Object control method, magnetic resonance imaging system, device and computer equipment

Abstract

The application relates to an object control method, a magnetic resonance imaging system, a device and a computer device. The method comprises: acquiring a return focusing radio frequency pulse generated by a magnetic resonance scanning sequence; determining a control gradient pulse based on relative position information of a ferromagnetic object in a magnetic resonance imaging environment; and controlling the ferromagnetic object to move to a target position by applying the original gradient pulse and the control gradient pulse to the magnetic resonance imaging environment. The method can combine the magnetic resonance image to control the ferromagnetic object to move to the target position, can greatly shorten the interval time of the control force implementation, better integrates the imaging and the motion control, and thus can avoid the invalid motion of the ferromagnetic object, thereby shortening the time length of the ferromagnetic object moving to the target position.

Description

Technical Field

[0001] This application relates to the field of medical technology, and in particular to an object control method, a magnetic resonance imaging system, an apparatus, and a computer device. Background Technology

[0002] Magnetic resonance imaging (MRI) technology has advantages such as high spatial resolution, superior soft tissue contrast, and no ionizing radiation, making it a very important imaging technology in the field of clinical medical auxiliary diagnosis.

[0003] In related technologies, ferromagnetic objects can be used to assist in the clinical application of magnetic resonance imaging. For example, the movement of ferromagnetic objects in a magnetic resonance environment can be used to perform minimally invasive surgery, targeted drug delivery, and other operations.

[0004] However, using related technologies to control the movement of ferromagnetic objects can lead to a long control process. Summary of the Invention

[0005] Therefore, it is necessary to provide an object control method, a magnetic resonance imaging system, an apparatus, and a computer device to address the aforementioned technical problems.

[0006] In a first aspect, embodiments of this application provide an object control method, the method comprising:

[0007] Acquire the refocusing radio frequency pulses generated corresponding to the magnetic resonance scanning sequence;

[0008] Based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment, the control gradient pulse is determined; the control gradient pulse is distributed on both sides of the location of the convergent radio frequency pulse.

[0009] By applying raw gradient pulses and control gradient pulses to the magnetic resonance imaging environment, the movement of a ferromagnetic object to the target position can be controlled.

[0010] In one embodiment, the refocusing radio frequency pulse includes at least one refocusing module; determining the control gradient pulse based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment includes:

[0011] Obtain the relative orientation information of ferromagnetic objects;

[0012] Based on the relative orientation information of the ferromagnetic object and the position of each convergence module, the control gradient block corresponding to each convergence module is determined.

[0013] The control gradient pulse is determined based on the control gradient block corresponding to each convergence module.

[0014] In one embodiment, the relative orientation information includes the distance between the current position of the ferromagnetic object and the target position;

[0015] Based on the relative orientation information of the ferromagnetic object and the position of each convergence module, the control gradient block corresponding to each convergence module is determined, including:

[0016] For any convergence module, the first gradient block and the second gradient block corresponding to the convergence module are determined based on the distance between the current position and the target position of the ferromagnetic object.

[0017] The first gradient block and the second gradient block are defined as the control gradient blocks corresponding to the re-convergence module; wherein the area of ​​the first gradient block is the same as that of the second gradient block, and the first gradient block and the second gradient block are located on both sides of the location of the re-convergence module.

[0018] In one embodiment, determining the first gradient block and the second gradient block corresponding to the convergence module based on the distance between the current position and the target position of the ferromagnetic object includes:

[0019] Obtain the control gradient parameters; the control gradient parameters are determined based on the distance between the current position and the target position of the ferromagnetic object; the control gradient parameters include the size and direction of the gradient block;

[0020] Based on the control gradient parameters, the first gradient block and the second gradient block corresponding to the back-convergence module are determined.

[0021] In one embodiment, obtaining the relative orientation information of the ferromagnetic object includes:

[0022] Obtain the current position and target position of the ferromagnetic object in the magnetic resonance imaging environment;

[0023] The relative orientation information of the ferromagnetic object is determined based on its current position and the target position in the magnetic resonance imaging environment.

[0024] In one embodiment, the convergence module includes an X-direction convergence module, a Y-direction convergence module, and a Z-direction convergence module; the relative orientation information also includes the orientation of the current position of the ferromagnetic object relative to the target position;

[0025] Based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment, the control gradient pulse is determined, including:

[0026] Based on the orientation of the ferromagnetic object relative to the target position, the target direction control gradient pulse corresponding to the target direction convergence module is determined; the target direction convergence module is at least one of the X-direction convergence module, Y-direction convergence module, and Z-direction convergence module.

[0027] The control gradient pulse is determined based on the position of the control gradient pulse and the retraction radio frequency pulse in the target direction.

[0028] In one embodiment, the method further includes:

[0029] Acquire radio frequency signal data of the imaging object in the magnetic resonance imaging environment under the excitation of the magnetic resonance scanning sequence after the application of a control gradient pulse; wherein, the magnetic resonance scanning sequence after the application of the control gradient pulse includes the radio frequency pulse, the original gradient pulse, and the control gradient pulse;

[0030] Magnetic resonance images of the imaging object are generated based on radio frequency signal data.

[0031] Secondly, embodiments of this application provide a magnetic resonance imaging system, which includes: a magnetic resonance imaging device and a computer device; the magnetic resonance imaging device includes a magnet and a gradient coil;

[0032] Magnets are used to generate the main magnetic field in the environment of the object being imaged.

[0033] Gradient coils are used to generate gradient magnetic fields and work together with the main magnet to provide the magnetic resonance imaging environment.

[0034] Computer equipment is used to acquire the reconverging radio frequency pulses generated corresponding to the magnetic resonance scanning sequence, and to determine the control gradient pulses based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment; the control gradient pulses are distributed on both sides of the location of the reconverging radio frequency pulses.

[0035] Magnetic resonance imaging equipment is used to apply raw gradient pulses and control gradient pulses to the magnetic resonance imaging environment to control the movement of ferromagnetic objects to the target position.

[0036] Thirdly, embodiments of this application provide an object control device, the device comprising:

[0037] The recoil pulse acquisition module is used to acquire the recoil radio frequency pulses generated corresponding to the magnetic resonance scanning sequence;

[0038] The control pulse determination module is used to determine the control gradient pulse based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment; the direction of the magnetic field force impulse of the control gradient pulse is the same as the direction of the magnetic field force impulse of the original gradient pulse in the magnetic resonance scanning sequence; the control gradient pulse is distributed on both sides of the location of the refocusing radio frequency pulse.

[0039] The object motion control module is used to control the movement of a ferromagnetic object to the target position by applying raw gradient pulses and control gradient pulses to the magnetic resonance imaging environment.

[0040] Fourthly, embodiments of this application provide a computer device, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of any of the methods described in the first aspect of the embodiments.

[0041] The aforementioned object control method, magnetic resonance imaging system, device, and computer equipment allow the computer equipment to acquire the recoil radio frequency pulses generated corresponding to the magnetic resonance scanning sequence. Based on the relative orientation information of the ferromagnetic object in the magnetic resonance imaging environment, the control gradient pulse is determined. By applying the original gradient pulse and the control gradient pulse to the magnetic resonance imaging environment, the ferromagnetic object is controlled to move to the target position. This method can combine magnetic resonance images to control the movement of the ferromagnetic object to the target position, which can greatly shorten the interval time of control force implementation and better integrate imaging and motion control. This can avoid the situation of ineffective movement of the ferromagnetic object, thereby shortening the time for the ferromagnetic object to move to the target position. Attached Figure Description

[0042] Figure 1 This is a diagram illustrating the application environment of an object control method in one embodiment;

[0043] Figure 2 This is a flowchart illustrating an object control method in one embodiment;

[0044] Figure 3 This is a waveform diagram of an imaging sequence in one embodiment;

[0045] Figure 4 This is a waveform diagram of another imaging sequence in another embodiment;

[0046] Figure 5 This is a waveform diagram of another imaging sequence in another embodiment;

[0047] Figure 6 This is a schematic diagram of a method for determining control gradient pulses based on the relative orientation information of ferromagnetic objects in a magnetic resonance imaging environment, as described in another embodiment.

[0048] Figure 7 This is a flowchart illustrating a method for determining the control gradient block corresponding to each convergence module based on the relative orientation information of the ferromagnetic object and the position of each convergence module in another embodiment.

[0049] Figure 8 This is a flowchart illustrating a method for obtaining the relative orientation information of a ferromagnetic object in another embodiment.

[0050] Figure 9 The waveform diagram of the re-convergence module and gradient block is shown in another embodiment;

[0051] Figure 10 for Figure 4 A schematic diagram of the imaging sequence and the corresponding control gradient pulse in the embodiment;

[0052] Figure 11 for Figure 5A waveform diagram of the imaging sequence and corresponding control gradient pulse in the embodiment;

[0053] Figure 12 for Figure 5 Another waveform diagram of the imaging sequence and corresponding control gradient pulse in the embodiment;

[0054] Figure 13 for Figure 5 Another waveform diagram of the imaging sequence and corresponding control gradient pulse in the embodiment;

[0055] Figure 14 This is a schematic diagram of a method for determining control gradient pulses based on the relative orientation information of ferromagnetic objects in a magnetic resonance imaging environment, as described in another embodiment.

[0056] Figure 15 This is a schematic diagram of magnetic resonance images acquired at three different times in another embodiment;

[0057] Figure 16 This is a structural block diagram of an object control device in one embodiment;

[0058] Figure 17 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0059] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0060] The object control method provided in this application can control the movement of a ferromagnetic object to a lesion point in a medical image, thereby enabling minimally invasive surgery, targeted drug delivery, and other operations. Optionally, this object control method is applicable to... Figure 1 The magnetic resonance imaging (MRI) system shown includes an MRI scanner and a computer. Optionally, the MRI scanner can be a permanent magnet MRI system, a conventional magnetic resonance imaging system, or a superconducting MRI system, etc.; the computer can be a standalone server or a server cluster consisting of multiple servers, and can also be, but is not limited to, various personal computers, laptops, smartphones, tablets, and portable wearable devices. The MRI scanner and the computer can communicate with each other; the communication method can be a wired connection, Wi-Fi, mobile network, or Bluetooth connection, etc. The following embodiments will describe the implementation process of the object control method.

[0061] To control the movement of a ferromagnetic object to a target position in a magnetic resonance imaging environment, embodiments of this application employ an object control method, such as... Figure 2 The diagram shown below illustrates the process of object control. The following examples demonstrate how this method is applied to... Figure 1 Taking a magnetic resonance imaging system as an example, the object control method is explained. This object control method may include the following steps:

[0062] S100: Obtain the re-convergence radio frequency pulses generated corresponding to the magnetic resonance scanning sequence.

[0063] Specifically, the aforementioned magnetic resonance imaging sequences can be spin echo sequences, fast spin echo sequences, gradient echo sequences, inversion recovery sequences, planar echo sequences, angiography sequences, and water imaging sequences, etc., and of course, other sequences as well.

[0064] It should be noted that the main magnetic field generated by the magnet in the magnetic resonance imaging (MRI) device and the gradient magnetic field generated by the gradient coil in the MRI device work together to form the MRI environment. Furthermore, as the ferromagnetic object moves from its current position to the target position, the MRI device can continuously acquire MRI scan sequences and apply these sequences to the MRI environment. Simultaneously, the radio frequency (RF) coil in the MRI device can periodically generate a series of RF pulses. Each cycle of RF pulses can include an excitation RF pulse with a 90° flip angle and multiple convergence RF pulses with a 180° flip angle. Optionally, the convergence RF pulse can be understood as the RF pulse that performs the convergence function.

[0065] In the embodiments of this application, the generated excitation RF pulse may have a flip angle other than 90°, such as any flip angle between 0° and 180°; the flip angle of the generated retraction RF pulse may be other than 180°; however, the flip angle of the different generated excitation RF pulses is the same.

[0066] For example, such as Figure 3 The image shown is a schematic diagram of the waveform of the imaging sequence generated when the magnetic resonance scanning sequence is a fast spin echo sequence. Figure 3 The diagram shows the waveforms of the generated radio frequency (RF) signal and the original gradient pulse in three different directions in three-dimensional space. These three different directions are the X, Y, and Z directions. Figure 3 In the diagram, GS represents the Z direction, GP represents the Y direction, GR represents the X direction, the horizontal axis represents the imaging coordinate axes in three different directions, the trapezoids on the upper and lower sides of the horizontal axis represent the original gradient pulse waveforms in three different directions, and the dashed lines perpendicular to the horizontal axis represent the position of the retraction RF pulse's flip angle within the RF pulse.

[0067] like Figure 4 The image shows the waveforms of the radio frequency (RF) signal and the original gradient pulse in three different directions in three-dimensional space when the magnetic resonance scanning sequence is a spin echo sequence. Figure 4 The horizontal axis in the image represents the imaging coordinate axis, and the trapezoids and triangles on both sides of the horizontal axis represent pulse waveforms.

[0068] In addition, during magnetic resonance imaging (MRI), degraded gradient pulses may be introduced to eliminate the influence of the attenuated signal from free induction on MRI. Figure 5 The image shown is in Figure 3 Based on the waveforms of the imaging sequence, waveforms of damaged gradient pulses were added to both sides of the original gradient blocks in three different directions. Figure 5 The waveform at the location indicated by the arrow is the damaged gradient pulse.

[0069] Understandably, given the different flip angles of the excitation and retraction radio frequency (RF) pulses, the computer equipment in a magnetic resonance imaging (MRI) system can extract the retraction RF pulse from the excitation and retraction RF pulses generated corresponding to the MRI scan sequence. Furthermore, the aforementioned retraction RF pulse can also be a user-defined RF pulse. In particular, the retraction RF pulse can play an imaging resistance role in non-uniform field imaging of MRI.

[0070] S200. Based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment, determine the control gradient pulse; the control gradient pulse is distributed on both sides of the location of the refocusing radio frequency pulse.

[0071] In this process, the ferromagnetic object moves across the surface of the imaging subject due to the action of pulses. The magnetic resonance image generated during the movement of the ferromagnetic object from its current position to the target position can include an image of the region where the ferromagnetic object is located. Optionally, the magnetic resonance image can be an image of any tissue part of the imaging subject.

[0072] Specifically, the computer equipment in a magnetic resonance imaging (MRI) system can acquire magnetic resonance images of a ferromagnetic object during its movement, preprocess the images, and then analyze and process the preprocessed images to determine the relative orientation information of the ferromagnetic object in the magnetic resonance image; alternatively, it can directly analyze and process the magnetic resonance image to determine the relative orientation information of the ferromagnetic object in the magnetic resonance image. Optionally, the above preprocessing can be noise reduction processing, image segmentation processing, and / or image enhancement processing, etc. Optionally, the above analysis and processing can be a process of analyzing pixels, feature points, and / or contour points in the image, etc.

[0073] Optionally, the relative orientation information of the ferromagnetic object can be the relative orientation information of the ferromagnetic object with respect to the lesion point, target point, or target location in the magnetic resonance image. Optionally, the control gradient pulse can be distributed on both sides of the location of the reconverging radiofrequency pulse, that is, on both sides of the location of the flip angle of the reconverging radiofrequency pulse.

[0074] It should be noted that the time range of the control gradient pulse may include the time range of the reconverging RF pulse; or, the time range of the control gradient pulse may not include the time range of the reconverging RF pulse, and the time range of the control gradient pulse may be located on both sides of the time range of the reconverging RF pulse.

[0075] It is understandable that, among all the convergent radio frequency pulses generated during the process of a ferromagnetic object moving from its current position to its target position, control gradient pulses can be distributed on both sides of the position of each convergent radio frequency pulse; or, control gradient pulses can be distributed on both sides of the position of some convergent radio frequency pulses, while control gradient pulses can not be distributed on both sides of the position of other convergent radio frequency pulses.

[0076] S300 controls the movement of a ferromagnetic object to the target position by applying a raw gradient pulse and a control gradient pulse to the magnetic resonance imaging environment.

[0077] Specifically, the original gradient pulse can be the gradient pulse generated by the gradient coil in the magnetic resonance imaging device under normal conditions. Optionally, the control gradient pulse can be an additional gradient pulse applied to the magnetic resonance imaging environment on the basis of the original gradient pulse, so as to control the movement of the ferromagnetic object to the target position by the combined action of the control gradient pulse and the original gradient pulse.

[0078] It is understandable that the magnetic resonance imaging equipment in the magnetic resonance imaging system can directly receive the user's input request for the application of control gradient pulses, and after responding to the request, apply the control gradient pulses to the magnetic resonance imaging environment. That is, the control gradient pulses and the original gradient pulses are combined to obtain combined gradient pulses, so as to control the movement of ferromagnetic objects to the target position.

[0079] Alternatively, the computer equipment in the magnetic resonance imaging (MRI) system can receive a control gradient application command input by the user and, in response, send a control gradient application request carrying a control gradient pulse to the MRI equipment. The MRI equipment, upon responding to the control gradient application request, applies the control gradient pulse to the MRI environment. In this configuration, the computer equipment can generate the corresponding control gradient application request after receiving the control gradient application command.

[0080] It should be noted that the input method for controlling gradient application commands can be mouse, keyboard, voice, gestures, etc. Optionally, the timing of inputting the control gradient application command can be determined by the doctor or operator. The command can be input at any time according to the movement requirements of the ferromagnetic object, and there is no time limit. Optionally, the target location can be any location within the imaging object.

[0081] Optionally, the control gradient application request may also carry an identifier for the control gradient block, which indicates the specific location where the control gradient block is applied. Optionally, the combination of the control gradient pulse and the original gradient pulse can be understood as superimposing the control gradient pulses and / or the original gradient pulses corresponding to different times to obtain the combined gradient pulses corresponding to different times.

[0082] In this embodiment, since the control gradient pulse applied to the magnetic resonance imaging environment is located on both sides of the convergence radio frequency pulse, the combined action of the control gradient pulse and the original gradient pulse can ensure an increase in the magnetic field effect of the magnetic resonance imaging environment on the ferromagnetic object, thereby controlling the ferromagnetic object to move to the target position.

[0083] In the process of a ferromagnetic object moving from its current position to its target position, magnetic resonance images of the object can be continuously acquired, and the relative orientation information of the ferromagnetic object in the magnetic resonance images can be used to determine whether the ferromagnetic object has moved to the target position.

[0084] Understandably, in a magnetic resonance imaging (MRI) environment, the actual gradient pulse G_Total generated at each moment can be equal to the sum of the original gradient pulse G_Img and the control gradient pulse G_Ctrl at each moment. If at a certain moment, the pulse signals of the original gradient pulse G_Img in the X, Y, and Z directions in three-dimensional space are (Gx_I, Gy_I, Gz_I), and the pulse signals of the control gradient pulse G_Ctrl in the X, Y, and Z directions in three-dimensional space are (Gx_C, Gy_C, Gz_C), then the pulse signals of the actual gradient pulse G_Total generated at that moment in the X, Y, and Z directions in three-dimensional space can be (Gx_I + Gx_C, Gy_I + Gy_C, Gz_I + Gz_C).

[0085] In the object control method provided in this application embodiment, the magnetic resonance imaging system can acquire the recoil radio frequency pulses generated corresponding to the magnetic resonance scanning sequence. Based on the relative orientation information of the ferromagnetic object in the magnetic resonance imaging environment, a control gradient pulse is determined. By applying the original gradient pulse and the control gradient pulse to the magnetic resonance imaging environment, the ferromagnetic object is controlled to move to the target position. This method can apply the control gradient pulse to the magnetic resonance imaging environment based on the original gradient pulse, and apply the control gradient pulse to both sides of the original gradient pulse location, thereby increasing the magnetic field effect of the magnetic resonance imaging environment on the ferromagnetic object to control the ferromagnetic object to move to the target position. In order to enable the ferromagnetic object to move to the ideal target position, applying the control gradient pulse to the magnetic resonance imaging process can increase the controllability of the ferromagnetic object. At the same time, this method can combine the magnetic resonance image to control the ferromagnetic object to move to the target position, which can greatly shorten the interval time of control force implementation and better integrate imaging and motion control. This can avoid the situation of ineffective movement of the ferromagnetic object, thereby shortening the time for the ferromagnetic object to move to the target position.

[0086] In one embodiment, the aforementioned reconvergence radio frequency pulse includes at least one reconvergence module; such as Figure 6 As shown, the step of determining the control gradient pulse based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment in S200 above may include:

[0087] S210. Obtain the relative orientation information of the ferromagnetic object.

[0088] Specifically, computer equipment can use algorithms such as R-CNN, SPP-Net, Fast R-CNN, Faster R-CNN and R-FCN to perform target detection and / or localization analysis on magnetic resonance images to determine the relative orientation information of ferromagnetic objects in the magnetic resonance images.

[0089] S220. Based on the relative orientation information of the ferromagnetic object and the position of each convergence module, determine the control gradient block corresponding to each convergence module.

[0090] Specifically, the aforementioned control gradient block may include the direction of the magnetic force impulse of the control gradient block and the magnitude of the magnetic force impulse of the control gradient block.

[0091] It should be noted that the computer equipment can determine the magnitude of the magnetic force impulse of the control gradient block by performing orientation information conversion, information transfer, and feature extraction through the relative orientation information of the ferromagnetic object. Furthermore, the direction of the magnetic force impulse of the control gradient block can be determined by the position of each convergence module.

[0092] It can also be understood that computer equipment can determine the control gradient pulse by performing orientation information conversion, information transfer, and feature extraction on the relative orientation information of the ferromagnetic object. Optionally, the above orientation information conversion process can be understood as the process of performing arithmetic operations on the relative orientation information of the ferromagnetic object; the above information transfer process can be understood as the process of introducing the relative orientation information of the ferromagnetic object into the relationship between the relative orientation information and the control gradient pulse to obtain the control gradient pulse; the above feature extraction process can be understood as the process of extracting orientation features from the relative orientation information of the ferromagnetic object and determining the control gradient pulse based on the orientation features.

[0093] In the embodiments of this application, each reconvergence module has a corresponding control gradient block; or, in the reconvergence RF pulse, some reconvergence modules have corresponding control gradient blocks, while others may not have corresponding control gradient blocks. Optionally, one reconvergence module may correspond to one or more control gradient blocks.

[0094] Optionally, if a convergence module corresponds to a control gradient block, the time range of the control gradient block can include the time range of the convergence module; that is, the minimum time value corresponding to the time range of the control gradient block is less than the minimum time value corresponding to the time range of the convergence module, and the maximum time value corresponding to the time range of the control gradient block is greater than the maximum time value corresponding to the time range of the convergence module.

[0095] Optionally, if a convergence module corresponds to multiple control gradient blocks, the maximum time range encompassing these multiple control gradient blocks can include the time range of the convergence module; that is, the minimum time value corresponding to the maximum time range encompassing these multiple control gradient blocks is less than the minimum time value corresponding to the time range of the convergence module, and the maximum time value corresponding to the maximum time range encompassing these multiple control gradient blocks is greater than the maximum time value corresponding to the time range of the convergence module. Furthermore, among the multiple control gradient blocks corresponding to a convergence module, different control gradient blocks can correspond to different sub-time ranges, and these different sub-time ranges are located within the maximum time range encompassing these multiple control gradient blocks.

[0096] For example, if a convergence module 1 corresponds to 3 control gradient blocks, namely control gradient block 1, control gradient block 2 and control gradient block 3, and the time range of control gradient block 1 is (1, 2), the time range of control gradient block 2 is (3, 4) and the time range of control gradient block 3 is (5, 6), then the maximum time range of these 3 control gradient blocks combined is (1, 6), and the time range of convergence module 1 can be any range within (1, 6).

[0097] S230. Determine the control gradient pulse based on the control gradient block corresponding to each convergence module.

[0098] Specifically, the computer device can combine the control gradient blocks corresponding to each convergence module to obtain control gradient pulses. Each control gradient block has a corresponding time range on the time axis. Optionally, the time ranges of control gradient blocks corresponding to different convergence modules do not overlap.

[0099] Continuing with the previous example, the three control gradient blocks corresponding to the convergence module 1 are combined, and the final control gradient pulses are control gradient block 1 corresponding to the time range of (1,2), control gradient block 2 corresponding to the time range of (3,4), and control gradient block 3 corresponding to the time range of (5,6) on the time axis; there are no control gradient blocks in the time ranges of (2,3) and (4,5).

[0100] The object control method provided in this application can acquire the relative orientation information of a ferromagnetic object, determine the control gradient block corresponding to each convergence module based on the relative orientation information of the ferromagnetic object and the position of each convergence module, and determine the control gradient pulse based on the control gradient block corresponding to each convergence module. This method can determine the control gradient pulse in real time based on the relative orientation information of the ferromagnetic object acquired in the magnetic resonance image, and further apply the control gradient pulse to the magnetic resonance imaging environment to increase the magnetic field effect on the ferromagnetic object to control the ferromagnetic object to move from the current position to the target position. This can avoid the situation of the ferromagnetic object having invalid movement, can greatly shorten the interval time of control force implementation, better fuse imaging and motion control, and can also shorten the control time of the ferromagnetic object moving from the current position to the target position.

[0101] In one embodiment, the relative orientation information of the ferromagnetic object includes the distance between the current position of the ferromagnetic object and the target position; such as Figure 7 As shown, the step in S220 above, which determines the control gradient block corresponding to each convergence module based on the relative orientation information of the ferromagnetic object and the position of each convergence module, can be achieved through the following steps:

[0102] S221. For any convergence module, determine the first gradient block and the second gradient block corresponding to the convergence module based on the distance between the current position and the target position of the ferromagnetic object.

[0103] Specifically, the computer device can acquire the current position and target position of a ferromagnetic object in a magnetic resonance image. Optionally, since the magnetic resonance image is a two-dimensional image, the current position and target position of the ferromagnetic object acquired based on the magnetic resonance image can both be two-dimensional coordinates.

[0104] Furthermore, the computer device can employ algorithms such as Euclidean distance, Manhattan distance, and Chebyshev distance to calculate the distance between the current position and the target position of the ferromagnetic object in two-dimensional space based on the acquired current and target positions. Then, it searches for information items in the information database that match the distance and identifies one or two gradient blocks from these information items as the first and second gradient blocks corresponding to the convergence module. Optionally, the information database can include multiple information items, each containing the distance between the current and target positions of the ferromagnetic object and one or two corresponding gradient blocks.

[0105] In another embodiment, such as Figure 8 As shown, the step of obtaining the relative orientation information of the ferromagnetic object in S210 above includes:

[0106] S211. Obtain the current position and target position of the ferromagnetic object in the magnetic resonance imaging environment.

[0107] Specifically, the computer device can first perform three-dimensional reconstruction based on the magnetic resonance image to obtain a three-dimensional model corresponding to the imaging object. Then, it can extract feature points from the magnetic resonance image and the three-dimensional model respectively, and match the feature points of the magnetic resonance image and the three-dimensional model based on the feature points of the magnetic resonance image and the three-dimensional model. After that, it can map the current position of the ferromagnetic object and the target position into the three-dimensional model to obtain the three-dimensional coordinates corresponding to the current position and the target position of the ferromagnetic object.

[0108] S212. Determine the relative orientation information of the ferromagnetic object based on its current position and target position in the magnetic resonance imaging environment.

[0109] Understandably, computer devices can employ algorithms such as Euclidean distance, Manhattan distance, and Chebyshev distance to calculate the distance between the current position and the target position of the ferromagnetic object based on their corresponding three-dimensional coordinates. Optionally, this distance can be the distance between the current position and the target position of the ferromagnetic object in three-dimensional space.

[0110] In this embodiment, to control the movement of the ferromagnetic object to the target position and maintain the imaging result unchanged during the movement, gradient blocks, namely a first gradient block and a second gradient block, need to be added on both sides of the location of the convergence module. Specifically, the computer device can determine the area of ​​the gradient block and the direction of the magnetic impulse of the gradient block based on the distance between the current position and the target position of the ferromagnetic object in three-dimensional space. When the distance is large, the determined area of ​​the gradient block is large; when the distance is small, the determined area of ​​the gradient block is small.

[0111] S222. The first gradient block and the second gradient block are determined as the control gradient blocks corresponding to the re-convergence module; wherein the area of ​​the first gradient block is the same as that of the second gradient block, and the first gradient block and the second gradient block are located on both sides of the location of the re-convergence module.

[0112] In this embodiment, each convergence module has a corresponding control gradient block, and each control gradient block includes two gradient blocks, namely a first gradient block and a second gradient block. Optionally, the time range of the first gradient block and the time range of the second gradient block neither overlap nor are connected; that is, there is a certain time interval between the time range of the first gradient block and the time range of the second gradient block.

[0113] In this method, two gradient blocks of the same size and orientation are added on either side of the location of the convergence module, thus minimizing their impact on the magnetic resonance imaging results. Therefore, to minimize the impact of ferromagnetic objects on the imaging results during movement, the area of ​​the first gradient block can be set to be the same as that of the second gradient block, and the first and second gradient blocks can be added to either side of the location of the convergence module. That is, the time range containing the first and second gradient blocks is located on either side of the center time point of the convergence module's time range. Optionally, the direction of the magnetic impulse of the first gradient block is the same as that of the second gradient block.

[0114] For example, Figure 9 The waveform diagrams of the convergence module and its two corresponding gradient blocks are shown, namely the first gradient block and the second gradient block. The area of ​​the first gradient block is the same as that of the second gradient block, and the first gradient block and the second gradient block are located on both sides of the position of the convergence module.

[0115] Alternatively, if for Figure 4 Each 180° convergence module in the process is configured with a corresponding control gradient block. Figure 10 It shows Figure 4 A waveform diagram of the imaging sequence and control gradient pulses. Additionally, if... Figure 5 If a corresponding control gradient block is set for each 180° convergence module, then... Figure 11 It shows Figure 5 A waveform diagram of the imaging sequence and control gradient pulses in the image shows that the size and direction of the control gradient block are the same for each 180° convergence module; if for Figure 5 If one of the 180° convergence modules is configured with a corresponding control gradient block, then... Figure 12 It shows Figure 5 A waveform diagram of the imaging sequence and control gradient pulse; if for Figure 5If a corresponding control gradient block is set for each 180° convergence module, then... Figure 13 It shows Figure 5 The image sequence and control gradient pulses are shown in a waveform diagram, which illustrates the different sizes and orientations of the control gradient blocks corresponding to different 180° refocusing modules.

[0116] The object control method provided in this application can determine the first gradient block and the second gradient block corresponding to any convergence module based on the distance between the current position and the target position of the ferromagnetic object. The first gradient block and the second gradient block with the same area, located on both sides of the position of the convergence module, are determined as the control gradient block corresponding to the convergence module. This method can not only control the ferromagnetic object to move to the target position, but also keep the imaging result unchanged during the movement of the ferromagnetic object. Furthermore, it can shorten the control time for the ferromagnetic object to move from the current position to the target position, so that the ferromagnetic object can move from the current position to the target position quickly. At the same time, the control gradient pulse generated by this method is located on both sides of the position of the convergence module, so it will not affect the imaging result, thereby accurately obtaining the location of the lesion point of the imaging object.

[0117] The following describes how to determine the two gradient blocks corresponding to the convergence module. In one embodiment, the step in S221 above, which determines the first and second gradient blocks corresponding to the convergence module based on the distance between the current position and the target position of the ferromagnetic object, can be implemented through the following steps: obtaining control gradient parameters, and determining the first and second gradient blocks corresponding to the convergence module based on the control gradient parameters. The control gradient parameters are determined based on the distance between the current position and the target position of the ferromagnetic object; the control gradient parameters include the size and direction of the gradient blocks.

[0118] Specifically, the computer device can look up the corresponding information with the same interval distance between the current position and the target position of the ferromagnetic object in three-dimensional space in the mapping relationship, and then determine the control gradient parameters based on the corresponding information. Optionally, the mapping relationship stores multiple corresponding information; each corresponding information includes the interval distance between the current position and the target position of the ferromagnetic object in three-dimensional space and the corresponding control gradient parameters. The control gradient parameters in the mapping relationship correspond one-to-one with the interval distance between the current position and the target position of the ferromagnetic object.

[0119] In addition, the computer device can also receive control gradient parameters input by doctors or other staff. Optionally, doctors or other staff can determine the control gradient parameters based on the distance between the current position and the target position of the ferromagnetic object in three-dimensional space. Optionally, the input method for the control gradient parameters can be mouse, keyboard, voice, gesture, etc.

[0120] The size of the gradient block in the control gradient parameters can include the width and height of the gradient block, as well as the start and end times of the gradient block. Optionally, the total number of control gradient parameters can be equal to the total number of control gradient pulses; the control gradient parameters corresponding to different control gradient pulses can be the same or different. Optionally, the width of the gradient block can be understood as the duration of applying the gradient block to the magnetic resonance imaging environment, and the height of the gradient block can be understood as the intensity of applying the gradient block to the magnetic resonance imaging environment.

[0121] It is understandable that the computer equipment can determine the first gradient block and the second gradient block corresponding to the re-convergence module based on each control gradient parameter.

[0122] The object control method provided in this application embodiment can determine the first gradient block and the second gradient block on both sides of the position of any convergence module, so that these gradient blocks work together to not only control the ferromagnetic object to move to the target position, but also keep the imaging result unchanged during the movement of the ferromagnetic object. Furthermore, it can shorten the control time for the ferromagnetic object to move from the current position to the target position.

[0123] Typically, magnetic resonance imaging (MRI) takes place in a three-dimensional space. Therefore, to add more precise control gradient pulses, corresponding control gradient pulses can be added in each of the three dimensions. Based on this, in one embodiment, the aforementioned convergence module includes an X-direction convergence module, a Y-direction convergence module, and a Z-direction convergence module; the relative orientation information also includes the orientation of the current position of the ferromagnetic object relative to the target position.

[0124] Then as Figure 14 As shown, the step in S200 above, which determines the control gradient pulse based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment, can be achieved through the following steps:

[0125] S240. Based on the orientation of the ferromagnetic object relative to the target position, determine the target direction control gradient pulse corresponding to the target direction convergence module. The target direction convergence module is at least one of the X-direction convergence module, the Y-direction convergence module, and the Z-direction convergence module.

[0126] Specifically, the computer equipment can use the sine theorem, cosine theorem, tangent theorem, and / or antitangent theorem, etc., to calculate the orientation of the ferromagnetic object's current position relative to the target position in three-dimensional space based on the three-dimensional coordinates corresponding to the current position of the ferromagnetic object and the target position. Furthermore, it determines the target direction control gradient pulse corresponding to the target direction gradient pulse based on the orientation of the ferromagnetic object's current position relative to the target position in three-dimensional space. Optionally, the target direction can be the X, Y, and Z directions in a three-dimensional coordinate system.

[0127] The control gradient pulses corresponding to any convergence module can be distributed in at least one of the X, Y, and Z directions. Therefore, the convergence module can include an X-direction convergence module, a Y-direction convergence module, and a Z-direction convergence module; the target direction convergence module can be at least one of the X-direction convergence module, the Y-direction convergence module, and the Z-direction convergence module.

[0128] S250. Determine the control gradient pulse based on the position of the target direction control gradient pulse and the recoil radio frequency pulse.

[0129] Specifically, the position of the control gradient pulse can be determined based on the position of the re-convergence module. The computer device can determine the position of the target direction control gradient pulse corresponding to the target direction re-convergence module based on the target direction control gradient pulse and the position of the target direction re-convergence module in the re-convergence radio frequency pulse. Then, it combines the X-direction re-convergence modules, Y-direction re-convergence modules, and / or Z-direction re-convergence modules in the three-dimensional coordinate system at different times to obtain the control gradient pulse corresponding to the current re-convergence module.

[0130] For the same convergence module, the corresponding X-direction convergence module, Y-direction convergence module, and Z-direction convergence module may be the same or different.

[0131] In addition, in order to apply better control force to the ferromagnetic object, the embodiments of this application can determine the optimal control gradient parameters based on the distance between the current position of the ferromagnetic object and the target position and the orientation of the current position of the ferromagnetic object relative to the target position, and further determine the optimal gradient block corresponding to the convergence module based on the optimal control gradient parameters.

[0132] The object control method provided in this application embodiment can determine the target direction control gradient pulse corresponding to the target direction convergence module based on the orientation of the current position of the ferromagnetic object relative to the target position, and determine the control gradient pulse based on the position of the target direction control gradient pulse and the convergence radio frequency pulse. This method can acquire the control gradient pulse in three dimensions and further add the control gradient pulse in three dimensions to the magnetic resonance imaging environment to accurately control the movement direction of the ferromagnetic object, avoid the situation of the ferromagnetic object having invalid movement, and thus shorten the time for the ferromagnetic object to move to the target position.

[0133] In one embodiment, the object control method further includes the following steps: acquiring radio frequency signal data generated by the imaging object in the magnetic resonance imaging environment under the excitation of a magnetic resonance scanning sequence after the application of a control gradient pulse, and generating a magnetic resonance image of the imaging object based on the radio frequency signal data. The magnetic resonance scanning sequence after the application of the control gradient pulse includes a radio frequency pulse, an original gradient pulse, and a control gradient pulse.

[0134] Specifically, the aforementioned magnetic resonance scanning sequence may include radio frequency pulses, original gradient pulses, and control gradient pulses; the radio frequency pulses may include excitation radio frequency pulses and refocusing radio frequency pulses.

[0135] It should be noted that after applying a control gradient pulse in the magnetic field imaging environment where the imaging object is located, the combined effect of the radio frequency pulse, the original gradient pulse, and the control gradient pulse on the imaging object excites the protons in the imaging object to resonate. At this time, the magnetic resonance imaging device can acquire the radio frequency signal data generated by the imaging object.

[0136] Furthermore, the magnetic resonance imaging (MRI) device can send the radio frequency signal data generated by the acquired imaging object to a computer device, which then performs image reconstruction on the radio frequency signal data to obtain a magnetic resonance image.

[0137] In the magnetic resonance imaging environment, after applying control gradient pulses, the computer equipment can continuously acquire magnetic resonance images. At the same time, it performs target detection and / or localization analysis on each acquired magnetic resonance image to determine the relative orientation information of ferromagnetic objects in each magnetic resonance image, thereby determining whether the ferromagnetic object has moved to the target position based on the relative orientation information of the ferromagnetic object.

[0138] For example, such as Figure 15 The image shows magnetic resonance (MRI) images acquired at three different times (t1, t2, and t3) when the MRI scan sequence is a spin echo sequence. The missing portion of the circular water model in the image represents the location of the ferromagnetic object. After applying a control gradient pulse, the ferromagnetic object can move along the circular water model, so the missing portion of the circular water model differs in the MRI images acquired at different times. This allows the location of the ferromagnetic object to be captured from the MRI images for real-time monitoring.

[0139] Furthermore, this embodiment integrates external control with imaging technology, enabling the error between control and imaging feedback to be at the millisecond level, thus significantly increasing the controllability of ferromagnetic objects. Optionally, external control can be understood as the magnetic field generated by an externally applied control gradient pulse.

[0140] Meanwhile, in this embodiment, since the time interval for acquiring radio frequency signal data can be between 5 and 10 milliseconds, the response time of applying the control gradient pulse to the magnetic resonance imaging environment can also be reduced to the millisecond level.

[0141] The object control method provided in this application embodiment can continuously acquire magnetic resonance images after applying control gradient pulses in the magnetic resonance imaging environment, and monitor whether the ferromagnetic object has moved to the target position based on the real-time acquired magnetic resonance images, thereby enabling accurate positioning of the target position of the imaging object.

[0142] See also Figure 1 As shown, another embodiment provides a magnetic resonance imaging system, which includes: a magnetic resonance imaging device and a computer device; the magnetic resonance imaging device includes a magnet and a gradient coil;

[0143] Magnets are used to generate the main magnetic field in the environment of the object being imaged.

[0144] Gradient coils are used to generate gradient magnetic fields and work together with the main magnet to provide the magnetic resonance imaging environment.

[0145] Computer equipment is used to acquire the reconverging radio frequency pulses generated corresponding to the magnetic resonance scanning sequence, and to determine the control gradient pulses based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment; the control gradient pulses are distributed on both sides of the location of the reconverging radio frequency pulses.

[0146] Magnetic resonance imaging equipment is used to apply raw gradient pulses and control gradient pulses to the magnetic resonance imaging environment to control the movement of ferromagnetic objects to the target position.

[0147] Specifically, after the magnet in the magnetic resonance imaging (MRI) device generates the main magnetic field, it can align the spins of the magnetic nuclei within the object being imaged. Optionally, the magnet can be a superconducting magnet, a permanent magnet, and / or a resistive electromagnet, etc. Simultaneously, the gradient coil in the MRI device can generate a gradient magnetic field, which, together with the main magnet, provides the MRI environment, facilitating imaging encoding.

[0148] It should be noted that the magnetic resonance imaging (MRI) device also includes a radio frequency (RF) coil, and the gradient coil and RF coil are housed within the magnet. The RF coil is used to transmit radio frequency pulses to the target area of ​​the imaging subject in the MRI environment to excite protons within the subject to resonate and acquire the subject's radio frequency signal data.

[0149] Understandably, since the object being imaged contains atomic nuclei with an odd number of protons, such as hydrogen nuclei, these protons have spin motion, similar to small magnets. The spin axes of these small magnets are not fixed; if an external magnetic field is applied, these small magnets will rearrange themselves according to the magnetic field lines, specifically in two directions: parallel to or antiparallel to the magnetic field lines. The direction parallel to the magnetic field lines is called the positive longitudinal axis, and the direction antiparallel to the magnetic field lines is called the negative longitudinal axis. When a radio frequency pulse excites the proton nuclei within the object being imaged, the spin axes of these nuclei deviate from the positive or negative longitudinal axis, thus producing resonance.

[0150] Furthermore, in the magnetic resonance imaging environment, the radio frequency coil in the magnetic resonance imaging device can emit radio frequency pulses to the target part of the imaging object. After the radio frequency coil stops emitting radio frequency pulses, the excited atomic nuclei emit radio frequency signal data, gradually releasing the absorbed energy in the form of electromagnetic waves. The phase and energy level of the radio frequency signal data are the same as the phase and energy level of the radio frequency pulse before excitation.

[0151] In this process, after the atomic nuclei of protons in the imaging object resonate, the magnetic resonance imaging device can acquire radio frequency signal data and send the radio frequency signal data to the computer device. The computer device then performs preprocessing, comparison processing, conversion processing, analysis processing and / or computation processing on the radio frequency signal data to generate a magnetic resonance image.

[0152] The magnetic resonance imaging system provided in this embodiment can execute the above-described method embodiments, and its implementation principle and technical effect are similar, so they will not be described again here.

[0153] In one embodiment, the refocusing radio frequency pulse includes at least one refocusing module; the computer device is specifically used to acquire the relative orientation information of the ferromagnetic object, determine the control gradient block corresponding to each refocusing module based on the relative orientation information of the ferromagnetic object and the position of each refocusing module, and determine the control gradient pulse based on the control gradient block corresponding to each refocusing module.

[0154] The magnetic resonance imaging system provided in this embodiment can execute the above-described method embodiments, and its implementation principle and technical effect are similar, so they will not be described again here.

[0155] In one embodiment, the relative orientation information includes the distance between the current position of the ferromagnetic object and the target position;

[0156] Specifically, the computer device is used to determine the first gradient block and the second gradient block corresponding to any given convergence module based on the distance between the current position and the target position of the ferromagnetic object, and to define the first gradient block and the second gradient block as the control gradient block corresponding to the convergence module; wherein, the area of ​​the first gradient block is the same as that of the second gradient block, and the first gradient block and the second gradient block are located on both sides of the position of the convergence module.

[0157] The magnetic resonance imaging system provided in this embodiment can execute the above-described method embodiments, and its implementation principle and technical effect are similar, so they will not be described again here.

[0158] In one embodiment, the computer device is specifically used to acquire control gradient parameters and determine a first gradient block and a second gradient block corresponding to the convergence module based on the control gradient parameters. The control gradient parameters are determined according to the interval distance between the current position and the target position of the ferromagnetic object, and include the size and direction of the gradient block.

[0159] The magnetic resonance imaging system provided in this embodiment can execute the above-described method embodiments, and its implementation principle and technical effect are similar, so they will not be described again here.

[0160] In one embodiment, the computer device is specifically used to acquire the current position and target position of the ferromagnetic object in the magnetic resonance imaging environment, and to determine the relative orientation information of the ferromagnetic object based on the current position and target position of the ferromagnetic object in the magnetic resonance imaging environment.

[0161] The magnetic resonance imaging system provided in this embodiment can execute the above-described method embodiments, and its implementation principle and technical effect are similar, so they will not be described again here.

[0162] In one embodiment, the convergence module includes an X-direction convergence module, a Y-direction convergence module, and a Z-direction convergence module; the relative orientation information also includes the orientation of the current position of the ferromagnetic object relative to the target position;

[0163] The computer device is specifically used to determine the target direction control gradient pulse corresponding to the target direction convergence module based on the orientation of the current position of the ferromagnetic object relative to the target position, and to determine the control gradient pulse based on the position of the target direction control gradient pulse and the convergence radio frequency pulse; the target direction convergence module is at least one of the X-direction convergence module, the Y-direction convergence module and the Z-direction convergence module.

[0164] The magnetic resonance imaging system provided in this embodiment can execute the above-described method embodiments, and its implementation principle and technical effect are similar, so they will not be described again here.

[0165] In one embodiment, the computer device is further configured to acquire radio frequency signal data generated by an imaging object in a magnetic resonance imaging environment under the excitation of a magnetic resonance scanning sequence after the application of a control gradient pulse, and to generate a magnetic resonance image of the imaging object based on the radio frequency signal data; wherein the magnetic resonance scanning sequence after the application of the control gradient pulse includes a radio frequency pulse, an original gradient pulse, and a control gradient pulse.

[0166] The magnetic resonance imaging system provided in this embodiment can execute the above-described method embodiments, and its implementation principle and technical effect are similar, so they will not be described again here.

[0167] To facilitate understanding by those skilled in the art, the object control method provided in this application is described using a computer device as the execution subject as an example. Specifically, the method includes:

[0168] (1) Obtain the re-converging radio frequency pulses generated corresponding to the magnetic resonance scanning sequence.

[0169] (2) Obtain the current position and target position of the ferromagnetic object in the magnetic resonance imaging environment.

[0170] (3) Determine the relative orientation information of the ferromagnetic object based on its current position and target position in the magnetic resonance imaging environment.

[0171] (4) For any refocusing module in the refocusing RF pulse, obtain the control gradient parameters; the control gradient parameters are determined based on the distance between the current position of the ferromagnetic object and the target position; the control gradient parameters include the size and direction of the gradient block.

[0172] (5) Based on the control gradient parameters, determine the first gradient block and the second gradient block corresponding to the back-convergence module.

[0173] (6) The first gradient block and the second gradient block are determined as the control gradient blocks corresponding to the re-convergence module; wherein the area of ​​the first gradient block is the same as that of the second gradient block, and the first gradient block and the second gradient block are located on both sides of the location of the re-convergence module.

[0174] (7) Determine the control gradient pulse based on the control gradient block corresponding to each re-convergence module.

[0175] (8) Acquire radio frequency signal data generated by the imaging object in the magnetic resonance imaging environment under the excitation of the magnetic resonance scanning sequence after the application of the control gradient pulse; wherein, the magnetic resonance scanning sequence after the application of the control gradient pulse includes the radio frequency pulse, the original gradient pulse and the control gradient pulse.

[0176] (9) Generate a magnetic resonance image of the imaging object based on radio frequency signal data.

[0177] The specific execution process of (1) to (9) above can be found in the description of the above embodiments. The implementation principle and technical effect are similar, and will not be repeated here.

[0178] It should be understood that, although Figure 2 , Figure 6-8 and Figure 14 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 2 , Figure 6-8 and Figure 14 At least some of the steps in the process may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but may be executed at different times. The execution order of these steps or stages is not necessarily sequential, but may be executed in turn or alternately with other steps or at least some of the steps or stages in other steps.

[0179] In one embodiment, such as Figure 16 As shown, an object control device is provided, including: a convergence pulse acquisition module 11, a control pulse determination module 12, and an object motion control module 13, wherein:

[0180] The recoil pulse acquisition module 11 is used to acquire the recoil radio frequency pulses generated corresponding to the magnetic resonance scanning sequence;

[0181] The control pulse determination module 12 is used to determine the control gradient pulse based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment; the direction of the magnetic field force impulse of the control gradient pulse is the same as the direction of the magnetic field force impulse of the original gradient pulse in the magnetic resonance scanning sequence; the control gradient pulse is distributed on both sides of the location of the refocusing radio frequency pulse.

[0182] The object motion control module 13 is used to control the ferromagnetic object to move to the target position by applying the original gradient pulse and control gradient pulse to the magnetic resonance imaging environment.

[0183] The object control device provided in this embodiment can execute the above method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0184] In one embodiment, the refocusing radio frequency pulse includes at least one refocusing module; the control pulse determination module 12 includes: an azimuth information acquisition unit, a control gradient block determination unit, and a first pulse determination unit, wherein:

[0185] The orientation information acquisition unit is used to acquire the relative orientation information of a ferromagnetic object;

[0186] The control gradient block determination unit is used to determine the control gradient block corresponding to each convergence module based on the relative orientation information of the ferromagnetic object and the position of each convergence module.

[0187] The first pulse determination unit is used to determine the control gradient pulse based on the control gradient block corresponding to each convergence module.

[0188] The object control device provided in this embodiment can execute the above method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0189] In one embodiment, the relative orientation information includes the distance between the current position of the ferromagnetic object and the target position; the control gradient block determination unit includes: a gradient block determination subunit and a control gradient block determination subunit, wherein:

[0190] The gradient block determination sub-unit is used to determine the first gradient block and the second gradient block corresponding to any convergence module based on the distance between the current position and the target position of the ferromagnetic object.

[0191] A control gradient block determination subunit is used to determine the first gradient block and the second gradient block as the control gradient blocks corresponding to the re-convergence module; wherein the area of ​​the first gradient block is the same as that of the second gradient block, and the first gradient block and the second gradient block are located on both sides of the location of the re-convergence module.

[0192] The object control device provided in this embodiment can execute the above method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0193] In one embodiment, the gradient block determination subunit is specifically used to acquire control gradient parameters and, based on the control gradient parameters, determine the first gradient block and the second gradient block corresponding to the convergence module; the control gradient parameters are determined according to the interval distance between the current position and the target position of the ferromagnetic object; the control gradient parameters include the size and direction of the gradient block.

[0194] The object control device provided in this embodiment can execute the above method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0195] In one embodiment, the orientation information acquisition unit comprises a position acquisition subunit and an orientation information acquisition subunit, wherein:

[0196] The position acquisition subunit is used to acquire the current position and target position of the ferromagnetic object in the magnetic resonance imaging environment;

[0197] The orientation information acquisition subunit is used to determine the relative orientation information of the ferromagnetic object based on its current position and target position in the magnetic resonance imaging environment.

[0198] The object control device provided in this embodiment can execute the above method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0199] In one embodiment, the convergence module includes an X-direction convergence module, a Y-direction convergence module, and a Z-direction convergence module; the relative orientation information also includes the orientation of the current position of the ferromagnetic object relative to the target position; the control pulse determination module 12 includes a target direction pulse determination unit and a second pulse determination unit, wherein:

[0200] The target direction pulse determination unit is used to determine the target direction control gradient pulse corresponding to the target direction convergence module based on the orientation of the current position of the ferromagnetic object relative to the target position; the target direction convergence module is at least one of the X-direction convergence module, the Y-direction convergence module, and the Z-direction convergence module;

[0201] The second pulse determination unit is used to determine the control gradient pulse based on the position of the target direction control gradient pulse and the recoil radio frequency pulse.

[0202] The object control device provided in this embodiment can execute the above method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0203] In one embodiment, the object control device further includes: a radio frequency data acquisition module and an imaging module, wherein:

[0204] The radio frequency data acquisition module is used to acquire radio frequency signal data generated by the imaging object in the magnetic resonance imaging environment under the excitation of the magnetic resonance scanning sequence after the application of the control gradient pulse; wherein, the magnetic resonance scanning sequence after the application of the control gradient pulse includes the radio frequency pulse, the original gradient pulse, and the control gradient pulse;

[0205] The radio frequency data acquisition module is used to generate magnetic resonance images of the imaging object based on radio frequency signal data.

[0206] The object control device provided in this embodiment can execute the above method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0207] Specific limitations regarding the object control device can be found in the limitations of the magnetic resonance imaging method described above, and will not be repeated here. Each module in the aforementioned object control device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0208] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 17 As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The processor provides computational and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The database stores relative orientation information of internal magnetic resonance images and ferromagnetic objects. The network interface communicates with external endpoints via a network connection. When executed by the processor, the computer program implements a magnetic resonance imaging method.

[0209] Those skilled in the art will understand that Figure 17 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0210] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to perform the following steps:

[0211] Acquire the refocusing radio frequency pulses generated corresponding to the magnetic resonance scanning sequence;

[0212] Based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment, the control gradient pulse is determined; the control gradient pulse is distributed on both sides of the location of the convergent radio frequency pulse.

[0213] By applying raw gradient pulses and control gradient pulses to the magnetic resonance imaging environment, the movement of a ferromagnetic object to the target position can be controlled.

[0214] In one embodiment, a readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, performs the following steps:

[0215] Acquire the refocusing radio frequency pulses generated corresponding to the magnetic resonance scanning sequence;

[0216] Based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment, the control gradient pulse is determined; the control gradient pulse is distributed on both sides of the location of the convergent radio frequency pulse.

[0217] By applying raw gradient pulses and control gradient pulses to the magnetic resonance imaging environment, the movement of a ferromagnetic object to the target position can be controlled.

[0218] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, performs the following steps:

[0219] Acquire the refocusing radio frequency pulses generated corresponding to the magnetic resonance scanning sequence;

[0220] Based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment, the control gradient pulse is determined; the control gradient pulse is distributed on both sides of the location of the convergent radio frequency pulse.

[0221] By applying raw gradient pulses and control gradient pulses to the magnetic resonance imaging environment, the movement of a ferromagnetic object to the target position can be controlled.

[0222] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, storage, databases, 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 storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0223] The technical features of the above embodiments can be combined in any way. For the sake of brevity, 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.

[0224] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An object control method, characterized in that, The method includes: Acquire the refocusing radio frequency pulses generated corresponding to the magnetic resonance scanning sequence; the refocusing radio frequency pulses include at least one refocusing module; Based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment, control gradient pulses are determined; the control gradient pulses are distributed on both sides of the location of each convergence module. By applying the original gradient pulse and the control gradient pulse to the magnetic resonance imaging environment, the ferromagnetic object is controlled to move to the target position; The step of determining the control gradient pulse based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment includes: determining the control gradient block corresponding to each of the convergence modules according to the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment and the position of each convergence module; and determining the control gradient pulse according to the control gradient block corresponding to each of the convergence modules.

2. The object control method according to claim 1, characterized in that, The relative orientation information includes the distance between the current position of the ferromagnetic object and the target position; The step of determining the control gradient block corresponding to each convergence module based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment and the position of each convergence module includes: For any convergence module, the first gradient block and the second gradient block corresponding to the convergence module are determined based on the distance between the current position of the ferromagnetic object and the target position. The first gradient block and the second gradient block are determined as the control gradient blocks corresponding to the convergence module; wherein the area of ​​the first gradient block is the same as that of the second gradient block, and the first gradient block and the second gradient block are located on both sides of the position of the convergence module.

3. The object control method according to claim 2, characterized in that, The step of determining the first gradient block and the second gradient block corresponding to the convergence module based on the interval distance between the current position of the ferromagnetic object and the target position includes: Obtain control gradient parameters; the control gradient parameters are determined based on the distance between the current position of the ferromagnetic object and the target position; the control gradient parameters include the size and direction of the gradient block; Based on the control gradient parameters, the first gradient block and the second gradient block corresponding to the re-convergence module are determined.

4. The object control method according to claim 3, characterized in that, The process of acquiring the relative orientation information of the ferromagnetic object includes: The current position and target position of the ferromagnetic object in the magnetic resonance imaging environment are obtained; The relative orientation information of the ferromagnetic object is determined based on its current position in the magnetic resonance imaging environment and the target position.

5. The object control method according to any one of claims 1-4, characterized in that, The convergence module includes an X-direction convergence module, a Y-direction convergence module, and a Z-direction convergence module; the relative orientation information also includes the orientation of the current position of the ferromagnetic object relative to the target position; The determination of the control gradient pulse based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment includes: Based on the orientation of the current position of the ferromagnetic object relative to the target position, the target direction control gradient pulse corresponding to the target direction convergence module is determined; the target direction convergence module is at least one of the X-direction convergence module, Y-direction convergence module, and Z-direction convergence module; The control gradient pulse is determined based on the position of the target direction control gradient pulse and the refocusing radio frequency pulse.

6. The object control method according to any one of claims 1-4, characterized in that, The method further includes: Acquire radio frequency signal data of the imaging object in the magnetic resonance imaging environment under the excitation of a magnetic resonance scanning sequence after the application of a control gradient pulse; wherein, the magnetic resonance scanning sequence after the application of the control gradient pulse includes a radio frequency pulse, the original gradient pulse, and the control gradient pulse; A magnetic resonance image of the imaging object is generated based on the radio frequency signal data.

7. A magnetic resonance imaging system, characterized in that, The magnetic resonance imaging system includes: a magnetic resonance imaging device and a computer device; the magnetic resonance imaging device includes a magnet and gradient coils; The magnet is used to generate the main magnetic field in the environment where the imaging object is located; The gradient coil is used to generate a gradient magnetic field, which works together with the main magnetic field to provide a magnetic resonance imaging environment. The computer device is used to acquire at least one convergence module corresponding to the magnetic resonance scanning sequence, and to determine the control gradient block corresponding to each convergence module based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment and the position of each convergence module, and to determine the control gradient pulse based on the control gradient block corresponding to each convergence module; the control gradient pulse is distributed on both sides of the position of each convergence module. The magnetic resonance imaging device is used to apply the original gradient pulse and the control gradient pulse to the magnetic resonance imaging environment to control the ferromagnetic object to move to the target position.

8. An object control device, characterized in that, The device includes: A reconvergence pulse acquisition module is used to acquire the reconvergence radio frequency pulses generated corresponding to the magnetic resonance scanning sequence; the reconvergence radio frequency pulses include at least one reconvergence module; The control pulse determination module is used to determine the control gradient block corresponding to each of the reconvergence modules based on the relative orientation information of ferromagnetic objects in the magnetic resonance imaging environment and the position of each reconvergence module, and to determine the control gradient pulse based on the control gradient block corresponding to each of the reconvergence modules; the direction of the magnetic field force impulse of the control gradient pulse is the same as the direction of the magnetic field force impulse of the original gradient pulse in the magnetic resonance scanning sequence; the control gradient pulse is distributed on both sides of the position of each of the reconvergence modules. An object motion control module is used to control the ferromagnetic object to move to a target position by applying an initial gradient pulse and a control gradient pulse to the magnetic resonance imaging environment.

9. The object control device according to claim 8, characterized in that, The relative orientation information includes the distance between the current position of the ferromagnetic object and the target position; The control pulse determination module includes a control gradient block determination unit, which includes: The gradient block determination subunit is used to determine the first gradient block and the second gradient block corresponding to any convergence module based on the distance between the current position of the ferromagnetic object and the target position. A control gradient block determination subunit is used to determine the first gradient block and the second gradient block as the control gradient blocks corresponding to the convergence module; wherein the area of ​​the first gradient block is the same as the area of ​​the second gradient block, and the first gradient block and the second gradient block are located on both sides of the location of the convergence module.

10. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the object control method according to any one of claims 1-6.

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