schematic diagram of an electronic device provided by the embodiment of the application, as Figure 4 shown, the electronic device can include a processor 401, a communications interface 402, a memory 403, and a communications bus 404, wherein the processor 401, the communications interface 402, and the memory 403 complete mutual communication through the communications bus 404. The processor 401 can invoke the logic instructions in the memory 403 to execute the fresh biopsy sample diffusion coefficient measuring method, which is applied to a low-field nuclear magnetic resonance imaging instrument, and the method includes: enhancing the magnetic susceptibility of the water molecules in the fresh biopsy sample; exciting the water molecules in the fresh biopsy sample to spin after the water molecules in the fresh biopsy sample are saturatedly magnetized; acquiring the magnetic resonance signal strength of the spin magnetic moment evolution of the water molecules in the fresh biopsy sample; and determining the diffusion coefficient according to the magnetic resonance signal strength.

[0100] In addition, the logic instructions in the memory 403 described above can be implemented in the form of a software functional unit and sold or used as an independent product, which can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the application essentially or the part that contributes to the prior art or part of the technical solutions can be embodied in the form of a software product, and the computer software product is stored in a storage medium, includes a plurality of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the method described in the embodiments of the application. The foregoing storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0101] In another aspect, the present application also provides a computer program product, which comprises a computer program stored on a non-transitory computer readable storage medium, the computer program comprising program instructions which, when executed by a computer, enable the computer to perform the fresh biopsy sample diffusion coefficient measurement method provided by any of the above methods, applied to a low-field nuclear magnetic resonance imaging instrument, the method comprising: enhancing the magnetic susceptibility of water molecules in a fresh biopsy sample; after the water molecules in the fresh biopsy sample are magnetically saturated, exciting the water molecules in the fresh biopsy sample to spin; collecting the magnetic resonance signal strength of the spin magnetic moment evolution of the water molecules in the fresh biopsy sample; and determining the diffusion coefficient according to the magnetic resonance signal strength.

[0102] In another aspect, the present application also provides a non-transitory computer readable storage medium, which stores a computer program, the computer program being executed by a processor to implement the fresh biopsy sample diffusion coefficient measurement method provided by any of the above methods, applied to a low-field nuclear magnetic resonance imaging instrument, the method comprising: enhancing the magnetic susceptibility of water molecules in a fresh biopsy sample; after the water molecules in the fresh biopsy sample are magnetically saturated, exciting the water molecules in the fresh biopsy sample to spin; collecting the magnetic resonance signal strength of the spin magnetic moment evolution of the water molecules in the fresh biopsy sample; and determining the diffusion coefficient according to the magnetic resonance signal strength.

[0103] The device embodiments described above are merely illustrative, wherein the units illustrated as separate components can or can not be physically separated, and the components illustrated as units can or can not be physical units, i.e., they can be located in one place, or distributed on multiple network units. Part or all of the modules can be selected to achieve the purpose of the embodiment according to actual needs. Those skilled in the art can understand and implement without creative labor.

[0104] From the above description of the embodiments, those skilled in the art can clearly understand that the embodiments can be implemented by means of software plus necessary universal hardware platforms, and of course can also be implemented by hardware. Based on such understanding, the above technical solutions, essentially or in other words, the part that contributes to the prior art, can be embodied in the form of a software product, which can be stored in a computer readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute the methods described in each embodiment or some parts of the embodiments.

[0105] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method of measuring the diffusion coefficient of a fresh biopsy sample, characterized in that, The application is applied to a low-field nuclear magnetic resonance imaging instrument, and comprises the following steps: Enhancing the magnetization of water molecules in a fresh biopsy sample; After the magnetization of water molecules in the fresh biopsy sample is saturated, exciting the water molecules in the fresh biopsy sample to spin; Collecting the magnetic resonance signal strength of the spin magnetic moment evolution of the water molecules in the fresh biopsy sample; Determining a diffusion coefficient according to the magnetic resonance signal strength; The step of enhancing the magnetization of water molecules in a fresh biopsy sample comprises the following steps: Continuously irradiating the fresh biopsy sample by using a microwave emission device, the irradiation duration t1 is 0-10 seconds, the irradiation duration t1 is not 0 seconds, the irradiation power is 0-100 watts, the irradiation power is not 0 watts, the irradiation frequency is the product of the main magnetic field strength of the magnetic resonance system and the electronic gyromagnetic ratio, the electron spin in the fresh biopsy sample is excited, and the electron will exchange spin with the proton in the exciting process, so as to enhance the magnetization of water molecules in the fresh biopsy sample; The step of exciting the water molecules in the fresh biopsy sample to spin comprises the following steps: Exciting the water molecules in the fresh biopsy sample to spin by using a radio frequency pulse until the signal strength of the water molecules in the fresh biopsy sample collected reaches the maximum.

2. The fresh biopsy sample diffusion coefficient measurement method of claim 1, wherein, The magnetic resonance signal strength comprises a first magnetic resonance signal strength and a second magnetic resonance signal strength; The first magnetic resonance signal strength is the magnetic resonance signal strength collected without any additional diffusion gradient magnetic field; The second magnetic resonance signal strength is the magnetic resonance signal strength collected under the action of a diffusion gradient magnetic field.

3. The fresh biopsy sample diffusion coefficient measurement method of claim 2, wherein, The step of determining a diffusion coefficient according to the magnetic resonance signal strength comprises the following steps: Determining a magnetic resonance signal strength attenuation value according to the first magnetic resonance signal strength and the second magnetic resonance signal strength; Determining a diffusion coefficient according to the magnetic resonance signal strength attenuation value.

4. The fresh biopsy sample diffusion coefficient measurement method of claim 3, wherein, The calculation formula of the diffusion coefficient is as follows: ； where D is the diffusion coefficient, M0is the first magnetic resonance signal intensity of the spin magnetic moment of water molecules in the fresh biopsy sample free-evolving without any additional diffusion gradient magnetic field, M is the second magnetic resonance signal intensity of the spin magnetic moment of water molecules in the fresh biopsy sample evolving under the application of a diffusion gradient magnetic field, and b is the diffusion gradient sensitivity factor when the diffusion gradient magnetic field is applied.

5. A fresh biopsy sample diffusion coefficient measurement device, characterized by, The application is applied to a low-field nuclear magnetic resonance imaging instrument, and comprises the following steps: An enhancement module is used to enhance the magnetization of water molecules in a fresh biopsy sample; An excitation module is used to excite the water molecules in the fresh biopsy sample to spin after the magnetization of the water molecules in the fresh biopsy sample is saturated; A collection module is used to collect the magnetic resonance signal strength of the spin magnetic moment evolution of the water molecules in the fresh biopsy sample; A processing module is used to determine a diffusion coefficient according to the magnetic resonance signal strength; The step of enhancing the magnetization of water molecules in a fresh biopsy sample comprises the following steps: Continuously irradiating the fresh biopsy sample by using a microwave emission device, the irradiation duration t1 is 0-10 seconds, the irradiation duration t1 is not 0 seconds, the irradiation power is 0-100 watts, the irradiation power is not 0 watts, the irradiation frequency is the product of the main magnetic field strength of the magnetic resonance system and the electronic gyromagnetic ratio, the electron spin in the fresh biopsy sample is excited, and the electron will exchange spin with the proton in the exciting process, so as to enhance the magnetization of water molecules in the fresh biopsy sample; The step of exciting the water molecules in the fresh biopsy sample to spin comprises the following steps: Exciting the water molecules in the fresh biopsy sample to spin by using a radio frequency pulse until the signal strength of the water molecules in the fresh biopsy sample collected reaches the maximum.

6. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor, when executing the program, implements the steps of the fresh biopsy sample diffusion coefficient measurement method as claimed in any one of claims 1 to 4.

7. A non-transitory computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program, when executed by the processor, implements the steps of the fresh biopsy sample diffusion coefficient measurement method as claimed in any one of claims 1 to 4.

8. A computer program product comprising a computer program, characterized in that, The computer program, when executed by the processor, implements the steps of the fresh biopsy sample diffusion coefficient measurement method as claimed in any one of claims 1 to 4.

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