Pre-scanning control system and method for magnetic resonance imaging system

Abstract

An embodiment of the present invention provides a pre-scanning control system for a magnetic resonance imaging system, wherein a positioning guidance device is coupled to the magnetic resonance imaging system, and the pre-scanning control system comprises: a 3D camera, which is used to capture a three-dimensional image of a scan object located in a first area outside a scanning cavity of the magnetic resonance imaging system, wherein the three-dimensional image at least includes a positioning part and a part of interest of the scan object; a processing device, which is used to determine the positioning information of the scan object relative to the magnetic resonance scanning bed when receiving an imaging scan based on the positional relationship between the positioning part and the part of interest in the three-dimensional image; and a control device, which is used to control the positioning guidance device to send the positioning guidance information based on the positioning information.

Description

Technical Field

[0001] The embodiments disclosed in the present invention relate to medical imaging technology, and more particularly to a pre-scanning control system and method for a magnetic resonance imaging system. Background Art

[0002] Magnetic resonance imaging (MRI) is a medical imaging modality that can obtain three-dimensional images of the human body without using X-rays or other ionizing radiation. When using a magnetic resonance imaging system to image a patient's area of ​​interest, the patient's area of ​​interest needs to be scanned. Before performing a scanning task, a pre-scan task needs to be performed to prepare for the formal scan. For example, it is necessary to input patient information, help the patient position, set scanning parameters, optimize scanning parameters, etc. For different purposes such as improving image quality, simplifying operation procedures, saving operation time, and increasing patient comfort, it is hoped that a more precise and optimized control method can be performed on the magnetic resonance imaging system in each process of pre-scanning and scanning.

[0003] In the prior art, there is still room for optimization in both the pre-scan process and the scanning process to meet the increasingly high clinical diagnosis needs. For example, before scanning, it is necessary to communicate with the patient multiple times or move the patient multiple times to position the patient on the scanning bed in a roughly appropriate position; it is difficult to accurately align the patient's part of interest with the scanning center, which requires a long time for positioning adjustment or affects the image quality; the image quality is reduced due to improper scanning parameter settings or improper coil channel selection, or the image cannot be used for lesion examination and needs to be rescanned. Summary of the invention

[0004] An embodiment of the present invention provides a pre-scanning control system for a magnetic resonance imaging system, wherein a positioning guidance device is coupled to the magnetic resonance imaging system, and the pre-scanning control system comprises:

[0005] a 3D camera, which is used to capture a first three-dimensional image of a scanned object in a first area outside a scanning cavity of the magnetic resonance imaging system, wherein the first three-dimensional image includes at least a positioning part and a part of interest of the scanned object;

[0006] a processing device, which is used to determine first positioning information of the scanned object relative to the magnetic resonance scanning bed when the scanned object is subjected to imaging scanning based on the positional relationship between the positioning part and the part of interest in the first three-dimensional image; and

[0007] The control device is used to control the positioning guidance device to issue positioning guidance information based on the first positioning information.

[0008] Optionally, the processing device is used to calculate the distance between the positioning part and the part of interest in the first three-dimensional image, and calculate the first positioning information based on the distance between the positioning part and the part of interest and predetermined second positioning information of the part of interest relative to the magnetic resonance scanning bed.

[0009] Optionally, the second positioning information is determined based on a position of a receiving coil matched with the site of interest relative to the magnetic resonance scanning bed, and the receiving coil is arranged in the magnetic resonance scanning bed.

[0010] Optionally, the first area is opposite to a patient entrance of the scanning cavity and has a space between the first area and a scanning bed of the magnetic resonance imaging system.

[0011] Optionally, the positioning part is the buttocks of the scanned object.

[0012] Optionally, the first three-dimensional image includes at least two reference parts of the scanned object, the processing device is used to determine the height of the scanning bed of the magnetic resonance imaging system based on the positional relationship between the two reference parts in the first three-dimensional image, and the control device is used to control the scanning bed to rise or fall to the height.

[0013] Optionally, the processing device determines the height of the scanning bed based on a distance between two reference locations in the first three-dimensional image.

[0014] Optionally, the two reference parts are respectively the knee and the foot of the scanned object.

[0015] Another embodiment of the present invention further provides a pre-scanning control method for a magnetic resonance imaging system, wherein a positioning guidance device is coupled to the magnetic resonance imaging system, and the pre-scanning control method comprises:

[0016] Acquire a first three-dimensional image of a scanned object in a first area outside a scanning cavity of the magnetic resonance imaging system captured by a 3D camera, wherein the first three-dimensional image includes at least a positioning site and a site of interest of the scanned object;

[0017] Determining first positioning information of the scanned object relative to the magnetic resonance scanning bed when the scanned object is receiving imaging scanning based on the positional relationship between the positioning part and the part of interest in the first three-dimensional image; and

[0018] The positioning guidance device is controlled to issue positioning guidance information based on the first positioning information.

[0019] Optionally, determining first positioning information of the scanned object relative to the magnetic resonance scanning bed when receiving the imaging scan based on the positional relationship between the positioning part of the first three-dimensional image and the part of interest includes:

[0020] The distance between the positioning site and the site of interest in the first three-dimensional image is calculated, and the first positioning information is calculated based on the distance between the positioning site and the site of interest and predetermined second positioning information of the site of interest relative to the magnetic resonance scanning bed.

[0021] Optionally, the second positioning information is determined based on a position of a receiving coil matched with the site of interest relative to the magnetic resonance scanning bed, and the receiving coil is arranged on the magnetic resonance scanning bed.

[0022] Optionally, the first area is opposite to a patient entrance of the scanning cavity and has a space between the first area and a scanning bed of the magnetic resonance imaging system.

[0023] Optionally, the positioning part is the buttocks of the scanned object.

[0024] Optionally, the first three-dimensional image includes at least two reference parts of the scanned object, and the method further includes:

[0025] determining the height of the scanning bed of the magnetic resonance imaging system based on the positional relationship between the two reference parts in the first three-dimensional image; and,

[0026] The scanning bed is controlled to rise or fall to the height.

[0027] Optionally, the height of the scanning bed is determined based on a distance between two reference locations in the first three-dimensional image.

[0028] Optionally, the two reference parts are respectively the knee and the foot of the scanned object.

[0029] Another embodiment of the present invention further provides a pre-scanning control system for a magnetic resonance imaging system, comprising:

[0030] A storage device storing a standard human body image having a plurality of human anatomical structures;

[0031] a 3D camera, the 3D camera being used to capture a second three-dimensional image of a scan object located on a scanning bed of the magnetic resonance imaging system;

[0032] a processing device for identifying a plurality of feature points in the second three-dimensional image, and adjusting the standard human body image based on distribution information of the identified feature points to obtain a matching image adapted to the body features of the scanned object; the processing device is also used to identify a region of interest selected in the matching image; and,

[0033] A control device is used to control the movement of the scanning bed to position the part of interest of the scan object corresponding to the selected region of interest to a preset position.

[0034] Optionally, the processing device is further used to calculate the position information of the head of the scanned object in the moving direction of the scanning bed based on the second three-dimensional image, and to estimate the moving speed of the scanning bed at different positions based on a predetermined curve of the moving speed of the scanning bed changing with its position in the moving direction; and the control device is used to control the scanning bed to move at a changing speed based on the estimated moving speed.

[0035] Optionally, the position information of the head of the scan object in the moving direction of the scanning bed includes the distance between the head of the scan object and a scanning center of the magnetic resonance imaging system.

[0036] Optionally, the 3D camera is further used to capture a third three-dimensional image of a scan object located on a scanning bed of the magnetic resonance imaging system and a surface receiving coil coupled to the scan object; the processing device is used to identify the surface receiving coil and a part of interest of the scan object in the third three-dimensional image, and calculate whether the position of the surface receiving coil matches the position of the part of interest; when the position of the surface receiving coil does not match the position of the part of interest, the control device is used to control the magnetic resonance imaging system to issue a warning message.

[0037] Another embodiment of the present invention further provides a pre-scanning control method for a magnetic resonance imaging system, comprising:

[0038] acquiring a second three-dimensional image of a scan object located on a scanning bed of the magnetic resonance imaging system, taken by a 3D camera;

[0039] identifying a plurality of feature points in the second three-dimensional image;

[0040] adjusting a pre-stored standard human image into a matching image adapted to the body features of the scanned object based on distribution information of the identified feature points, wherein the standard human image has a plurality of human anatomical structures;

[0041] identifying a selected region of interest in the matching image; and,

[0042] The scanning bed is controlled to move so as to position the part of interest of the scanned object corresponding to the selected region of interest to a preset position.

[0043] Optionally, controlling the movement of the scanning bed further includes: calculating position information of the head of the scanned object in the moving direction of the scanning bed based on the second three-dimensional image; estimating the moving speed of the scanning bed at different positions based on a predetermined curve of the moving speed of the scanning bed changing with its position in the moving direction; and controlling the scanning bed to move at a varying speed based on the estimated moving speed.

[0044] Optionally, the position information of the head of the scan object in the moving direction of the scanning bed includes the distance between the scan object and a scanning center of the magnetic resonance imaging system.

[0045] Optionally, the method further includes: acquiring a third three-dimensional image of a scan object located on a scanning bed of the magnetic resonance imaging system and a surface receiving coil coupled to the scan object, taken by the 3D camera; and identifying the surface receiving coil and a part of interest of the scan object in the third three-dimensional image, and calculating whether the position of the surface receiving coil matches the position of the part of interest, wherein when the position of the surface receiving coil does not match the position of the part of interest, controlling the magnetic resonance imaging system to issue a warning message.

[0046] It should be understood that the brief description above is provided to introduce some concepts further described in the detailed description in a simplified form. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is solely defined by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages mentioned above or in any section of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The present invention will be better understood by reading the following description of non-limiting embodiments with reference to the accompanying drawings, in which:

[0048] Figure 1 A block diagram of an example of a magnetic resonance imaging system is shown.

[0049] Figure 2 A schematic structural diagram of a pre-scan control system according to an embodiment of the present invention is shown.

[0050] Figure 3 A schematic structural diagram of a pre-scan control system according to another embodiment of the present invention is shown.

[0051] Figure 4 A schematic structural diagram of a pre-scan control system according to another embodiment of the present invention is shown.

[0052] Figure 5 An example diagram of the spatial field gradient that varies with position in the moving direction of the moving bed.

[0053] Figure 6 This is an example diagram of the movement speed of the moving bed board changing with its position in the moving direction.

[0054] Figure 7 A schematic structural diagram of a pre-scan control system according to another embodiment of the present invention is shown.

[0055] Figure 8 , Fig. 9 , Fig.10 , Fig.12 Flowcharts of an embodiment of a pre-scan control method are respectively shown.

[0056] Fig.11 Shows Fig.10 A flow chart of an embodiment of controlling the movement of a scanning bed.

[0057] Fig.13 A schematic structural diagram of a scanning control system according to an embodiment of the present invention is shown.

[0058] Fig.14 Example diagrams showing a scanned object in various body positions are shown.

[0059] Fig.15 FIG. 4 is a schematic diagram showing the structure of a scanning control system according to another embodiment of the present invention.

[0060] Fig.16 A schematic structural diagram of a scanning control system according to another embodiment of the present invention is shown.

[0061] Fig.17 and Fig.18 The flowcharts of a scanning control method for a magnetic resonance imaging system according to an embodiment of the present invention are respectively shown. DETAILED DESCRIPTION

[0062] Various embodiments described below include a pre-scan control system and method for a magnetic resonance imaging system, Figure 1 A block diagram of an example of a magnetic resonance imaging system is shown.

[0063] like Figure 1 As shown, the magnetic resonance imaging (MRI) system 100 includes a scanner 110 , a table 120 , a controller unit 130 , a data processing unit 140 , an operation console 150 and a display unit 160 .

[0064] In one example, the scanner 110 may include a main magnet assembly 111, which generally includes an annular superconducting magnet defined in a housing, and the annular superconducting magnet is installed in an annular vacuum container. The annular superconducting magnet and its housing define a cylindrical space surrounding the scanned object 16, that is, Figure 1 The scanning bore 116 is shown. The scanning bore 116 defines an imaging region or at least a portion of an imaging region of the magnetic resonance imaging system.

[0065] The main magnet assembly 111 is arranged in the scanning room, and a first area 101, a second area 102 and a third area 103 may be defined outside the main magnet assembly 111, wherein the first area 101 is located outside the scanning cavity 116, and specifically, the first area 101 may be any area in the scanning room where the scanned object can stay before being positioned on the bed 120. The second area 102 may be an area defining the bed 120, and the third area 103 may be an area located outside the scanning cavity and opposite to the rear end of the scanning cavity, wherein the rear end of the scanning cavity refers to the end opposite to the patient entrance of the scanning cavity, for example, the third area 103 may include a positioning area of ​​the rear bridge of the main magnet assembly 111.

[0066] The bed 120 is used to carry the scanned object 16, such as a patient. The bed 120 may include a lifting platform (not shown in the figure) and a movable bed plate arranged on the lifting platform. The bed 120 is generally fixed at the front end of the main magnet assembly 111. The movable bed plate is used to carry the scanned object 16, and is configured to be connected to the patient entrance of the scanning cavity 116, and to move along the above-mentioned Z direction so that the scanned object 16 on it enters and exits the scanning cavity 116, or moves along the Z direction in the scanning cavity. That is, the movable bed plate can be moved from outside the imaging area to an imaging position in the imaging area, and the imaging position can be different based on the part to be imaged. The movable bed plate can also be stepped between multiple imaging positions in the imaging area to perform imaging of multiple imaging parts such as whole-body imaging.

[0067] The scanner 110 further includes an RF transmitting coil 112, a radio frequency generator 113, a gradient coil assembly 114, a gradient coil driver 115, an RF receiving coil 170, and a data acquisition unit 117. When performing an imaging scanning process on a part of interest of the scanned object 16, the scanner 110 is used to obtain image data of the scanned object 16.

[0068] Specifically, the main magnet assembly 111 generates a constant magnetic field, such as a static magnetic field B0, along the Z direction of the scanning cavity 116. The MRI system 100 uses the static magnetic field B0 to transmit a static magnetic pulse signal to the object 16 placed in the scanning cavity 116, so that the precession of protons in the object 16 is ordered and a longitudinal magnetization vector is generated.

[0069] The RF generator 113 is used to generate RF pulses, such as RF excitation pulses. The RF excitation pulses are amplified (for example, by an RF power amplifier (not shown)) and then applied to the RF transmitting coil 112, so that the RF transmitting coil 112 transmits an RF magnetic field B1 orthogonal to the static magnetic field B0 to the scanned object 16 to excite the atomic nuclei in the object 16, and the longitudinal magnetization vector is converted into a transverse magnetization vector.

[0070] In one embodiment, the RF transmitting coil 112 may be a body coil, which may be connected to a transmit / receive (T / R) switch (not shown). The body coil may be switched between a transmit mode and a receive mode by controlling the transmit / receive switch. In the receive mode, the body coil may be used to receive magnetic resonance signals from the subject 16. The RF transmitting coil 112 may also be a local coil dedicated to a certain body part of the patient, such as a head coil.

[0071] When the radio frequency excitation pulse ends, a free induction decay signal is generated in the process that the transverse magnetization vector of the object 16 gradually returns to zero, that is, a magnetic resonance signal that can be collected.

[0072] The gradient coil assembly 114 forms a gradient magnetic field in the imaging space to provide three-dimensional position information for the magnetic resonance signal. The magnetic resonance signal can be received by the RF receiving coil 170 or the body coil in the receiving mode.

[0073] The gradient coil assembly 114 may include three gradient coils, each of which generates a gradient magnetic field tilted to one of three spatial axes (e.g., X-axis, Y-axis, and Z-axis) perpendicular to each other, and generates a gradient field in each of a slice selection direction, a phase encoding direction, and a frequency encoding direction according to imaging conditions. More specifically, the gradient coil assembly 114 applies a gradient field in the slice selection direction of the object 16 so as to select a slice; and the RF transmitting coil 112 transmits an RF excitation pulse to the selected slice of the scanned object 16 and excites the slice. The gradient coil assembly 114 also applies a gradient field in the phase encoding direction of the scanned object 16 so as to phase encode the magnetic resonance signal of the excited slice. The gradient coil assembly 114 then applies a gradient field in the frequency encoding direction of the object 16 so as to frequency encode the magnetic resonance signal of the excited slice.

[0074] The gradient coil driver 115 is used to respond to the sequence control signal sent by the controller unit 130 to provide appropriate power signals for the three gradient coils respectively.

[0075] The RF receiving coil 170 is used to receive the magnetic resonance signals with the three-dimensional position information. Depending on the imaging site, the RF receiving coil 170 may include a surface coil array unit attached to the surface of the scan object 16, or may include a surface coil array unit disposed on the side of the bed 120 facing away from the scan object 16. The RF receiving coil 170 should be positioned sufficiently close to the site of interest of the scan object 16 to receive high-quality magnetic resonance signals.

[0076] The data acquisition unit 117 is used to acquire the magnetic resonance signal received by the RF receiving coil 170. The data acquisition unit 117 may include, for example, a radio frequency preamplifier, a phase detector, and an analog / digital converter, wherein the radio frequency preamplifier is used to amplify the magnetic resonance signal received by the RF receiving coil 170 or the body coil, the phase detector is used to perform phase detection on the amplified magnetic resonance signal, and the analog / digital converter is used to convert the phase-detected magnetic resonance signal from an analog signal to a digital signal.

[0077] The digitized magnetic resonance signals can be processed by the data processing unit 140 for calculation, reconstruction and other processing to obtain the required image or image data. The data processing unit 140 may include a computer and a storage medium on which a program for predetermined data processing to be executed by the computer is recorded. The data processing unit 140 may be connected to the data acquisition unit 117 to receive the magnetic resonance signals output by the data acquisition unit 117 so as to perform the above-mentioned calculation, reconstruction and other processing. In one embodiment, the data processing unit 140 may include an image reconstruction unit 141 for reconstructing an image of the anatomical structure of the scanned object 16 based on the above-mentioned image data.

[0078] The controller unit 130 is coupled to the scanner 110, the bed 120, the data processing unit 140 and the operation console 150, so as to control the corresponding components to perform the required operations in the pre-scanning process or the scanning process of the magnetic resonance imaging. For example, the controller unit 130 is used to receive and process the operation signal input to the operation console 150, and control the working state of the above-mentioned components such as the scanner 110 and the bed 120 based on the operation signal. The operation signal may include, for example, the scanning protocol and parameters selected manually or automatically, the start and stop, lifting and moving speed of the bed 120, and the communication information with the scanned object such as positioning guidance and warning. The controller unit 130 also controls the data processing unit 140 based on the operation signal received from the operation console 150 to obtain the desired image.

[0079] The controller unit 130 may include a computer and a storage medium, wherein the storage medium is used to store a program that can be executed by the computer. When the computer executes the program, the scanner 110, the bed 120, the display unit 160 and other components may perform corresponding operations in the pre-scanning process, the scanning process or the equipment maintenance process. The data processing unit 140 may also be enabled to perform predetermined data processing.

[0080] In this embodiment, the controller unit 130 can control the start and stop of the moving bed plate, the moving speed, etc. based on the user's operation instructions or some detection signals, so as to position the part of interest of the scanned object 16 to align with the scanning center of the magnetic resonance imaging system (for example, the center of the main magnet assembly), so as to facilitate imaging scanning of the part of interest. The controller unit 130 can also be configured to control other components of the scanner 110, the data processing unit 140, and the display unit 160.

[0081] Before positioning the part of interest of the scanned object 16 , auxiliary equipment may be used to help the scanned object quickly position itself at a suitable part of the bed 120 , thereby avoiding excessive position adjustments of the scanned object in order to position the part of interest.

[0082] The auxiliary device may be a positioning guide device 180 coupled to the magnetic resonance imaging system, such as a projection device or infrared device that can project a positioning mark on the bed 120, and the positioning mark is used to guide the scanning object to be positioned relative to the bed 120 in the pre-scanning process. The positioning guide device 180 may be installed on the housing of the main magnet assembly 111, or fixed above the bed 120 in other installation methods.

[0083] The storage medium of the controller unit 130 and the data processing unit 140 may include, for example, a ROM, a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, or a nonvolatile memory card.

[0084] The operation console 150 may include a user input device, such as a keyboard and a mouse, through which an operator may input an operation signal / control signal to the controller unit 130 .

[0085] The display unit 160 may be connected to the operation console 150 to display an operation interface, and may also be connected to the data processing unit 140 to display a reconstructed image or various images captured by a camera coupled to the magnetic resonance imaging system.

[0086] The above MRI system 100 is described only as an example. In other embodiments, the MRI system 1 may have a variety of transformation forms as long as it can acquire image data from the imaging object.

[0087] First embodiment

[0088] Figure 2 FIG. 1 shows a schematic diagram of a pre-scan control system according to an embodiment of the present invention. The pre-scan control system is used in a magnetic resonance imaging system. For example, the pre-scan control system can be used with Figure 1 The pre-scan control system may include a 3D camera 210 , a processing device 220 and a control device 230 .

[0089] The 3D camera is used to obtain a three-dimensional image of the scan object 16 located in the first area 101. Figure 2 As shown, the 3D camera can be set at a higher position in the scanning room, for example, directly above or diagonally above the bed 120, and the 3D camera can be fixed by using the ceiling of the scanning room or the equipment at a higher position of the magnetic resonance imaging system.

[0090] As an example, when the scan object 16 first enters the scanning room, the scan object 16 may be guided to pass through the first area 101 or stay therein for a short time, so that the 3D camera can take a picture of the scan object 16 .

[0091] In one example, the first area 101 is opposite to the patient entrance of the scanning cavity 116 relative to the bed 120 , that is, the bed 120 is located between the first area 101 and the scanning cavity 116 , and there is space between the first area 101 and the bed 120 to avoid interference when photographing the scanned object 16 .

[0092] The captured first three-dimensional image includes at least a positioning part 161 and an interesting part 162 of the scanned object 16. The positioning part 161 is a characteristic part of the human body that is easy to identify in the image, such as the buttocks.

[0093] The processing device 220 is configured (programmed) to determine first positioning information of the scanned object 16 based on the positional relationship between the positioning part 161 and the part of interest 162 of the three-dimensional image. The first positioning information is the positioning information of the scanned object relative to the bed 120 when the scanned object is subjected to the imaging scan. For example, it can be used to indicate at which position of the bed 120 the positioning part 161 of the scanned object should be located so that the part of interest 162 can be exactly opposite to the receiving coil coupled in 120.

[0094] The part of interest 162 may be a part to be imaged for diagnosis. The processing device 220 may determine the part of interest to be imaged according to the scanning protocol selected by the user via the operation console 150 and identify the part of interest in the three-dimensional image.

[0095] In one embodiment, the processing device 220 is used to calculate the distance D1 between the positioning part 161 and the part of interest 162 in the three-dimensional image, and calculate the first positioning information based on the distance D1 and the pre-identified second positioning information of the part of interest 162 relative to the bed 120.

[0096] The second positioning information is predetermined based on the position of the receiving coil matching the part of interest relative to the bed 120. In one embodiment, the receiving coil is disposed in the movable bed board of the bed 120. The second positioning information may be the position information of the receiving coil coupled in the bed 120 relative to the bed 120.

[0097] For example, assuming that the position where the receiving coil is coupled to the bed 120 is marked as I1, then the position at a distance D1 from the point I1 is the positioning point of the positioning part 161 of the scan object on the bed 120.

[0098] The control device 230 is used to control the positioning guidance device 180 to issue positioning guidance information based on the first positioning information, as described above in conjunction with Figure 1 As described, the positioning guidance device 180 can send positioning guidance information by projecting a guidance mark. For example, a guidance mark M1 is projected at the above-mentioned positioning point of the bed 120 to indicate that the positioning part (such as the buttocks) of the scanned object 16 is located at the guidance mark. In this way, the scanned object can first sit at the guidance mark, and then when lying flat, the part of interest such as the chest or other parts can be located at the appropriate position (for example, I1).

[0099] Optionally, the three-dimensional image captured by the 3D camera 210 further includes at least two reference parts 163, 164 of the scanned object 16, and the lifting height of the bed 120 can be controlled based on the information of the reference parts 163, 164, so that the scanned object 16 can more easily position its positioning part 161 at the above-mentioned appropriate position of the bed 120. Specifically, the processing device 220 is used to determine the height of the bed 120 based on the positional relationship between the two reference parts 163, 164 in the first three-dimensional image, and the control device 230 is used to control the bed 120 to be raised or lowered to the above-mentioned height.

[0100] For example, the two reference parts 163 and 164 are the knee (e.g., knee, knee pit) and foot (e.g., sole, toe, heel) of the scanned object, respectively, and the processing device 220 determines the height of the bed 120 based on the distance D2 between the two reference parts 163 and 164. For example, the processing device 220 calculates that the height suitable for the current scanned object 16 is D2, and the current height of the bed 120 is H1, and the processing device 220 outputs H1-D2. When H1-D2 is greater than 0, the control device 230 controls the bed 120 to descend by H-D2, otherwise, the control device 230 controls the bed 120 to rise by D2-H.

[0101] The processing device 220 and the control device 40 may include a computer and a storage medium, wherein the storage medium is used to store a program that can be executed by the computer. When the computer executes the program, the above-mentioned positioning guidance of the scanned object can be achieved.

[0102] The processing device 220 and the control device 230 are preferably integrated with the computer and the storage medium of the magnetic resonance imaging system, or they may be configured independently.

[0103] Second embodiment

[0104] The above embodiments describe positioning the part of interest of the scanned object to a position corresponding to the receiving coil disposed in the bed 120. It should be understood that when performing magnetic resonance imaging, magnetic resonance signals can also be received with the aid of a surface coil that can be covered on the human body. It is usually desirable to place the surface coil sufficiently close to the part of interest (for example, the center of the part of interest is opposite to the center of the surface coil) so that the quality of the received magnetic resonance signals is good enough.

[0105] Figure 3 FIG. 4 is a schematic diagram showing the structure of a pre-scanning control system according to another embodiment of the present invention. As an example, the pre-scanning control system can be applied to Figure 1 The magnetic resonance imaging system shown in FIG. The pre-scan control system provided in this embodiment can provide guidance / prompts / warnings to the user to position the surface coil more quickly. Figure 3 As shown, the pre-scan control system includes a 3D camera 310 , a processing device 320 and a control device 330 .

[0106] The 3D camera 310 can be the same device as the 3D camera 210 or a device installed and set in a similar manner. The 3D camera 310 is used to capture a three-dimensional image of the scanned object 16 located in the second area 102 and the surface receiving coil 171 coupled to the scanned object. For example, when the scanned object 16 lies flat or is positioned on the bed 120 in other postures that are conducive to scanning, and when the surface receiving coil 171 is in place (for example, covering a part of interest of the human body), the 3D camera 310 can be used to obtain a three-dimensional image of the scanned object 16 and the surface receiving coil 171 thereon.

[0107] The processing device 320 is configured (programmed) to determine whether the positions of the surface receiving coil 171 and the region of interest of the scanned object match based on the positional relationship between the surface receiving coil 171 and the scanned object 16 in the three-dimensional image.

[0108] As an example, the processing device 320 may first identify the surface receiving coil 171 and the scanned object 16 in the three-dimensional image based on the pre-set characteristic information of the surface receiving coil 171 and the scanned object 16, respectively. The characteristic information may include one or more of information such as size, contour, depth, etc. The processing device 320 may determine the position of the part of interest in the identified scanned object based on the distribution information of the pre-determined human anatomical structure, or may estimate the position of the part of interest through, for example, depth information reflected in the three-dimensional image, and the position may be a position range with a position center. The processing device 320 may further determine the position center of the identified surface receiving coil, and determine whether the position center of the surface receiving coil corresponds to the position center of the part of interest.

[0109] The control device 330 is configured (programmed) to control the magnetic resonance imaging system to issue a warning when the position between the surface receiving coil 171 and the part of interest of the scanned object does not match. For example, the control device 330 can be coupled with the display unit 160 to control the display unit 160 to display mismatch information, and the mismatch information can further show the relative position relationship between the two position centers, such as the offset and the offset direction, so as to remind the user how to adjust the relative position between the surface receiving coil and the part of interest of the scanned object 16. The control device 330 can also be coupled with the voice device of the magnetic resonance imaging system to prompt the user with the above mismatch information.

[0110] Of course, the region of interest of the scanned object and the surface receiving coils (eg, Figure 3 For example, the processing device 320 may first identify the bed 120 and the scanned object 16 in the image, and determine the position of the part of interest in the identified scanned object. Since the position of the surface receiving coil 172 is fixed, that is, the surface receiving coil has a predetermined positional relationship relative to the bed 120, the processing device 320 may further determine whether the position of the part of interest matches the position of the surface receiving coil. If they do not match, a mismatch information may also be issued for the surface receiving coil 172.

[0111] In one embodiment, when the same 3D camera is used to respectively photograph the first area and the second area, the control device 330 is further configured to control the shooting angle of the 3D camera so as to be able to switch between a first shooting angle adapted to the first area 101 and a second shooting angle adapted to the second area 102.

[0112] Third embodiment

[0113] Figure 4FIG. 4 is a schematic diagram showing the structure of a pre-scanning control system according to another embodiment of the present invention. As an example, the pre-scanning control system can be applied to Figure 1 The magnetic resonance imaging system shown in FIG. Figure 4 As shown, the pre-scan control system includes a 3D camera 410 , a processing device 420 , a control device 430 and a storage device 440 .

[0114] The storage device 440 is used to store standard human body images, such as Figure 4 The image G1 (Golden Image) shown in the figure shows multiple human anatomical structures, such as various organs, bones, etc. Multiple different standard human images can be stored based on age, gender or other classification criteria, so that an image matching the current scan object can be called during the pre-scan process.

[0115] The 3D camera 410 can be the same device as the 3D camera 310 or a device installed and set in a similar manner. The 3D camera 410 is used to photograph the scan object 16 located on the bed 120. For example, when the scan object 16 lies flat or is positioned on the bed 120 in other postures that are conducive to scanning, the 3D image C1 (Camera Image) of the scan object 16 can be obtained through the 3D camera 410.

[0116] The processing device 420 is used to identify multiple feature points 401 in the above-mentioned three-dimensional image C1, and determine the matching image P1 (Patient Image) of the standard human image based on the distribution information of the identified feature points 401, wherein the feature points of the three-dimensional image C1 can reflect the body feature information of the scanned object 16, such as one or more of body proportions, body contours, body height, and body thickness. Through processing such as scaling, local scaling, and proportional adjustment, the parts corresponding to the multiple feature points in the standard human image G1 (Golden Image) can be adjusted to a similar distribution, so that the multiple human anatomical structures in the standard human image G1 are adapted to the body features of the scanned object. In one example, the feature points 401 may include multiple main joints of the human body.

[0117] The matching image P1 can be presented to the user through the display unit 160 of the magnetic resonance imaging system, and the region of interest can be determined based on the operation on the matching image P1. For example, the operator can select the anatomical structure of interest (hereinafter referred to as the matching anatomical structure) in the matching image through auxiliary tools such as points, lines or boxes. For example, the operator can select the matching anatomical structure 402 as the region of interest in the image P1.

[0118] In other embodiments, the selection of the region of interest may be achieved through other more intelligent methods, such as image recognition, machine learning, and the like.

[0119] The processing device 420 is also used to identify the region of interest selected in the matching image P1, which can be mapped to a body part of the scanned object 16. Generally, before executing the scanning procedure, the center of the region of interest of the scanned object 16 needs to be aligned with the scanning center, which needs to be accomplished by moving the operating bed 120.

[0120] The control device 430 is coupled to the bed 120 of the magnetic resonance imaging system. Based on the region of interest identified by the processing device 420, the control device 430 is used to control the movement of the bed 120 to position the body part of the scanned object 16 corresponding to the region of interest to a preset position.

[0121] The preset position may be an imaging position determined in the imaging area, such as a position in the scanning cavity 116 that is opposite to the scanning center.

[0122] Fourth embodiment

[0123] Such as Figure 1 In the magnetic resonance imaging system shown, the main magnetic field provided by the main magnet assembly 111 is not uniform, but varies in the entire imaging area, and the imaging area can be understood as having a spatial field gradient (for example, a variation in field intensity along the Z direction), which may be different within different position ranges in the imaging area.

[0124] Figure 5 : is an example diagram of the spatial field gradient that varies with position in the moving direction (ie, Z direction) of the moving bed. Figure 5 The horizontal axis in represents the linear position along the Z direction, and the vertical axis represents the spatial field gradient, wherein the linear position of the horizontal axis is labeled with positive and negative displacement values ​​relative to the scan center 550. In one embodiment, the unit of the spatial field gradient is Tesla / meter (T / m). Figure 5 It can be seen that the field experienced by the human body at different positions in the Z direction is changing.

[0125] Additionally, the magnitude of the spatial field gradient varies with patient size, as an example, Figure 5 Three spatial field gradient curves 510, 520 and 530 are shown for large, medium and small sized patients respectively.

[0126] like Figure 5 As shown, each of the curves 510, 520, and 530 has a substantially similar shape. For example, at the entry portion 501 from -300 cm to -200 cm, the gradient is zero or close to zero. The entry portion 501 corresponds to a position range in which the human brain is completely or almost completely outside the cavity 112 and the imaging area defined by it.

[0127] Next, the first portion 502 of each gradient curve starting at about -200 centimeters corresponds to the portion where the brain enters the imaging region and approaches the scan center 550. At about -80 centimeters in the example shown, the gradient reaches a peak 503, and then the gradient decreases as the curve gets closer to the scan center 550.

[0128] The second portion 504 of each gradient curve is located on the other side of the scan center 550 and at a position within about 20 centimeters from the scan center 550, and corresponds to a position where the brain of the human body is located at or near the scan center 550. For the second portion 504, the gradient is zero or a relatively low value.

[0129] The third portion 505 of each curve is encountered as the brain of the person progresses further away from the scan center 550. The gradient reaches a peak 506 at about 80 centimeters in the example shown, and then decreases as the brain approaches the farther edge of the field within the imaging region.

[0130] It is generally believed that the human brain is more affected by field changes than other parts of the body, and patient comfort is usually related to field changes over time rather than changes over distance. Therefore, it is necessary to control the speed of the brain when passing through different spatial gradient fields to avoid causing discomfort or safety accidents.

[0131] Accordingly, Figure 6 This is an example diagram of the movement speed of the moving bed board changing with its position in the movement direction (Z direction). Figure 6 The horizontal axis in represents the linear position along the Z direction, specifically represented by positive and negative displacement values ​​relative to the scan center 550. Figure 6 The vertical axis in represents the maximum speed limit of the moving bed at the corresponding position, that is, the safe speed. Figure 6 Three moving speed curves 610, 620 and 630 for large, medium and small patients are shown in FIG. Figure 6 It can be seen that because the spatial field gradient is higher for larger patients, the velocity curve 610 includes lower velocities than the other curves. In general, the velocity represented by each curve is lower when the gradient is high and higher when the gradient is low. Each curve 610, 620, 630 includes: a first position 602, which corresponds to Figure 5 a first portion 502 of the curve; a second portion 604 , which corresponds to the second portion 504 ; and a third portion 605 , which corresponds to the third portion 505 .

[0132] Figure 7FIG. 1 shows a schematic diagram of a pre-scan control system according to another embodiment of the present invention. The pre-scan control system is used in a magnetic resonance imaging system. For example, the pre-scan control system can be used with Figure 1 The magnetic resonance imaging system shown is coupled. Figure 7 As shown, the pre-scan control system includes a 3D camera 710 , a processing device 720 and a control device 730 .

[0133] The 3D camera 710 can be the same device as the 3D cameras 210, 310, and 410, or a device installed and set in a similar manner. The 3D camera 710 is used to photograph the scan object 16 located on the bed 120. For example, when the scan object 16 lies flat or is positioned on the bed 120 in other postures that are conducive to scanning, a three-dimensional image of the scan object 16 can be obtained through the 3D camera 710.

[0134] The processing device 720 is configured (programmed) to obtain a curve of the movement speed of the bed 120 versus the position in the Z direction, which curve may be, for example, Figure 6 The processing device 710 may, for example, pre-acquire the following Figure 5 The spatial field gradient curve is shown in FIG. , and then based on the spatial field gradient curve, the following is obtained: Figure 6 The speed curve of the bed 120 shown, and the speed curves corresponding to different body types can be pre-stored in a storage device coupled to the processing device 720, and the processing device 720 retrieves the corresponding speed curve based on the pre-input body type of the scanned object.

[0135] On the other hand, the processing device 720 is configured to identify the head of the scanned object 16 in the three-dimensional image taken by the above-mentioned 3D camera, calculate the current position of the head of the scanned object 16 based on the recognition result, and predict the moving speed of the scanned object 16 based on the current position of the head of the scanned object.

[0136] The control device 730 is configured to be coupled to the drive of the bed 120 and to control the bed 120 based on the predicted moving speed of the scan object 16. For example, the scan object may be moved faster through the portion where the spatial field gradient is relatively low (e.g., the entry portion 501 and the second portion 504), and may be moved slower through the portion where the spatial field gradient is relatively high (e.g., the first portion 502 and the third portion 505).

[0137] When the scan is finished, the moving speed of the bed 120 can be controlled in a similar manner according to the spatial field gradient to move the scanned object 16 out of the scanning cavity.

[0138] Based on the above embodiments, the present invention can also provide a pre-scanning control method for a magnetic resonance imaging system, wherein Figure 8 , Fig. 9 , Fig.10 , Fig.12 Flowcharts of an embodiment of a pre-scan control method are respectively shown. Fig.11 Shows Fig.10 A flow chart of an embodiment of controlling the movement of a scanning bed.

[0139] like Figure 8 As shown, in one embodiment, the pre-scanning control method includes steps S810 to S830.

[0140] In step S810, a first three-dimensional image of a scan object in a first area outside a scan cavity of a magnetic resonance imaging system is acquired by a 3D camera, wherein the first three-dimensional image includes at least a positioning part (e.g., buttocks) and a part of interest (e.g., chest) of the scan object.

[0141] In step S820, first positioning information of the scanned object relative to the magnetic resonance scanning bed (eg, bed 120) when receiving the imaging scan is determined based on the positional relationship between the positioning part of the first three-dimensional image and the part of interest.

[0142] In step S830, a positioning guidance device (eg, Figure 1 The device 180 shown) sends positioning guidance information.

[0143] Step S820 may further include: calculating the distance between the positioning part and the part of interest in the first three-dimensional image, and calculating the first positioning information based on the distance between the positioning part and the part of interest and predetermined second positioning information of the part of interest relative to the magnetic resonance scanning bed.

[0144] Further, the second positioning information is determined based on the position of a receiving coil (eg, receiving coil 171 ) matched with the site of interest relative to the magnetic resonance scanning bed, and the receiving coil is arranged on the magnetic resonance scanning bed.

[0145] The first three-dimensional image includes at least two reference parts of the scanned object, such as the knee and the foot. Fig. 9 The method shown includes steps S910 and S920.

[0146] In step S910, the height of a scanning bed of the magnetic resonance imaging system is determined based on the positional relationship between the two reference parts in the first three-dimensional image. In step S920, the scanning bed is controlled to rise or fall to the height.

[0147] In step S910, the height of the scanning bed may be determined based on the distance between two reference parts in the first three-dimensional image.

[0148] Fig.10 The scanning control method shown includes steps S1010 to S1050.

[0149] In step S1010, a second three-dimensional image of a scan object located on a scanning bed (such as bed 120) of a magnetic resonance imaging system is acquired by a 3D camera;

[0150] In step S1020, a plurality of feature points (eg Figure 4 feature point 401 in ).

[0151] In step S1030, based on the distribution information of the identified feature points, the pre-stored standard human body image (eg Figure 4 The image G1 in FIG. 1 is adjusted to a matching image adapted to the body features of the scanned object (eg Figure 4 Figure 1 shows the image P1 in Figure 1.

[0152] In step S1040, the selected region of interest (eg Figure 4 area 402 in the image).

[0153] In step S1050, the scanning bed is controlled to move so as to position the part of interest of the scan object corresponding to the selected region of interest (eg, the patient's chest corresponding to the region of interest 402) to a preset position.

[0154] Controlling the movement of the scanning bed may further include controlling the movement of the scanning bed at a variable speed. Fig.11 A flow chart of an embodiment of controlling the movement of a scanning bed is shown. Fig.11 As shown, it specifically includes steps S1110 to S1130.

[0155] In step S1110, the position information of the head of the scanned object in the moving direction of the scanning bed is calculated based on the second three-dimensional image, wherein the position information of the head of the scanned object in the moving direction of the scanning bed includes the distance between the head of the scanned object and the scanning center of the magnetic resonance imaging system.

[0156] In step S1120, the moving speed of the scanning bed at different positions is estimated based on a predetermined curve of the moving speed of the scanning bed changing with the position in the moving direction;

[0157] In step S1130 , the scanning bed is controlled to move at a variable speed based on the estimated moving speed.

[0158] like Fig.12 As shown, in one embodiment, the pre-scanning control method includes steps S1210 to S1220.

[0159] In step S1210, a third three-dimensional image captured by a 3D camera (for example, the 3D camera 310) is acquired, where the third three-dimensional image includes a scan object located on a scanning bed of the magnetic resonance imaging system and a surface receiving coil coupled to the scan object;

[0160] In step S1220, the surface receiving coil and the part of interest of the scanned object are identified in the third three-dimensional image, and it is calculated whether the position of the surface receiving coil matches the position of the part of interest; wherein, when the position of the surface receiving coil does not match the position of the part of interest, the magnetic resonance imaging system is controlled to issue a warning message.

[0161] Fifth embodiment

[0162] Fig.13 FIG. 1 is a schematic diagram showing the structure of a scanning control system according to an embodiment of the present invention. The scanning control system is used in a magnetic resonance imaging system. For example, the scanning control system can be used with Figure 1 The scanning control system may include a 3D camera 1310 , a processing device 1320 and a control device 1330 .

[0163] The 3D camera 1310 may be the same device as the 3D cameras 210, 310, 410, and 710, or a device installed and set in a similar manner. The 3D camera 1310 may be used to photograph the scanned object 16 located on the bed 120. For example, when the scanned object 16 lies flat or is positioned on the bed 120 in other postures that are conducive to scanning, a three-dimensional image of the scanned object 16 may be acquired through the 3D camera 1310. In one embodiment, when the 3D camera 1310 and the 3D camera 210 are the same device, the camera's shooting angle may be switched based on the recognition of different stages of magnetic resonance imaging. For example, when the current stage is recognized as patient positioning, the 3D camera may be focused on the scanned object in the first area, and when the current stage is recognized as the scanning stage, the 3D camera 1310 may be focused on the scanned object 16 on the bed 120. The switching of the 3D camera's shooting angle may be achieved, for example, by the control device 1330.

[0164] The processing device 1320 is used to recognize the body position information of the scanned object 16 based on the three-dimensional image taken by the 3D camera 1310, and the body position information is used to indicate the positioning direction and posture of the scanned object 16 on the bed 120. Fig.14 Multiple body positions of the scanned object are exemplarily shown.

[0165] The positioning direction may generally include, for example, head-first or feet-first, that is, when the moving bed 120 allows the scanned object on it to enter the scanning cavity from the outside, the head enters the scanning cavity first or the feet enters the scanning cavity first, for example, Fig.14The 4 positions in the middle and upper parts are head-first, and the 4 positions in the lower parts are feet-first. The positioning posture may include, for example, lying on your back, lying on your left side, lying on your right side, lying on your stomach, etc.

[0166] Typically, during the scanning phase of magnetic resonance imaging, doctors or technicians need to input corresponding body position information based on the patient's positioning direction and posture in order to subsequently select the appropriate slice position for image reconstruction. Sometimes the body position information input by the doctor or technician does not match the actual situation, causing the image reconstructed by the magnetic resonance imaging system to not correspond to the patient's lesion site. In this case, the patient often needs to be re-scanned, resulting in a waste of medical resources and emotional problems for the patient.

[0167] In this embodiment, the processing device 1320 can automatically identify the above-mentioned body position information of the scanned object 16 based on the three-dimensional image captured by the 3D camera 1310, so that the control device 1330 can set the scanning parameters related to the body position based on the identified body position information, which may include the body position information and other parameters that may change due to the change of the body position. In this way, the above-mentioned problems caused by manually inputting the body position information are avoided, and the scanning setting time can be accelerated. In one embodiment, the image reconstruction unit 141 can determine the slice position and angle of the image reconstruction based on the set body position related parameters to obtain an image that is convenient for disease diagnosis.

[0168] The body position information input in the traditional method is usually general information. Taking left lateral decubitus as an example, it may include a variety of different postures of the patient, which makes it difficult to more accurately correspond the slice position and angle selected in the subsequent reconstruction process to the lesion site.

[0169] Therefore, the processing device 1320 can further determine the slice position and angle of image reconstruction more accurately based on the body position of the scanned object 16 displayed in the three-dimensional image, and send the determined slice position and angle to the image reconstruction unit (e.g. Figure 1 The image reconstruction unit 141 in the image reconstruction unit 141), the slice position and angle are determined based on the actual body position of the scanned object 16 displayed in the three-dimensional image. For example, the selected slice may not be limited to being along the XY plane, but may also form an angle with the XY plane, so that the image reconstructed by the image reconstruction unit can correspond more accurately to the lesion site or the site of interest of the scanned object.

[0170] Sixth embodiment

[0171] Fig.15 FIG. 1 is a schematic diagram showing the structure of a scanning control system according to another embodiment of the present invention. The scanning control system is used in a magnetic resonance imaging system. For example, the scanning control system can be used with Figure 1The scanning control system may include a 3D camera 1510 , a processing device 1520 and a control device 1530 .

[0172] The 3D camera 1510 may be the same device as the 3D cameras 210 , 310 , 410 , 710 , and 1310 , or a device installed and configured in a similar manner.

[0173] The 3D camera 1510 is used to photograph the bed 120 and the scan object 16 located on the bed 120 to obtain a three-dimensional image. The scan object 16 is coupled to an RF receiving coil. The RF receiving coil may include a first receiving coil 171 disposed in the bed 120. The first receiving coil 171 includes a plurality of coil units 1711 arranged in an array. Figure 1 and Fig.15 The first receiving coil 171 can be set on the side of the bed 120 facing away from the scanning object 16, and the position relationship between it and the bed 120 is determined. The position relationship can be represented by second relative position information. Specifically, the second relative position information can include the position range or center position of the coil unit 1711 on the bed 120.

[0174] When the first receiving coil 171 is selected to be turned on, the processing device 1520 selects a suitable coil unit 1711 in the first receiving coil 171 to obtain image data of the scanned object. For example, the processing device 1520 can determine the first relative position information between the part of interest of the scanned object 16 and the bed 120 based on the three-dimensional image captured by the 3D camera 1510. The first relative position information can specifically represent the position range or center position of the region of interest 163 of the scanned object 16 on the bed 120. The processing device 1520 can identify the bed and the region of interest 163 of the scanned object in the three-dimensional image, and calculate the positional relationship between the identified region of interest 163 and the bed 120 as the above-mentioned first relative position information.

[0175] The processing device 1520 also determines the relative position information between the part of interest 162 of the scanned object 16 and the first receiving coil 171 based on the first relative position information and the second relative position information, and determines the coil unit 1711 that needs to be turned on in the first receiving coil 171 based on the relative position information between the part of interest 162 of the scanned object 16 and the first receiving coil 171. For example, the processing device 1520 determines the coil unit 1711 that is closer to the area of ​​interest 163 of the scanned object 16.

[0176] The control device 1530 is used to turn on the determined coil unit 1711 . Specifically, the control device 1530 turns on the coil unit 1711 by controlling a switching switch of the coil unit 1711 .

[0177] The above describes an example of automatically selecting a coil unit when the first receiving coil 171 (i.e., a receiving coil coupled to the bed 120 and determined relative to the position of the bed 120) is used. In the following example, an example of automatically selecting a coil and a coil unit when the second receiving coil 172 is used will also be described. The second receiving coil 172 can be a receiving coil set on the body of the scanned object 16, which also includes a plurality of coil units 1721 arranged in a matrix. According to different imaging requirements, it can be laid flat / covered to fit one side of the body of the scanned object 16, or it can be wrapped around / wrapped on a body part of the scanned object 16. In the former method, the second receiving coil is generally covered on the upper side of the scanned object (the side away from the bed 120), and the first receiving coil is used in combination during scanning to obtain imaging data of the scanned object. In the latter method, only the second receiving coil can be used to obtain imaging data without using the first receiving coil. However, doctors or technicians sometimes input information that does not match the actual coil coupling method when setting up. For example, when the second surface coil is flat, if the doctor or technician sets it to use only the second surface coil, the acquired imaging data is incomplete, which seriously affects the quality of the reconstructed image, and the scanning process usually needs to be re-executed.

[0178] In the example of this embodiment, the processing device 1520 can identify the coupling mode between the second receiving coil 172 and the scanned object 16 based on the three-dimensional image captured by the 3D camera 1510, and select all or one of the first receiving coil 171 and the second receiving coil 172 based on the coupling mode between the second receiving coil 172 and the scanned object 16, and the control device 1530 is used to turn on the selected coils of the selected first receiving coil 171 and the second receiving coil 172, specifically, it can be achieved by controlling the switching switches of the first receiving coil and the second receiving coil. For example, when the second receiving coil 172 is coupled to the scanned object in a tiled manner, the first receiving coil and the second receiving coil can be selected to be turned on; when the second receiving coil 172 is coupled to the scanned object in a surrounding manner, only the second receiving coil can be selected to be turned on.

[0179] In the example of this embodiment, when the second receiving coil is selected, the processing device 1520 further determines the relative position information between the part of interest 162 of the scanned object 16 and the second receiving coil 172 based on the three-dimensional image taken by the 3D camera 1510, and determines the coil unit 1721 that needs to be turned on in the second receiving coil 172 based on the relative position information between the part of interest 162 of the scanned object 16 and the second receiving coil 172. Similarly, the coil unit 1721 that is closer to the area of ​​interest 163 of the scanned object 16 can be determined.

[0180] Seventh embodiment

[0181] Fig.16 FIG. 1 is a schematic diagram showing the structure of a scanning control system according to another embodiment of the present invention. The scanning control system can be used as follows: Figure 1 The scanning control system may include a 3D camera 1610 , a processing device 1620 and a control device 1630 .

[0182] The 3D camera 1610 may be the same device as the 3D cameras 210 , 310 , 410 , 710 , 1310 , and 1510 , or a device installed and configured in a similar manner.

[0183] The 3D camera 1610 is used to photograph the second area 102 to obtain a first environment image when the scanning process is not started or ended. As described above, the second area 102 includes the positioning area of ​​the bed 120.

[0184] The processing device 1620 is used to compare the first environment image with the pre-stored standard environment image, and indicate the maintenance status based on the comparison result. The above standard environment image shows the on-site environment of the first area in the normal maintenance state, for example, it may include the relative position and placement posture of each component in the second area. If the scanning task is not currently being performed, on-site maintenance can be performed. After the maintenance is completed, the current image taken by the 3D camera 1610 can be compared with the standard environment image to determine whether there is improper maintenance. For example, when it is found that there is an error in the placement position or posture in the current image, or there are extra components, parts or debris compared to the standard environment image, it means that the maintenance state is abnormal. At this time, the control device 1630 can be used to control the magnetic resonance imaging system, such as a sound device, a display device or a light-emitting device, to issue a corresponding warning. If the current image is consistent with the display content of the standard environment image, it means that the maintenance state is normal.

[0185] Combination Figure 1 and Fig.16 As shown, similarly, the third area 103 can also be photographed by the 3D camera 1640 to obtain a second environment image, and the second environment image is compared with another pre-stored standard image, and the maintenance status is indicated based on the comparison result.

[0186] Fig.17 and Fig.18 Flowcharts of a scanning control method for a magnetic resonance imaging system according to an embodiment are respectively shown.

[0187] like Fig.17 As shown, the method includes steps S1710-1730.

[0188] In step S1710, a three-dimensional image of a scan object located on a scanning bed (such as bed 120) of a magnetic resonance imaging system is acquired by a first 3D camera;

[0189] In step S1720, the body position information of the scanned object is recognized based on the three-dimensional image.

[0190] In step S1730, scanning parameters related to the body position are set based on the body position information.

[0191] Optionally, the method may further include: determining a slice position and angle for image reconstruction based on the body position of the scanned object displayed in the three-dimensional image, and sending the determined slice position and angle to an image reconstruction unit of the magnetic resonance imaging system.

[0192] like Fig.18 As shown, the method includes steps S1810 to S1830.

[0193] In step S1810, a scanning bed of a magnetic resonance imaging system and a scanning object on the scanning bed are acquired through a first 3D camera to acquire a three-dimensional image, wherein the scanning object is coupled with an RF receiving coil (e.g., a first receiving coil 171 and a second receiving coil 172), and the RF receiving coil includes a plurality of coil units arranged in an array (e.g., coil units 1711 and 1721);

[0194] In step S1820, relative position information between the part of interest of the scanned object and the RF receiving coil is determined based on the three-dimensional image, and a coil unit that needs to be turned on is selected in the RF receiving coil based on the determined relative position information.

[0195] In step S1830, the selected coil unit is turned on.

[0196] The method may further include: identifying a coupling mode between the second receiving coil and the scanned object based on the three-dimensional image, and selecting all or one of the first receiving coil and the second receiving coil based on the coupling mode between the second receiving coil and the scanned object; and turning on the selected coil between the first receiving coil and the second receiving coil.

[0197] When the first receiving coil is selected, a required coil unit is selected in the first receiving coil based on the relative position information between the part of interest of the scanned object and the first receiving coil. When the second receiving coil is selected, a required coil unit is selected in the second receiving coil based on the relative position information between the part of interest of the scanned object and the second receiving coil.

[0198] The method may further include:

[0199] Acquiring a first environment image of a first area captured by a first 3D camera when the scanning process is not started or is completed;

[0200] comparing the first environment image with a pre-stored first standard environment image; and,

[0201] A maintenance status of the magnetic resonance imaging system is indicated based on a comparison result between the first environment image and the first standard environment image.

[0202] The method may further include:

[0203] Acquiring a second environment image of a third area (e.g., the third area 103) captured by a second 3D camera when the scanning process is not started or is completed, wherein the first 3D camera and the second 3D camera are respectively located on two sides of a magnet assembly of the magnetic resonance imaging system, and the third area includes an area located outside a scanning cavity of the magnetic resonance imaging system and opposite to a rear end of the scanning cavity;

[0204] comparing the third environment image with a pre-stored second standard environment image; and,

[0205] The maintenance status of the magnetic resonance imaging system is indicated based on a comparison result between the third environment image and the second standard environment image.

[0206] The above various embodiments describe the use of a 3D camera to capture images of different areas in a magnetic resonance scanning room, and based on various analyses of these images and the automatic control of the magnetic resonance imaging system based on the analysis results, so that the pre-scanning and scanning processes of magnetic resonance imaging can be performed more accurately and efficiently, for example, by more accurately indicating the positioning guide mark to achieve accurate and rapid patient positioning; by indicating the positioning state of the receiving coil to help the operator to set the surface receiving coil more quickly and accurately; by indicating the matching state of the receiving coil and the part of interest, avoid image quality problems caused by position mismatch; by estimating the moving speed of the scanning bed, ensure the safety of the patient while moving the patient quickly; by automatically detecting the body position, avoid waste of resources and image quality problems caused by incorrect body position setting, and more accurate body position information enables reconstruction of images that better reflect the patient's lesions; by automatically detecting the coupling mode of the coil and the object, automatically select the coil, and automatically select the coil unit according to the relative position of the coil and the part of interest, avoid waste of resources and image quality problems caused by incorrect selection of the coil and the coil unit; by combining the real image of the patient with the standard human body structure image, achieve rapid selection of the area of ​​interest.

[0207] The following embodiment will describe an example of implementing magnetic resonance imaging using various embodiments of the present invention, wherein after the previous imaging process is completed, the current imaging process is started based on user operation, and a pre-scan is performed:

[0208] The 3D camera lens is controlled to aim at the first area. The 3D camera can be controlled to photograph patients in the first area based on user operations. The 3D camera can also be used to monitor whether there are patients in the first area. If so, a first three-dimensional image is automatically acquired, and a positioning mark is projected on the bed 120 based on the analysis of the first three-dimensional image, and the bed 120 is adjusted to a height suitable for the patient.

[0209] The lens of the 3D camera is directed to the area where the bed 120 is located, automatically or based on user operation.

[0210] The patient sits at the positioning mark and is then positioned on the bed 120 according to the body position requirements.

[0211] The second three-dimensional image is acquired by photographing the patient on the bed 120 with a 3D camera, and the region of interest is automatically determined and selected in combination with a pre-stored standard human body image. This step can replace the scout scan or be performed in combination with the scout scan.

[0212] Based on the analysis of the second three-dimensional image, it is determined whether the patient's to-be-scanned part (part of interest) is positioned at a suitable location. If not, the operator or the patient is prompted until the part of interest is positioned.

[0213] After the surface coil covers or surrounds a part of the patient's body, based on the operator's operation or automatic monitoring results, the 3D camera is controlled to capture a third three-dimensional image, which includes the bed, the patient, and the surface coil on the patient's body. Based on the analysis of the third three-dimensional image, it is determined whether the surface coil is positioned relative to the part of interest. If not, the operator is prompted to wait until the surface coil is positioned.

[0214] The current relative position of the patient's head is determined based on the second three-dimensional image, the third three-dimensional image, or another three-dimensional image obtained by photographing the patient on the bed 120 with a 3D camera, and the movement speed of the patient at different travels in the direction of travel (Z direction) is estimated according to the relative position of the head.

[0215] To perform a scan:

[0216] The patient's body position is determined based on the analysis of the third three-dimensional image and body position-related parameters are automatically set.

[0217] The coupling mode of the surface coil and the patient is determined based on the analysis of the third three-dimensional image. For example, if it is a covering mode, the surface coil and the receiving coil set in the bed 120 are selected to be turned on; if it is a surrounding mode, only the surface coil is selected to be turned on.

[0218] A coil unit is further selected from among the selected coils based on the analysis of the third three-dimensional image.

[0219] The bed 120 is controlled to move at an estimated speed to position the patient's area of ​​interest at a preset position, for example, relative to the scanning center.

[0220] Image data during scanning is acquired via the selected coil unit, and a reconstruction unit performs image reconstruction based on the image data, wherein the angle and position of the slice are selected according to the body position information.

[0221] The bed 120 is controlled to move according to the estimated speed to move the patient out of the scanning cavity 116 .

[0222] End the imaging process.

[0223] The order of description of the steps in the above examples is not intended to limit the actual execution order, and there are many variable embodiments to complete the imaging process.

[0224] In the various embodiments above, the processing unit and the control unit include a circuit configured to perform one or more tasks, functions or steps discussed herein. In various embodiments, the processing unit may be integrated with the data processing unit 120 of the magnetic resonance imaging system, and the control unit may be integrated with the control unit 130 of the magnetic resonance imaging system. The "processing unit" and "control unit" used herein are not intended to be necessarily limited to a single processor or computer. For example, the processing unit and the control unit may include multiple processors, ASICs, FPGAs and / or computers, which may be integrated into a common housing or unit, or may be distributed in various units or housings. The depicted processing unit and control unit include a memory. The memory 130 may include one or more computer-readable storage media. For example, the memory 130 may store information about system characteristics (e.g., information about spatial gradients), images (e.g., standard human images), algorithms or processes for executing any of the above embodiments, etc. Further, the process flow and / or flowchart (or aspects thereof) discussed herein may represent one or more instruction sets stored in the memory for guiding scan control or pre-scan control.

[0225] As used herein, an element or step described in the singular and preceded by the word "one" or "an" should be understood as not excluding the plural number of the element or step, unless such exclusion is explicitly stated. In addition, reference to "one embodiment" of the present invention is not intended to be interpreted as excluding the existence of additional embodiments that simultaneously incorporate the described features. Moreover, unless explicitly stated to the contrary, an embodiment "comprising", "including", "having" an element or multiple elements with a specific property may include additional such elements that do not have the property. The terms "including" and "in which" are used as the concise language equivalents of the corresponding terms "comprising" and "wherein". In addition, in the appended claims, the terms "first", "second" and "third" etc. are used only as markers and are not intended to impose numerical requirements or specific positional order on their objects.

[0226] This written description uses examples to disclose the invention, including the best mode, and also enables a person of ordinary skill in any relevant art to implement the invention, including making and using any device or system and performing any covered method. The scope of patent protection for the invention is defined by the claims and may include other examples known to those skilled in the art. If they have structural elements that are indistinguishable from the literal language of the claims, or if they include equivalent structural elements that are insubstantially different from the literal language of the claims, it is intended that such other examples fall within the scope of the claims.

Claims

1. A pre-scanning control system for a magnetic resonance imaging system, wherein a positioning guidance device is coupled to the magnetic resonance imaging system, and the pre-scanning control system comprises: A 3D camera is used to capture a first three-dimensional image of a scanned object in a first area outside a scanning cavity of the magnetic resonance imaging system at a first shooting angle, wherein the first three-dimensional image includes at least a positioning part and a part of interest of the scanned object; a processing device, which is used to determine first positioning information of the scanned object relative to the magnetic resonance scanning bed when the scanned object is subjected to imaging scanning based on the positional relationship between the positioning part and the part of interest in the first three-dimensional image; and A control device, used for controlling the positioning guidance device to issue positioning guidance information based on the first positioning information; The 3D camera is further used to capture a three-dimensional image of a scan object located on a scanning bed of the magnetic resonance imaging system and an RF receiving coil coupled to the scan object at a second shooting angle; The processing device is further used to determine the relative position information between the part of interest and the RF receiving coil based on the three-dimensional image captured at the second shooting angle, and select the coil unit that needs to be turned on in the RF receiving coil based on the determined relative position information; The control device is further used to turn on the selected coil unit.

2. The pre-scanning control system according to claim 1, wherein: The processing device is used to calculate the distance between the positioning part and the part of interest in the first three-dimensional image, and calculate the first positioning information based on the distance between the positioning part and the part of interest and predetermined second positioning information of the part of interest relative to the magnetic resonance scanning bed.

3. The pre-scanning control system according to claim 2, wherein: The second positioning information is determined based on a position of a receiving coil matched with the site of interest relative to the magnetic resonance scanning bed, wherein the receiving coil is arranged in the magnetic resonance scanning bed.

4. The pre-scanning control system according to claim 1, wherein: The first area is opposite to the patient entrance of the scanning cavity and has a space between the first area and the scanning bed of the magnetic resonance imaging system.

5. The pre-scanning control system according to claim 1, wherein: The positioning part is the buttocks of the scanned object.

6. The pre-scanning control system according to claim 1, wherein: The first three-dimensional image includes at least two reference parts of the scanned object, the processing device is used to determine the height of the scanning bed of the magnetic resonance imaging system based on the positional relationship between the two reference parts in the first three-dimensional image, and the control device is used to control the scanning bed to rise or fall to the height.

7. The pre-scanning control system according to claim 6, wherein: The processing device determines the height of the scanning bed based on a distance between two reference locations in the first three-dimensional image.

8. The pre-scanning control system according to claim 7, wherein: The two reference parts are respectively the knee and the foot of the scanned object.

9. A pre-scanning control method for a magnetic resonance imaging system, wherein the magnetic resonance imaging system is coupled with a positioning guidance device, the pre-scanning control method comprising: Acquire a first three-dimensional image of a scanned object in a first area outside a scanning cavity of the magnetic resonance imaging system, which is captured by a 3D camera at a first shooting angle, wherein the first three-dimensional image includes at least a positioning site and a site of interest of the scanned object; determining first positioning information of the scanned object relative to the magnetic resonance scanning bed when the scanned object is receiving imaging scanning based on the positional relationship between the positioning part and the part of interest in the first three-dimensional image; as well as, Controlling the positioning guidance device to issue positioning guidance information based on the first positioning information; Wherein, the method further comprises: acquiring a three-dimensional image of a scan object located on a scanning bed of the magnetic resonance imaging system and an RF receiving coil coupled to the scan object, which is photographed at a second photographing angle by the 3D camera; determining relative position information between the site of interest and the RF receiving coil based on the three-dimensional image captured at the second shooting angle, and selecting a coil unit that needs to be turned on in the RF receiving coil based on the determined relative position information; and, The selected coil unit is turned on.

10. The method of claim 9, wherein: Determining first positioning information of the scanned object relative to the magnetic resonance scanning bed when receiving imaging scanning based on the positional relationship between the positioning part and the part of interest in the first three-dimensional image includes: The distance between the positioning site and the site of interest in the first three-dimensional image is calculated, and the first positioning information is calculated based on the distance between the positioning site and the site of interest and predetermined second positioning information of the site of interest relative to the magnetic resonance scanning bed.

11. The method of claim 10, wherein: The second positioning information is determined based on a position of a receiving coil matched with the site of interest relative to the magnetic resonance scanning bed, wherein the receiving coil is disposed on the magnetic resonance scanning bed.

12. The method of claim 9, wherein: The first area is opposite to the patient entrance of the scanning cavity and has a space between the first area and the scanning bed of the magnetic resonance imaging system.

13. The method of claim 9, wherein: The positioning part is the buttocks of the scanned object.

14. The method of claim 9, wherein: The first three-dimensional image includes at least two reference parts of the scanned object, and the method further includes: determining the height of the scanning bed of the magnetic resonance imaging system based on the positional relationship between the two reference parts in the first three-dimensional image; and The scanning bed is controlled to rise or fall to the height.

15. The method of claim 14, wherein: The height of the scanning bed is determined based on a distance between two reference locations in the first three-dimensional image.

16. The method of claim 14, wherein: The two reference parts are respectively the knee and the foot of the scanned object.

17. A pre-scanning control system for a magnetic resonance imaging system, comprising: A storage device storing a standard human body image having a plurality of human anatomical structures; a 3D camera, the 3D camera being used to capture a second three-dimensional image of a scan object located on a scanning bed of the magnetic resonance imaging system; a processing device for identifying a plurality of feature points in the second three-dimensional image, and adjusting the standard human body image based on distribution information of the identified feature points to obtain a matching image adapted to the body features of the scanned object; the processing device is also used to identify a region of interest selected in the matching image; and, A control device, used for controlling the movement of the scanning bed to position the part of interest of the scanned object corresponding to the selected region of interest to a preset position; Wherein, the 3D camera is further used for photographing the scanned object and the surface receiving coil to obtain a third three-dimensional image when the scanned object is coupled with a surface receiving coil; The processing device is further used to identify the surface receiving coil and the region of interest of the scanned object in the third three-dimensional image, determine the relative position information between the region of interest and the surface receiving coil, and select the coil unit that needs to be turned on in the surface receiving coil based on the determined relative position information; The control device is further used to turn on the selected coil unit.

18. The pre-scanning control system of claim 17, wherein: The processing device is further used to calculate the position information of the head of the scanned object in the moving direction of the scanning bed based on the second three-dimensional image, and estimate the moving speed of the scanning bed at different positions based on a predetermined curve of the moving speed of the scanning bed changing with the position in the moving direction; The control device is used to control the scanning bed to move at a variable speed based on the estimated moving speed.

19. The pre-scanning control system of claim 18, wherein: The position information of the head of the scan object in the moving direction of the scanning bed includes the distance between the head of the scan object and the scanning center of the magnetic resonance imaging system.

20. The pre-scanning control system of claim 17, wherein: The 3D camera is also used to capture a third three-dimensional image of a scan object located on a scanning bed of the magnetic resonance imaging system and a surface receiving coil coupled to the scan object; The processing device is used to identify the surface receiving coil and the part of interest of the scanned object in the third three-dimensional image, and calculate whether the position of the surface receiving coil matches the position of the part of interest; When the position of the surface receiving coil does not match the position of the site of interest, the control device is used to control the magnetic resonance imaging system to issue a warning message.

21. A pre-scanning control method for a magnetic resonance imaging system, comprising: acquiring a second three-dimensional image of a scan object located on a scanning bed of the magnetic resonance imaging system, taken by a 3D camera; identifying a plurality of feature points in the second three-dimensional image; adjusting a pre-stored standard human image into a matching image adapted to the body features of the scanned object based on distribution information of the identified feature points, wherein the standard human image has a plurality of human anatomical structures; identifying a selected region of interest in the matching image; and, Controlling the scanning bed to move so as to position the part of interest of the scanned object corresponding to the selected region of interest to a preset position; Wherein, the method further comprises: When the scan object is coupled with a surface receiving coil, acquiring a third three-dimensional image having the scan object and the surface receiving coil captured by the 3D camera; identifying the surface receiving coil and the region of interest of the scanned object in the third three-dimensional image, determining relative position information between the region of interest and the surface receiving coil, and selecting a coil unit that needs to be turned on in the surface receiving coil based on the determined relative position information; and, The selected coil unit is turned on.

22. The method of claim 21, wherein: Controlling the movement of the scanning bed also includes: Calculating position information of the head of the scan object in a moving direction of the scanning bed based on the second three-dimensional image; estimating the moving speed of the scanning bed at different positions based on a predetermined curve of the moving speed of the scanning bed versus the position in the moving direction; The scanning bed is controlled to move at a variable speed based on the estimated movement speed.

23. The method of claim 22, wherein: The position information of the head of the scan object in the moving direction of the scanning bed includes the distance between the scan object and the scanning center of the magnetic resonance imaging system.

24. The method of claim 21, wherein: Also includes: Calculating whether the position of the surface receiving coil matches the position of the site of interest, wherein when the position of the surface receiving coil does not match the position of the site of interest, controlling the magnetic resonance imaging system to issue a warning message.

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