Functional magnetic resonance imaging method, device, electronic device and storage medium

Abstract

The present application discloses a functional magnetic resonance imaging method, apparatus, electronic device, and storage medium. The method comprises: determining a region to be detected, the region to be detected comprising a plurality of tissues, the signal of each tissue being represented by a magnetization vector; applying a radio frequency pulse to the region to be detected, exciting the magnetization vector in the longitudinal direction of the region to be detected to a position deviating from the longitudinal direction; applying a dephasing gradient to the region to dephasize the magnetization vectors of each tissue in the region to be detected; and performing functional magnetic resonance imaging on the region to be detected to obtain a magnetic resonance image of the region to be detected. The method suppresses specific signals in the region to be detected by combining radio frequency pulses and gradients, thereby obtaining a magnetic resonance signal that does not contain the specific signal. When a magnetic resonance image is generated from the magnetic resonance signal, the magnetic resonance image can be used to analyze neural functional activity.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of computer technology, and specifically to a functional magnetic resonance imaging method, device, electronic device, and storage medium. Background Art

[0002] Functional magnetic resonance imaging (fMRI) is a general term for techniques used to image neural activity. Its basic principle is that neural activation, mediated by neurovascular coupling, causes changes in vasodilation or contraction, blood flow and volume, and the ratio of oxygenated to deoxygenated hemoglobin in the veins, leading to changes in the magnetic resonance signal. Magnetic resonance signals can be used to generate magnetic resonance images, which can then be used to analyze neurovascular activity.

[0003] However, when using functional magnetic resonance imaging to obtain magnetic resonance signals of tissues, they are often easily affected by external factors other than neural stimulation, such as the influence of other tissues outside the imaging area or the influence of field inhomogeneity, resulting in inaccurate quantification of neural activity. Therefore, minimizing the influence of external factors other than neural stimulation is of great significance to the study of neural activity. Summary of the Invention

[0004] The embodiments of the present application provide a functional magnetic resonance imaging method, apparatus, electronic device, and storage medium, which can suppress corresponding tissue signals and obtain a magnetic resonance image after the tissue signals are suppressed.

[0005] In a first aspect, an embodiment of the present application provides a functional magnetic resonance imaging method, comprising:

[0006] determining a region to be detected, where the region to be detected includes a plurality of tissues, and signals of the tissues are represented by magnetization vectors;

[0007] Applying a radio frequency pulse to the area to be detected to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction;

[0008] applying a dephasing gradient to the area to be detected to dephase the magnetization vectors of each tissue in the area to be detected;

[0009] Functional magnetic resonance imaging is performed on the area to be detected to obtain a magnetic resonance image of the area to be detected.

[0010] In a second aspect, an embodiment of the present application further provides a functional magnetic resonance imaging device, comprising:

[0011] a determination module, configured to determine a region to be detected, wherein the region to be detected includes a plurality of tissues, and signals of the tissues are represented by magnetization vectors;

[0012] A radio frequency application module is used to apply radio frequency pulses to the area to be detected, so as to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction;

[0013] a gradient applying module, configured to apply a dephasing gradient to the area to be detected, so as to dephasing the magnetization vectors of the various tissues in the area to be detected;

[0014] The imaging module is used to perform functional magnetic resonance imaging on the area to be detected to obtain a magnetic resonance image of the area to be detected.

[0015] In some embodiments of the present application, the tissue includes blood, and the device further includes a continuing application module, which includes:

[0016] The continuing application unit is used to continue the application process of the radio frequency pulse and the dephasing gradient to the area to be detected until the magnetization vector of the blood meets a first preset condition.

[0017] In some embodiments of the present application, the imaging module includes:

[0018] an applying unit, configured to apply a radio frequency pulse to the area to be detected, so as to excite the magnetization vector in the longitudinal direction of the area to be detected to the transverse direction;

[0019] an acquisition unit, configured to acquire the magnetic resonance signal from the region to be detected after the excitation;

[0020] An imaging unit is used to obtain a magnetic resonance image by performing inverse Fourier transformation, linear or nonlinear iterative reconstruction, or deep learning reconstruction on the frequency domain space of the magnetic resonance signal.

[0021] In some embodiments of the present application, the acquisition unit includes:

[0022] The acquisition subunit is used to acquire the to-be-detected area through an echo acquisition strategy to obtain the magnetic resonance signal to be acquired; wherein the echo acquisition strategy includes at least one of a plane echo, a gradient echo, and a spin echo.

[0023] In some embodiments of the present application, the radio frequency application module includes:

[0024] a scenario determination unit, configured to determine, for the area to be detected, an application scenario based on the area to be detected, the application scenario comprising at least one of a main magnetic field magnitude, a radio frequency emission type, a gradient performance, an energy absorption rate of the area to be detected, or peripheral nerve stimulation of the area to be detected;

[0025] an angle determination unit, configured to determine an application angle of the radio frequency pulse according to the application scenario;

[0026] a radio frequency applying unit, configured to apply radio frequency pulses to the area to be detected according to the application angle, so as to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction;

[0027] The gradient application module includes:

[0028] a numerical value determination unit, configured to determine the application amplitude and application direction of the phase gradient according to the application scenario;

[0029] The gradient applying unit is used to apply a dephasing gradient to the area to be detected according to the applying amplitude and the applying direction, so as to dephase the magnetization vectors of each tissue in the area to be detected.

[0030] In some embodiments of the present application, the radio frequency pulse includes a plurality of sub-radio frequency pulses, and the radio frequency applying unit includes:

[0031] an angle determination subunit, configured to determine a sub-application angle of each of the sub-RF pulses according to the application scenario;

[0032] The RF application sub-unit is used to apply the sub-RF pulses to the area to be detected according to the sub-application angles of the sub-RF pulses, so as to excite the magnetization vector in the longitudinal axis direction of the area to be detected to a position deviating from the longitudinal axis direction.

[0033] In some embodiments of the present application, the magnetic resonance image includes a blood flow suppressed magnetic resonance image, and the apparatus further includes an application module, which includes:

[0034] an image acquisition unit, configured to acquire a non-blood flow suppression image of the area to be detected when the radio frequency pulse and the dephasing gradient are not applied;

[0035] a change determining unit, configured to determine a blood volume change based on the blood flow suppression image and the non-blood flow suppression image;

[0036] An application unit is used to analyze nerve function activities according to the blood volume changes.

[0037] In a third aspect, an embodiment of the present application further provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is executed by the processor, the steps in the above-mentioned functional magnetic resonance imaging method are implemented.

[0038] In a fourth aspect, an embodiment of the present application further provides a storage medium having a computer program stored thereon, which implements the steps in the above-mentioned functional magnetic resonance imaging method when executed by a processor.

[0039] In a fifth aspect, embodiments of the present application further provide a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the methods provided in the various optional implementations described in the embodiments of the present application.

[0040] In one embodiment of the present application, a region to be detected is determined, the region to be detected comprising several tissues, the signals of said tissues being represented by magnetization vectors, a radio frequency pulse is applied to the region to excite the magnetization vectors in the longitudinal direction of the region to be detected to a position deviating from the longitudinal direction, a dephasing gradient is applied to the region to dephasize the magnetization vectors of each tissue in the region to be detected, and functional magnetic resonance imaging is performed on the region to obtain a magnetic resonance image of the region to be detected. Specifically, a combination of radio frequency pulses and gradients is used to suppress specific signals in the region to be detected, thereby obtaining a magnetic resonance signal that does not contain the specific signal. When a magnetic resonance image is generated from the magnetic resonance signal, it is convenient to analyze neural functional activity based on the magnetic resonance image. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in this application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0042] Figure 1 This is a schematic diagram of the process of blood flow inhibition data acquisition in the related technology provided by the embodiment of the present application;

[0043] Figure 2 Schematic diagram of a scenario of a functional magnetic resonance imaging method provided in an embodiment of the present application;

[0044] Figure 3 1 is a flow chart of a functional magnetic resonance imaging method provided in an embodiment of the present application;

[0045] Figure 4 is another flowchart of the functional magnetic resonance imaging method provided in an embodiment of the present application;

[0046] Figure 5 is a schematic structural diagram of a functional magnetic resonance imaging device provided in an embodiment of the present application;

[0047] Figure 6 is another structural schematic diagram of the functional magnetic resonance imaging device provided in an embodiment of the present application;

[0048] Figure 7 It is a structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in this application to clearly and completely describe the technical solutions in this application. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0050] Functional magnetic resonance imaging (fMRI) is a general term for technologies used to image neural activity. Its basic principle is that neural activation, mediated by neurovascular coupling, causes changes in vasodilation or contraction, blood flow and volume, and the ratio of oxygenated to deoxygenated hemoglobin in the veins, leading to changes in the magnetic resonance signal. Magnetic resonance signals can be used to generate magnetic resonance images, which can then be used to analyze neurovascular activity.

[0051] Among them, the functional magnetic resonance imaging method that reflects the changes in the ratio of oxygenated hemoglobin to deoxygenated hemoglobin in the vein is called blood oxygenation level dependent (BOLD). Its basic principle is that oxygenated hemoglobin exhibits antimagnetism and deoxygenated hemoglobin exhibits paramagnetism. When the ratio of the two changes during neural activity, the spin dephasing will slow down, resulting in a high signal on the magnetic resonance image, indirectly reflecting the activation of neurons. The corresponding functional magnetic resonance technology is called blood oxygen level dependent functional magnetic resonance imaging (BOLD-fMRI).

[0052] Ideally, signals from the neuron-rich cortex would originate solely from the blood oxygen level-dependent effect produced by changes in the capillaries or small blood vessels surrounding the neurons. However, in reality, the large blood vessels covering the surface of the cortex (inflow effect and draining vein effect) will also affect the blood oxygen level-dependent effect, thereby affecting the location, amplitude, and timing of the blood oxygen level-dependent signal, leading to inaccurate quantification of neural activity. Therefore, minimizing the intravascular blood signal associated with large vessel inflow and draining vein effects is essential for functional magnetic resonance imaging studies. Functional magnetic resonance imaging based on cerebral blood flow (CBF) can be used to detect more localized neuronal activity because of its increased sensitivity to small vessels and capillaries.

[0053] By leveraging the mechanism by which neuronal stimulation leads to changes in vascular volume and blood volume (CBV), an inversion recovery (IR) pre-pulse is used to zero the blood signal in arteries, arterioles, and capillaries. This is reflected in magnetic resonance imaging as a signal reduction within a local voxel, thereby reflecting local neural functional activity and achieving superior spatial localization capabilities compared to traditional blood oxygen level-dependent methods. We call this technology vascular space occupancy (VASO). Because activation-induced blood volume changes are primarily localized to arterioles and capillaries, VASO-fMRI better localizes neuronal activity in the cortex.

[0054] Currently, VASO-fMRI technology is based on blood flow suppression by inversion recovery IR pulses, where IR includes spatially non-selective and spatially selective (e.g. Figure 1 ) and respectively acquire blood flow suppression images at the blood zero crossing point and non-blood flow suppression images after the blood signal is restored. The changes in cerebral blood flow are calculated based on the numerical values ​​of the two sets of images, thereby reflecting the neural functional activity. However, these solutions all have the following disadvantages, specifically:

[0055] 1. Radio frequency (RF) field inhomogeneity and safety limits on the specific absorption rate (SAR) of transmitted energy may lead to insufficient spin reversal, resulting in poor blood flow suppression and affecting cerebral blood flow and brain function assessment. RF field inhomogeneity is particularly severe at high field intensities.

[0056] The effectiveness of blood flow signal suppression also depends on the time it takes for the reversed arterial blood to flow into and out of the imaging slice. This can lead to uncertainty in cerebral blood volume (CBV) measurements under pathological conditions; on the other hand, the actual inflow effect can interfere with the accuracy of CBV quantification.

[0057] Based on the above situation, embodiments of the present application provide a functional magnetic resonance imaging method, apparatus, electronic device, and storage medium. These methods suppress specific tissue signals through a combination of radiofrequency pulses and gradients, resulting in a magnetic resonance image that does not contain these signals. This facilitates the calculation of specific tissue volumes and facilitates the analysis of neural functional activity.

[0058] Specifically, an embodiment of the present application provides a functional magnetic resonance imaging method suitable for an electronic device, wherein the electronic device includes a terminal or a server, wherein the terminal includes but is not limited to a computer, a magnetic resonance imaging device, etc. The server can be an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, content distribution networks (CDNs), and big data and artificial intelligence platforms. The server can be directly or indirectly connected via wired or wireless communications.

[0059] In the embodiment of the present application, the functional magnetic resonance imaging method can be executed by the terminal device alone, or by the server alone, or by the terminal device and the server together. Figure 2 Taking the terminal device executing the functional magnetic resonance imaging method alone as an example, the specific execution process of the functional magnetic resonance imaging method is as follows:

[0060] The terminal device 10 applies a radio frequency pulse to the area to be detected containing several tissues, and excites the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction. Then, a dephasing gradient is applied to the area to be detected to dephase the magnetization vector of each tissue in the area to be detected. Subsequently, functional magnetic resonance imaging is performed on the area to be detected to obtain a magnetic resonance image of the area to be detected.

[0061] In the embodiment of the present application, after obtaining the magnetic resonance image of the area to be detected, the magnetic resonance image can be displayed in the visual interface of the terminal device 10 or input into the electronic screen of a computer or desktop.

[0062] Among them, in the embodiment of the present application, since the goal is to collect the magnetic resonance signal of the area to be detected under tissue suppression, the application of radio frequency pulses and dephasing gradients can be controlled according to whether the magnetization vector of the tissue is zero. It can also be achieved by applying radio frequency pulses and dephasing gradients multiple times until the magnetization vector of the corresponding tissue is zero.

[0063] For example, in an embodiment of the present application, when the goal is to obtain a magnetic pulse image under blood suppression, the value of the blood magnetization vector can be collected under the action of radio frequency pulses and dephasing gradients, and radio frequency pulses and dephasing gradients can be continuously applied to the area to be detected based on whether the blood magnetization vector is zero. For example, radio frequency pulses and dephasing gradients can be continuously applied to the area to be detected until the magnetization vector of the blood in the area to be detected is zero, thereby obtaining a magnetic resonance signal under blood suppression.

[0064] In one embodiment of the present application, a region to be detected is determined, the region to be detected comprising several tissues, the signals of said tissues being represented by magnetization vectors, a radio frequency pulse is applied to the region to excite the magnetization vectors in the longitudinal direction of the region to be detected to a position deviating from the longitudinal direction, a dephasing gradient is applied to the region to dephasize the magnetization vectors of each tissue in the region to be detected, and functional magnetic resonance imaging is performed on the region to obtain a magnetic resonance image of the region to be detected. Specifically, a combination of radio frequency pulses and gradients is used to suppress specific signals in the region to be detected, thereby obtaining a magnetic resonance signal that does not contain the specific signal. When a magnetic resonance image is generated from the magnetic resonance signal, it is convenient to analyze neural functional activity based on the magnetic resonance image.

[0065] It should be noted that the order of description of the following embodiments does not limit the priority order of the embodiments.

[0066] See also Figure 3 , Figure 3 This is a flow chart of the functional magnetic resonance imaging method provided in an embodiment of the present application. The specific flow of the functional magnetic resonance imaging method can be as follows:

[0067] 101. Determine a region to be detected, where the region to be detected includes several tissues, and signals of the tissues are represented by magnetization vectors.

[0068] In the embodiment of the present application, the area to be detected is an area that requires magnetic resonance imaging, and the area to be detected may include a body part of the human body. The tissue to be detected includes multiple related tissues, for example, gray matter and white matter in the brain, blood, cerebrospinal cord or fat and other human tissues.

[0069] In this embodiment of the present application, the magnetization vector describes the magnetization state of the magnetic medium, including the strength and direction of the magnetization. In this embodiment of the present application, each tissue corresponds to a magnetization vector. After decomposition, the magnetization vector has a net component in the vertical axis and a net component in the horizontal axis. The horizontal axis is the horizontal direction. The net component in the vertical axis is the sum of the vectors in the positive and negative vertical axes, and the net component in the horizontal axis is the sum of the vectors in the 360° horizontal direction.

[0070] Among them, in the embodiment of the present application, the corresponding part can be determined from the human body according to the detection requirements, and the part can be used as the area to be detected. For example, when the human brain needs to be detected, the human head can be used as the area to be detected, and the magnetic resonance image of the brain can be obtained through functional magnetic resonance technology, which facilitates the observation of brain activity based on the magnetic resonance image.

[0071] 102. Apply a radio frequency pulse to the area to be detected to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction.

[0072] In the embodiments of this application, a radio frequency pulse is a pulsed signal. Conventional magnetic resonance imaging (MRI) involves applying radio frequency pulses of a specific frequency to a human body within a magnetic field, exciting hydrogen protons within the body and causing them to resonate. After the pulse stops, the protons generate magnetic resonance signals during their relaxation process. These signals are encoded, received, and reconstructed to produce a static structural image.

[0073] Radio frequency pulses are essential for an MRI sequence; without them, an MRI signal cannot be generated. Electromagnetic vibrations propagate as electromagnetic waves, and the essence of resonance is energy transfer. If we emit a radio frequency (RF) pulse equal to the precession frequency of hydrogen protons in a B0 magnetic field (i.e., the Larmor frequency), the hydrogen protons absorb energy, producing an energy transition known as nuclear magnetic resonance.

[0074] The purpose of applying radio frequency pulses to the area to be detected is to use the radio frequency pulses to change the direction of the magnetization vector in the area to be detected, so that the magnetization vector component in the horizontal direction can be dispersed through the gradient, providing a basis for collecting the desired magnetic resonance signal.

[0075] In the embodiments of the present application, the applied radio frequency pulse can be configured according to the actual scenario to ensure the accuracy and effectiveness of the radio frequency signal. That is, optionally, in some embodiments of the present application, the step of "applying a radio frequency pulse to the area to be detected to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction" includes:

[0076] For the area to be detected, determining an application scenario according to the area to be detected, the application scenario including at least one of the main magnetic field size, radio frequency emission type, gradient performance, energy absorption rate of the area to be detected, or peripheral nerve stimulation of the area to be detected;

[0077] determining an application angle of the radio frequency pulse according to the application scenario;

[0078] A radio frequency pulse is applied to the area to be detected according to the application angle, so as to excite the magnetization vector in the longitudinal axis direction of the area to be detected to a position deviating from the longitudinal axis direction.

[0079] Among them, according to different application scenarios, corresponding RF pulses are configured to improve the effectiveness of RF pulse application, indirectly accelerate the acquisition of effective magnetic resonance signals, and further accelerate the acquisition of effective magnetic resonance images. For example, usually, under a conventional field strength of 3T, the RF pulse angle can be selected between 6° and 12°.

[0080] In the embodiment of the present application, the radio frequency pulse may be a combination of multiple sub-radio frequency pulses, that is, the radio frequency pulse is applied to the area to be detected by multiple sub-radio frequency pulses. That is, optionally, in some embodiments of the present application, the radio frequency pulse includes multiple sub-radio frequency pulses, and the step of "applying the radio frequency pulse to the area to be detected according to the application angle to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction" includes:

[0081] determining a sub-application angle of each of the sub-RF pulses according to the application scenario;

[0082] The sub-RF pulses are applied to the area to be detected according to the sub-application angles of the sub-RF pulses, so as to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction.

[0083] Among them, pulses are applied to the area to be detected at a combination of multiple angles to improve the diversity of RF pulse application methods.

[0084] 103. Apply a dephasing gradient to the area to be detected to dephase the magnetization vectors of each tissue in the area to be detected.

[0085] Among them, in the embodiment of the present application, the magnetic resonance has a total of three physical gradient axes, which provide gradients in the head-foot direction, the up-down direction, and the left-right direction respectively. The gradients in the three directions can be turned on at the same time, and the gradient sizes can also be different. The resulting gradient vector can be oriented in any direction. For example, timing parameters, amplitude parameters, eddy current compensation parameters, etc. are sent to the gradient controller, and the gradient controller sends digital signals to the three gradients in a given timing according to these parameters. After passing through the analog-to-digital converter, the digital signals are converted into analog, low-power gradient field signals.

[0086] Among them, applying a dephasing gradient to the area to be detected can be understood as opening the gradient. Since the magnetic field varies with different spatial positions, that is, the gradient is opened for a certain time, the effect achieved is that the magnetic moments at different positions are subjected to different magnetic fields along the direction of the opening gradient.

[0087] Among them, the existence of the gradient field will lead to phase accumulation. The phase accumulation is different in different spatial positions. The fixed phase accumulation can form a steady state of the signal, or the phase accumulation can be offset by the refocusing pulse, thereby forming a steady-state detectable signal; and for the tissue to be suppressed, the magnetization vector of the tissue in the horizontal direction can be dispersed by the dephasing gradient to obtain the magnetic resonance signal when the magnetization vector of the tissue is zero.

[0088] For example, when it is necessary to obtain a magnetic resonance signal under blood suppression, since the blood is flowing, its accumulated phase is constantly changing and cannot form a steady state, or there is a phase that cannot be refocused. By applying a dephasing gradient, the horizontal magnetization vector is dephased, and the vector sum is zero, which appears as a low signal.

[0089] Therefore, by applying a dephasing gradient to the area to be detected, it is convenient to obtain a magnetic resonance signal when the magnetization vector is zero, and thus it is convenient to obtain a corresponding magnetic resonance image.

[0090] Accordingly, in the embodiments of the present application, the magnitude of the applied dephasing gradient may also be controlled according to the application scenario. That is, optionally, in some embodiments of the present application, the step of "applying a dephasing gradient to the region to be detected to dephase the magnetization vectors of each tissue in the region to be detected" includes:

[0091] Determining the application amplitude and application direction of the phase gradient according to the application scenario;

[0092] A dephasing gradient is applied to the region to be detected according to the applied amplitude and the applied direction, so as to dephase the magnetization vectors of each tissue in the region to be detected.

[0093] The magnitude and direction of the applied dephasing gradient are determined by the application scenario, thereby ensuring the effectiveness of the application of the dephasing gradient and indirectly accelerating the acquisition of magnetic resonance signals and the generation of magnetic resonance images.

[0094] 104. Perform functional magnetic resonance imaging on the area to be detected to obtain a magnetic resonance image of the area to be detected.

[0095] After the corresponding tissue in the area to be detected is suppressed, functional magnetic resonance imaging can be performed on the area to be detected to obtain a corresponding magnetic resonance image.

[0096] In this embodiment of the present application, in order to ensure that a magnetic resonance signal with a magnetization vector signal of zero for the corresponding tissue is obtained, before functional magnetic resonance imaging, radio frequency pulses and dephasing gradients can be continuously applied to ensure that the magnetization vector signal of the corresponding tissue in the area to be detected is zero.

[0097] For example, in the embodiment of the present application, taking the tissue to be suppressed as blood as an example, the purpose is to obtain a magnetic resonance signal when the magnetization vector of the blood is zero, that is, to obtain a magnetic resonance image when the blood is suppressed. That is, optionally, in the embodiment of the present application, the tissue includes blood. Before the step of "performing functional magnetic resonance imaging on the area to be detected to obtain a magnetic resonance image of the area to be detected", the method further includes:

[0098] The process of applying the radio frequency pulse and the dephasing gradient is continued for the area to be detected until the magnetization vector of the blood meets a first preset condition.

[0099] In this embodiment of the present application, when the object to be suppressed is blood, the first preset condition can be set to that the magnetization vector of the blood is zero, that is, the blood signal is zero.

[0100] By continuing the application process of the radio frequency pulse and the dephasing gradient, the magnetization vector of the blood can be dephased to a state that satisfies the first preset condition, ie, the signal of the blood is zero.

[0101] The principle of continuing to apply the RF pulse and turning on the gradient for a certain period of time is the same as the above process (the stopping condition is that the blood signal is 0, that is, the sum of the magnetization vectors is 0; the blood signal can be fully suppressed by continuing the process through multiple RF+gradient cycles. Specifically, the number of cycles of RF pulses and gradients applied is related to the blood area to be suppressed, blood flow velocity, blood vessel size, and the flip angle of the RF pulse. Therefore, the period of continuing to apply the RF pulse and dephasing gradient can be determined based on the blood area to be suppressed, blood flow velocity, blood vessel size, and the flip angle of the RF pulse.

[0102] Among them, the embodiment of the present application utilizes the application of radio frequency pulses and gradients to achieve the goal of the magnetization vector of the blood being 0 (low signal). The manifestation of the unevenness of the radio frequency field is that the flip angle achieved by the radio frequency pulse is not perfect. In the existing technical IR solution, a 180° reversal is originally applied, but it may not reach 180° in some places, which results in the presence of blood signals when the blood signal should pass through zero during the inversion recovery. Our solution is to apply a combination of radio frequency pulses and gradients multiple times to make the magnetization vector of the blood 0, that is, the signal is 0 or low signal, so it doesn’t matter if the angle of the radio frequency pulse flip is not perfect, because: 1. Small-angle radio frequency excitation is insensitive to radio frequency field unevenness; 2. Adiabatic focusing radio frequency pulses can be inserted to alleviate the problem of radio frequency field unevenness. After multiple applications, the vector sum of each magnetic moment in the horizontal direction will be 0, and therefore, it is insensitive to radio frequency field unevenness.

[0103] Furthermore, because blood flow suppression achieved through a combination of RF and gradient imaging relies primarily on blood signal dispersion, it is unrelated to blood flow inflow and outflow within the imaging slice, that is, blood flow velocity. Therefore, a wider range of slices can be selected. However, the effectiveness of IR-based blood flow suppression is related to blood flow inflow and outflow within the slice. Exposing the slice to multiple IR scans (blood flow is too slow) or not experiencing IR (inhomogeneous RF fields or blood flow is too fast) can result in poor blood flow suppression.

[0104] Among them, by periodically applying radio frequency pulses and gradients to the area to be detected, after the blood magnetization vector in the area to be detected is dispersed, the magnetization vectors of other tissues in the area to be detected can be obtained. Among them, since different tissues (blood, brain tissue, etc.) have different intensities in the longitudinal magnetization vector, as well as the influence of the static magnetic field, therefore, in the embodiment of the present application, a part or all of the longitudinal magnetization vector is excited to the horizontal direction by radio frequency pulses, and converted into a magnetic resonance signal that can be read and detected, that is, optionally, in some embodiments of the present application, the step of "performing functional magnetic resonance imaging on the area to be detected to obtain a magnetic resonance image of the area to be detected" includes:

[0105] Applying radio frequency pulses to the area to be detected to excite the magnetization vector in the longitudinal direction of the area to be detected to the transverse direction;

[0106] Collecting the magnetic resonance signal from the excited region to be detected;

[0107] The frequency domain space of the magnetic resonance signal is subjected to inverse Fourier transformation, linear or nonlinear iterative reconstruction, or deep learning reconstruction to obtain a magnetic resonance image.

[0108] The longitudinal magnetization vector is excited to the transverse direction, thereby facilitating the collection of the magnetization vector.

[0109] After the magnetic resonance signal of the area to be detected is collected, an image can be obtained by inverse Fourier transform, linear or nonlinear iterative reconstruction, or deep learning reconstruction of the frequency domain k-space of the obtained magnetic resonance signal.

[0110] In the embodiments of the present application, the magnetic resonance signal of the region to be detected may be acquired by an echo strategy. That is, optionally, in some embodiments of the present application, the step of “acquiring the magnetic resonance signal of the region to be detected after the excitation to obtain the magnetic resonance signal to be acquired” includes:

[0111] Acquiring the area to be detected by an echo acquisition strategy to obtain a magnetic resonance signal to be acquired;

[0112] The echo acquisition strategy includes at least one of planar echo, gradient echo, and spin echo.

[0113] In the embodiments of this application, echo planar imaging (EPI) is a special form of gradient echo that utilizes continuous gradient field direction changes to generate multiple signals for data acquisition. Because the signals acquired by EPI are all generated by gradient field switching, the sequences generated by EPI technology can essentially be classified as gradient echo sequences. EPI technology can be viewed as an echo chain formed by a series of readout gradient fields that alternately change polarity (polarity represents the gradient field direction).

[0114] In the embodiments of this application, the narrowly defined "gradient echo magnetic resonance pulse sequence" of gradient echo refers to "terminated transverse magnetic vector destruction gradient echo angiography." Gradient echo is a nuclear magnetic resonance (NMR) signal generation method that utilizes the polarity reversal of the gradient magnetic field after excitation. When the time-integrated areas of the two polarities cancel each other, the echo reaches its peak. The process of bringing the magnetization vectors (or "magnetization vectors") in the transverse plane perpendicular to the main magnetic field closer together is called "focusing."

[0115] In the embodiments of the present application, spin echoes are a type of signal source in magnetic resonance. In contrast to the free induction decay (FID) that occurs immediately after the first radio frequency (RF) pulse, spin echoes are signals generated by refocusing the de-phased magnetization vector after the second RF pulse. These signals are in contrast to gradient echoes, which achieve focusing using gradient reversal.

[0116] Among them, the echo acquisition strategy can realize the acquisition of magnetic resonance signals and accelerate the formation of magnetic resonance images.

[0117] Among them, in the embodiments of the present application, according to the actual scene requirements, parallel acquisition, pseudo-random acquisition, multi-layer frequency band simultaneous acquisition, wave acquisition, artificial intelligence and other methods can be used to accelerate the acquisition.

[0118] In the embodiment of the present application, after obtaining the magnetic resonance image for blood flow suppression, a non-blood flow suppression image of the area to be detected may also be acquired. Then, based on the comparison between the blood flow suppression image and the non-blood flow suppression image, the change in blood volume is calculated. That is, optionally, in some embodiments of the present application, the magnetic resonance image includes a blood flow suppression magnetic resonance image, and the step of "performing functional magnetic resonance imaging on the area to be detected to obtain a magnetic resonance image of the area to be detected" includes:

[0119] acquiring a non-blood flow suppression image of the area to be detected when the radio frequency pulse and the dephasing gradient are not applied;

[0120] determining a blood volume change based on the blood flow suppressed image and the non-blood flow suppressed image;

[0121] The neural functional activity is analyzed based on the blood volume changes.

[0122] The blood volume change is obtained by comparing the blood flow suppression image with the non-blood flow suppression image, and thus, the neural function activity can be analyzed according to the blood volume change.

[0123] In one embodiment of the present application, a region to be detected is determined, the region to be detected comprising several tissues, the signals of said tissues being represented by magnetization vectors, a radio frequency pulse is applied to the region to excite the magnetization vectors in the longitudinal direction of the region to be detected to a position deviating from the longitudinal direction, a dephasing gradient is applied to the region to dephasize the magnetization vectors of each tissue in the region to be detected, and functional magnetic resonance imaging is performed on the region to obtain a magnetic resonance image of the region to be detected. Specifically, a combination of radio frequency pulses and gradients is used to suppress specific signals in the region to be detected, thereby obtaining a magnetic resonance signal that does not contain the specific signal. When a magnetic resonance image is generated from the magnetic resonance signal, it is convenient to analyze neural functional activity based on the magnetic resonance image.

[0124] See also Figure 4 , Figure 4 FIG. 5 is another flow chart of the functional magnetic resonance imaging method provided in an embodiment of the present application, wherein the functional magnetic resonance imaging process specifically includes:

[0125] 201. Determine a region to be detected, where the region to be detected includes a plurality of tissues, and signals of the tissues are represented by magnetization vectors;

[0126] 202. Apply a radio frequency pulse to the area to be detected to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction;

[0127] 203. Apply a dephasing gradient to the area to be detected to dephasing the magnetization vectors of each tissue in the area to be detected;

[0128] 204. Determine whether the magnetization vector of the blood in the area to be detected is zero. If it is zero, execute 205. If it is not zero, return to step 202.

[0129] In the embodiment of the present application, the RF pulse can be used selectively or non-selectively, the gradient can be applied on different coordinate axes, and the flip angle, phase and time interval of the RF pulse and the gradient size can be kept consistent or changed in the blood flow inhibition part (applying RF pulses and applying dephasing gradients) as required.

[0130] In the embodiments of this application, the RF pulse and gradient settings are determined based on the main magnetic field strength, RF emission, gradient performance, the human body's physiologically acceptable specific absorption rate of transmitted energy, and peripheral nerve stimulation. Typically, at a conventional field strength of 3T, the RF pulse angle can be selected between 6° and 12°, and the single-axis gradient is typically greater than 15mT / m.

[0131] In the embodiment of the present application, the radio frequency pulse may be composed of several sub-radio frequency pulses, such as 90°-180°-90°.

[0132] In the embodiment of the present application, the gradient can be applied in only one direction on the coordinate axis or in multiple directions, and the gradient can be unipolar, bipolar, or even multipolar.

[0133] 205. Collect data from the area to be detected to obtain a magnetic resonance signal;

[0134] Among them, in the embodiments of the present application, planar echo, gradient echo, and spin echo can be used to realize the acquisition of magnetic resonance signals, and parallel acquisition, multi-layer frequency band simultaneous acquisition, wave acquisition, artificial intelligence and other methods can also be used to accelerate the acquisition.

[0135] 206. Obtain a blood-suppressed magnetic resonance image by performing inverse Fourier transform, linear or nonlinear iterative reconstruction, or deep learning reconstruction on the frequency domain space of the magnetic resonance signal;

[0136] 207. Stop applying the radio frequency pulse and the dephasing gradient to the area to be detected to obtain an unsuppressed magnetic resonance signal;

[0137] In the embodiment of the present application, the non-blood-suppressed magnetic resonance signal is similar to a blood oxygenation level dependent (BOLD) signal.

[0138] 208. Obtain a non-blood-suppressed magnetic resonance image by performing inverse Fourier transform, linear or nonlinear iterative reconstruction, or deep learning reconstruction on the frequency domain space of the non-suppressed magnetic resonance signal;

[0139] 209. Calculate changes in cerebral blood volume based on blood-suppressed MRI images and non-blood-suppressed MRI images;

[0140] 210. Analyze neural functional activities based on the changes in cerebral blood volume.

[0141] In the embodiment of the present application, before acquiring the magnetic resonance signal, the fat signal and the cerebrospinal fluid signal can also be suppressed. The fat signal and the cerebrospinal fluid signal suppression are similar to the blood flow signal suppression, and they realize a certain function. Their functions are manifested in the acquired signal (image). For example, for the acquired blood flow suppressed image, in which the blood signal is 0 or low signal, if the fat suppression module is previously applied, then the fat signal in the blood flow suppressed image will also be 0 or low signal. Similarly, if the cerebrospinal fluid suppression module is applied, the cerebrospinal fluid signal in the blood flow suppressed image will also be 0 or low signal.

[0142] The combination of radiofrequency pulses and dephasing gradients is applied to the region to be examined, causing the magnetization vector of blood flow in the region to approach zero, thereby generating a blood flow-suppressed MRI signal. By acquiring blood flow-suppressed and non-blood flow-suppressed MRI images, changes in cerebral blood volume can be calculated based on the difference in image data, providing a data foundation for further analysis of neurological function.

[0143] To facilitate better implementation of the functional magnetic resonance imaging method of the present application, the present application also provides a functional magnetic resonance imaging device based on the above functional magnetic resonance imaging method. The meaning of the third target term is the same as in the above functional magnetic resonance imaging method. For specific implementation details, please refer to the description in the method embodiment.

[0144] See also Figure 5 , Figure 5 : is a schematic structural diagram of a functional magnetic resonance imaging device provided in an embodiment of the present application, wherein the functional magnetic resonance imaging device may include:

[0145] A determination module 301 is configured to determine a region to be detected, where the region to be detected includes a plurality of tissues, and signals of the tissues are represented by magnetization vectors;

[0146] The radio frequency applying module 302 is configured to apply radio frequency pulses to the area to be detected, so as to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction;

[0147] A gradient applying module 303 is configured to apply a dephasing gradient to the region to be detected, so as to dephasing the magnetization vectors of the tissues in the region to be detected;

[0148] The imaging module 304 is configured to perform functional magnetic resonance imaging on the area to be detected to obtain a magnetic resonance image of the area to be detected.

[0149] In some embodiments of the present application, the tissue includes blood, and the device further includes a continuing application module, which includes:

[0150] The continuing application unit is used to continue the application process of the radio frequency pulse and the dephasing gradient to the area to be detected until the magnetization vector of the blood meets a first preset condition.

[0151] In some embodiments of the present application, the imaging module 304 includes:

[0152] an applying unit, configured to apply a radio frequency pulse to the area to be detected, so as to excite the magnetization vector in the longitudinal direction of the area to be detected to the transverse direction;

[0153] an acquisition unit, configured to acquire the magnetic resonance signal from the region to be detected after the excitation;

[0154] An imaging unit is used to obtain a magnetic resonance image by performing inverse Fourier transformation, linear or nonlinear iterative reconstruction, or deep learning reconstruction on the frequency domain space of the magnetic resonance signal.

[0155] In some embodiments of the present application, the acquisition unit includes:

[0156] The acquisition subunit is used to acquire the to-be-detected area through an echo acquisition strategy to obtain the magnetic resonance signal to be acquired; wherein the echo acquisition strategy includes at least one of a plane echo, a gradient echo, and a spin echo.

[0157] In some embodiments of the present application, the RF application module 302 includes:

[0158] a scenario determination unit, configured to determine, for the area to be detected, an application scenario based on the area to be detected, the application scenario comprising at least one of a main magnetic field magnitude, a radio frequency emission type, a gradient performance, an energy absorption rate of the area to be detected, or peripheral nerve stimulation of the area to be detected;

[0159] an angle determination unit, configured to determine an application angle of the radio frequency pulse according to the application scenario;

[0160] a radio frequency applying unit, configured to apply radio frequency pulses to the area to be detected according to the application angle, so as to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction;

[0161] The gradient application module 303 includes:

[0162] a numerical value determination unit, configured to determine the application amplitude and application direction of the phase gradient according to the application scenario;

[0163] The gradient applying unit is used to apply a dephasing gradient to the area to be detected according to the applying amplitude and the applying direction, so as to dephase the magnetization vectors of each tissue in the area to be detected.

[0164] In some embodiments of the present application, the radio frequency pulse includes a plurality of sub-radio frequency pulses, and the radio frequency applying unit includes:

[0165] an angle determination subunit, configured to determine a sub-application angle of each of the sub-RF pulses according to the application scenario;

[0166] The RF application sub-unit is used to apply the sub-RF pulses to the area to be detected according to the sub-application angles of the sub-RF pulses, so as to excite the magnetization vector in the longitudinal axis direction of the area to be detected to a position deviating from the longitudinal axis direction.

[0167] In some embodiments of the present application, the magnetic resonance image includes a blood flow suppressed magnetic resonance image, and the apparatus further includes an application module, which includes:

[0168] an image acquisition unit, configured to acquire a non-blood flow suppression image of the area to be detected when the radio frequency pulse and the dephasing gradient are not applied;

[0169] a change determining unit, configured to determine a blood volume change based on the blood flow suppression image and the non-blood flow suppression image;

[0170] An application unit is used to analyze nerve function activities according to the blood volume changes.

[0171] In the embodiment of the present application, a determination module 301 determines a region to be detected, where the region to be detected includes several tissues, and signals of the tissues are represented by magnetization vectors. Subsequently, a radio frequency application module 302 applies radio frequency pulses to the region to be detected, exciting the magnetization vector in the longitudinal direction of the region to be detected to a position deviating from the longitudinal direction. Next, a gradient application module 303 applies a dephasing gradient to the region to be detected, dephasing the magnetization vectors of each tissue in the region to be detected. Then, an imaging module 304 performs functional magnetic resonance imaging on the region to be detected to obtain a magnetic resonance image of the region to be detected.

[0172] In one embodiment of the present application, a region to be detected is determined, the region to be detected includes several tissues, and the signals of the tissues are represented by magnetization vectors. A radio frequency pulse is applied to the region to excite the magnetization vectors in the longitudinal direction of the region to be detected to a position deviating from the longitudinal direction. A dephasing gradient is applied to the region to dephasize the magnetization vectors of each tissue in the region to be detected. Functional magnetic resonance imaging is performed on the region to obtain a magnetic resonance image of the region to be detected. Specifically, the radio frequency pulse and gradient combination is used to suppress specific signals in the region to be detected, thereby obtaining a magnetic resonance signal that does not contain the specific signal. When a magnetic resonance image is generated from the magnetic resonance signal, it is convenient to analyze neural functional activity based on the magnetic resonance image.

[0173] Among them, see Figure 6 , Figure 6 3 is another structural diagram of the functional magnetic resonance imaging device provided in an embodiment of the present application, wherein the purpose is to achieve three-dimensional cortical functional imaging. For each time resolution TR, there is a corresponding magnetic resonance signal acquisition module 31, wherein each magnetic resonance signal acquisition module 31 includes a blood flow suppression module 311, an auxiliary function module 312, a blood flow suppression acquisition module 313 and a non-blood flow suppression acquisition module 314. Specifically:

[0174] The blood flow suppression module 311 is obtained by combining a radio frequency applying unit and a gradient applying unit, wherein the blood flow suppression module 311 may include a combination of multiple radio frequency applying units and gradient applying units, and is used to suppress blood signals in the area to be detected.

[0175] In this embodiment of the present application, the radio frequency applying unit is used to apply radio frequency pulses RF to the area to be detected. d The gradient applying unit is used to apply a phase gradient G to the area to be detected. d , where the subscript d takes values ​​of 1, 2, 3, …, n.

[0176] In the embodiment of the present application, the RF pulse can be used selectively or non-selectively, the gradient can be applied on different coordinate axes, and the flip angle, phase and time interval of the RF pulse and the gradient size can be kept consistent or changed in the blood flow inhibition part (applying RF pulses and applying dephasing gradients) as required.

[0177] In the embodiments of this application, the RF pulse and gradient settings are determined based on the main magnetic field strength, RF emission, gradient performance, the human body's physiologically acceptable specific absorption rate of transmitted energy, and peripheral nerve stimulation. Typically, at a conventional field strength of 3T, the RF pulse angle can be selected between 6° and 12°, and the single-axis gradient is typically greater than 15mT / m.

[0178] In the embodiment of the present application, the radio frequency pulse may be composed of several sub-radio frequency pulses, such as 90°-180°-90°.

[0179] In the embodiment of the present application, the gradient can be applied on only one coordinate axis or on multiple coordinate axes, and the gradient can be unipolar, bipolar, or even multipolar.

[0180] The auxiliary function module 312 is used to suppress fat signals or cerebrospinal fluid signals.

[0181] The blood flow suppression acquisition module 313 is used to acquire magnetic resonance signals after blood signals are suppressed, or magnetic resonance signals after fat signals are suppressed, or magnetic resonance signals after cerebrospinal fluid signals are suppressed.

[0182] The non-blood flow suppression acquisition module 314 is used to acquire the magnetic resonance signal of the area to be detected when no suppression is performed. The signal is similar to a blood oxygenation level dependent (BOLD) signal.

[0183] Among them, in the embodiment of the present application, since the echo chain cannot be too long, in the embodiment of the present application, the blood flow suppression acquisition module 313 and the non-blood flow suppression acquisition module 314 need to be divided into multiple segments 315 for scanning and segmented acquisition of signal data.

[0184] Among them, the acquisition of a large amount of signal data at multiple time resolutions is conducive to reconstructing three-dimensional (3D) artifact-free magnetic resonance images.

[0185] In addition, the present application also provides an electronic device, such as Figure 7 As shown, it shows a schematic diagram of the structure of the electronic device involved in this application, specifically:

[0186] The electronic device may include one or more processing core processors 401, one or more computer-readable storage media memories 402, a power supply 403, an input unit 404 and other components. Those skilled in the art will understand that Figure 7 The electronic device structure shown in the figure does not constitute a limitation of the electronic device, and may include more or fewer components than shown in the figure, or combine certain components, or arrange components differently.

[0187] Processor 401 is the control center of the electronic device. It connects all parts of the electronic device using various interfaces and circuits. It executes the various functions of the electronic device and processes data by running or executing software programs and / or modules stored in memory 402 and accessing data stored in memory 402. Optionally, processor 401 may include one or more processing cores. Preferably, processor 401 may integrate an application processor and a modem processor. The application processor primarily handles the operating system, object interface, and application programs, while the modem processor primarily handles wireless communications. It is understood that the modem processor may not be integrated into processor 401.

[0188] The memory 402 can be used to store software programs and modules. The processor 401 executes various functional applications and data processing by running the software programs and modules stored in the memory 402. The memory 402 may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc.; the data storage area may store data created according to the use of the electronic device, etc. In addition, the memory 402 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other volatile solid-state storage device. Accordingly, the memory 402 may also include a memory controller to provide the processor 401 with access to the memory 402.

[0189] The electronic device also includes a power supply 403 for supplying power to various components. Preferably, the power supply 403 can be logically connected to the processor 401 via a power management system, thereby enabling the power management system to manage charging, discharging, and power consumption. The power supply 403 can also include one or more DC or AC power supplies, a recharging system, a power failure detection circuit, a power converter or inverter, a power status indicator, and other arbitrary components.

[0190] The electronic device may further include an input unit 404, which may be configured to receive input digital or character information and generate keyboard, mouse, joystick, optical or trackball signal inputs related to object setting and function control.

[0191] Although not shown, the electronic device may further include a display unit, etc., which will not be described in detail herein. Specifically, in this embodiment, the processor 401 in the electronic device loads the executable files corresponding to one or more application processes into the memory 402 according to the following instructions, and the processor 401 runs the application stored in the memory 402, thereby implementing the steps of any of the functional magnetic resonance imaging methods provided in this application.

[0192] In an embodiment of the present application, a region to be detected is determined, the region to be detected comprising several tissues, the signals of the tissues being represented by magnetization vectors. A radio frequency pulse is applied to the region to excite the magnetization vectors in the longitudinal direction of the region to be detected to a position deviating from the longitudinal direction. A dephasing gradient is applied to the region to dephasize the magnetization vectors of the various tissues in the region to be detected. Functional magnetic resonance imaging is performed on the region to obtain a magnetic resonance image of the region to be detected. Specifically, a combination of radio frequency pulses and gradients is used to suppress specific signals in the region to be detected, thereby obtaining a magnetic resonance signal that does not contain the specific signal. When a magnetic resonance image is generated from the magnetic resonance signal, it is convenient to analyze neural functional activity based on the magnetic resonance image.

[0193] Those skilled in the art will appreciate that all or part of the steps in the various methods of the above embodiments may be accomplished by instructions, or by controlling related hardware through instructions. The instructions may be stored in a computer-readable storage medium and loaded and executed by a processor.

[0194] To this end, the present application provides a computer-readable storage medium having a computer program stored thereon. The computer program can be loaded by a processor to execute the steps of any functional magnetic resonance imaging method provided in the present application.

[0195] The computer-readable storage medium may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0196] Since the instructions stored in the computer-readable storage medium can execute the steps in any functional magnetic resonance imaging method provided in the present application, the beneficial effects that can be achieved by any functional magnetic resonance imaging method provided in the present application can be achieved. Please refer to the previous embodiments for details and will not be repeated here.

[0197] The present application also provides a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the methods provided in the various optional implementations described in the present application.

[0198] The above is a detailed introduction to a functional magnetic resonance imaging method, device, electronic device and computer-readable storage medium provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

[0199] It can be understood that in the specific implementation of the present application, when the above embodiments of the present application are applied to specific products or technologies, the user's permission or consent is required for the processing of the relevant data, such as the magnetic resonance signals of the user's body, and the collection, use and processing of the relevant data must comply with the relevant laws, regulations and standards of the relevant countries and regions.

Claims

1. A functional magnetic resonance imaging method, characterized in that: include: determining a region to be detected, where the region to be detected includes a plurality of tissues, and signals of the tissues are represented by magnetization vectors; Applying a radio frequency pulse to the area to be detected to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction; applying a dephasing gradient to the area to be detected to dephase the magnetization vectors of each tissue in the area to be detected; Performing functional magnetic resonance imaging on the area to be detected to obtain a magnetic resonance image of the area to be detected; Applying a radio frequency pulse to the area to be detected to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction includes: For the area to be detected, determining an application scenario according to the area to be detected, the application scenario including at least one of the main magnetic field size, radio frequency emission type, gradient performance, energy absorption rate of the area to be detected, or peripheral nerve stimulation of the area to be detected; determining an application angle of the radio frequency pulse according to the application scenario; Applying a radio frequency pulse to the area to be detected according to the application angle to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction; The step of applying a dephasing gradient to the region to be detected to dephasing the magnetization vectors of each tissue in the region to be detected includes: Determining the application amplitude and application direction of the phase gradient according to the application scenario; A dephasing gradient is applied to the region to be detected according to the applied amplitude and the applied direction, so as to dephase the magnetization vectors of each tissue in the region to be detected.

2. The method according to claim 1, characterized in that The tissue includes blood. Before performing functional magnetic resonance imaging on the area to be detected to obtain a magnetic resonance image of the area to be detected, the method further includes: The process of applying the radio frequency pulse and the dephasing gradient is continued for the area to be detected until the magnetization vector of the blood meets a first preset condition.

3. The method according to claim 2, characterized in that The performing functional magnetic resonance imaging on the area to be detected to obtain a magnetic resonance image of the area to be detected includes: Applying radio frequency pulses to the area to be detected to excite the magnetization vector in the longitudinal direction of the area to be detected to the transverse direction; Collecting the magnetic resonance signal from the excited region to be detected; The frequency domain space of the magnetic resonance signal is subjected to inverse Fourier transformation, linear or nonlinear iterative reconstruction, or deep learning reconstruction to obtain a magnetic resonance image.

4. The method according to claim 3, characterized in that The step of collecting the excited region to be detected to obtain the magnetic resonance signal to be collected includes: Acquiring the area to be detected by an echo acquisition strategy to obtain a magnetic resonance signal to be acquired; The echo acquisition strategy includes at least one of planar echo, gradient echo, and spin echo.

5. The method according to claim 1, wherein The radio frequency pulse includes a plurality of sub-radio frequency pulses, and applying the radio frequency pulse to the area to be detected according to the application angle to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction includes: determining a sub-application angle of each of the sub-RF pulses according to the application scenario; The sub-RF pulses are applied to the area to be detected according to the sub-application angles of the sub-RF pulses, so as to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction.

6. The method according to claim 1, characterized in that The magnetic resonance image includes a blood flow suppression magnetic resonance image. After performing functional magnetic resonance imaging on the area to be detected to obtain the magnetic resonance image of the area to be detected, the method further includes: acquiring a non-blood flow suppression image of the area to be detected when the radio frequency pulse and the dephasing gradient are not applied; determining a blood volume change based on the blood flow suppressed image and the non-blood flow suppressed image; The neural functional activity is analyzed based on the blood volume changes.

7. A functional magnetic resonance imaging device, characterized in that include: a determination module, configured to determine a region to be detected, wherein the region to be detected includes a plurality of tissues, and signals of the tissues are represented by magnetization vectors; A radio frequency application module is used to apply radio frequency pulses to the area to be detected, so as to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction; a gradient applying module, configured to apply a dephasing gradient to the area to be detected, so as to dephasing the magnetization vectors of the various tissues in the area to be detected; An imaging module, configured to perform functional magnetic resonance imaging on the area to be detected to obtain a magnetic resonance image of the area to be detected; Applying a radio frequency pulse to the area to be detected to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction includes: For the area to be detected, determining an application scenario according to the area to be detected, the application scenario including at least one of the main magnetic field size, radio frequency emission type, gradient performance, energy absorption rate of the area to be detected, or peripheral nerve stimulation of the area to be detected; determining an application angle of the radio frequency pulse according to the application scenario; Applying a radio frequency pulse to the area to be detected according to the application angle to excite the magnetization vector in the longitudinal direction of the area to be detected to a position deviating from the longitudinal direction; The step of applying a dephasing gradient to the region to be detected to dephasing the magnetization vectors of each tissue in the region to be detected includes: Determining the application amplitude and application direction of the phase gradient according to the application scenario; A dephasing gradient is applied to the region to be detected according to the applied amplitude and the applied direction, so as to dephase the magnetization vectors of each tissue in the region to be detected.

8. An electronic device, characterized in that: The electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the functional magnetic resonance imaging method according to any one of claims 1 to 6 are implemented.

9. A storage medium, characterized in that: The storage medium stores a computer program, which, when executed by a processor, implements the steps of the functional magnetic resonance imaging method according to any one of claims 1 to 6.

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