WO2019036833A1 - Method and apparatus for capturing three-dimensional dynamic magnetic resonance imaging, device, and storage device - Google Patents

Abstract

Applicable in the technical field of dynamic magnetic resonance imaging, provided are a method and apparatus for capturing three dimensional dynamic magnetic resonance imaging, a device, and a storage medium. The method comprises: establishing a spherical coordinate system in a three-dimensional k space of a magnetic resonance imaging system, constructing, on the basis of the spherical coordinate system, a conical surface corresponding to a current count of captures, constructing a spiral track in the conical surface, capturing k space data along the spiral track via the magnetic resonance imaging system, and, when the current count of captures reaches a preset threshold, stopping the capturing of k space data and outputting, otherwise, jumping to the step of constructing the conical surface, thus implementing the continuous capturing of the three-dimensional k space data in three-dimensional dynamic magnetic resonance imaging, allowing data captured in any time window to approach uniform distribution in the three-dimensional spherical k space, allowing more freedom in choosing subsequent image reconstruction data, and increasing the data capturing efficiency of three-dimensional dynamic magnetic resonance imaging and the time resolution of a three-dimensional dynamic magnetic resonance image.

Description

Method, device, device and storage medium for collecting three-dimensional dynamic magnetic resonance imaging Technical field

The invention belongs to the field of dynamic nuclear magnetic resonance imaging technology, and in particular relates to a method, a device, a device and a storage medium for collecting three-dimensional dynamic magnetic resonance imaging.

Background technique

Magnetic Resonance Imaging (MRI) has the advantages of no ionizing radiation, multi-contrast imaging, high soft tissue contrast, and has become an important tool for clinical medical examination. During the magnetic resonance imaging process, the acquired magnetic resonance analog signals are converted into digital signals and filled into k-space, and then the k-space data is reconstructed to obtain a magnetic resonance image. The k-space, also known as Fourier space, is the fill space of the original digital data of the magnetic resonance information with spatially located encoded information.

Three-dimensional dynamic magnetic resonance imaging is a technique for tracking and imaging the dynamic physiological processes or drug metabolism processes of human tissues and organs by using magnetic resonance technology. The basic principle of 3D dynamic magnetic resonance imaging is to generate a series of time-dependent k-space data by repeatedly acquiring the same imaging space. By reconstructing these data, time-dependent magnetic resonance images can be obtained. To the extent that dynamic physiological processes such as tissue and organ (such as heartbeat, drug metabolism, etc.) can be provided. By performing data analysis on these images, a series of quantitative or semi-quantitative parameters can be obtained, which reflect the biological and pathophysiological information during the development of the lesion, and are of great value for research and diagnosis.

At present, the acquisition methods of 3D dynamic magnetic resonance imaging mainly include three-dimensional Cartesian acquisition, three-dimensional radial acquisition, hybrid acquisition of radial and Cartesian, etc. These acquisition methods are based on repeated acquisition of some or all of the k-space data to achieve dynamic Imaging. In the three-dimensional Cartesian acquisition, the coding in three directions of k-space is completed by layer selection gradient, phase encoding gradient and frequency encoding gradient to realize the filling of three-dimensional k-space data. The three-dimensional radial acquisition method achieves the filling of the three-dimensional spherical k-space by simultaneously applying appropriate gradients in three directions of k-space. Both methods need to capture all k-spaces when reconstructing a set of 3D images. The inter-data results in a very low temporal resolution of the obtained three-dimensional dynamic magnetic resonance image. The hybrid acquisition method combining radial and Cartesian generally adopts the acquisition method of radial trajectory based on golden proportional angle in two-dimensional plane, and adopts Cartesian acquisition in the third dimension. This method can be combined with retrospective reconstruction technology. To improve the time resolution to a certain extent, but it is necessary to perform multiple repeated acquisitions, the scanning time is increased, the continuity of the dynamic image is not high, and the method is limited by the acquisition time in the third dimension. Time resolution is difficult to further improve.

Summary of the invention

An object of the present invention is to provide a method, a device, a device and a storage medium for acquiring three-dimensional dynamic magnetic resonance imaging, which are intended to solve the problem that the existing three-dimensional dynamic magnetic resonance imaging acquisition method needs to repeatedly collect all three-dimensional k-space data, or Repeating the acquisition of all or part of the three-dimensional k-space multiple times leads to a problem of low data collection efficiency of three-dimensional dynamic magnetic resonance imaging.

In one aspect, the invention provides a method for acquiring three-dimensional dynamic magnetic resonance imaging, the method comprising the steps of:

Establishing a spherical coordinate system in a three-dimensional k-space of the preset magnetic resonance imaging system, and constructing a conical surface corresponding to the current acquisition number according to the spherical coordinate system;

Constructing a spiral trajectory in the conical surface according to a preset spiral trajectory function, and collecting k-space data through the magnetic resonance imaging system along the spiral trajectory;

When it is detected that the current number of acquisitions reaches a preset threshold, the collection of the k-space data is stopped, and the collected k-space data is output, otherwise, the current collection times are added, and the operation is jumped to the location. The step of constructing a conical surface corresponding to the current number of acquisitions is described.

In another aspect, the present invention provides a three-dimensional dynamic magnetic resonance imaging acquisition apparatus, the apparatus comprising:

a conical surface building unit, configured to establish a spherical coordinate system in a k-space of the preset magnetic resonance imaging system, and construct a conical surface corresponding to the current acquisition number according to the spherical coordinate system;

a spiral collecting unit for constructing a spiral in the conical surface according to a preset spiral trajectory function Tracking, and along the helical trajectory, acquiring k-space data through the magnetic resonance imaging system;

The collecting data output unit is configured to stop collecting the k-space data when the current number of acquisitions reaches a preset threshold, and output the collected k-space data, otherwise, add the current collection number Operating, and triggering the conical surface building unit to perform an operation of constructing a conical surface corresponding to the current number of acquisitions.

In another aspect, the present invention also provides a medical device comprising a memory, a processor, and a computer program stored in the memory and operable on the processor, the processor implementing the computer program The steps described in the acquisition method of a three-dimensional dynamic magnetic resonance imaging as described above.

In another aspect, the present invention also provides a computer readable storage medium storing a computer program that, when executed by a processor, implements acquisition of a three-dimensional dynamic magnetic resonance imaging as described above Method described.

The invention establishes a spherical coordinate system in the k-space of the preset three-dimensional dynamic magnetic resonance imaging system, constructs a conical surface corresponding to the current acquisition number according to the spherical coordinate system, and constructs a spiral trajectory in the conical surface according to the spiral trajectory function, and The k-space data is collected along the spiral trajectory by the magnetic resonance imaging system. When the current acquisition times of the detection channel reaches a preset threshold, the acquisition of the k-space data is stopped, and the acquired k-space data is output, otherwise the step of jumping to constructing the conical surface is performed. The k-space data acquisition is continued, so that the k-space data is continuously acquired through the spherical coordinates, the conical surface and the spiral trajectory, and the approximate uniform k-space data distribution can be obtained in any acquisition time window, so that the subsequent image reconstruction data is selected. It is more free and effectively improves the data acquisition efficiency of 3D dynamic magnetic resonance imaging and the temporal resolution of 3D dynamic magnetic resonance images obtained by subsequent reconstruction.

DRAWINGS

1 is a flowchart showing an implementation of a method for collecting three-dimensional dynamic magnetic resonance imaging according to Embodiment 1 of the present invention;

2 is a diagram showing an example of an elevation angle of a conical surface and an initial azimuth of a spiral locus in a spherical coordinate system in a method for acquiring a three-dimensional dynamic magnetic resonance imaging according to Embodiment 1 of the present invention;

3 is a diagram showing an example of distribution of a spiral track continuously acquired three times and a spiral track continuously collected 300 times in a spherical coordinate system in a three-dimensional dynamic magnetic resonance imaging acquisition method according to Embodiment 1 of the present invention;

4 is a diagram showing an example of a point distribution of a spiral track end on a virtual spherical surface after 500 consecutive acquisitions in a three-dimensional dynamic magnetic resonance imaging acquisition method according to Embodiment 1 of the present invention;

FIG. 5 is a diagram showing an example of a point distribution of a spiral track end on a virtual spherical surface in a three-dimensional dynamic magnetic resonance imaging acquisition method according to a first embodiment of the present invention, with different acquisition times, different time windows, and different time combinations;

6 is a schematic diagram of a preferred structure of a three-dimensional dynamic magnetic resonance imaging acquisition apparatus according to Embodiment 2 of the present invention;

FIG. 7 is a schematic diagram of a preferred structure of a three-dimensional dynamic magnetic resonance imaging acquisition apparatus according to Embodiment 2 of the present invention;

FIG. 8 is a schematic structural diagram of a medical device according to Embodiment 3 of the present invention.

Detailed ways

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The specific implementation of the present invention is described in detail below in conjunction with specific embodiments:

Embodiment 1:

FIG. 1 is a flowchart showing an implementation process of a method for collecting three-dimensional dynamic magnetic resonance imaging according to Embodiment 1 of the present invention. For convenience of description, only parts related to the embodiment of the present invention are shown, which are described in detail as follows:

In step S101, a spherical coordinate system is established in the three-dimensional k-space of the preset magnetic resonance imaging system.

In step S102, a conical surface corresponding to the current acquisition number is constructed according to the established spherical coordinate system.

In an embodiment of the invention, the magnetic resonance imaging system may be referred to herein as a three-dimensional dynamic magnetic resonance imaging system, and the three-dimensional k-space is the filling space of the raw data acquired by the magnetic resonance imaging system. Before the magnetic resonance imaging system acquires k-space data (that is, collects the original data used to fill the k-space), in three-dimensional k A spherical coordinate system is established in the space to acquire k-space data in the k-space of the three-dimensional sphere.

In the embodiment of the present invention, when k-space data acquisition is performed, a conical surface corresponding to the current acquisition number is first established in the spherical coordinate system, and specifically, the current collection times may be calculated according to a preset two-dimensional golden division ratio coefficient. The elevation angle of the corresponding conical surface in the spherical coordinate system is based on the elevation angle, and the origin of the spherical coordinate system is the apex of the conical surface, and the conical surface corresponding to the current acquisition number is constructed. Wherein, the formula for calculating the elevation angle of the conical surface in the spherical coordinate system may be:

θ _n =arcsin(2mod(n ₁ γ ₁ ,1)-1), where n ₁ =n+i, n is the current number of acquisitions, n is a positive integer greater than or equal to 1, and θ _n is when the current number of acquisitions is n, the elevation angle of the conical surface in the spherical coordinate system, i is the preset parameter, the value of i can be any natural number, γ ₁ is _one of the two-dimensional golden division ratio coefficient, and γ ₁ = 0.6823.

In step S103, a spiral trajectory is constructed in the conical surface according to a preset spiral trajectory function, and k-space data is acquired by the magnetic resonance imaging system along the spiral trajectory.

In the embodiment of the present invention, after constructing the conical surface corresponding to the current acquisition number, a spiral trajectory may be constructed on the conical surface according to a preset spiral trajectory function, specifically, according to a two-dimensional golden section scaling coefficient. The initial azimuth of the spiral trajectory in the conical surface in the spherical coordinate system, and then constructing (or drawing) the spiral trajectory on the conical surface according to the initial azimuth and the spiral trajectory function. Among them, the formula for calculating the initial azimuth of the spiral trajectory in the spherical coordinate system is:

其中，

为当当前采集次数为n时，螺旋轨迹在球坐标系中的初始方位角，γ₂为二维黄金分割比例系数之一，且γ₂＝0.4656。在构建螺旋轨迹的同时，由磁选共振成像系统沿着该螺旋轨迹，进行k空间数据的采集，从而完成k空间数据的一次采集。螺旋轨迹函数在此不进行限定，可根据实际条件和需求采用适用于圆锥面采集的三维螺旋轨迹曲线函数。

among them,

For the initial azimuth angle of the spiral trajectory in the spherical coordinate system when the current number of acquisitions is n, γ ₂ is one of the two-dimensional golden section scale coefficients, and γ ₂ = 0.4656. At the same time as constructing the spiral trajectory, the magnetic separation resonance imaging system performs k-space data acquisition along the spiral trajectory, thereby completing one acquisition of k-space data. The spiral trajectory function is not limited here, and a three-dimensional spiral trajectory curve function suitable for cone surface acquisition can be adopted according to actual conditions and requirements.

k_xk_yk_z表示球坐标系，虚线部分为虚拟的球体，以便于更清晰地表示出仰角与初始方位角。As an example, the elevation angle θ _n of the conical surface in the spherical coordinate system and the initial azimuth angle of the spiral trajectory on the conical surface in the spherical coordinate system are given in Fig. 2 .

k _x k _y k _z denotes a spherical coordinate system, and the dotted line portion is a virtual sphere in order to more clearly express the elevation angle and the initial azimuth angle.

In step S104, it is detected whether the current number of acquisitions reaches a preset threshold.

In the embodiment of the present invention, when it is detected that the current number of acquisitions reaches the preset threshold, the collection of the k-space data may be considered to be completed, and step S104 is performed; otherwise, step S105 is performed.

In step S105, the acquisition of the k-space data is stopped, and the acquired k-space data is output.

In the embodiment of the present invention, it is currently considered that the acquisition of k-space data has been completed, and the acquired k-space data is output, and the acquired k-space data can be used to reconstruct a three-dimensional dynamic magnetic resonance image, for example, first to second. The k-space data acquired ten times is used for reconstruction of the first-frame three-dimensional magnetic resonance image, and the k-space data acquired from the twenty-first to thirty-times is used for reconstruction of the second-frame three-dimensional magnetic resonance image, and thus is calculated, that is, The reconstruction of the 3D dynamic magnetic resonance image can be completed, thereby improving the continuity of the reconstructed 3D dynamic magnetic resonance image through continuous acquisition of k-space data.

By way of example, a on the left side of FIG. 3 is a spiral track that is continuously acquired three times, b on the right side is a spiral track that is continuously collected 300 times, and a dotted line portion is a virtual sphere (used to represent a three-dimensional spherical k-space). Figure 4 shows the point distribution of the end of the spiral track on the virtual spherical surface after 500 consecutive acquisitions. As can be seen from Figure 4, the acquired k-space data is approximately evenly distributed in the k-space of the three-dimensional sphere. Figure 5 shows the distribution of the points on the virtual spherical surface at the end of the spiral path under different acquisition times, different time windows and different time combinations. It can be seen from Figure 5 that the k acquired in any length of time (that is, the number of arbitrary acquisitions) The spatial data is approximately evenly distributed in the k-space of the three-dimensional sphere. The k-space data acquired in the time window of any position is approximately evenly distributed in the k-space of the three-dimensional sphere, and the k-space data acquired in any combination time window is in the three-dimensional sphere. Approximate uniform distribution in k-space, which makes the selection of data more convenient in subsequent image reconstruction, effectively improving the data acquisition efficiency of 3D dynamic magnetic resonance imaging and the time resolution of 3D dynamic magnetic resonance images.

In step S106, the current acquisition count is incremented, and the process proceeds to step S102.

In the embodiment of the present invention, when the current number of acquisitions does not reach the preset threshold, the current acquisition times may be added, and the process proceeds to step S102, and the construction of the conical surface and the spiral trajectory corresponding to the current acquisition times is continued. And k-space data collection.

In the embodiment of the present invention, a spherical coordinate system is established in a three-dimensional k-space of a magnetic resonance imaging system, and a conical surface is established according to a two-dimensional golden ratio coefficient in a spherical coordinate system, and a spiral orbit on a conical surface is constructed. Trace, through the magnetic resonance imaging system, the k-space data is collected along the spiral trajectory. When the current acquisition times reach the preset threshold, the acquisition of the k-space data is stopped, and the acquired k-space data is output, otherwise the current acquisition times are added. In one operation, the construction of the conical surface, the spiral trajectory and the acquisition of the k-space data are continued, thereby realizing the continuous acquisition of the three-dimensional k-space data in the three-dimensional dynamic magnetic resonance imaging, so that the data collected in any time window is in the k-space of the three-dimensional sphere. The approximation is evenly distributed, which makes the selection of subsequent image reconstruction data more free, and effectively improves the data collection efficiency of 3D dynamic magnetic resonance imaging and the time resolution of 3D dynamic magnetic resonance images.

Embodiment 2:

FIG. 6 shows a structure of a three-dimensional dynamic magnetic resonance imaging acquisition apparatus according to Embodiment 2 of the present invention. For convenience of description, only parts related to the embodiment of the present invention are shown, including:

The conical surface construction unit 61 is configured to establish a spherical coordinate system in a three-dimensional k-space of the preset magnetic resonance imaging system, and construct a conical surface corresponding to the current acquisition number according to the spherical coordinate system.

In the embodiment of the present invention, the spherical coordinate system is established in the three-dimensional k-space before the magnetic resonance imaging system acquires the k-space data, and the conical surface corresponding to the current acquisition number is established in the spherical coordinate system, specifically, according to the preset The two-dimensional golden section scale coefficient calculates the elevation angle of the conical surface corresponding to the current acquisition number in the spherical coordinate system, and according to the elevation angle, the origin of the spherical coordinate system is the apex of the conical surface, and the conical surface corresponding to the current collection number is constructed. .

In the embodiment of the present invention, the formula for calculating the elevation angle of the conical surface in the spherical coordinate system may be:

θ _n =arcsin(2mod(n ₁ γ ₁ ,1)-1), where n ₁ =n+i, n is the current number of acquisitions, n is a positive integer greater than or equal to 1, and θ _n is when the current number of acquisitions is n, the elevation angle of the conical surface in the spherical coordinate system, i is the preset parameter, the value of i can be any natural number, γ ₁ is _one of the two-dimensional golden division ratio coefficient, and γ ₁ = 0.6823.

The spiral collecting unit 62 is configured to construct a spiral trajectory in the conical surface according to a preset spiral trajectory function, and collect k-space data through the magnetic resonance imaging system along the spiral trajectory.

In the embodiment of the present invention, after constructing the conical surface corresponding to the current acquisition number, a spiral trajectory may be constructed on the conical surface according to a preset spiral trajectory function, specifically, according to the two-dimensional golden section. The proportional coefficient calculates the initial azimuth of the spiral trajectory in the spherical coordinate system in the spherical coordinate system, and then constructs (or draws) the spiral trajectory on the conical surface according to the initial azimuth and the spiral trajectory function. Among them, the formula for calculating the initial azimuth of the spiral trajectory in the spherical coordinate system is:

其中，

为当当前采集次数为n时，螺旋轨迹在球坐标系中的初始方位角，γ₂为二维黄金分割比例系数之一，且γ₂＝0.4656。在构建螺旋轨迹的同时，由磁选共振成像系统沿着该螺旋轨迹，进行k空间数据的采集，从而完成k空间数据的一次采集。螺旋轨迹函数在此不进行限定，可根据实际条件和需求采用适用于圆锥面采集的三维螺旋轨迹曲线函数。

among them,

For the initial azimuth angle of the spiral trajectory in the spherical coordinate system when the current number of acquisitions is n, γ ₂ is one of the two-dimensional golden section scale coefficients, and γ ₂ = 0.4656. At the same time as constructing the spiral trajectory, the magnetic separation resonance imaging system performs k-space data acquisition along the spiral trajectory, thereby completing one acquisition of k-space data. The spiral trajectory function is not limited here, and a three-dimensional spiral trajectory curve function suitable for cone surface acquisition can be adopted according to actual conditions and requirements.

The collection data output unit 63 is configured to stop the acquisition of the k-space data and output the acquired k-space data when the current acquisition times reaches the preset threshold, otherwise, the current acquisition times are added, and the cone surface is triggered. The unit 61 performs an operation of constructing a conical surface corresponding to the current number of acquisitions.

In the embodiment of the present invention, when it is detected that the current number of acquisitions reaches a preset threshold, the k-space data may be collected, and the acquired k-space data may be used to reconstruct a three-dimensional dynamic magnetic resonance image, for example, the first The k-space data acquired from the twentieth time is used for the reconstruction of the first frame of the three-dimensional magnetic resonance image, and the k-space data acquired from the twenty-first to thirty times is used for the reconstruction of the second-frame three-dimensional magnetic resonance image. By this calculation, the reconstruction of the 3D dynamic magnetic resonance image can be completed, and the continuity of the reconstructed 3D dynamic magnetic resonance image is improved by the continuous acquisition of k-space data.

In the embodiment of the present invention, when the current number of acquisitions reaches the collection threshold, the acquired k-space data is approximately evenly distributed in the k-space of the three-dimensional sphere, and is within an arbitrary length of time (ie, an arbitrary number of acquisitions) and an arbitrary position time window. The k-space data collected in any combination time window is approximately evenly distributed in the k-space of the three-dimensional sphere, so that the data selection in the subsequent image reconstruction is more free, and the data of the three-dimensional dynamic magnetic resonance imaging is effectively improved. Acquisition efficiency, time resolution of 3D dynamic magnetic resonance images.

In the embodiment of the present invention, when the current number of acquisitions does not reach the preset threshold, the current acquisition times may be added, and the conical surface construction unit 61 is triggered to perform the conical surface corresponding to the current acquisition times.

Preferably, as shown in FIG. 7, the conical surface building unit 61 comprises:

The elevation angle calculation unit 711 is configured to calculate an elevation angle of the conical surface corresponding to the current acquisition number in the spherical coordinate system according to the preset two-dimensional golden section scale coefficient;

The conical surface construction subunit 712 is configured to construct a conical surface according to the elevation angle of the conical surface in the spherical coordinate system and the origin of the spherical coordinate system as a vertex.

Preferably, the spiral collection unit 62 comprises:

The azimuth calculating unit 721 is configured to calculate an initial azimuth of the spiral trajectory in the spherical coordinate system according to the two-dimensional golden section scaling coefficient;

The trajectory construction unit 722 is configured to construct a spiral trajectory according to an initial azimuth and a spiral trajectory function of the spiral trajectory in the spherical coordinate system.

In the embodiment of the present invention, a spherical coordinate system is established in a three-dimensional k-space of a magnetic resonance imaging system, and a conical surface is established according to a two-dimensional golden section scale coefficient in a spherical coordinate system, and a spiral trajectory on a conical surface is constructed, by magnetic resonance The imaging system performs k-space data acquisition along the spiral trajectory. When the current acquisition times reach the preset threshold, the k-space data acquisition is stopped, and the acquired k-space data is output, otherwise the current acquisition times are added, and the cone is continued. The construction of surface and spiral trajectory and the acquisition of k-space data enable continuous acquisition of 3D k-space data in 3D dynamic magnetic resonance imaging, so that the data collected in any time window is approximately evenly distributed in the k-space of the three-dimensional sphere. Furthermore, the selection of subsequent image reconstruction data is more free, and the data collection efficiency of the three-dimensional dynamic magnetic resonance imaging and the temporal resolution of the three-dimensional dynamic magnetic resonance image are effectively improved.

In the embodiment of the present invention, each unit of the three-dimensional dynamic magnetic resonance imaging acquisition device may be implemented by a corresponding hardware or software unit, and each unit may be an independent software and hardware unit, or may be integrated into a software and hardware unit. It is not intended to limit the invention.

Embodiment 3:

FIG. 8 shows the structure of a medical device according to a third embodiment of the present invention. For the convenience of description, only parts related to the embodiment of the present invention are shown.

The medical device 8 of the embodiment of the present invention includes a processor 80, a memory 81, and is stored in the memory. Computer program 82 in 81 and operable on processor 80. The processor 80, when executing the computer program 82, implements the steps in the above-described method embodiments, such as steps S101 through S106 shown in FIG. Alternatively, processor 80, when executing computer program 82, implements the functions of the various units of the apparatus embodiments described above, such as the functions of units 61-63 shown in FIG.

In the embodiment of the present invention, a spherical coordinate system is established in the k-space of the preset three-dimensional dynamic magnetic resonance imaging system, and a conical surface corresponding to the current acquisition number is constructed according to the spherical coordinate system, and is constructed in the conical surface according to the spiral trajectory function. Spiral trajectory, and k-space data is collected along the spiral trajectory by the magnetic resonance imaging system. When the current number of acquisitions reaches a preset threshold, the acquisition of k-space data is stopped, and the acquired k-space data is output, otherwise the jump To the step of constructing the conical surface, the k-space data acquisition is continued, so that the k-space data is continuously acquired by the spherical coordinates, the conical surface and the spiral trajectory, and an approximately uniform k-space data distribution can be obtained in any acquisition time window, so that The selection of subsequent image reconstruction data is more free, which effectively improves the data collection efficiency of 3D dynamic magnetic resonance imaging and the temporal resolution of 3D dynamic magnetic resonance images obtained by subsequent reconstruction.

Embodiment 4:

In an embodiment of the present invention, there is provided a computer readable storage medium storing a computer program, which when executed by a processor, implements the steps in the foregoing method embodiments, for example, FIG. Steps S101 to S106 are shown. Alternatively, the computer program, when executed by the processor, implements the functions of the various units of the apparatus embodiments described above, such as the functions of units 61 through 63 shown in FIG.

In the embodiment of the present invention, the present invention establishes a spherical coordinate system in the k-space of the preset three-dimensional dynamic magnetic resonance imaging system, and constructs a conical surface corresponding to the current acquisition number according to the spherical coordinate system, according to the spiral trajectory function, in the conical surface A spiral trajectory is constructed, and k-space data is collected along the spiral trajectory by the magnetic resonance imaging system. When the current acquisition number of the detection channel reaches a preset threshold, the acquisition of k-space data is stopped, and the acquired k-space data is output, otherwise the hop is output. Turning to the step of constructing the conical surface, the k-space data acquisition is continued, so that the k-space data is continuously acquired by the spherical coordinates, the conical surface and the spiral trajectory, and the approximate uniform k-space data distribution can be obtained in any acquisition time window. Make subsequent images heavy The choice of data is more free, which effectively improves the data collection efficiency of 3D dynamic magnetic resonance imaging and the temporal resolution of 3D dynamic magnetic resonance images obtained by subsequent reconstruction.

The computer readable storage medium of the embodiments of the present invention may include any entity or device capable of carrying computer program code, a recording medium such as a ROM/RAM, a magnetic disk, an optical disk, a flash memory, or the like.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. Within the scope.

Claims (10)

A method for acquiring three-dimensional dynamic magnetic resonance imaging, characterized in that the method comprises the following steps: Establishing a spherical coordinate system in a three-dimensional k-space of the preset magnetic resonance imaging system, and constructing a conical surface corresponding to the current acquisition number according to the spherical coordinate system; Constructing a spiral trajectory in the conical surface according to a preset spiral trajectory function, and collecting k-space data through the magnetic resonance imaging system along the spiral trajectory; When it is detected that the current number of acquisitions reaches a preset threshold, the collection of the k-space data is stopped, and the collected k-space data is output, otherwise, the current collection times are added, and the operation is jumped to the location. The step of constructing a conical surface corresponding to the current number of acquisitions is described. The method of claim 1 wherein the step of constructing the conical surface corresponding to the current number of acquisitions comprises: Calculating an elevation angle of the conical surface corresponding to the current acquisition number in the spherical coordinate system according to a preset two-dimensional golden section scale coefficient; The conical surface is constructed according to an elevation angle of the conical surface in the spherical coordinate system with an origin of the spherical coordinate system as a vertex. The method of claim 2, wherein the step of constructing a spiral trajectory in the conical surface according to a predetermined spiral trajectory function comprises: Calculating an initial azimuth angle of the spiral trajectory in the spherical coordinate system in the conical surface according to the two-dimensional golden section scale coefficient; The spiral trajectory is constructed based on an initial azimuth of the spiral trajectory in the spherical coordinate system and the spiral trajectory function. The method of claim 3 wherein the initial azimuth of the spiral trajectory in the spherical coordinate system is calculated as:

Where n ₁ = n + i, the n is the current number of acquisitions, and the i is a preset parameter,

The γ ₂ is one of the two-dimensional golden section scale coefficients when the current acquisition number is n, the initial azimuth of the spiral trajectory in the spherical coordinate system. The method of claim 2 wherein the formula for calculating the elevation angle of the conical surface in the spherical coordinate system is: θ _n =arcsin(2mod(n ₁ γ ₁ ,1)-1), where n ₁ =n+i, the i is a preset parameter, the n is the current number of acquisitions, and the θ _n is When the current number of acquisitions is n, the n is a positive integer greater than or equal to 1, the elevation angle of the conical surface in the spherical coordinate system, and the γ ₁ is _one of the two-dimensional golden division ratio coefficients . A three-dimensional dynamic magnetic resonance imaging acquisition device, characterized in that the device comprises: a conical surface building unit, configured to establish a spherical coordinate system in a three-dimensional k-space of the preset magnetic resonance imaging system, and construct a conical surface corresponding to the current acquisition number according to the spherical coordinate system; a spiral collecting unit configured to construct a spiral trajectory in the conical surface according to a preset spiral trajectory function, and collect k-space data through the magnetic resonance imaging system along the spiral trajectory; The collecting data output unit is configured to stop collecting the k-space data when the current number of acquisitions reaches a preset threshold, and output the collected k-space data, otherwise, add the current collection number Operating, and triggering the conical surface building unit to perform an operation of constructing a conical surface corresponding to the current number of acquisitions. The device of claim 6 wherein said conical surface building unit comprises: An elevation calculation unit, configured to calculate an elevation angle of the conical surface corresponding to the current acquisition number in the spherical coordinate system according to a preset two-dimensional golden section scale coefficient; The conical surface building subunit is configured to construct the conical surface according to an elevation angle of the conical surface in the spherical coordinate system with an origin of the spherical coordinate system as a vertex. The device of claim 7 wherein said spiral acquisition unit comprises: An azimuth calculation unit, configured to calculate an initial azimuth of the spiral trajectory in the spherical coordinate system in the conical surface according to the two-dimensional golden section scale coefficient; a trajectory building unit for initial azimuth angles in the spherical coordinate system according to the spiral trajectory The spiral trajectory function constructs the spiral trajectory. A medical device comprising a memory, a processor, and a computer program stored in the memory and operable on the processor, wherein the processor executes the computer program as claimed in claim 1 5 The steps of any of the methods described. A computer readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the steps of the method of any one of claims 1 to 5.

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