Magnetic resonance equipment scanning parameter correction method, ablation device and ablation system

Abstract

The invention provides a magnetic resonance equipment scanning parameter correction method, device and system, and the method comprises the steps: carrying out the rapid magnetic resonance imaging of a target region periodically, and obtaining a group of continuous magnetic resonance images in each period; for each group of continuous magnetic resonance images, establishing a three-dimensional temperature diagram according to a phase diagram in the magnetic resonance images, and establishing a three-dimensional amplitude diagram according to an amplitude diagram in the magnetic resonance images; and for each period, according to the registration relationship between the three-dimensional amplitude images of the current period and the previous period, generating a new scanning parameter for rapid magnetic resonance imaging of the next period. According to the method, a group of continuous magnetic resonance images are obtained through rapid magnetic resonance imaging to be used for reconstructing the three-dimensional temperature diagram and the three-dimensional amplitude diagram, the three-dimensional structure and the temperature state can be observed conveniently, meanwhile, the current scanning parameters are corrected according to the registration relation of the three-dimensional amplitude diagram of the current period and the three-dimensional amplitude diagram of the previous period, positioning sequence scanning does not need to be conducted again, and the accuracy is high. And the time of the laser interstitial thermotherapy process is saved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly to a method for correcting scanning parameters of a magnetic resonance device, an ablation device and an ablation system. Background Art

[0002] Magnetic resonance-guided laser interstitial thermotherapy (MRgLITT) is a method of using a laser to ablate a target lesion. It uses an optical fiber to introduce light energy into the target tissue. As the irradiation time increases, the temperature of the target tissue rises, and finally reaches the temperature required for thermal ablation, thereby eliminating the lesion. During the operation, a magnetic resonance device is used to monitor the temperature state of the target tissue to ablate the target area as much as possible while avoiding ablation of normal tissue. Magnetic resonance-guided laser interstitial thermotherapy has advantages such as minimally invasive, low risk and quick recovery, and provides new treatment options for various diseases (such as brain tumors, epilepsy, etc., liver, spleen, prostate tumors, etc.).

[0003] Since the light-emitting part at the end of the optical fiber emits laser light towards the target tissue in a direction substantially perpendicular to the optical fiber, in order to better observe the ablation state, the current commonly adopted solution is to set the scanning parameters of the magnetic resonance device so that the magnetic resonance device acquires magnetic resonance images (for example, acquires 3 cross-sections) at several mutually parallel cross-sections perpendicular to the optical fiber direction and passing through the target tissue, for generating a temperature map. The reason for collecting magnetic resonance images only at several cross-sections passing through the target area is to increase the update frequency of the temperature state and meet the real-time requirement of temperature monitoring.

[0004] The problem faced by the prior art is that when the patient moves, the spatial positions of the target tissue and the optical fiber change, and a larger range of positioning sequence scanning needs to be performed again (for example, in an application example, it takes about 5 minutes) to re-determine the position of the target area and the position of the optical fiber, and determine new scanning parameters according to the positions of the target area and the optical fiber. The above process of positioning sequence scanning and re-determining scanning parameters takes a long time and requires interrupting the ablation process.

[0005] For the above defects, the present invention proposes a method, device and system for correcting scanning parameters of a magnetic resonance device. Summary of the Invention

[0006] The present invention provides a method, device and system for correcting scanning parameters of a magnetic resonance device, so as to solve the defects in the prior art, improve the scanning efficiency of magnetic resonance images, and shorten the operation time.

[0007] The present invention provides a method for correcting scanning parameters of a magnetic resonance device, including:

[0008] Periodically perform fast magnetic resonance imaging on the target area, and obtain a set of consecutive magnetic resonance images in each period;

[0009] For each set of consecutive magnetic resonance images, establish a three-dimensional temperature map based on the phase map in the magnetic resonance images, and establish a three-dimensional amplitude map based on the amplitude map in the magnetic resonance images;

[0010] For each period, generate new scanning parameters according to the registration relationship between the three-dimensional amplitude maps of the current period and the reference period, for the fast magnetic resonance imaging in the next period.

[0011] According to a method for correcting scanning parameters of a magnetic resonance device provided by the present invention, before periodically performing fast magnetic resonance imaging on the target area and obtaining a set of consecutive magnetic resonance images in each period, it further includes:

[0012] Obtain the positioning sequence scanning image, establish a positioning three-dimensional structure diagram according to the positioning sequence scanning image, and register the positioning three-dimensional structure diagram with the preoperative three-dimensional image to determine the position of the target area; wherein, the target area is outlined or automatically segmented in the preoperative three-dimensional image;

[0013] Determine the initial scanning parameters according to the position of the target area, or determine the initial scanning parameters according to the user input instruction.

[0014] According to a method for correcting scanning parameters of a magnetic resonance device provided by the present invention, when determining the initial scanning parameters according to the position of the target area, it further includes:

[0015] Take the direction of the thinnest sandwich as the initial scanning direction according to the shape of the target area; wherein, the thinnest sandwich refers to two parallel planes that sandwich the target area range with the smallest plane spacing.

[0016] According to a method for correcting scanning parameters of a magnetic resonance device provided by the present invention, when periodically performing fast magnetic resonance imaging on the target area and obtaining a set of consecutive magnetic resonance images in each period, it includes:

[0017] Determine the target area to be sampled in the current period according to the preset magnetic resonance downsampling rule;

[0018] Perform magnetic resonance scanning on the target area to obtain the magnetic resonance image of the target area;

[0019] Obtain the consecutive magnetic resonance images in the current period according to the magnetic resonance image of the target area.

[0020] According to a method for correcting scanning parameters of a magnetic resonance device provided by the present invention, the preset magnetic resonance downsampling rule is inter-slice downsampling and / or intra-slice downsampling.

[0021] A method for correcting scanning parameters of a magnetic resonance device according to the present invention, obtaining a series of consecutive magnetic resonance images of the current period based on the magnetic resonance image of the target area, includes:

[0022] Based on the magnetic resonance image of the target area, obtaining a series of consecutive magnetic resonance images covering the target area by interpolation; or,

[0023] Based on the magnetic resonance image of the target area, obtaining a series of consecutive magnetic resonance images covering the target area by combining the magnetic resonance images of its complementary period.

[0024] A method for correcting scanning parameters of a magnetic resonance device according to the present invention, performing fast magnetic resonance imaging on the target area periodically, and obtaining a set of consecutive magnetic resonance images in each period, includes:

[0025] Scanning the target area periodically through a fast magnetic resonance imaging sequence;

[0026] Using the reference period to correct the magnetic resonance image of the current period to obtain a corrected magnetic resonance image.

[0027] A method for correcting scanning parameters of a magnetic resonance device according to the present invention, the magnetic resonance image of the reference period is a positioning sequence scan image obtained by pre-scanning a reference area, and the reference area covers the target area.

[0028] A method for correcting scanning parameters of a magnetic resonance device according to the present invention, the fast magnetic resonance imaging sequence is a gradient echo sequence, and the positioning sequence is a spin echo sequence.

[0029] A method for correcting scanning parameters of a magnetic resonance device according to the present invention, the reference period is any corrected period, and using the reference period to correct the magnetic resonance image of the current period, includes:

[0030] Obtaining distortion correction information according to the first position of the target structure in the magnetic resonance image of the reference period and the second position of the target structure in the magnetic resonance image of the reference period; wherein, the reference period is a positioning sequence scan image obtained by pre-scanning a reference area, and the reference area covers the target area;

[0031] Correcting the magnetic resonance image of the current period according to the distortion correction information.

[0032] A method for correcting scanning parameters of a magnetic resonance device according to the present invention, for each set of consecutive magnetic resonance images, after establishing a three-dimensional temperature map according to the phase map in the magnetic resonance image and establishing a three-dimensional amplitude map according to the amplitude map in the magnetic resonance image, the method further includes:

[0033] Comparing the current period with the background area of the previous period;

[0034] If the change in the cumulative gray value of the background region does not exceed a preset threshold, then enter the next cycle and perform the step of periodically performing fast magnetic resonance imaging on the target area;

[0035] If the change in the cumulative gray value of the background region exceeds the preset threshold, jump to the step of generating new scan parameters according to the registration relationship between the three-dimensional amplitude maps of the current cycle and the reference cycle.

[0036] According to a method for correcting scan parameters of a magnetic resonance device provided by the present invention, generating new scan parameters according to the registration relationship between the three-dimensional amplitude maps of the current cycle and the reference cycle includes:

[0037] Register the background regions of the three-dimensional amplitude maps of the current cycle and the reference cycle, and perform correction based on this registration relationship on the basis of the scan parameters of the reference cycle to obtain new scan parameters.

[0038] According to a method for correcting scan parameters of a magnetic resonance device provided by the present invention, for each set of consecutive magnetic resonance images, after establishing a three-dimensional temperature map according to the phase map in the magnetic resonance image and establishing a three-dimensional amplitude map according to the amplitude map in the magnetic resonance image, the method further includes:

[0039] Judge the inclusion situation of the target area in the three-dimensional amplitude map of the current cycle;

[0040] If the three-dimensional amplitude map of the current cycle completely contains the target area, enter the next cycle and perform periodic fast magnetic resonance imaging on the target area;

[0041] If the three-dimensional amplitude map of the current cycle partially contains the target area, jump to the step of generating new scan parameters according to the registration relationship between the three-dimensional amplitude maps of the current cycle and the reference cycle;

[0042] If the three-dimensional amplitude map of the current cycle completely does not contain the target area, register the three-dimensional amplitude map of the current cycle with the positioning three-dimensional structure diagram, and determine new scan parameters according to this registration relationship; wherein, the positioning three-dimensional structure diagram is a three-dimensional amplitude map established according to the positioning sequence scan image.

[0043] According to a method for correcting scan parameters of a magnetic resonance device provided by the present invention, generating new scan parameters according to the registration relationship between the three-dimensional amplitude maps of the current cycle and the reference cycle includes:

[0044] In the three-dimensional amplitude map of the current cycle, if the images at some tomographic positions match those of the previous cycle and the images at the remaining tomographic positions do not match those of the previous cycle, do not use the magnetic resonance images of the current cycle for registration, register the three-dimensional amplitude maps of the next cycle and the previous cycle, and perform correction based on this registration relationship on the basis of the scan parameters of the previous cycle to obtain new scan parameters.

[0045] A method for correcting scanning parameters of a magnetic resonance device according to the present invention generates new scanning parameters according to the registration relationship between the three-dimensional amplitude maps of the current cycle and the reference cycle, including:

[0046] In the three-dimensional amplitude of the current cycle, when the images of some tomographic positions match those of the previous cycle and the images of the remaining tomographic positions do not match those of the previous cycle, the scanning parameters of the previous cycle are corrected according to the registration relationship between the images of the remaining tomographic positions and the previous cycle to obtain new scanning parameters.

[0047] The present invention also provides an ablation device, including: a host computer, which stores executable instructions, and when the executable instructions are executed, the magnetic resonance device parameter correction method of any one of the foregoing is implemented to correct the scanning parameters of the magnetic resonance device. The ablation device can use various energies, such as laser, confocal ultrasound, radio frequency, etc.

[0048] The present invention also provides a magnetic resonance-guided laser ablation system, including: a magnetic resonance device, and the foregoing laser ablation device.

[0049] A method, device, and system for correcting scanning parameters of a magnetic resonance device provided by the present invention have at least one or more of the following beneficial effects:

[0050] 1. By quickly acquiring continuous magnetic resonance images through magnetic resonance and reconstructing a three-dimensional temperature map, it is convenient for users to understand the temperature status at each position, making temperature monitoring more comprehensive and subsequent evaluation of the ablation status more accurate;

[0051] 2. Based on the registration of the three-dimensional amplitude maps of the current cycle and the reference cycle, the movement parameters of the patient are conveniently determined, and the scanning parameters are corrected accordingly, without repositioning sequence scanning, avoiding interruption of the ablation (such as laser, confocal ultrasound, etc.) process and shortening the operation time;

[0052] 3. Based on the background area judgment, it is possible to quickly judge whether the patient has moved, without the need for a complex registration process every time;

[0053] 4. Since a three-dimensional temperature map and a three-dimensional amplitude map are reconstructed, when the three target areas do not exceed the current magnetic resonance scanning range, there is no need to adjust the scanning parameters or re-perform positioning sequence scanning, improving the operation efficiency;

[0054] 5. In the case where the patient moves greatly, by registering the three-dimensional amplitude map of the current cycle with the three-dimensional amplitude map established based on the positioning sequence scanning to determine new scanning parameters, there is still no need to re-perform positioning sequence scanning, improving the operation efficiency;

[0055] 6. The magnetic resonance images are quickly obtained through inter-layer downsampling / intra-layer downsampling, and continuous magnetic resonance images are obtained through the method of "repairing", shortening the imaging cycle and meeting the real-time requirement for monitoring temperature during ablation (such as laser, confocal ultrasound, etc.).

[0056] 7. The target area is scanned by a fast magnetic resonance imaging sequence, and the obtained magnetic resonance images are corrected using a reference cycle to obtain continuous magnetic resonance images, shortening the imaging cycle and meeting the real-time requirement for monitoring temperature during ablation (such as laser, confocal ultrasound, etc.). BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0058] Figure 1 is a schematic flowchart of a method for correcting scanning parameters of a magnetic resonance device provided by the present invention;

[0059] Figure 2 is a schematic diagram of a three-dimensional amplitude map obtained by acquisition and processing under the condition that the patient moves, provided by the present invention;

[0060] Figure 3 is a program flowchart corresponding to a preferred embodiment of a method for correcting scanning parameters of a magnetic resonance device provided by the present invention;

[0061] Figure 4 is a schematic structural diagram of a laser ablation device provided by the present invention;

[0062] Figure 5 is a schematic structural diagram of a magnetic resonance-guided laser ablation system provided by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0063] To make the objectives, technical solutions and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions in the present invention in conjunction with the drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments in the present invention fall within the scope of protection of the present invention.

[0064] The following will describe a method, device and system for correcting scanning parameters of a magnetic resonance device of the present invention in conjunction with Figures 1 - 5 description of a method, device and system for correcting scanning parameters of a magnetic resonance device of the present invention.

[0065] Figure 1 A method for correcting scanning parameters of a magnetic resonance device provided by the present invention is used for magnetic resonance-guided laser interstitial thermotherapy. The execution subject of this method is the main body of the laser ablation device, such as Figure 1 shown, this method includes:

[0066] S11. Rapid magnetic resonance imaging is periodically performed on the target area, and a set of continuous magnetic resonance images is obtained in each cycle;

[0067] Specifically, during the intraoperative ablation process, we only focus on the temperature status of the target area to be ablated and its nearby tissues. Therefore, performing magnetic resonance scanning within a limited range for the target area (i.e., at least covering the target area) can shorten the magnetic resonance scanning time and increase the update frequency of the temperature status. By setting the current scanning parameters, the magnetic resonance device can acquire a set of continuous magnetic resonance images covering the target area according to the current scanning parameters in the current scanning cycle. Here, continuous means that each layer in a set of magnetic resonance images is continuously adjacent, and there is no "missing area" between layers.

[0068] Rapid magnetic resonance imaging refers to an imaging method that can shorten the magnetic resonance imaging time. For example, magnetic resonance scanning methods that adopt means such as shortening the repetition time TR, acquiring fewer phase encoding lines, using parallel acquisition technology, using echo planar imaging sequence, using gradient echo imaging sequence, using EPI, PRESTO, b-SSFP imaging sequence, etc. Rapid magnetic resonance imaging can obtain magnetic resonance image data with higher resolution and more layers, which is convenient for establishing a three-dimensional temperature map. While meeting the real-time requirements of intraoperative magnetic resonance temperature monitoring, it can also contain more temperature data. For example, in the prior art, magnetic resonance images of 3 parallel tomographies are acquired in each cycle, and the data resolution of each layer (i.e., the slice thickness of each layer) is 3 mm, and the acquisition time of each cycle of data is about 4 s. In an embodiment of the present invention, rapid magnetic resonance sequence scanning is used, 20 continuous magnetic resonance images are acquired in each cycle, the data resolution of each layer is 1 mm, and the acquisition time of each cycle of data is 5 - 6 s. The data resolution is higher and still can meet the real-time requirements. More specifically, the rapid magnetic resonance imaging in the present invention refers to a magnetic resonance imaging method with an imaging cycle less than 6 s.

[0069] S12. For each set of continuous magnetic resonance images, a three-dimensional temperature map is established according to the phase map in the magnetic resonance images, and a three-dimensional amplitude map is established according to the amplitude map in the magnetic resonance images;

[0070] A three-dimensional temperature map is established based on magnetic resonance images of consecutive thin slices obtained from a fast magnetic resonance scan, which can improve the signal-to-noise ratio of the images, facilitate the observation of temperature conditions in three-dimensional space, and better guide the ablation process and evaluate the ablation status. Specifically, each magnetic resonance image includes a magnitude map and a phase map. Among them, the phase map can be used to generate a two-dimensional temperature map at the corresponding acquisition position (slice). The phase maps in a set of magnetic resonance images can be used to establish the three-dimensional temperature map corresponding to this period. The magnitude map characterizes the structural information at the corresponding acquisition position (slice). The three-dimensional magnitude map of the current period is reconstructed based on each magnitude map. The three-dimensional magnitude map is convenient for observing structural information from multiple angles in space, determining whether the current magnetic resonance scan range covers the target area, and determining the ablation status of the target area, etc.

[0071] S13. Generate new scan parameters for the fast magnetic resonance imaging in the next period according to the registration relationship between the three-dimensional magnitude maps of the current period and the reference period.

[0072] It can be understood that, under the condition that the scan parameters remain unchanged, the scan range of the magnetic resonance device in the real space within one period is certain. When the patient moves, the range of the patient's body part scanned by the magnetic resonance device changes. It is possible that the target area cannot be scanned, or the imaging field of view changes, affecting the observation effect.

[0073] Therefore, the three-dimensional magnitude map of the current period is registered with the three-dimensional magnitude map of the reference period. If they can be directly matched without conversion, it means that the patient has not moved, and the current scan parameters (i.e., the correction amplitude is 0) can be maintained for the magnetic resonance imaging in the next period. If conversion is required to match, it means that the patient has moved. At this time, the overlapping part area after matching is the range of the body part scanned by the magnetic resonance device both before and after the movement, and the obtained registration relationship corresponds to the "movement parameters" of the patient. Based on this registration relationship, the current scan parameters can be calibrated and updated. After correcting the current scan parameters, new scan parameters can be obtained. The host sends the new scan parameters to the magnetic resonance device so that the magnetic resonance device can perform magnetic resonance scanning in the next scan period according to the new scan parameters (i.e., the "current scan parameters" of the next period), making the target area appear at a suitable position within the magnetic resonance scan range (for example, making the target area located at the center of the scan range), which is convenient for monitoring the status of the target area.

[0074] It can be understood that in the prior art, the heating effect of the optical fiber can only be monitored in several isolated two-dimensional cross-sections perpendicular to the optical fiber direction. As long as the patient moves, it is necessary to re-perform the positioning sequence scan, re-determine the scan parameters, and obtain the two-dimensional magnetic resonance images at the cross-sections perpendicular to the optical fiber direction. Since the present invention acquires and reconstructs the three-dimensional temperature map, the temperature data can be observed from any angle, direction, and cross-section. When the patient moves, the magnetic resonance scanning range can be corrected conveniently and quickly according to the registration relationship of the three-dimensional amplitude maps of each phase, without performing the positioning sequence scan and without interrupting the normal laser ablation process.

[0075] In this embodiment, through fast magnetic resonance imaging, more data is acquired while meeting the real-time requirement of temperature monitoring. The three-dimensional temperature map is reconstructed based on the phase maps in each group of consecutive magnetic resonance images, providing more comprehensive information guidance for the laser ablation process. The three-dimensional amplitude map is reconstructed based on the amplitude maps in each group of magnetic resonance images, facilitating the observation of the three-dimensional structure. At the same time, according to the registration relationship between the current three-dimensional amplitude map and the previous one, the current scan parameters are corrected efficiently and accurately, avoiding the situation of poor image quality caused by patient movement and the need to re-perform the positioning sequence scan, which is beneficial to improving the surgical efficiency of laser interstitial thermotherapy.

[0076] Furthermore, the three-dimensional temperature map and the three-dimensional amplitude map can be fused and displayed, or the three-dimensional temperature map and the preoperative three-dimensional image can be fused and displayed, facilitating the user to intuitively observe the temperature status at each position.

[0077] Based on any one of the embodiments, in one embodiment, before S11, it further includes:

[0078] Obtain the positioning sequence scan image, establish a positioning three-dimensional structure diagram according to the positioning sequence scan image, and register the positioning three-dimensional structure diagram with the preoperative three-dimensional image to determine the position of the target area; wherein, the target area is outlined or automatically segmented in the preoperative three-dimensional image;

[0079] Determine the initial scan parameters according to the position of the target area, or determine the scan parameters according to the user input instruction.

[0080] Specifically, the position of the target area is determined by a positioning sequence scan, which can be a T1WI (T1-weighted imaging), T2WI (T2-weighted imaging), DWI (diffusion-weighted imaging), SE (spin echo sequence imaging) scan, etc. Preferably, the imaging method of the positioning sequence scan image is consistent with that of the preoperative three-dimensional image to improve the registration accuracy between the positioning sequence scan image and the preoperative three-dimensional image. The positioning sequence scan image contains a series of amplitude maps, and a three-dimensional structure diagram (i.e., the positioning three-dimensional structure diagram) for positioning the target area can be reconstructed based on this series of amplitude maps. The target area (the human body part to be subjected to the ablation operation, such as the liver, spleen, prostate, head, etc.) can be observed in the positioning three-dimensional structure diagram.

[0081] Since medical image acquisition has been performed preoperatively, a preoperative three-dimensional image has been established, and the target area has been outlined and determined from the preoperative three-dimensional image, or the target area has been automatically semantically segmented from the preoperative three-dimensional image by a semantic segmentation model. On this basis, by registering the positioning sequence scan image with the preoperative three-dimensional image, the position of the target area in the positioning sequence scan image can be correspondingly determined; of course, the target area position therein can also be directly outlined or automatically semantically segmented based on the positioning sequence scan image.

[0082] According to the position of the target area, initial scan parameters (for intraoperative rapid magnetic resonance imaging in the first stage) can be determined, such as the scan direction, the number of scan layers, the scan position, the scan resolution, etc. Among them, the scan direction is the direction of the tomogram, the number of scan layers is the number of magnetic resonance images acquired in each scan cycle to cover the target area (such as 10 layers, 15 layers, 18 layers, etc.), the scan position is the acquisition position of the multi-layer magnetic resonance images, and the scan resolution is the slice thickness of each layer of magnetic resonance images (such as 1 mm, 2 mm, 3 mm, etc.). The initial scan parameters can be automatically set by an application program. For example, the number of scan layers can be automatically set according to the size of the target area and the scan resolution; some parameters can also be randomly set (for example, the scan direction can be randomly set. Since the three-dimensional temperature map and the three-dimensional amplitude map are reconstructed, the user can view the temperature and structural data from any cross-section, and the magnetic resonance scan direction does not have to be perpendicular to the fiber direction); the initial scan parameters can also be determined according to the user's input instructions. For example, the user selects a scan direction that is convenient for observing a certain specific structure according to the organizational structure to be observed. Further, a certain margin of the number of scan layers can be set so that the magnetic resonance scan range encompasses the target area, facilitating the monitoring of the current ablation boundary and determining whether the normal tissue around the target area is mistakenly ablated.

[0083] In this embodiment, a three-dimensional structure diagram for positioning is reconstructed by scanning the positioning sequence and registered with the preoperative three-dimensional image, accurately determining the position of the target area. On this basis, the initial scanning parameters are reasonably set, laying a foundation for intraoperative rapid magnetic resonance imaging and improving the quality of the three-dimensional temperature map.

[0084] Based on any of the embodiments, in one embodiment, before S11, it further includes:

[0085] Obtain the positioning sequence scanning image, establish a positioning three-dimensional structure diagram according to the positioning sequence scanning image, and display the positioning three-dimensional structure diagram through a display device;

[0086] Determine the position of the target area and the initial scanning parameters according to the user input instruction.

[0087] Specifically, the position of the target area is determined by the positioning sequence scanning. The positioning sequence scanning can be T1WI (T1-weighted imaging), T2WI (T2-weighted imaging), DWI (diffusion-weighted imaging), SE (spin echo sequence imaging) scanning, etc. The positioning sequence scanning image contains a series of amplitude maps. According to this series of amplitude maps, a three-dimensional structure diagram (i.e., the positioning three-dimensional structure diagram) for positioning the target area can be reconstructed, and the positioning three-dimensional structure diagram is displayed on the display device to facilitate the user to observe and determine the position of the target area and input the initial scanning parameters.

[0088] Based on the above embodiments, in one embodiment, determining the initial scanning parameters according to the position of the target area includes:

[0089] According to the shape of the target area, take the direction of the thinnest sandwich as the initial scanning direction; wherein, the thinnest sandwich refers to two parallel planes that sandwich the target area range so that the plane spacing is the smallest.

[0090] Specifically, the position of the target area represents the actual space occupied by the target area, that is, the position of the target area contains the shape information of the target area. Clamp the target area with two parallel planes. When the spacing between the two parallel planes is the smallest, it constitutes the "thinnest sandwich". Taking the direction of the thinnest sandwich as the scanning direction makes the overall scanning layer thickness of the intraoperative magnetic resonance scanning the smallest and the number of scanning layers the least. Correspondingly, the magnetic resonance scanning cycle can be shortened and the update frequency of the three-dimensional temperature map can be increased.

[0091] In this embodiment, combined with the scenario of laser interstitial thermotherapy, according to the shape of the target area, taking the direction of the thinnest sandwich as the scanning direction, the magnetic resonance scanning parameters are optimized, and the acquisition rate of the magnetic resonance image and the update frequency of the three-dimensional temperature map are improved.

[0092] Based on any of the embodiments, in one embodiment, the positioning sequence scanning image is an image obtained based on T1WI.

[0093] The localization sequence scan can be based on T1WI imaging. T1 refers to the spin-lattice relaxation time (also known as the longitudinal relaxation time). T1WI, i.e., T1-weighted imaging, emphasizes the longitudinal relaxation differences of tissues while minimizing the influence of other characteristics such as transverse relaxation on the image. Since within a certain temperature range, the TI value has a linear relationship with temperature, acquiring T1WI of the target area can not only localize the target area but also measure the initial temperature of the target area accordingly.

[0094] In addition, the imaging methods such as T2WI imaging, DWI imaging, and SE imaging can also be used for the localization sequence scan images. T2 is the transverse duration, T2WI refers to highlighting the transverse relaxation differences of tissues during imaging, DWI imaging refers to diffusion-weighted imaging, and SE imaging refers to spin-echo sequence imaging.

[0095] In this embodiment, through the localization sequence scan based on T1WI, the target area is accurately located, which is convenient for determining the initial scan parameters and providing guidance for the ablation of the target area.

[0096] Based on any one of the embodiments, in one embodiment, the fast magnetic resonance sequence scan image is an image obtained by scanning based on the gradient echo sequence.

[0097] Specifically, the purpose of using the fast magnetic resonance sequence is to quickly acquire multi-layer magnetic resonance images to generate a three-dimensional temperature map with a resolution that meets the requirements under the condition of meeting the real-time demand for temperature monitoring. The gradient echo sequence scan (FFE) has a higher imaging efficiency than the spin echo sequence scan. The spin echo tissue has a longer spontaneous relaxation time, and its TE (echo time) is longer, such as 10 - 15 ms, while the echo time of the gradient echo can be as short as 2 ms.

[0098] In addition, fast magnetic resonance scanning can also be achieved by shortening the repetition time TR, acquiring fewer phase-encoding lines, using parallel acquisition technology, using gradient echo imaging, using EPI (echo planar imaging), PRESTO (gradient echo translational imaging), and b-SSFP (balanced steady-state free precession imaging) sequences. The following is a brief description of these fast magnetic resonance scanning methods:

[0099] Parallel acquisition technology: The parallel acquisition technology uses a multi-channel phased array coil to reduce the acquisition density of the limited encoding lines in the K space, accelerate the acquisition speed of magnetic resonance images, can shorten the image acquisition time by 1 - 16 times, increase the spatial resolution or increase the three-dimensional acquisition imaging range on the premise of unchanged acquisition time, and can also increase the number of repeated acquisitions to improve the image quality and reduce artifacts.

[0100] EPI (Echo Planar Imaging): ERI is a special form of gradient echo. It uses rapid reverse gradients to generate a series of gradient echoes within a single relaxation time, and phase encodes them separately, filling them into the corresponding K-space to achieve cross-sectional imaging.

[0101] PRESTO (Progressive RElocution with Steady-state Optimization): An additional negative gradient pulse is added to the slice-selective gradient of the gradient pulse sequence. A positive gradient pulse with an equal area is given before the next excitation pulse. Then, the gradient echo will be generated within the next TR time, which is equivalent to shifting the echo generated within the current TR time to the next TR time. This technique corrects the gradient echo shift, and the sequence is called the PRESTO sequence.

[0102] b-SSFP (Balanced Steady-State Free Precession): When both the longitudinal magnetization vector and the transverse magnetization vector reach a steady state, this situation is called steady-state free precession. When reasonable TR, TE, and flip angles are set such that all kinds of echoes (FID, SE, and STE) generated by multiple radiofrequency pulses are just fused into one echo, reaching a balanced state, this gradient echo sequence is called the balanced steady-state free precession sequence (b-SSFP). The signal collected by b-SSFP is the fused signal of various echoes, and its information density is higher.

[0103] It should be noted that fast magnetic resonance imaging can obtain magnetic resonance images with higher resolution and more layers, which is convenient for subsequent establishment of temperature maps. When meeting the clinical requirements of intraoperative magnetic resonance temperature monitoring, it can also contain more temperature data. For example, currently, 3 layers of magnetic resonance images are acquired per cycle, and the data resolution of each layer (i.e., the slice thickness of each layer) is 3 mm, and the acquisition time of each cycle of data is about 4 - 6 s. If fast magnetic resonance imaging is used, 20 layers of magnetic resonance images can be obtained per cycle, the data resolution of each layer is 1 mm, and the acquisition time of each cycle of data is 3 - 6 s. The data resolution is higher and still meets the real-time requirements.

[0104] In this embodiment, through the above specific fast magnetic resonance imaging method, magnetic resonance images are acquired quickly and with high quality, which are used to reconstruct a high-resolution three-dimensional temperature map, providing sufficient information support for the laser ablation process.

[0105] Based on any embodiment, in one embodiment, S11 includes:

[0106] Determine the target area to be sampled in the current cycle according to the preset magnetic resonance downsampling rule;

[0107] Perform magnetic resonance scanning on the target area to obtain the magnetic resonance image of the target area;

[0108] Based on the magnetic resonance image of the target area, continuous magnetic resonance images of the current cycle are obtained.

[0109] Specifically, during the intraoperative ablation process, the magnetic resonance device needs to image the target area to be ablated and the tissues nearby to monitor the temperature status. That is, the "continuous magnetic resonance images obtained per cycle" need to cover the target area. To achieve fast magnetic resonance imaging, when collecting magnetic resonance images in a specific cycle, only a part of the area that "covers the target area" is imaged, and then the "continuous magnetic resonance images" covering the target area are repaired by the method of "supplementary data". The magnetic resonance downsampling rule is a rule preset for determining the target area to be scanned in the current cycle. For example: To completely cover the target area, n layers of magnetic resonance images need to be collected. The preset magnetic resonance downsampling rule is the scanning strategy (i.e., interlayer downsampling) for which layers to scan and which layers not to scan in the current cycle. More specifically, for example, odd-numbered layers are collected in one cycle, and even-numbered layers are collected in the next cycle, and so on; or for example, 3i + 1 layers (i = 0, 1, 2, 3...) are collected in one cycle, 3i + 2 layers (i = 0, 1, 2, 3...) are collected in the next cycle, and 3i + 3 layers (i = 0, 1, 2, 3...) are collected in the next cycle, and so on; or for example, the preset magnetic resonance downsampling rule can also be judged in combination with the number of layers to be sampled. When the number of layers exceeds the layer number threshold, the first strategy is adopted, and when the number of layers does not exceed the layer number threshold, the second strategy is adopted.

[0110] Among them, the layer number threshold can be a preset value used to judge whether the number of layers to be scanned in the target area is too large, so as to adopt different interlayer downsampling strategies, such as the layer number threshold being 10, 15, 18, etc. The first strategy is a downsampling strategy set for the case where the number of layers to be sampled is too large, and the second strategy is a downsampling strategy set for the case where the number of layers to be sampled is small. Therefore, the layer interval of the first strategy is greater than that of the second strategy. For example, when the number of layers exceeds 12, it is divided into an odd-numbered layer collection cycle and an even-numbered layer collection cycle. When the number of layers does not exceed 12, sampling is performed on each layer within one cycle.

[0111] It should be noted that since the scanned target area remains unchanged, there will be the same spatial redundant information between frames. The accelerated acquisition method of interlayer downsampling can be used to accelerate the acquisition of magnetic resonance images. For example, using the EPI or GRE sequence, the accelerated acquisition method using interlayer downsampling can improve the image acquisition speed. In this way, only some layers of the target area are scanned within each cycle to accelerate the acquisition of magnetic resonance images, and then the collected data of the current cycle and the previous cycle can be used to reconstruct a complete image, so as to ensure the quality of the collected image and achieve high spatio-temporal resolution and large-range temperature imaging without changing the image quality and scanning time.

[0112] In an alternative implementation of this embodiment, the preset magnetic resonance downsampling rule is to sample in odd layers and even layers in cycles; according to the preset magnetic resonance downsampling rule, determining the target area to be sampled in the current cycle includes:

[0113] Determine the sampling layer scanned in the previous cycle;

[0114] When the sampling layer in the previous cycle is an odd layer, determine that the target layer to be sampled in the current cycle is an even layer;

[0115] When the sampling layer in the previous cycle is an even layer, determine that the target layer to be sampled in the current cycle is an odd layer.

[0116] That is to say, the sampling layers in two adjacent cycles are different. In practical applications, the sampling layer scanned in the previous cycle can be determined first. If the sampling layer scanned in the previous cycle is an odd layer, then the even layers are sampled in the current cycle. If the sampling layer scanned in the previous cycle is an even layer, then the odd layers are sampled in the current cycle. For example, the continuous magnetic resonance images covering the target area include 1 - 10 layers. One cycle scans layers 1 / 3 / 5 / 7 / 9, and the next cycle samples layers 2 / 4 / 6 / 8 / 10.

[0117] In this embodiment, the area to be sampled is sampled in odd layers and even layers. One cycle samples odd layers, and the other cycle samples even layers. Only some layers of the target area are scanned in each cycle, and the sampling layers of two adjacent areas do not repeat, achieving maximum downsampling, thereby improving the acquisition speed of the magnetic resonance image sequence to meet the clinical requirements for magnetic resonance - based temperature measurement and ablation calculation.

[0118] In an alternative implementation of this embodiment, the preset magnetic resonance downsampling rule is to adopt the first strategy when the number of layers to be sampled exceeds the layer threshold, and adopt the second strategy when it does not exceed the layer threshold; according to the set inter - layer downsampling rule, determining the target layer to be sampled in the current cycle includes:

[0119] Obtain the number of layers to be sampled in the continuous magnetic resonance images;

[0120] When the number of layers to be sampled exceeds the layer threshold, determine the target layer to be sampled in the current cycle according to the first strategy;

[0121] When the number of layers to be sampled does not exceed the layer threshold, determine the target layer to be sampled in the current cycle according to the second strategy.

[0122] Specifically, the layer threshold can be a preset value, which is used to determine whether the number of layers to be scanned in the target area is too large, so as to adopt different inter-layer downsampling strategies. For example, the layer thresholds are 10, 15, 18, etc. The first strategy is a downsampling strategy set for the case where the number of layers to be sampled is too large, and the second strategy is a downsampling strategy set for the case where the number of layers to be sampled is small. Therefore, the layer interval of the first strategy is greater than that of the second strategy. That is, due to the excessive number of layers to be sampled in the target area, the first strategy ignores more layers within a period and does not sample them to ensure the scanning speed. For example, the first strategy can sample every k - 1 layers in different periods. That is, in the first period, the first layer is sampled, in the next period, the (1 + k)th layer is sampled, and in the next period, the (1 + 2k)th layer is sampled, and so on. The second strategy can sample every m - 1 layers in different periods, where m is less than k.

[0123] In specific implementation, the first strategy or the second strategy can be configured based on actual requirements. The first strategy or the second strategy can also sample odd layers and even layers respectively at the above-mentioned interval periods.

[0124] Exemplarily, assume that the target area includes 1 - 12 layers to be sampled, and the layer threshold is 10. At this time, the number of layers to be sampled in the target area exceeds the layer threshold. In one period, layers 1 / 4 / 7 / 10 are scanned, in the second period, layers 2 / 5 / 8 / 11 are sampled, and in the third period, layers 3 / 6 / 9 / 12 are collected. Additionally, assume that the layer threshold is 15. At this time, the number of layers to be sampled in the target area does not exceed the layer threshold. At this time, layers 1 / 3 / 5 / 7 / 9 / 11 can be collected in one period, and layers 2 / 4 / 6 / 8 / 10 / 12 can be collected in the next period. That is to say, when the number of layers to be sampled in the target area exceeds the layer threshold, sampling is performed every 2 layers in each period; when the number of layers to be sampled in the target area does not exceed the layer threshold, sampling is performed every 1 layer in each period.

[0125] It should be noted that when the number of layers to be sampled exceeds the layer threshold, it indicates that the number of layers to be sampled in the target area is relatively large. At this time, the first strategy can be used to determine the target layer to be sampled in the current period. When the number of layers to be sampled does not exceed the layer threshold, it indicates that the number of layers to be sampled in the target area is relatively small, and the second strategy is used to determine the target layer to be sampled in the current period. For different situations of the target area, different inter-layer downsampling strategies can be adopted respectively, which can adapt to more application scenarios and improve applicability and flexibility.

[0126] In an optional implementation manner of this embodiment, in addition to using the inter-layer downsampling method to improve the scanning speed, the intra-layer downsampling method can also be used to further improve the scanning speed to meet the requirements of temperature monitoring. Fast magnetic resonance imaging scans by columns. According to the preset magnetic resonance downsampling rule, the target area to be sampled in the current period is determined, including:

[0127] Determine the data columns to be sampled in the current cycle according to the preset in-layer downsampling rule;

[0128] Perform magnetic resonance scanning on the data columns to be sampled to obtain a magnetic resonance image sequence of the target area.

[0129] It should be noted that the magnetic resonance rapid imaging sequence scans by columns. For example, GRE. That is, when the magnetic resonance rapid imaging sequence scans a certain layer, it does not scan the entire layer at once, but scans a column of data in a layer at a time. For the magnetic resonance rapid imaging sequence that scans by columns, in addition to the above-mentioned inter-layer downsampling, in-layer downsampling can also be used, and only some columns in a layer are collected in one scan to improve the scanning speed. Additionally, it should be noted that if the magnetic resonance rapid imaging sequence scans by layer, such as EPI, when scanning a certain layer, it scans the entire layer at once, and in-layer downsampling cannot be performed, only inter-layer downsampling can be performed.

[0130] Specifically, the set in-layer downsampling rule is a pre-set data column selection strategy for the in-layer data columns, that is, for a certain layer, which data columns to collect and which data columns not to collect. For example, the set in-layer downsampling rule can be to collect the 2n-th column data in the current cycle, the (2n + 1)-th column data in the next cycle, the (2n + 2)-th column data in the next cycle, and so on; or, use the method of 3n, 3n + 1, 3n + 2 to increase the in-layer data collection speed by 2 times or 3 times.

[0131] In practical applications, the set inter-layer downsampling rule is to select some column data from the column data of each layer for collection. According to the set in-layer downsampling rule, it can be determined which data columns to be collected in the current cycle, and then the magnetic resonance rapid imaging sequence is used to scan the data columns to be collected in the target layer to obtain the magnetic resonance image of the current cycle. In this way, for the target layer, only some data columns need to be collected, greatly improving the in-layer data collection speed.

[0132] It should be noted that for the target area (i.e., the ablation area), due to the continuity of temperature in physical space and time, the temperature information of adjacent positions can be used to estimate the temperature of the unsampled part, so as to ensure the temperature imaging quality of the target area.

[0133] In specific implementation, the test area can be fully sampled in advance based on the temperature measurement optical fiber, the complete image can be obtained through testing, and the downsampled image can be obtained by downsampling the test area. Then, the complete image obtained through testing is used as the label, and the downsampled image is used as the input of the deep learning model to train the deep learning model to obtain a deep learning model capable of reconstructing the complete image. Subsequently, the data sequence collected by downsampling is input into the trained deep learning model, and the reconstructed complete image sequence can be obtained.

[0134] In the embodiments of the present specification, an accelerated acquisition method of inter-layer downsampling and intra-layer downsampling can be adopted. Only partial layers of the target region and partial data columns in these partial layers are scanned in each period to accelerate the acquisition of magnetic resonance images, and then a complete image is reconstructed based on the acquired data. When reconstructing the image, a reconstruction algorithm (such as interpolation method) is used to utilize the invariance of the spatial information of the target region and the continuity of temperature in the physical space and time to reconstruct the complete image information, so as to ensure the quality of the acquired image and achieve high spatio-temporal resolution and large-range temperature imaging without changing the image quality and scanning time.

[0135] It should be noted that in actual application scenarios, the methods of inter-layer downsampling and intra-layer downsampling can be used simultaneously to accelerate the acquisition of magnetic resonance images, or the method of inter-layer downsampling or intra-layer downsampling can be used alone to accelerate the acquisition of magnetic resonance images. The embodiments of the present specification do not limit this. For example, the layers to be sampled in the target region can be determined, and each layer to be sampled is used as the layer to be scanned in the current period. Then, for each layer, based on the intra-layer downsampling rule, it is determined which data columns are to be acquired.

[0136] Based on any one of the embodiments, in one embodiment, according to the magnetic resonance image of the target region, a continuous magnetic resonance image of the current period is obtained, including:

[0137] According to the magnetic resonance image of the target region, a continuous magnetic resonance image covering the target area is obtained by interpolation; or,

[0138] According to the magnetic resonance image of the target region and combined with the magnetic resonance image of its complementary period, a continuous magnetic resonance image covering the target area is obtained.

[0139] Specifically, for example, the preset magnetic resonance downsampling rule is to sample in odd layers and even layers. One layer, three layers, five layers, seven layers, or nine layers are collected in one period, and two layers, four layers, six layers, eight layers, or ten layers are collected in the next period, and so on in a cycle. In the T n period, the magnetic resonance data of layers 1, 3, 5, 7, and 9 are collected, and the data of layers 2, 4, 6, 8, and 10 are missing. The magnetic resonance images of the even layers can be directly obtained by interpolation according to the magnetic resonance images of the odd layers. For example, according to the magnetic resonance images of the first layer and the third layer, the magnetic resonance image of the second layer is filled in, and according to the magnetic resonance images of the third layer and the fifth layer, the magnetic resonance image of the fourth layer is filled in until a continuous magnetic resonance image of ten layers is obtained. Or, the missing data can also be filled in according to the complementary period. For example, on the basis of the magnetic resonance data of layers 1, 3, 5, 7, and 9 collected in the T n period, the magnetic resonance data of the even layers collected in the T n-1 period are also combined to fill in the T nEven-layer data with missing periods, or combined with T n-3 , T n-5 and other complementary periodic-acquired even-layer magnetic resonance data to fill in the T n even-layer data with missing periods. The data accuracy supplemented directly through the interpolation step is limited. Generally, the structure / temperature state of the patient's target area does not change suddenly. Therefore, the data in the complementary period of the current period can be used to provide a reference for the "interpolation process" of the current period, further improving the repair accuracy. It can be understood that the above only exemplifies the "repair" process in the case of interlayer downsampling with one layer interval. In the case of more layer intervals, the missing layers can also be filled in by linear interpolation (or further combined with the complementary period). In the case of intralayer downsampling, the missing data can also be repaired by referring to the above method.

[0140] In this embodiment, a continuous magnetic resonance image is obtained by interpolation based on the downsampled magnetic resonance image, which improves the efficiency of collecting magnetic resonance images, meets the requirement of real-time monitoring of temperature during the laser ablation process, and further combines complementary periods to fill in the missing magnetic resonance data, improving the accuracy of the obtained continuous magnetic resonance image.

[0141] Based on any embodiment, in one embodiment, S11 includes:

[0142] Periodically scan the target area through a magnetic resonance fast imaging sequence;

[0143] Use the reference period to correct the magnetic resonance image of the current period to obtain a corrected magnetic resonance image.

[0144] Specifically, the magnetic resonance fast imaging sequence can be echo planar imaging (EPI), and the obtained magnetic resonance image is the EPI sequence. Among them, EPI is one of the fastest magnetic resonance imaging methods so far. It is a special form of gradient echo. It uses a fast reverse gradient to generate a series of gradient echoes within a single relaxation time (TR) and phase-encode them respectively, filling them into the corresponding k-space to achieve sectional imaging.

[0145] The magnetic resonance fast imaging sequence can also be obtained by scanning the target area based on other fast scanning algorithms, such as shortening the repetition time TR, collecting fewer phase-encoding lines, parallel acquisition technology, gradient echo magnetic resonance pulse sequence (GRE), gradient echo translation imaging (PRESTO), balanced steady-state free precession imaging (B-SSFP), etc.

[0146] Magnetic resonance rapid imaging sequences can often complete the acquisition of an image in a few milliseconds. However, information may be lost during the rapid acquisition process, resulting in distortion of the acquired image, and further leading to inaccurate temperature maps constructed subsequently, affecting the operation. Taking the EPI (echo planar imaging) as an example of magnetic resonance rapid imaging sequences, EPI can complete the acquisition of an image in a few milliseconds. Therefore, this technology is one of the rapid signal acquisition methods, and rapid scanning of 10 - 20 layers of images (1 - 4 s) can be achieved through the fast EPI sequence. However, since the EPI sequence generates signals through continuous alternating changes in gradients and there is no refocusing pulse to correct the inhomogeneity of the main magnetic field and the error of phase information, as the EPI factor increases, the accumulated phase error becomes larger and larger, and the related deformation and artifacts of the image will also become heavier and heavier.

[0147] In practical applications, since the position of the patient or the phantom remains unchanged during the scanning of the target area by the magnetic resonance rapid imaging sequence, the tissue spatial information in the same scanning plane remains unchanged, such as blood vessels, tumor boundaries, cerebral sulci, etc. That is, the spatial distribution of the target area is basically unchanged. Therefore, the present invention uses the invariant spatial position information to correct the distortion generated during the rapid scanning process, thereby achieving the acquisition of a rapid 3D temperature sequence without reducing the spatial resolution. Specifically, the reference period without spatial distortion (or that has completed distortion correction) can be used to correct the obtained magnetic resonance image sequence of the current period to obtain the corrected magnetic resonance image of the current period, thus realizing efficient and accurate three-dimensional temperature detection.

[0148] Based on the previous embodiment, in one embodiment, the reference period is the positioning sequence scan image obtained by pre-scanning the reference area, and the reference area covers the target area.

[0149] Specifically, the positioning sequence scan can be T1WI (T1-weighted imaging), T2WI (T2-weighted imaging), DWI (diffusion-weighted imaging), SE (spin echo sequence imaging) scan, etc. The range of the positioning sequence scan is relatively large. For example, when laser ablation of an intracranial tumor is required, the head (reference area) of the patient is scanned by the positioning sequence. Based on the positioning sequence scan, the position of the tumor (target area) can be determined, which is convenient for rapid magnetic resonance imaging of a small area of the tumor (target area) through a magnetic resonance device during the laser ablation process, improving the real-time performance of temperature detection. It can be understood that the imaging range of the above positioning sequence scan image is relatively large and the imaging accuracy is high. In this embodiment, it is also used as the reference period to correct the magnetic resonance rapid sequence image acquired during the operation and repair the distortion therein. Specifically, correcting the magnetic resonance image of the current period using the reference period to obtain the corrected magnetic resonance image includes:

[0150] Obtaining the positioning sequence scan image obtained by pre-scanning;

[0151] Correct the magnetic resonance image of the current period according to the positioning sequence scan image to obtain the corrected magnetic resonance image.

[0152] In a possible implementation, the third position information of the target structure (such as blood vessels, tumor boundaries, cerebral sulci, etc.) in the magnetic resonance image of the current period can be determined first, and the fourth position information of the target structure in the positioning sequence scan image can be determined. Then, the spatial transformation matrix is calculated according to the third position information and the fourth position information, and the spatial transformation matrix is used as the distortion correction information to correct the magnetic resonance image sequence of the current period to obtain the corrected magnetic resonance image of the current period; in another implementation, the positioning sequence scan image and the magnetic resonance image sequence of the current period can be directly compared to correct the magnetic resonance image of the current period to obtain the corrected magnetic resonance image of the current period, and at the same time, the distortion correction information is output for storage for subsequent use.

[0153] In this embodiment, directly correcting the magnetic resonance image obtained in one period with the positioning sequence scan image can eliminate the distortion generated during the intraoperative magnetic resonance fast imaging sequence scan, ensure the accuracy of the magnetic resonance image, and thus ensure the accuracy of the subsequent constructed three-dimensional temperature map.

[0154] Based on any embodiment, in one embodiment, the reference period is any corrected period. Correcting the magnetic resonance image of the current period using the reference period includes:

[0155] Obtain the distortion correction information according to the first position of the target structure in the magnetic resonance image of the reference period and the second position of the target structure in the magnetic resonance image of the reference period; wherein, the reference period is the positioning sequence scan image obtained by pre-scanning the reference area, and the reference area covers the target area.

[0156] Correct the magnetic resonance image of the current period according to the distortion correction information.

[0157] Specifically, in this embodiment, the reference period is the period of the positioning sequence scan of the reference area, and the reference period is the corrected period. During the process of correcting the magnetic resonance image of the current period, first obtain the first position of the target structure (such as blood vessels, tumor boundaries, cerebral sulci, etc.) in the reference period and the second position of the target structure in the reference period, calculate the spatial transformation matrix according to the first position and the second position, and use this spatial transformation matrix as the distortion correction information to correct the magnetic resonance image sequence of the current period to obtain the corrected magnetic resonance image of the current period.

[0158] In this embodiment, the distortion correction is not directly performed according to the positioning sequence scan image, which reduces the difficulty of calculating the distortion correction information and improves the data processing efficiency.

[0159] Based on any embodiment, in one embodiment, the magnetic resonance image of the current period is corrected according to a reference period to obtain the corrected magnetic resonance image of the current period, including:

[0160] Obtain the distortion correction information of the previous period according to the reference period and the previous period of the current period;

[0161] Use the distortion correction information to correct the magnetic resonance image of the current period to obtain the corrected magnetic resonance image of the current period;

[0162] Based on the magnetic resonance image of the current period and the positioning sequence scan image, determine and store the distortion correction information of the current period, wherein the distortion correction information of the current period is used to correct the magnetic resonance image of the next period of the current period.

[0163] It should be noted that the distortion correction information of the previous period can be obtained first according to the reference period and the previous period of the current period, and then the magnetic resonance image of the current period can be directly corrected using the distortion correction information of the previous period to obtain the corrected magnetic resonance image of the current period, and then the distortion correction information of the current period can be determined for use in the next period of correction. That is to say, each period is corrected based on the distortion correction information of the previous period.

[0164] As an example, after the reference period, at the second period, since the previous period of the second period is the reference period, at this time, based on the positioning sequence image of the reference period and the magnetic resonance image of the second period, the magnetic resonance image of the second period can be corrected to obtain the corrected magnetic resonance image sequence of the second period, and at the same time, the distortion correction information of the second period is obtained and stored; thereafter, at the third period, the distortion correction information of the second period can be directly obtained to correct the magnetic resonance image of the third period to obtain the corrected magnetic resonance image sequence of the third period, and then based on the positioning sequence scan image of the reference period and the magnetic resonance image of the third period, the distortion correction information of the third period can be calculated and stored; thereafter, at the fourth period, the distortion correction information of the third period can be directly obtained to correct the magnetic resonance image of the fourth period,... and so on.

[0165] In this embodiment, each period is corrected based on the distortion correction information of the previous period, which can reduce the accumulation of distortion information in multiple periods and improve the accuracy of correction.

[0166] In an alternative implementation manner of this embodiment, determining and storing the distortion correction information of the current period according to the magnetic resonance image of the current period and the positioning sequence scan image includes:

[0167] Determine the fifth position information of the target structure in the magnetic resonance image of the current cycle;

[0168] Determine the sixth tissue position information of the target structure in the localization sequence scan image;

[0169] According to the fifth position information and the sixth position information, calculate the spatial transformation matrix, use the spatial transformation matrix as the distortion correction information, and store it.

[0170] Specifically, the target structure is a tissue with an unchanged position in the patient or phantom during the scanning process, such as blood vessels, tumor boundaries, cerebral sulci, etc.

[0171] It should be noted that the fifth position information of the target structure in the magnetic resonance image of the current cycle can be determined through image analysis, and the second tissue position information of the target structure in the localization sequence scan image can be determined. Then, according to the first tissue position information and the second tissue position information, calculate the spatial transformation matrix, and this spatial transformation matrix is the distortion correction information between the first tissue position information and the second tissue position information. In this way, by using the position information of the invariant target structure, the distortion correction information of the current cycle is determined and stored, and the distortion correction information of the current cycle can be directly obtained for correction in the next cycle.

[0172] In an optional implementation manner of this embodiment, in addition to the above method where the magnetic resonance images obtained in each cycle are directly corrected based on the localization sequence scan image scanned in the reference cycle, or each cycle is directly corrected based on the distortion correction information of the previous cycle, any cycle can be optionally selected as a constant reference cycle to correct the magnetic resonance images of each cycle. Specifically, correcting the magnetic resonance image of the current cycle according to the reference cycle to obtain the corrected magnetic resonance image of the current cycle includes:

[0173] Select any cycle as the constant reference cycle;

[0174] Obtain the constant distortion correction information according to the reference and the constant reference cycle;

[0175] Use the constant distortion correction information to correct the magnetic resonance image of the current cycle to obtain the corrected magnetic resonance image of the current cycle.

[0176] It should be noted that any cycle can be selected as the constant reference cycle, then the constant distortion correction information is obtained according to the reference cycle and the constant reference cycle, and then the obtained constant distortion correction information is used to correct the magnetic resonance image of the current cycle to obtain the corrected magnetic resonance image of the current cycle. That is to say, the magnetic resonance images of each cycle are corrected based on the constant distortion correction information, and the constant distortion correction information can be determined based on any selected cycle, and the correction method is more flexible and can adapt to different scenario requirements.

[0177] Among them, for the specific implementation process of obtaining the constant distortion correction information according to the reference period and the correction reference period, reference can be made to the above-mentioned specific implementation process of determining the distortion correction information of the current period based on the magnetic resonance image and the positioning sequence scan image of the current period, which will not be elaborated here.

[0178] In addition, during fast magnetic resonance imaging, if a fast magnetic resonance imaging sequence is used and the patient also has head movement, at this time, it is preferably to correct the magnetic resonance image of the current period according to the reference period to obtain a continuous corrected magnetic resonance image, so as to avoid the defect that the imaging regions of the current period and the reference period (non-reference period) are inconsistent and the correction error caused by the distortion of both is large. Or, directly register the distorted images collected in the reference period and the current period to obtain distortion correction information, and use this distortion correction information to correct the distortion correction information of the reference period, and then use it to correct the magnetic resonance image of the current period. Specifically, correcting the magnetic resonance image of the current period using the reference period includes:

[0179] Register the magnetic resonance image of the reference period and the magnetic resonance image of the current period to obtain distortion correction information;

[0180] According to the distortion correction information of the reference period and the distortion correction information, correct the magnetic resonance image of the current period to obtain a continuous magnetic resonance image of the current period.

[0181] The distortion correction information of the reference period can be obtained with reference to the foregoing embodiments. In this embodiment, the imaging distortion is successfully corrected in the case of imaging distortion in the fast magnetic resonance imaging sequence and head movement of the patient, the imaging quality is improved, and it is also convenient to obtain more accurate scanning parameters of the magnetic resonance device.

[0182] Based on any one of the embodiments, in one embodiment, after S12, the method further includes:

[0183] Compare the background region of the current period with that of the previous period;

[0184] If the change in the cumulative gray value of the background region does not exceed the preset threshold, then enter the next period and execute S11;

[0185] If the change in the cumulative gray value of the background region exceeds the preset threshold, jump to S13.

[0186] Specifically, the background area refers to the part of the target part (the human body to be subjected to ablation, such as the liver, spleen, prostate, head, etc.) that does not belong to the target area. The background area can be selected as the part of the target part that is outside the target area and has a certain distance margin from the target area to avoid the influence of optical fiber heating and heat conduction. The background area can also be preferably a skull area. The grayscale of the skull area in the magnetic resonance image will basically not change. Based on the skull judgment, it can be more accurately judged whether the patient has moved. The background area will not be heated during the laser ablation process, and the tissue structure will not change. The background area in the three-dimensional amplitude map of the current cycle is compared with the background area in the three-dimensional amplitude map of the previous cycle. If the difference in the cumulative grayscale value within the range of the background area of ​​the two is less than or equal to the preset threshold, it means that the patient has not moved, and the magnetic resonance scanning of the next cycle can be continued according to the current scanning parameters. If the difference is greater than the preset threshold, it means that the patient has moved, and it is necessary to execute S13 to correct the current scanning parameters and determine new scanning parameters for the next cycle of magnetic resonance scanning.

[0187] For example, the method for determining the above-mentioned background area is that for each period of the three-dimensional amplitude map, the background area of ​​the current period is re-determined based on the target area range. In this case, the determined background area is more accurate. Another example of determining the background area is that the background area of ​​the previous period is determined based on its relative area position in the three-dimensional amplitude map, and the background area is determined at the corresponding area position in the three-dimensional amplitude map of the current period. In this case, the process of determining the background area is simpler and faster, which facilitates the comparison of the three-dimensional amplitude maps of two periods. The present invention does not limit the method for determining the background area of ​​each period.

[0188] In this embodiment, through the above process, it is possible to quickly and accurately determine whether the patient has moved and whether the current scanning parameters need to be corrected, without having to perform a complex registration process in each cycle, thereby improving data processing efficiency.

[0189] Furthermore, in one embodiment, the reference cycle is a cycle before the current cycle. When correcting the scanning parameters, the current cycle is aligned with the reference cycle to obtain a alignment relationship. The scanning parameters of the reference cycle are corrected using this alignment relationship to obtain new scanning parameters for the next cycle of magnetic resonance scanning.

[0190] It can be understood that the reference period has less data (smaller volume), which reduces the amount of registration calculation. In addition, the registration of the current period with the reference period can also save the "rough registration" process, thereby improving the registration efficiency.

[0191] In another embodiment, the reference period is the period for performing a positioning sequence scan, which is a large-scale scan performed on the target site with a larger imaging range and higher imaging quality. The current period is directly registered with the positioning three-dimensional structure diagram of the positioning sequence scan period, and new scan parameters are directly determined according to the registration relationship, making the scan parameters more accurate and reasonable.

[0192] Based on any one of the embodiments, in one embodiment, S13 includes:

[0193] Register the current period with the background region of the three-dimensional amplitude diagram of the previous period. According to this registration relationship, correct the scan parameters on the basis of the scan parameters of the reference period to obtain new scan parameters.

[0194] Specifically, the implementation method of registering the current period with the three-dimensional amplitude diagram of the previous period is to determine the background region of the three-dimensional amplitude diagram of the previous period and the background region of the three-dimensional amplitude diagram of the current period, and then register the current period with the background region of the three-dimensional amplitude diagram of the previous period, and correct the current scan parameters according to the registration relationship of the background regions. The above-mentioned background region refers to the part of the target site that does not belong to the target area. The background region can be selected as the part of the target site that is outside the target area and has a certain distance margin from the target area to avoid the influence of optical fiber heating and heat conduction on the tissue structure and improve the registration accuracy.

[0195] In this embodiment, registration is only performed according to the background region, and according to this registration relationship, the current scan parameters are corrected, avoiding the reduction of registration accuracy caused by the change of the target area structure.

[0196] Based on any one of the embodiments, in one embodiment, after S12, the method further includes:

[0197] Judge the inclusion situation of the target area in the three-dimensional amplitude diagram of the current period;

[0198] When the three-dimensional amplitude diagram of the current period completely includes the target area, enter the next period and execute S11;

[0199] When the three-dimensional amplitude diagram of the current period partially includes the target area, jump to S13.

[0200] When the three-dimensional amplitude diagram of the current period completely does not include the target area, register the three-dimensional amplitude diagram of the current period with the positioning three-dimensional structure diagram, and determine new scan parameters according to this registration relationship; wherein, the positioning three-dimensional structure diagram is a three-dimensional amplitude diagram established according to the positioning sequence scan image.

[0201] Specifically, the situation of the target area in the three-dimensional amplitude map of the current cycle is judged. For example, the three-dimensional amplitude map is input into a deep learning model to segment the target area. Another example is that the three-dimensional amplitude map is input into a threshold segmentation model, and the target area is segmented according to the specific gray range based on the target area.

[0202] If the three-dimensional amplitude map of the current cycle completely contains the target area, it means that the intraoperative fast magnetic resonance imaging range at this time can still cover the target area. After reconstructing the three-dimensional temperature map and the three-dimensional structure map, the state of the target area can still be viewed in three-dimensional space. At this time, the magnetic resonance scan of the next cycle can be continued without calibrating the current scan parameters. Compared with the "patient movement correction" based on two-dimensional magnetic resonance images in the prior art, in the case of a small degree of patient movement, the present invention can still maintain the scan, does not affect the monitoring effect, and does not need to interrupt the laser ablation process.

[0203] If the three-dimensional amplitude of the current cycle partially contains the target area, it means that the current magnetic resonance scan range cannot cover the target area, and it is necessary to execute step S13 to correct the current scan parameters.

[0204] If the three-dimensional amplitude map of the current cycle does not contain the target area at all, it means that the degree of patient movement is large, and the three-dimensional amplitude map of the current cycle cannot be registered with the three-dimensional amplitude map of the previous cycle (or the registration accuracy is low). At this time, the patient movement parameters cannot be accurately determined based on the registration relationship between the three-dimensional amplitude maps of the current cycle and the previous cycle. Since a large-scale localization sequence scan has been performed on the target area before the intraoperative fast magnetic resonance, and a localization three-dimensional structure map has been established based on the localization sequence scan images, by registering the three-dimensional amplitude map of the current period with the localization three-dimensional structure map, the initial scan parameters are calibrated based on this registration relationship, and the new scan parameters can be accurately determined for the magnetic resonance scan of the next cycle.

[0205] Based on any one of the embodiments, in one embodiment, S13 includes:

[0206] In the three-dimensional amplitude of the current cycle, when the images at some tomographic positions match the previous cycle, and the images at the remaining tomographic positions do not match the previous cycle, the magnetic resonance images of the current cycle are not used for registration. The three-dimensional amplitude maps of the next cycle and the previous cycle are registered, and based on this registration relationship, corrections are made on the basis of the scan parameters of the previous cycle to obtain new scan parameters.

[0207] Specifically, referring to Figure 2 As shown, the upper figure shows the state of the three-dimensional amplitude map of the previous period, the middle figure schematically shows the state of the three-dimensional amplitude map generated in the current cycle. During the acquisition process of the magnetic resonance images of the current cycle, the patient moved. Since the patient movement occurred in a short period of time, and the acquisition of a group of magnetic resonance images requires a certain amount of time, the three-dimensional amplitude map of the current cycle may be asFigure 2 Parts A and B. In the figure, part A directly corresponds to a partial area at the same position in the previous cycle. Part A corresponds to the state of the patient before movement. Part B cannot directly correspond to the same position in the previous period. After registration, some areas can overlap. Part B corresponds to the state of the patient after movement. The following figure is a three-dimensional amplitude map generated by acquisition in the next cycle. In this case, the three-dimensional amplitude map of the current cycle cannot be directly registered with the three-dimensional amplitude map of the previous cycle (or the registration accuracy of direct registration is poor), and the three-dimensional amplitude map of the current cycle itself may also have poor quality (artifacts). At this time, the magnetic resonance image of the current period is not used for registration (that is, the scanning parameters are not corrected in the current cycle). In the next cycle, the three-dimensional amplitude map of the next cycle is registered with the three-dimensional amplitude map of the previous cycle (here, the previous cycle and the next cycle are both relative to the "current cycle" corresponding to the patient's movement process). According to this registration relationship, the current scanning parameters of the next cycle are corrected for subsequent magnetic resonance scanning.

[0208] In this embodiment, when the images at some tomographic positions in the three-dimensional amplitude map of the current cycle match those in the previous cycle and the images at the remaining tomographic positions do not match those in the previous cycle, the three-dimensional amplitude map of the next cycle with more stable image quality is registered with the three-dimensional amplitude map of the previous cycle to obtain a more accurate registration relationship and more reasonably correct the current scanning parameters.

[0209] Based on any one of the embodiments, in one embodiment, S13 includes:

[0210] In the three-dimensional amplitude of the current cycle, when the images at some tomographic positions match those in the previous cycle and the images at the remaining tomographic positions do not match those in the previous cycle, according to the registration relationship between the images at the remaining tomographic positions and the previous cycle, the scanning parameters of the previous cycle are corrected to obtain new scanning parameters.

[0211] Specifically, still referring to Figure 2 , in the three-dimensional amplitude map of the current period, part A directly corresponds to a partial area at the same position in the previous cycle, corresponding to the state of the patient before movement. Part B cannot directly correspond to the area at the same position in the previous cycle. Part B corresponds to the state of the patient after movement. At this time, the current scanning parameters are corrected according to the registration relationship between part B (that is, the images at the above-mentioned remaining tomographic positions) and the three-dimensional amplitude map of the previous cycle.

[0212] In this embodiment, when the images at some tomographic positions in the three-dimensional amplitude map of the current cycle match those in the previous cycle and the images at the remaining tomographic positions do not match those in the previous cycle, the images at the remaining tomographic positions are registered with the three-dimensional amplitude map of the previous cycle to more accurately obtain the "movement parameters of the patient" and more reasonably correct the current scanning parameters.

[0213] A preferred embodiment of the present invention will be described below. Figure 3 It is a program flowchart corresponding to a preferred embodiment of a method for correcting scanning parameters of a magnetic resonance device provided by the present invention. As Figure 3 shown, the host receives and obtains the positioning sequence scan images from the magnetic resonance device, reconstructs the positioning three-dimensional structure diagram based on the positioning sequence scan images, and determines the initial scanning parameters. The host sends the initial scanning parameters to the magnetic resonance device for the first-stage fast magnetic resonance scan. Subsequently, when the scanning parameters are corrected and updated, the host also sends the corrected and updated current scanning parameters to the magnetic resonance device, facilitating the magnetic resonance device to perform fast magnetic resonance scans according to the corrected and updated current scanning parameters. The host processes the data collected by the magnetic resonance device, obtains a set of continuous magnetic resonance images in each cycle, establishes a three-dimensional temperature map and a three-dimensional amplitude map based on the magnetic resonance images of each stage, and determines whether it is necessary to correct the current scanning parameters. Specifically: first, compare the background region of the three-dimensional amplitude map of the current cycle with that of the previous cycle. If the change in the cumulative gray value of the background region does not exceed the threshold, it is considered that the patient has not moved, and the current scanning parameters can be used for the next-stage fast magnetic resonance imaging. If the change in the cumulative gray value exceeds the threshold, it is necessary to further determine the inclusion relationship between the three-dimensional amplitude map of the current stage and the target area. If the target area is completely included in the three-dimensional amplitude map of the current cycle, it means that the current magnetic resonance imaging range can cover the target area, and the corresponding three-dimensional temperature Figure 3 three-dimensional amplitude map can provide information parameters for the doctor, and there is no need to correct the scanning parameters; if the target area is partially included in the three-dimensional amplitude map of the current cycle, it means that the current magnetic resonance imaging range cannot cover some target areas, and it is necessary to register the three-dimensional amplitude map of the current cycle with that of the previous cycle, and correct (update) the current scanning parameters according to the registration relationship, and use the corrected (updated) current scanning parameters for the next cycle of fast magnetic resonance imaging; if the target area is not included in the three-dimensional amplitude map of the current cycle at all, it means that the patient has moved greatly, and the current scanning parameters cannot be corrected based on the registration relationship between the three-dimensional amplitude map of the current cycle and that of the previous cycle (cannot be registered, or the registration accuracy is low and does not meet the requirements). At this time, it is necessary to register the three-dimensional amplitude map of the current cycle with the positioning three-dimensional structure diagram established based on the positioning sequence scan, and determine the new current scanning parameters according to this registration relationship in combination with the initial scanning parameters, and use them for the next cycle of fast magnetic resonance imaging.

[0214] A laser ablation device provided by the present invention is used for magnetic resonance-guided laser interstitial thermotherapy. As Figure 4 shown, the laser ablation device 400 includes:

[0215] A host computer 410 stores executable instructions which, when executed, implement the method for correcting magnetic resonance device parameters in any of the foregoing items to correct the scanning parameters of a magnetic resonance device.

[0216] The laser ablation device 400 may further include a display device for displaying the processed three-dimensional temperature map and three-dimensional amplitude map, facilitating observation by doctors.

[0217] The present invention also provides a magnetic resonance-guided laser ablation system. The magnetic resonance-guided laser ablation system described below may be referred to and corresponding to the method for correcting magnetic resonance device scanning parameters and the laser ablation device described above.

[0218] As Figure 5 shown, the system includes: a magnetic resonance device 510 and the aforementioned laser ablation device 400.

[0219] The magnetic resonance device 510 is configured to acquire magnetic resonance images according to the scanning parameters sent by the laser ablation device 400 and send the acquired magnetic resonance images to the laser ablation device 400; the laser ablation device is configured to process the magnetic resonance images, update the scanning parameters, and send the updated scanning parameters to the magnetic resonance device; the laser ablation device is further configured to display the processed magnetic resonance images for doctors to observe and perform laser ablation operations.

[0220] Based on any embodiment, in one embodiment, the system further includes a laser ablation kit, which includes: a treatment light source module, a cooling circulation module, a cooling sleeve, and an ablation optical fiber.

[0221] Specifically, the treatment light source module is configured to generate laser with the required power, the cooling circulation module is configured to pump and recycle the coolant, the cooling sleeve is configured to provide a circulation path for the coolant to cool the ablation optical fiber, and the ablation optical fiber is configured to introduce the laser into the target area to ablate the target area.

[0222] Further, the laser ablation kit may further include a temperature measurement module for measuring the temperature at the ablation site of the optical fiber, and the measurement result can be mutually verified with the temperature result monitored by magnetic resonance.

[0223] Further, the laser ablation kit may further include an optical fiber adjustment module for adjusting the depth of the optical fiber. In the case where the ablation optical fiber is a directional light-emitting optical fiber, the optical fiber adjustment module can be set to be able to adjust both the depth and the angle of the optical fiber.

[0224] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for correcting scanning parameters of a magnetic resonance device, which is used for magnetic resonance-guided laser interstitial thermal therapy, characterized in that Including: Periodically performing fast magnetic resonance imaging on a target area, and obtaining a set of consecutive magnetic resonance images in each period; For each set of consecutive magnetic resonance images, establishing a three-dimensional temperature map according to the phase map in the magnetic resonance image, and establishing a three-dimensional amplitude map according to the amplitude map in the magnetic resonance image; For each period, generating new scanning parameters according to the registration relationship between the three-dimensional amplitude maps of the current period and the reference period, for fast magnetic resonance imaging in the next period.

2. The method for correcting scanning parameters of a magnetic resonance device according to claim 1, characterized in that, Before the step of periodically performing fast magnetic resonance imaging on the target area and obtaining a set of consecutive magnetic resonance images in each period, it further includes: Obtaining a positioning sequence scan image, establishing a positioning three-dimensional structure diagram according to the positioning sequence scan image, and registering the positioning three-dimensional structure diagram with the preoperative three-dimensional image, so as to determine the position of the target area; wherein, the target area is outlined or automatically segmented in the preoperative three-dimensional image; Determining initial scanning parameters according to the position of the target area, or determining initial scanning parameters according to a user input instruction.

3. The magnetic resonance three-dimensional temperature detection device according to claim 1, wherein The step of periodically performing fast magnetic resonance imaging on the target area and obtaining a set of consecutive magnetic resonance images in each period includes: Determining a target area to be sampled in the current period according to a preset magnetic resonance downsampling rule; Performing magnetic resonance scanning on the target area to obtain a magnetic resonance image of the target area; Obtaining consecutive magnetic resonance images of the current period according to the magnetic resonance image of the target area.

4. The magnetic resonance three-dimensional temperature detection device according to claim 3, characterized in that, The preset magnetic resonance downsampling rule is inter-slice downsampling and / or intra-slice downsampling.

5. The magnetic resonance three-dimensional temperature detection device according to claim 3, characterized in that, The step of obtaining consecutive magnetic resonance images of the current period according to the magnetic resonance image of the target area includes: Obtaining consecutive magnetic resonance images covering the target area through a reconstruction algorithm according to the magnetic resonance image of the target area; or, Obtaining consecutive magnetic resonance images covering the target area according to the magnetic resonance image of the target area and combining the magnetic resonance images of its complementary period.

6. The three-dimensional magnetic resonance temperature monitoring device according to claim 2, wherein, The step of periodically performing fast magnetic resonance imaging on the target area and obtaining a set of consecutive magnetic resonance images in each period includes: Periodically scanning the target area through a magnetic resonance fast imaging sequence; Correcting the magnetic resonance image of the current period by using the reference period to obtain a corrected magnetic resonance image.

7. The magnetic resonance three-dimensional temperature monitoring device according to claim 6, characterized in that, The reference period is any corrected period, and the step of correcting the magnetic resonance image of the current period by using the reference period includes: Obtaining distortion correction information according to the first position of the target structure in the magnetic resonance image of the reference period and the second position of the target structure in the magnetic resonance image of the reference period; wherein, the reference period is a positioning sequence scan image obtained by pre-scanning a reference area, and the reference area covers the target area; Correcting the magnetic resonance image of the current period according to the distortion correction information.

8. The method for correcting scanning parameters of a magnetic resonance device according to claim 1, characterized in that, After the step of, for each set of consecutive magnetic resonance images, establishing a three-dimensional temperature map according to the phase map in the magnetic resonance image and establishing a three-dimensional amplitude map according to the amplitude map in the magnetic resonance image, the method further includes: Comparing the background area of the current period with that of the previous period; If the change in the cumulative gray value of the background region does not exceed the preset threshold, then enter the next cycle and perform the step of periodically performing fast magnetic resonance imaging on the target region; If the change in the cumulative gray value of the background region exceeds the preset threshold, jump to the step of generating new scanning parameters according to the registration relationship between the three-dimensional amplitude maps of the current cycle and the reference cycle.

9. The method for correcting scanning parameters of a magnetic resonance device according to claim 8, characterized in that, The generating new scanning parameters according to the registration relationship between the three-dimensional amplitude maps of the current cycle and the reference cycle includes: Register the background regions of the three-dimensional amplitude maps of the current cycle and the reference cycle, and correct based on this registration relationship on the basis of the scanning parameters of the reference cycle to obtain the new scanning parameters.

10. The method for correcting the scanning parameters of the magnetic resonance device according to claim 1, characterized in that, For each set of consecutive magnetic resonance images, after establishing a three-dimensional temperature map according to the phase map in the magnetic resonance images and establishing a three-dimensional amplitude map according to the amplitude map in the magnetic resonance images, the method further includes: Judge the inclusion situation of the target region in the three-dimensional amplitude map of the current cycle; If the three-dimensional amplitude map of the current cycle completely includes the target region, enter the next cycle and perform the periodic fast magnetic resonance imaging on the target region; If the three-dimensional amplitude map of the current cycle partially includes the target region, jump to the step of generating new scanning parameters according to the registration relationship between the three-dimensional amplitude maps of the current cycle and the reference cycle; If the three-dimensional amplitude map of the current cycle completely does not include the target region, register the three-dimensional amplitude map of the current cycle with the positioning three-dimensional structure diagram, and determine new scanning parameters according to this registration relationship; wherein, the positioning three-dimensional structure diagram is a three-dimensional amplitude map established according to the positioning sequence scanning image.

11. The method for correcting scanning parameters of a magnetic resonance device according to claim 1, characterized in that, The generating new scanning parameters according to the registration relationship between the three-dimensional amplitude maps of the current cycle and the reference cycle includes: In the three-dimensional amplitude map of the current cycle, when the images of some tomographic positions match those of the previous cycle and the images of the remaining tomographic positions do not match those of the previous cycle, Correct the scanning parameters of the previous cycle according to the registration relationship between the images of the remaining tomographic positions and the previous cycle to obtain new scanning parameters; or, do not perform registration using the magnetic resonance images of the current cycle, register the three-dimensional amplitude maps of the next cycle and the previous cycle, and correct based on this registration relationship on the basis of the scanning parameters of the previous cycle to obtain the new scanning parameters.

12. An ablation device, including a host, the host stores executable instructions, and when the executable instructions are executed, the magnetic resonance device parameter correction method according to any one of claims 1-11 is implemented to correct the scanning parameters of the magnetic resonance device.

13. A magnetic resonance-guided laser ablation system, characterized in that, It includes: A magnetic resonance device, and a laser ablation device according to claim 12.

Images