Cardiac image acquisition method, device, magnetic resonance equipment and storage medium

Abstract

The present application relates to a cardiac image acquisition method, device, magnetic resonance equipment and storage medium. The method includes: obtaining a preset excitation space of a target scanning layer of a cardiac region, determining a target radio frequency pulse according to the parameters of the preset excitation space and the preset gradient, exciting the preset excitation space with the target radio frequency pulse, sampling the excited excitation space, filling the sampling points into a two-dimensional k-space, reconstructing the image of the two-dimensional k-space, and obtaining a magnetic resonance cardiac image. Since the size of the original field of view space is reduced, it is ensured that the image of the cardiac contraction period can be scanned, and the selection of the two-dimensional k-space can avoid the motion artifacts generated when the heart contracts when the traditional three-dimensional k-space is excited for scanning.

Description

Technical Field

[0001] The present application relates to the field of magnetic resonance technology, and in particular to a cardiac image acquisition method, device, magnetic resonance equipment and storage medium. Background Art

[0002] Magnetic resonance imaging (MRI) systems are widely used in medical diagnosis. For example, cardiac magnetic resonance imaging (CMR) technology is widely used in routine examinations of a patient's heart.

[0003] At present, when using MRI equipment to scan the heart, the ECG triggering method is generally used for scanning. That is, by attaching electrodes to the body surface, when the ECG signal measured by the MRI equipment during the scanning process is displayed as the heart's contraction period, the MRI equipment stops scanning, and when the ECG signal is displayed as the heart's diastole period, the MRI equipment starts scanning.

[0004] However, the current ECG-triggered magnetic resonance cardiac scanning technology has the problem of being unable to obtain cardiac systolic images. Summary of the invention

[0005] Based on this, it is necessary to provide a cardiac image acquisition method, device, magnetic resonance equipment and storage medium capable of acquiring cardiac systolic images in order to solve the above technical problems.

[0006] In a first aspect, the present application provides a method for acquiring a cardiac image, the method comprising:

[0007] Acquire a preset excitation space of a target scanning layer in a heart region; the preset excitation space is smaller than an original field of view space;

[0008] Determining a target radio frequency pulse according to preset excitation space parameters and preset gradient values;

[0009] The preset excitation space is excited by using the target radio frequency pulse, and the excited excitation space is sampled to fill the sampling points into the two-dimensional k-space;

[0010] The two-dimensional k-space is reconstructed to obtain a magnetic resonance cardiac image.

[0011] In one embodiment, a preset excitation space is excited by using a target radio frequency pulse, and the excited excitation space is sampled to fill the sampling points into a two-dimensional k-space, including:

[0012] The preset excitation space is repeatedly excited in multiple time periods using the target radio frequency pulse, and the excitation space corresponding to each time period is sampled, and the sampling points are filled into the two-dimensional k-space corresponding to each time period.

[0013] In one embodiment, a preset excitation space is excited multiple times in multiple consecutive time periods using a target radio frequency pulse, and the excitation space corresponding to each different time period is sampled, and the sampling points are filled into the two-dimensional k-space corresponding to each time period, including:

[0014] In each time period, a target radio frequency pulse is emitted at a preset time interval to perform two-dimensional local excitation on a preset excitation space;

[0015] The excitation space after excitation corresponding to each time period is sampled in a spiral path manner, and the sampling points are filled into the two-dimensional k-space corresponding to each time period.

[0016] In one embodiment, performing image reconstruction on a two-dimensional k-space to obtain a magnetic resonance cardiac image includes:

[0017] The two-dimensional k-space corresponding to each time period is reconstructed to obtain the magnetic resonance cardiac image corresponding to each time period.

[0018] In one embodiment, the cardiac image acquisition method further includes:

[0019] The original field of view spaces of multiple scanning layers of the heart region are sequentially excited by using an initial radio frequency pulse, and the original field of view spaces of each scanning layer are sampled, and the sampling points are filled into the second k space corresponding to each scanning layer;

[0020] Reconstructing the second k-space corresponding to each scanning layer to obtain an initial cardiac image corresponding to each scanning layer;

[0021] Each initial cardiac image is screened to determine the target scanning layer.

[0022] In one embodiment, screening each initial cardiac image to determine a target scanning layer includes:

[0023] Acquiring the heart area of ​​each initial heart image;

[0024] The scanning layer corresponding to the initial heart image with the largest heart region area is determined as the target scanning layer.

[0025] In one embodiment, determining a target radio frequency pulse according to a preset excitation space parameter and a preset gradient value includes:

[0026] The preset parameters of the excitation space and the preset gradient value are substituted into the preset cost function, and the cost function is solved to obtain the pulse amplitude and pulse phase to determine the target radio frequency pulse.

[0027] In a second aspect, the present application provides a cardiac image acquisition device, the device comprising:

[0028] An acquisition module, used for acquiring a preset excitation space of a target scanning layer of a heart region; the preset excitation space is smaller than an original field of view space;

[0029] A determination module, used to determine a target radio frequency pulse according to preset excitation space parameters and preset gradient values;

[0030] An excitation module is used to excite a preset excitation space using a target radio frequency pulse, and to sample the excitation space after excitation, and to fill the sampling points into a two-dimensional k-space;

[0031] The image reconstruction module is used to reconstruct the two-dimensional k-space image to obtain a magnetic resonance cardiac image.

[0032] In a third aspect, the present application provides a magnetic resonance device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the method in any one of the embodiments of the first aspect are implemented.

[0033] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method in any one of the embodiments of the first aspect above.

[0034] The above-mentioned cardiac image acquisition method, device, magnetic resonance equipment and storage medium obtain a preset excitation space of a target scanning layer in the cardiac area, determine a target radio frequency pulse according to the parameters of the preset excitation space and a preset gradient, use the target radio frequency pulse to excite the preset excitation space, sample the excitation space after excitation, fill the sampling points into a two-dimensional k-space, reconstruct the image of the two-dimensional k-space, and obtain a magnetic resonance cardiac image. Since the size of the original field of view space is reduced, it is ensured that the image of the heart's contraction period can be scanned, and the selection of a two-dimensional k-space can avoid motion artifacts generated during heart contraction when scanning with the traditional excitation of a three-dimensional k-space. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic diagram of the imaging time that can be provided by ECG triggering in one embodiment;

[0036] Figure 2 A schematic diagram of a process of obtaining a cardiac image in one embodiment;

[0037] Figure 3 A schematic diagram of setting a target radio frequency pulse and a preset gradient field in one embodiment;

[0038] Figure 4 A schematic diagram of a flow chart of a cardiac image acquisition method in another embodiment;

[0039] Figure 5 A schematic diagram of a preset excitation space for single-shot spiral path acquisition in one embodiment;

[0040] Figure 6 A schematic diagram of a flow chart of a cardiac image acquisition method in another embodiment;

[0041] Figure 7 A schematic diagram of a flow chart of a cardiac image acquisition method in another embodiment;

[0042] Figure 8 is a structural block diagram of a cardiac image acquisition device in one embodiment;

[0043] Fig. 9 FIG. 4 is a diagram showing the internal structure of a magnetic resonance device in one embodiment. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0045] In the prior art, when performing magnetic resonance imaging of the heart, the ECG triggering method is generally used, that is, by attaching electrodes to the surface of the target object to measure the ECG signal during the MRI scanning process. Specifically, when the ECG signal shows the systolic phase, the MRI stops scanning, and when the ECG shows the diastolic phase, the MRI starts scanning. Figure 1 The figure is a schematic diagram of the imaging time that can be provided by the traditional ECG trigger. Since the existing technology stops scanning when the ECG signal is in the systolic period, the traditional ECG trigger cannot obtain the scanning result of the cardiac systolic period. Since the duration of the cardiac systolic period is generally 0.4 seconds. If the traditional magnetic resonance heart scan ignores the ECG trigger and directly scans the heart, assuming that the original field of view space of 48cm*48cm is used, and assuming that the number of sampling points is fixed to 128x128, the bandwidth is 100KHz, the traditional signal acquisition time is about 16ms. Obviously, if the ECG trigger is directly ignored and the magnetic resonance device is directly used to scan the heart area, the image of the cardiac systolic period cannot be scanned.

[0046] Based on this, in one embodiment, Figure 2 As shown, a cardiac image acquisition method is provided. This embodiment uses the method applied to a magnetic resonance device as an example. In this embodiment, the method includes the following steps:

[0047] S202, obtaining a preset excitation space of a target scanning layer of a heart region; the preset excitation space is smaller than the original field of view space.

[0048] Specifically, when performing a magnetic resonance scan, the scan is usually performed in layers. The heart area can be pre-scanned to determine the layer with the largest area in the heart area as the target scanning layer. After the target scanning layer is determined, the user can set a preset excitation space through the excitation space setting interface, or select a default preset excitation space. Since images of the heart's systolic period cannot be scanned when scanning using the original field of view space, the scanning of images of the heart's systolic period can be achieved by setting a preset excitation space that is smaller than the original field of view space. Among them, the preset excitation space is a 2-dimensional k-space and the preset excitation space just covers the contour of the heart.

[0049] Preferably, the area of ​​the preset excitation space is less than or equal to 1 / 4 of the area of ​​the original field of view space. The signal acquisition time in the prior art can be shortened to 1 / 4 of the original time. That is, the 16ms signal acquisition time in the traditional technology is shortened to 0.4s of the heart contraction, so that the image of the heart contraction can be acquired.

[0050] S204, determining a target radio frequency pulse according to preset excitation space parameters and a preset gradient.

[0051] The preset parameters of the excitation space may include: excitation k-space resolution, excitation k-space coverage, regularization coefficient, etc., which are not limited here.

[0052] Specifically, the preset gradient can be determined by the pre-scan parameters and the parameters of the original excitation space, and the amplitude of the preset time-varying gradient is determined. The time-varying gradient amplitude and the parameters of the preset excitation space are substituted into the preset cost function to determine the target RF pulse amplitude and phase.

[0053] Optionally, the time-varying gradient amplitude is determined by the excitation k-space coverage, and the time-varying gradient duration is determined by the excitation k-space resolution, wherein the start and end amplitudes of the time-varying gradient are both zero, and the maximum gradient switching rate meets the maximum gradient switching rate requirement of the gradient coil in the magnetic resonance device.

[0054] Furthermore, in one embodiment, determining the target radio frequency pulse according to the preset excitation space parameters and the preset gradient value includes:

[0055] The preset parameters of the excitation space and the preset gradient value are substituted into the preset cost function, and the cost function is solved to obtain the pulse amplitude and pulse phase to determine the target radio frequency pulse.

[0056] Specifically, the preset parameters of the excitation space and the preset gradient value are substituted into the preset cost function, and the cost function is: Among them, b is the target RF pulse, A is the preset gradient, λ is the regularization coefficient, usually 8, and d is the preset field of view of the excitation space. The cost function is solved using the conjugate gradient method to obtain the amplitude and phase of the target RF pulse. Figure 3 The figure is a schematic diagram of the target RF pulse and the preset gradient field. The time interval between the gradient field and the RF pulse is 10 milliseconds. The excitation k-space path is a 2D spiral path, and the excitation time is about 9 milliseconds.

[0057] S206, using the target radio frequency pulse to excite the preset excitation space, and sampling the excitation space after the excitation, and filling the sampling points into the two-dimensional k space.

[0058] Specifically, a preset excitation space is excited using a target radio frequency pulse with a determined amplitude and phase, and the excited excitation space is sampled to fill the sampling points into the two-dimensional k space. The excited excitation space can be sampled by Cartesian sampling technology, spiral sampling technology, radial sampling technology, Z sampling technology, undersampling technology, etc., which are not limited here.

[0059] S208, reconstructing the two-dimensional k-space to obtain a magnetic resonance cardiac image.

[0060] Specifically, the image reconstruction of the two-dimensional k-space is performed to obtain the magnetic resonance cardiac image, and the image reconstruction can be performed by adopting a two-dimensional Fourier transform technology, a back projection technology (for example, a convolution back projection technology, a filtered back projection technology), an iterative reconstruction technology, etc., without limitation herein. For example, the iterative reconstruction technology may include an algebraic reconstruction technology (ART), a simultaneous iterative reconstruction technology (SIRT), a simultaneous algebraic reconstruction technology (SART), an adaptive statistical iterative reconstruction (ASIR) technology, a model-based iterative reconstruction (MBIR) technology, a sinusoidal-determined iterative reconstruction (SAFIR) technology, etc., or any combination thereof.

[0061] In the above cardiac image acquisition method, a preset excitation space of a target scanning layer of the cardiac area is acquired, a target radio frequency pulse is determined according to the parameters of the preset excitation space and a preset gradient, the preset excitation space is excited by the target radio frequency pulse, and the excited excitation space is sampled, and the sampling points are filled into a two-dimensional k-space, and an image is reconstructed in the two-dimensional k-space to obtain a magnetic resonance cardiac image. Since the size of the original field of view space is reduced, it is ensured that the image of the heart's contraction period can be scanned, and the selection of a two-dimensional k-space can avoid motion artifacts generated during heart contraction when scanning with the traditional excitation of a three-dimensional k-space.

[0062] The above embodiment describes the cardiac image acquisition method. Now, an embodiment is used to further describe how to excite the preset excitation space. In one embodiment, the preset excitation space is excited by using a target radio frequency pulse, and the excited excitation space is sampled, and the sampling points are filled into the two-dimensional k space, including:

[0063] The preset excitation space is repeatedly excited in multiple time periods using the target radio frequency pulse, and the excitation space corresponding to each time period is sampled, and the sampling points are filled into the two-dimensional k-space corresponding to each time period.

[0064] Specifically, since the preset excitation space is a 2D k-space, 2D image data will be generated in the subsequent image reconstruction. In order to display the dynamic image of the heart, the preset excitation space can be repeatedly excited in multiple time periods using the target radio frequency pulse, and the excitation space corresponding to each time period is sampled, and the sampling points are filled into the 2D k-space corresponding to each time period, so that the subsequent image reconstruction generates the corresponding images of each time period, and outputs them sequentially, so that the dynamic image of the heart can be displayed. Among them, the preset time period can be a continuous time period, for example, 30 consecutive minutes are divided into 10 time periods, and each 3 seconds is a time period.

[0065] Further, in one embodiment, if Figure 4 As shown, the preset excitation space is excited multiple times in multiple consecutive time periods using the target radio frequency pulse, and the excitation space after the excitation corresponding to each different time period is sampled, and the sampling points are filled into the two-dimensional k-space corresponding to each time period, including:

[0066] S402, in each time period, transmitting a target radio frequency pulse at a preset time interval to perform two-dimensional local excitation on a preset excitation space;

[0067] S404, sampling the excitation space corresponding to each time period after excitation in a spiral path manner, and filling the sampling points into the two-dimensional k-space corresponding to each time period.

[0068] Specifically, in each time period, target radio frequency pulses are emitted in sequence through multiple radio frequency lamps arranged in sequence on the magnetic resonance device at preset time intervals to perform two-dimensional local excitation on the preset excitation space, and the excitation space after the excitation corresponding to each time period is sampled in a spiral path manner, and the sampling points are filled into the two-dimensional k-space corresponding to each time period. For example, the preset excitation space can be set to 1 / 4 of the original field of view space, that is, the preset excitation space is set to 1 / 2 of the horizontal field of view space * 1 / 2 of the longitudinal field of view space. Among them, the spiral path method can include: single-shot spiral path, multi-shot spiral path, which is not limited here. Figure 5 Schematic diagram of the preset excitation space using single-shot spiral path acquisition.

[0069] In this embodiment, the preset excitation space is repeatedly excited in multiple time periods by using a target radio frequency pulse, and the excitation space corresponding to each time period is sampled, and the sampling points are filled into the two-dimensional k-space corresponding to each time period. The preset excitation space can be excited, and the signal acquisition time can be shortened to realize scanning of the heart's contraction period. The use of two-dimensional k-space can avoid motion artifacts caused by exciting three-dimensional k-space.

[0070] The above embodiment describes the excitation of a preset excitation space. Now, an embodiment is used to further describe image reconstruction after excitation. In one embodiment, image reconstruction is performed on a two-dimensional k-space to obtain a magnetic resonance cardiac image, including:

[0071] The two-dimensional k-space corresponding to each time period is reconstructed to obtain the magnetic resonance cardiac image corresponding to each time period.

[0072] Specifically, two-dimensional Fourier transform is used to reconstruct the two-dimensional k-space corresponding to each time period to obtain a two-dimensional magnetic resonance cardiac image corresponding to each time period.

[0073] Optionally, after the magnetic resonance cardiac images corresponding to the various time periods are obtained, the magnetic resonance cardiac images corresponding to the various time periods are output in the order of the various time periods to form a dynamic effect so as to observe the dynamic cardiac images without motion artifacts.

[0074] In this embodiment, by reconstructing the two-dimensional k-space corresponding to each time period, a two-dimensional magnetic resonance cardiac image corresponding to each time period is obtained, thereby avoiding motion artifacts of a three-dimensional image.

[0075] The above embodiment describes the cardiac image acquisition method. Before scanning the target scanning layer, it is necessary to determine the target scanning layer. Now, an embodiment is used to further describe how to determine the target scanning layer. In one embodiment, Figure 6 As shown, the cardiac image acquisition method further includes:

[0076] S602, using an initial radio frequency pulse to sequentially excite the original field of view spaces of multiple scanning layers of the heart region, and sampling the original field of view space of each scanning layer, and filling the sampling points into the second k space corresponding to each scanning layer.

[0077] Specifically, the original field of view spaces of multiple scanning layers in the heart region are sequentially excited in two dimensions using the initial radio frequency pulse, and the original field of view spaces of each scanning layer are sampled in a spiral path manner, and the sampling points are filled into the second k-space corresponding to each scanning layer. The initial radio frequency pulse is a default pulse preset by the system.

[0078] S604, performing image reconstruction on the second k-space corresponding to each scanning layer to obtain an initial heart image corresponding to each scanning layer.

[0079] Specifically, the second k-space corresponding to each scanning layer is reconstructed using a two-dimensional Fourier transform technique to obtain an initial heart image corresponding to each scanning layer.

[0080] S606, screening each initial cardiac image to determine a target scanning layer.

[0081] Specifically, the initial cardiac images can be screened by obtaining the cardiac area in each initial cardiac image, and determining the scanning layer where the initial cardiac image with the largest cardiac area is located as the target scanning layer. Alternatively, the scanning layer where the initial cardiac image with the most complete contour is located can be used as the target scanning layer, which is not limited here.

[0082] In this embodiment, the original field of view spaces of multiple scanning layers of the heart area are excited in sequence by using an initial radio frequency pulse, and the original field of view space of each scanning layer is sampled, and the sampling points are filled into the second k space corresponding to each scanning layer. Image reconstruction is performed on the second k space corresponding to each scanning layer to obtain an initial heart image corresponding to each scanning layer. Each initial heart image is screened to determine the target scanning layer, and the scanning layer with the most complete heart contour can be determined to ensure the optimal image result of the magnetic resonance scanning of the heart.

[0083] To facilitate understanding by those skilled in the art, a cardiac image acquisition method is further described with an embodiment. In one embodiment, Figure 7 As shown, the cardiac image acquisition method includes:

[0084] S701, using an initial radio frequency pulse to sequentially excite the original field of view spaces of multiple scanning layers of the heart region, and sampling the original field of view space of each scanning layer, and filling the sampling points into the second k space corresponding to each scanning layer.

[0085] S702, performing image reconstruction on the second k-space corresponding to each scanning layer to obtain an initial cardiac image corresponding to each scanning layer.

[0086] S703: Acquire the heart region area of ​​each initial heart image.

[0087] S704: Determine the scanning layer corresponding to the initial heart image with the largest heart region as the target scanning layer.

[0088] S705, obtaining a preset excitation space of a target scanning layer of a heart region; the area of ​​the preset excitation space is less than or equal to 1 / 4 of the area of ​​the original field of view space.

[0089] S706, substituting the preset parameters of the excitation space and the preset gradient value into the preset cost function, solving the cost function, obtaining the pulse amplitude and pulse phase, so as to determine the target radio frequency pulse.

[0090] S707, in each time period, transmitting a target radio frequency pulse at a preset time interval to perform two-dimensional local excitation on a preset excitation space.

[0091] S708, sampling the excitation space corresponding to each time period after excitation in a spiral path manner, and filling the sampling points into the two-dimensional k-space corresponding to each time period.

[0092] S709, reconstructing the two-dimensional k-space corresponding to each time period to obtain the magnetic resonance cardiac image corresponding to each time period.

[0093] In this embodiment, a preset excitation space of a target scanning layer of a cardiac region is acquired, a target radio frequency pulse is determined according to parameters of the preset excitation space and a preset gradient, the preset excitation space is excited by the target radio frequency pulse, and the excited excitation space is sampled, and the sampling points are filled into a two-dimensional k-space, and an image is reconstructed in the two-dimensional k-space to obtain a magnetic resonance cardiac image. Since the size of the original field of view is reduced, it is ensured that images of the cardiac contraction period can be scanned, and the selection of a two-dimensional k-space can avoid motion artifacts generated during cardiac contraction when scanning using the traditional excitation three-dimensional k-space.

[0094] It should be understood that although Figure 1-7The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1-7 At least part of the steps may include multiple steps or multiple stages. These steps or stages are not necessarily performed at the same time, but can be performed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed in turn or alternately with other steps or at least part of the steps or stages in other steps.

[0095] The above embodiment describes the cardiac image acquisition method. Now, an embodiment is used to describe the corresponding cardiac image acquisition device. In one embodiment, Figure 8 As shown, a cardiac image acquisition device is provided, comprising:

[0096] An acquisition module 802 is used to acquire a preset excitation space of a target scanning layer in a heart region; the preset excitation space is smaller than an original field of view space;

[0097] A determination module 804 is used to determine a target radio frequency pulse according to preset excitation space parameters and preset gradient values;

[0098] The excitation module 806 is used to excite the preset excitation space with the target radio frequency pulse, and to sample the excitation space after the excitation, and fill the sampling points into the two-dimensional k space;

[0099] The image reconstruction module 808 is used to reconstruct the two-dimensional k-space image to obtain a magnetic resonance cardiac image.

[0100] Optionally, the area of ​​the preset excitation space is less than or equal to 1 / 4 of the area of ​​the original field of view space.

[0101] In this embodiment, the acquisition module acquires a preset excitation space of a target scanning layer of the heart area, the determination module determines a target radio frequency pulse according to the parameters of the preset excitation space and a preset gradient, the excitation module excites the preset excitation space using the target radio frequency pulse, and samples the excitation space after excitation, and fills the sampling points into the two-dimensional k-space, and the image reconstruction module reconstructs the two-dimensional k-space to obtain a magnetic resonance heart image. Since the size of the original field of view is reduced, it is ensured that the image of the heart's contraction period can be scanned, and the selection of the two-dimensional k-space can avoid motion artifacts generated during heart contraction when scanning with the traditional excitation of the three-dimensional k-space.

[0102] In one embodiment, the excitation module includes:

[0103] The first excitation unit is used to repeatedly excite the preset excitation space in multiple time periods using the target radio frequency pulse, and to sample the excitation space after excitation corresponding to each time period, and to fill the sampling points into the two-dimensional k space corresponding to each time period.

[0104] In one embodiment, the first excitation unit is specifically used to emit target radio frequency pulses at preset time intervals within each time period to perform two-dimensional local excitation on a preset excitation space; the excitation space after excitation corresponding to each time period is sampled in a spiral path manner, and the sampling points are filled into the two-dimensional k-space corresponding to each time period.

[0105] In one embodiment, the image reconstruction module is specifically used to reconstruct the two-dimensional k-space corresponding to each time period to obtain the magnetic resonance cardiac image corresponding to each time period.

[0106] In one embodiment, the heart acquisition device further comprises:

[0107] An initial excitation module is used to sequentially excite the original field of view spaces of multiple scanning layers of the heart region using an initial radio frequency pulse, sample the original field of view space of each scanning layer, and fill the sampling points into the second k space corresponding to each scanning layer;

[0108] An initial image reconstruction module, used for reconstructing the second k-space corresponding to each scanning layer to obtain an initial cardiac image corresponding to each scanning layer;

[0109] The screening module is used to screen each initial cardiac image and determine the target scanning layer.

[0110] In one embodiment, the screening module includes:

[0111] An acquisition unit, used for acquiring the heart region area of ​​each initial heart image;

[0112] The determination unit is used to determine the scanning layer corresponding to the initial heart image with the largest heart region area as the target scanning layer.

[0113] In one embodiment, the determination module is specifically used to substitute preset excitation space parameters and preset gradient values ​​into a preset cost function, solve the cost function, obtain the pulse amplitude and pulse phase, and determine the target radio frequency pulse.

[0114] For the specific definition of the cardiac image acquisition device, please refer to the definition of the cardiac image acquisition method above, which will not be repeated here. Each module in the above cardiac image acquisition device can be implemented in whole or in part by software, hardware and a combination thereof. The above modules can be embedded in or independent of the processor in the magnetic resonance device in the form of hardware, or can be stored in the memory of the magnetic resonance device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0115] In one embodiment, a magnetic resonance device is provided. The magnetic resonance device may be a server, and its internal structure diagram may be as follows: Fig. 9 As shown. The magnetic resonance device includes a processor, a memory and a network interface connected through a system bus. Among them, the processor of the magnetic resonance device is used to provide computing and control capabilities. The memory of the magnetic resonance device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the magnetic resonance device is used to store cardiac image data. The network interface of the magnetic resonance device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a cardiac image acquisition method is implemented.

[0116] Those skilled in the art will understand that Fig. 9 The structure shown in the figure is only a block diagram of a part of the structure related to the present application scheme, and does not constitute a limitation on the magnetic resonance device to which the present application scheme is applied. The specific magnetic resonance device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0117] In one embodiment, a magnetic resonance device is provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps in the above method embodiments when executing the computer program.

[0118] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0119] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0120] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0121] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A cardiac image acquisition method, characterized in that: The method comprises: Acquire a preset excitation space of a target scanning layer of a heart region; the area of ​​the preset excitation space is less than or equal to 1 / 4 of the area of ​​the original field of view space; the preset excitation space just covers the heart contour to achieve scanning of a heart systolic image; Determining a target radio frequency pulse according to the preset excitation space parameters and the preset gradient value; In any one of a plurality of continuous time periods, emitting the target radio frequency pulse at a preset time interval to perform two-dimensional local excitation on the preset excitation space; The excitation space after excitation corresponding to each of the time periods is sampled in a spiral path manner, and the sampling points are filled into the two-dimensional k-space corresponding to each of the time periods; Image reconstruction is performed on the two-dimensional k-space to obtain a magnetic resonance cardiac image.

2. The method according to claim 1, characterized in that The preset parameters of the excitation space include excitation k-space resolution, excitation k-space coverage and a regularization coefficient.

3. The method according to claim 1, characterized in that The preset excitation space includes 1 / 2 of the horizontal field of view space*1 / 2 of the vertical field of view space.

4. The method according to claim 1, characterized in that: The step of reconstructing the two-dimensional k-space to obtain a magnetic resonance cardiac image includes: Image reconstruction is performed on the two-dimensional k-space corresponding to each of the time periods to obtain a magnetic resonance cardiac image corresponding to each of the time periods.

5. The method according to any one of claims 1 to 4, characterized in that: The method further comprises: Using an initial radio frequency pulse to sequentially excite the original field of view spaces of multiple scanning layers of the heart region, and sampling the original field of view spaces of each scanning layer, and filling the sampling points into the second k space corresponding to each scanning layer; Reconstructing the second k-space corresponding to each of the scanning layers to obtain an initial cardiac image corresponding to each of the scanning layers; Each of the initial cardiac images is screened to determine the target scanning layer.

6. The method according to claim 5, characterized in that The screening of each of the initial cardiac images to determine the target scanning layer includes: Acquiring the heart region area of ​​each of the initial heart images; The scanning layer corresponding to the initial heart image having the largest heart region area is determined as the target scanning layer.

7. The method according to claim 1, characterized in that The step of determining a target radio frequency pulse according to the preset excitation space parameters and the preset gradient value includes: The preset parameters of the excitation space and the preset gradient value are substituted into a preset cost function, and the cost function is solved to obtain a pulse amplitude and a pulse phase to determine the target radio frequency pulse.

8. A cardiac image acquisition device, characterized in that: The device comprises: An acquisition module, used for acquiring a preset excitation space of a target scanning layer of a heart region; the area of ​​the preset excitation space is less than or equal to 1 / 4 of the area of ​​the original field of view space; the preset excitation space just covers the heart contour to achieve scanning of a heart systolic image; A determination module, used to determine a target radio frequency pulse according to the preset parameters of the excitation space and the preset gradient value; An excitation module is used to transmit the target radio frequency pulse at a preset time interval in any one of the multiple continuous time periods to perform two-dimensional local excitation on the preset excitation space; the excitation space after excitation corresponding to each of the time periods is sampled in a spiral path manner, and the sampling points are filled into the two-dimensional k space corresponding to each of the time periods; The image reconstruction module is used to reconstruct the two-dimensional k-space to obtain a magnetic resonance cardiac image.

9. A magnetic resonance device, comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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