Fast magnetic resonance imaging method and operation guiding system

Abstract

The fast magnetic resonance imaging method provided by the invention comprises the following steps: periodically scanning a target area containing a focus through a magnetic resonance fast imaging sequence to obtain an initial magnetic resonance image sequence of a target period, the target period being any period of periodically scanning the target area; the initial magnetic resonance image sequence of the target period is corrected according to a reference period, a corrected magnetic resonance image sequence of the target period is obtained, and the reference period is a period in which a reference area containing a focus is scanned by magnetic resonance in advance to obtain a space standard image; according to the rapid magnetic resonance imaging method provided by the invention, the target area containing the focus is scanned through the magnetic resonance rapid imaging sequence, the scanned magnetic resonance image is corrected, distortion generated in the rapid scanning process is eliminated, and the efficiency and precision of magnetic resonance imaging are improved.

Description

Technical Field

[0001] This specification relates to the field of medical device technology, and in particular to a rapid magnetic resonance imaging method and a surgical guidance system. Background Technology

[0002] Magnetic resonance imaging (MRI) is a commonly used technique in the medical field, helping to identify tissue structures. However, existing MRI methods often require long scanning cycles, are too time-consuming, or have large errors in some rapid scanning sequences, failing to meet the required spatial accuracy. This makes them unsuitable for real-time guidance of surgical instrument implantation and puncture, and unsuitable for intraoperative scanning (existing methods require sedation, which some patients cannot tolerate or are allergic to, or whose physical condition is poor and cannot remain still for extended periods). Furthermore, they cannot achieve real-time three-dimensional structural monitoring of ablation effects. To address these issues, this specification proposes a rapid MRI method to achieve rapid MRI imaging of the target space. Summary of the Invention

[0003] In view of this, embodiments of the present invention provide a rapid magnetic resonance imaging method, a surgical guidance system, a magnetic resonance-guided laser ablation system, a computer-readable storage medium, and a computer program to address the technical deficiencies existing in the prior art.

[0004] In a first aspect, the present invention provides a fast magnetic resonance imaging method, comprising:

[0005] The target region containing the lesion is periodically scanned by a rapid magnetic resonance imaging sequence to obtain an initial magnetic resonance image sequence of the target period, wherein the target period is any period of periodic scanning of the target region;

[0006] The initial magnetic resonance image sequence of the target period is corrected according to the reference period to obtain the corrected magnetic resonance image sequence of the target period, wherein the reference period is the period in which a spatial standard image is obtained in advance using a magnetic resonance scan of a reference region containing the lesion.

[0007] Correcting the initial magnetic resonance image sequence of the target period based on the reference period can be done in three ways: by correcting the initial magnetic resonance image sequence of the target period based on the spatial standard image, by correcting it based on the correction information of the previous period, or by correcting it based on the correction information of any period.

[0008] Secondly, the present invention provides another fast magnetic resonance imaging method, comprising:

[0009] A downsampling strategy is used to scan the target region containing lesions to obtain a downsampling sequence of the target period, wherein the target period is any period of periodic scanning of the target region;

[0010] A complete magnetic resonance image sequence is reconstructed based on the downsampling sequence of the target period to obtain the reconstructed magnetic resonance image sequence of the target period.

[0011] Downsampling can be inter-layer downsampling and / or intra-layer downsampling.

[0012] Thirdly, the present invention provides a magnetic resonance-guided laser ablation system, the system comprising a host computer having an application program configured to implement the rapid magnetic resonance imaging method described in the first or second aspect above.

[0013] Fourthly, the present invention provides a surgical guidance system, the system comprising a host computer, the host computer being equipped with an application program for implementing the rapid magnetic resonance imaging method described in the first or second aspect above. By executing the rapid magnetic resonance imaging method, various puncture and ablation surgeries, such as microwave ablation, hematoma aspiration, biopsy, deep electrode implantation, fiber optic implantation, radiofrequency electrode implantation, cryoablation, etc., can be monitored and results confirmed, and intraoperative MR imaging can be performed to confirm the surgical resection results, structural information changes, etc., providing information for surgical guidance; thus realizing surgical guidance based on magnetic resonance images.

[0014] Fifthly, the present invention provides a computer-readable storage medium disposed in the host of a magnetic resonance-guided laser ablation system, which stores computer-executable instructions that, when executed by a processor, implement the fast magnetic resonance imaging method described in the first or second aspect.

[0015] In a sixth aspect, the present invention provides a computer program, wherein when the computer program is executed in a computer, it causes the computer to perform the fast magnetic resonance imaging method described in the first or second aspect.

[0016] One embodiment of this specification implements a method for periodically scanning a target region containing a lesion using a rapid magnetic resonance imaging (MRI) sequence to obtain an initial MRI image sequence for a target period, wherein the target period is any period of periodic scanning of the target region; the initial MRI image sequence for the target period is then corrected according to a reference period to obtain a corrected MRI image sequence for the target period, wherein the reference period is the period for obtaining a spatial standard image using a reference region containing the lesion via MRI scanning. Thus, the initial MRI image sequence for the target period can be corrected based on the period for obtaining a spatial standard image using a reference region containing the lesion via MRI scanning. This means that the MRI image sequence obtained through rapid scanning can be corrected based on unchanging spatial position information, eliminating distortions generated during rapid scanning, increasing the scanning range without reducing spatial resolution, and reducing the time required for MRI scanning in one period. This achieves rapid scanning of MRI image sequences, improving the accuracy, convenience, and flexibility of MRI image acquisition, and facilitating users to observe the tissue state at various locations and directions.

[0017] Another embodiment of this specification implements a method that uses a downsampling strategy to scan a target region containing lesions to obtain a downsampling sequence of a target period, wherein the target period is any period of periodic scanning of the target region; a complete magnetic resonance image sequence is reconstructed based on the downsampling sequence of the target period to obtain a reconstructed magnetic resonance image sequence of the target period. Thus, since the scanned target region remains unchanged, spatial redundancy exists between frames. The downsampling acceleration method can be used to speed up the acquisition of magnetic resonance images. Each period only scans a portion of the data, greatly accelerating the acquisition of magnetic resonance images. By utilizing the invariance of spatial information in the target region, complete magnetic resonance image information is reconstructed, thereby ensuring the quality of the acquired images. High spatiotemporal resolution imaging is achieved without changing image quality or scanning time, thus enabling rapid scanning of magnetic resonance image sequences. During the magnetic resonance scanning process, images can be acquired from any scanning direction, improving the flexibility of image acquisition and observation, and facilitating users to observe the tissue state at various locations and directions.

[0018] The advantages of this invention include, but are not limited to, the following:

[0019] 1. Spatial location reconstruction through amplitude maps can provide real-time guidance for surgical procedures that require image monitoring, such as surgical instrument implantation and tissue puncture.

[0020] 2. The rapid magnetic resonance scanning method greatly reduces the scanning time, which can be used for intraoperative scanning, and patients in poor physical condition can also obtain magnetic resonance images.

[0021] 3. It can achieve near real-time monitoring of ablation therapy, especially for laser interstitial thermotherapy, confocal ultrasound, etc.

[0022] 4. Visualizing information about deep lesions through 3D displays and / or AR devices provides real-time assistance to doctors, improving safety and reducing difficulty. Attached Figure Description

[0023] Figure 1 This is a flowchart of a fast magnetic resonance imaging method provided in one embodiment of this specification;

[0024] Figure 2 This is a flowchart of a magnetic resonance-guided ablation imaging method provided in one embodiment of this specification;

[0025] Figure 3 This is a flowchart of another fast magnetic resonance imaging method provided in one embodiment of this specification;

[0026] Figure 4 This is a schematic diagram of the main unit of a fast magnetic resonance imaging system provided in one embodiment of this specification;

[0027] Figure 5 This is a schematic diagram of the main unit of a magnetic resonance-guided laser ablation system provided in one embodiment of this specification;

[0028] Figure 6 This is a schematic diagram of the main unit of another magnetic resonance-guided laser ablation system provided in one embodiment of this specification;

[0029] Figure 7 This is a schematic diagram of a magnetic resonance-guided laser ablation system provided in one embodiment of this specification;

[0030] Figure 8 This is a schematic diagram of another magnetic resonance-guided laser ablation system provided in one embodiment of this specification. Detailed Implementation

[0031] Many specific details are set forth in the following description to provide a full understanding of this specification. However, this specification can be implemented in many other ways than those described herein, and those skilled in the art can make similar extensions without departing from the spirit of this specification. Therefore, this specification is not limited to the specific implementations disclosed below.

[0032] The terminology used in one or more embodiments of this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the one or more embodiments of this specification. The singular forms “a” and “the” as used in one or more embodiments of this specification and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in one or more embodiments of this specification refers to and includes any or all possible combinations of one or more associated listed items.

[0033] It should be understood that although the terms first, second, etc., may be used to describe various information in one or more embodiments of this specification, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first may also be referred to as second without departing from the scope of one or more embodiments of this specification, and similarly, second may also be referred to as first. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to a determination."

[0034] First, the terms and concepts used in one or more embodiments of this specification will be explained.

[0035] Nuclear Magnetic Resonance Imaging (NMRI): Also known as spin imaging, magnetic resonance imaging (MRI), or magnetic resonance imaging, it utilizes the principle of nuclear magnetic resonance (NMR). Based on the different attenuations of released energy in different structural environments within a substance, and by detecting the emitted electromagnetic waves through an external gradient magnetic field, the location and type of atomic nuclei that make up the object can be determined, and an image of the object's internal structure can be created.

[0036] MR-guided laser interstitial thermotherapy (MRgLITT) is a novel treatment technique that uses optical fibers to deliver light into the body, causing local biological tissue to coagulate and necrose upon heating. It can remove tumors or lesions in situ with minimal invasiveness. Compared to traditional surgical resection, this method has advantages such as shorter operation time, smaller surgical trauma, less bleeding, less pain for the patient, better postoperative recovery, and certain anti-inflammatory and antibacterial effects. It shows great promise in disease treatment, especially in tumor research, and is currently used to treat many types of diseases, such as tumors in the liver, brain, breast, and retina, as well as epilepsy. In MRgLITT, laser light is typically delivered into the tissue via optical fibers; the tissue absorbs the laser energy and converts it into heat, thereby achieving the purpose of destruction.

[0037] This specification provides a rapid magnetic resonance imaging method, and also relates to a magnetic resonance-guided laser ablation system, a computer-readable storage medium, and a computer program, which are described in detail in the following embodiments.

[0038] See Figure 1 , Figure 1 A flowchart of a fast magnetic resonance imaging method according to an embodiment of this specification is shown, specifically including the following steps 102-104.

[0039] Step 102: Periodically scan the target region containing the lesion using a rapid magnetic resonance imaging sequence to obtain an initial magnetic resonance image sequence of the target period, wherein the target period is any period of periodic scanning of the target region.

[0040] Specifically, rapid magnetic resonance imaging (MRI) sequences refer to MRI scanning methods that can efficiently acquire and generate temperature and structural maps. Temperature maps can be obtained based on phase maps, and structural maps can be obtained based on amplitude maps. By scanning a target region containing a lesion using rapid MRI sequences, the resulting MRI image sequence is a continuous set of MRI images obtained from the target cycle scan. This continuity means that the MRI scan images of each slice are consecutively adjacent. The initial MRI image sequence obtained in each cycle can be subsequently corrected based on invariant spatial location information, so that the corresponding temperature map can be established using the phase difference between the MRI image sequences of two consecutive cycles, facilitating real-time updates of the monitoring data.

[0041] In one possible implementation, the initial magnetic resonance image sequence of the target period is obtained by scanning the target region based on gradient echo imaging. That is, the fast magnetic resonance imaging sequence can be gradient echo imaging (EPI), and the obtained initial magnetic resonance image sequence is the EPI sequence. EPI is one of the fastest magnetic resonance imaging sequences to date. It is a special form of gradient echo, which uses a fast reverse gradient to generate a series of gradient echoes in a single relaxation time (TR) and encodes them in phase, filling them into the corresponding k-space to achieve cross-sectional imaging.

[0042] In another possible implementation, the initial magnetic resonance image sequence can also be obtained by scanning the target region based on other fast scanning algorithms, such as shortening the repetition time (TR), acquiring fewer phase coding lines, parallel acquisition techniques, gradient echo magnetic resonance pulse sequence (GRE), gradient echo translation imaging (PRESTO), balanced steady-state free precession imaging (B-SSFP), etc.

[0043] Among them, parallel acquisition technology: Parallel acquisition technology uses multi-channel phased array coils to reduce the acquisition density of K-space limiting coding lines, accelerate the acquisition speed of magnetic resonance images, and shorten the image acquisition time by 1-16 times. Under the premise of unchanged acquisition time, it can increase spatial resolution or increase the three-dimensional acquisition imaging range, and can also increase the number of repeated acquisitions to improve image quality and reduce artifacts.

[0044] Gradient echo magnetic resonance pulse sequence (GRE): Also known as gradient echo sequence or field echo sequence. It is one of the fastest scanning sequences currently available, offering high spatial resolution while shortening the repetition time, without signal loss, resulting in a high signal-to-noise ratio. Due to the shortened repetition time (TR), the scan time is significantly reduced. The GRE sequence utilizes small-angle (<90°) radio frequency excitation pulses and continuous switching of the gradient field to generate the signal.

[0045] Gradient Echo Shifting (PRESTO): By adding an extra negative gradient pulse to the gradient at the pulse sequence level, and then providing a positive gradient pulse of equal area before the next excitation pulse, the gradient echo will be generated in the next TR time. This is equivalent to shifting the echo generated in the current TR time to the next TR time time. This technique is called Gradient Echo Shifting, and the sequence is called PRESTO.

[0046] Balanced Steady-State Free Precession (B-SSFP): When both the longitudinal and transverse magnetization vectors reach a steady state, this is called steady-state free precession. When reasonable TR, TE, and flip angles are set, the various echoes (FID, SE, and STE) generated by multiple radio frequency pulses are fused into a single echo, reaching a balanced state. This gradient back-shaking sequence is called the Balanced Steady-State Free Precession Sequence (b-SSFP). The signal acquired by B-SSFP is a fused signal of various echoes, and its information density is higher.

[0047] It should be noted that the rapid magnetic resonance imaging (MRI) sequence can acquire MRI image data with higher resolution and more acquisition layers, meeting the needs of applications with high real-time requirements for MRI image acquisition. For example, in laser ablation surgery, existing technologies acquire 3 MRI images per cycle, with a data resolution (i.e., layer thickness) of 3 mm per layer, and an acquisition time of approximately 4-6 seconds per cycle. According to one embodiment of this application, a rapid MRI sequence is used to scan, acquiring 20 MRI images per cycle, with a data resolution of 1 mm per layer, and an acquisition time of 3-6 seconds per cycle. This provides higher data resolution while still meeting the requirements. When phase maps are not needed to obtain temperature information, and only structural maps are required, the acquisition time can be further significantly compressed, and real-time acquisition of structural maps can be achieved through amplitude maps.

[0048] In practical applications, in order to obtain the initial magnetic resonance image sequence of the target period by scanning the target area containing the lesion, it is also necessary to determine the location of the target area and the scanning parameters. Specifically, the spatial location of the biological tissue to be operated on (such as liver, spleen, prostate, head, etc.) can be determined, and then the spatial location of the target area to be processed in the biological tissue to be operated on can be determined. This target area and its surrounding tissue are the target area containing the lesion, so that the target area can be accurately monitored by the magnetic resonance equipment.

[0049] In practice, a global localization sequence scan can be performed on the patient using an MRI scanner to obtain localization sequence images. This localization sequence scan is a large-area MRI scan of the patient used to locate the position and orientation of the lesion structure (target area) to determine the location of the target region containing the lesion. The localization sequence scan can be T1WI (T1-weighted imaging), T2WI (T2-weighted imaging), DWI (diffusion-weighted imaging), etc.

[0050] After acquiring the localization sequence scan images, a localization 3D structural map can be created based on the scan images. This map is then registered with the preoperative 3D images, displaying the preoperative planning parameters. The corresponding scanning parameters are then determined, or determined based on user input. These preoperative planning parameters include the target area, key points / regions to be protected, areas requiring ablation, and the planned implantation path.

[0051] Preferably, the imaging method of the localization sequence scan image is consistent with the magnetic resonance scanning parameters of the preoperative three-dimensional image to improve the registration accuracy between the localization three-dimensional structural map and the preoperative three-dimensional image. The localization sequence scan image may contain a series of amplitude maps, based on which a three-dimensional structural map for localizing the target tissue (i.e., the localization three-dimensional structural map) can be reconstructed. In this three-dimensional structural map, the biological tissue to be operated on, such as the liver, spleen, prostate, head, etc., can be observed, along with the target area in the biological tissue to be operated on, the actual implantation path of the optical fiber, etc.

[0052] The localization sequence scan here has a sufficiently large scanning range to cover the biological tissue to be operated on (e.g., ablation, puncture, resection, etc.). Based on the localization sequence scan images, the location of the biological tissue to be operated on and the location of the target area to be treated within that biological tissue can be determined, thus identifying the target region containing the lesion. Furthermore, since medical imaging of the target tissue has been performed preoperatively, and a preoperative 3D image has been created, and the target area has been delineated from this preoperative 3D image, or the target area has been automatically determined through semantic segmentation of the preoperative 3D image using a semantic segmentation model, the location of the target area in the localization sequence scan image can be determined by registering it with the preoperative 3D image. Alternatively, the target area location can be determined directly based on the localization sequence scan image through delineation or automatic semantic segmentation. Finally, the location of the target region can be determined based on the location of the target area and its surrounding tissue.

[0053] It should be noted that scanning parameters can be determined based on the target area's information (shape, size, and location). These parameters include scanning direction, number of scan layers, scanning position, and scanning resolution. The scanning direction refers to the direction of the tomographic cut; the number of scan layers refers to how many layers of MRI images are acquired in each scan cycle to cover the target area (e.g., 10, 15, 18 layers, etc.); the scanning position refers to the acquisition position of the multi-layer MRI images; and the scanning resolution refers to the slice thickness of each MRI image (e.g., 1mm, 2mm, 3mm, etc.). Scanning parameters can be automatically set by the application program, for example, automatically setting the number of scan layers based on the target area size and scanning resolution; some parameters can also be stored, commonly recommended parameters; scanning parameters can also be determined based on user input commands, for example, the user can select a scanning direction that facilitates observation of a specific structure according to the desired tissue structure. Furthermore, a certain margin in the number of scan layers can be set to ensure that the MRI scan range encompasses the target area.

[0054] After the application on the host determines the location and scanning parameters of the target area, it sends the location and scanning parameters to the magnetic resonance imaging (MRI) device. This allows the MRI device to perform rapid MRI sequence scanning on the target area during subsequent intraoperative ablation, thereby monitoring the target area.

[0055] In this way, by reconstructing the three-dimensional structural map for localization through positioning sequence scanning and registering it with the preoperative three-dimensional image, the location of the target area containing the lesion was accurately determined. Based on this, the scanning parameters were reasonably set, laying the foundation for obtaining magnetic resonance image sequences through rapid intraoperative scanning and improving the imaging quality.

[0056] It should be noted that since only the state of the target area is considered during the operation, the intraoperative MRI scan only needs to cover the target area. In other words, the scanning range of the intraoperative MRI is smaller than that of the localization sequence scan, which makes it easier to shorten the intraoperative MRI scan cycle.

[0057] In one optional implementation of this embodiment, in addition to improving the scanning speed through rapid magnetic resonance imaging sequences, inter-slice downsampling can be used to further improve the scanning speed to meet clinical needs. Specifically, rapid magnetic resonance imaging sequences are used to periodically scan the target region containing the lesion to obtain an initial magnetic resonance image sequence for the target period, including:

[0058] Based on the established inter-layer downsampling rules, determine the target layer to be sampled in the target period;

[0059] The target layer is scanned using a rapid magnetic resonance imaging sequence to obtain an initial magnetic resonance image sequence of the target period.

[0060] Specifically, the inter-layer downsampling rule is a pre-defined rule for determining the layers to be scanned. That is, for each layer included in the target region, it is a scanning strategy that determines which layers to scan and which not to scan within a cycle. For example, the inter-layer downsampling rule can be to sample odd-numbered layers and even-numbered layers at intervals; or, the inter-layer downsampling rule can also be to use a first strategy when the number of layers to be sampled exceeds a layer number threshold, and a second strategy when it does not exceed the layer number threshold.

[0061] The layer threshold can be a pre-set value used to determine whether there are too many layers to scan in the target area, and thus adopt different inter-layer downsampling strategies, such as layer thresholds of 10, 15, 18, etc. The first strategy is a downsampling strategy set for cases where there are too many layers to sample, and the second strategy is a downsampling strategy set for cases where there are too few layers to sample. Therefore, the interval between layers in the first strategy is greater than the interval between layers in the second strategy.

[0062] In practical applications, when scanning the target region using a fast magnetic resonance imaging sequence during the target period, the target layers to be sampled during the target period can be determined first according to the set inter-slice downsampling rules. That is, which layers of the target region need to be scanned during the target period. Then, the target layer is scanned using a fast magnetic resonance imaging sequence to obtain the initial magnetic resonance image sequence of the target period.

[0063] It should be noted that since the target area being scanned remains unchanged, spatial redundancy exists between frames. Inter-slice downsampling can be used to accelerate the acquisition of magnetic resonance images. For example, using EPI or GRE sequences, inter-slice downsampling can improve image acquisition speed. In this way, only a portion of the target area is scanned in each cycle, accelerating the acquisition of magnetic resonance images. Then, the complete image can be reconstructed using the data from the target cycle and the previous cycle, thus ensuring the quality of the acquired images. This achieves high spatiotemporal resolution and wide-range temperature imaging without altering image quality or scanning time.

[0064] In one optional implementation of this embodiment, the set inter-layer downsampling rule is to sample odd-numbered layers and even-numbered layers at intervals; based on the set inter-layer downsampling rule, the target layer to be sampled in the target period is determined, including:

[0065] Determine the sampling layer of the previous scan cycle;

[0066] If the number of sampling layers in the previous cycle is odd, the target layer to be sampled in the target cycle is determined to be even.

[0067] If the number of sampling layers in the previous cycle is even, the target layer to be sampled in the target cycle is determined to be odd.

[0068] It should be noted that the set inter-layer downsampling rule can be to sample odd-numbered layers and even-numbered layers at different intervals, that is, the layers sampled in two adjacent periods are different.

[0069] In practical applications, the sampling layers of the previous scan cycle can be determined first. If the sampling layers of the previous scan cycle are odd-numbered, then the target cycle samples even-numbered layers; if the sampling layers of the previous scan cycle are even-numbered, then the target cycle samples odd-numbered layers. For example, if the target region includes sampling layers 1-10, one cycle scans layers 1 / 3 / 5 / 7 / 9, and the next cycle samples layers 2 / 4 / 6 / 8 / 10.

[0070] In the embodiments of this specification, the inter-slice downsampling rule can be pre-configured to sample odd-numbered and even-numbered layers at intervals, with one cycle sampling odd-numbered layers and another cycle sampling even-numbered layers. Each cycle only scans a portion of the target region, and the layers sampled in two adjacent regions do not overlap, maximizing downsampling and thereby improving the acquisition speed of magnetic resonance image sequences to meet the clinical needs of magnetic resonance-based temperature measurement and ablation calculations.

[0071] In one optional implementation of this embodiment, the set inter-layer downsampling rule is as follows: a first strategy is used when the number of layers to be sampled exceeds a layer number threshold, and a second strategy is used when the number of layers does not exceed the layer number threshold; according to the set inter-layer downsampling rule, the target layer to be sampled in the target period is determined, including:

[0072] Determine the number of sampling layers in the target region;

[0073] If the number of layers to be sampled exceeds the layer threshold, the target layer to be sampled in the target period is determined according to the first strategy;

[0074] If the number of layers to be sampled does not exceed the layer threshold, the target layer to be sampled in the target week is determined according to the second strategy.

[0075] Specifically, the layer threshold can be a pre-set value used to determine whether there are too many layers to be scanned in the target area, thereby adopting different inter-layer downsampling strategies, such as layer thresholds of 10, 15, 18, etc. The first strategy is a downsampling strategy set for cases where there are too many layers to be sampled, and the second strategy is a downsampling strategy set for cases where there are too few layers to be sampled. Therefore, the layer interval of the first strategy is greater than that of the second strategy. That is, because there are too many layers to be sampled in the target area, the first strategy ignores many layers in one cycle to ensure scanning speed. For example, the first strategy can sample layers at different cycle intervals of k-1 layers, that is, the first cycle samples layer 1, the next cycle samples layer 1+k, the next cycle samples layer 1+2k, and so on. The second strategy can sample layers at different cycle intervals of m-1 layers, where m is less than k.

[0076] In practice, the first or second strategy can be configured based on actual needs, and the first or second strategy can also sample the odd-numbered and even-numbered layers respectively for the above-mentioned interval period.

[0077] For example, assuming the target area includes 1-12 sampling layers and the layer threshold is 10, if the number of layers to be sampled in the target area exceeds the layer threshold, layers 1 / 4 / 7 / 10 are scanned in one cycle, layers 2 / 5 / 8 / 11 are sampled in the second cycle, and layers 3 / 6 / 9 / 12 are sampled in the third cycle. Alternatively, assuming the layer threshold is 15, if the number of layers to be sampled in the target area does not exceed the layer threshold, layers 1 / 3 / 5 / 7 / 9 / 11 can be sampled in one cycle, and layers 2 / 4 / 6 / 8 / 12 can be sampled in the next cycle. In other words, if the number of layers to be sampled in the target area exceeds the layer threshold, sampling is performed every 2 layers in each cycle; if 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 cycle.

[0078] It should be noted that if the number of layers to be sampled exceeds the layer threshold, it means that the target area contains a large number of layers to be sampled. In this case, the first strategy can be used to determine the target layer to be sampled in the target week. If the number of layers to be sampled does not exceed the layer threshold, it means that the target area contains a small number of layers to be sampled. The second strategy can be used to determine the target layer to be sampled in the target week. Different inter-layer downsampling strategies can be adopted for different situations of the target area, which can adapt to more application scenarios and improve applicability and flexibility.

[0079] In one optional implementation of this embodiment, in addition to using inter-slice downsampling to improve scanning speed, intra-slice downsampling can also be used to further improve scanning speed to meet the requirements of temperature detection; the magnetic resonance rapid imaging sequence is scanned column by column; the target layer is scanned using the magnetic resonance rapid imaging sequence to obtain an initial magnetic resonance image sequence of the target period, including:

[0080] The data column to be collected for the target period is determined according to the set intra-layer downsampling rules;

[0081] The initial magnetic resonance image sequence of the target period is obtained by scanning the data column to be collected in the target layer using a rapid magnetic resonance imaging sequence.

[0082] It's important to note that fast magnetic resonance imaging (MRI) sequences, such as GRE, scan column-by-column. This means that when scanning a layer, the MRI sequence doesn't scan the entire layer at once, but rather scans only one column of data within that layer. For column-by-column MRI sequences, in addition to the inter-slice downsampling mentioned above, intra-slice downsampling can be further employed, acquiring only certain columns within a layer per scan to improve scanning speed. Conversely, if the MRI sequence is slice-by-slice, such as EPI, then when scanning a layer, it scans one layer at a time, making intra-slice downsampling impossible; only inter-slice downsampling is possible.

[0083] Specifically, the set intra-layer downsampling rules are pre-defined data column selection strategies for a given layer. In other words, for a given layer, the strategy determines which data columns to collect and which not to collect. For example, the set intra-layer downsampling rules could be to collect the 2nth column of data in the target period, the 2n+1th column in the next period, the 2n+2th column in the following period, and so on; or, to use a 3n, 3n+1, 3n+2 approach to increase the intra-layer data collection speed by 2 or 3 times.

[0084] In practical applications, the inter-slice downsampling rule selects a subset of data columns from each column of data in a given layer for acquisition. Based on the intra-slice downsampling rule, the specific data columns to be acquired for the target period can be determined. Then, a rapid magnetic resonance imaging (MRI) sequence is used to scan these data columns in the target layer to obtain the initial MRI image sequence for the target period. In this way, only a subset of data columns need to be acquired for the target layer, significantly improving the intra-slice data acquisition speed.

[0085] In the embodiments of this specification, an accelerated acquisition method using inter-layer downsampling and intra-layer downsampling can be employed. In each cycle, only a portion of the target region's layers and a portion of the data columns within those layers are scanned to accelerate the acquisition of magnetic resonance images. Then, a complete image is reconstructed based on the acquired data. During image reconstruction, a deep learning reconstruction algorithm is used, leveraging the invariance of spatial information in the target region and the continuity of temperature in physical space and time to reconstruct complete image information, thereby ensuring the quality of the acquired image. This achieves high spatiotemporal resolution and wide-range temperature imaging without altering image quality or scanning time.

[0086] It should be noted that in practical applications, besides using both inter-slice downsampling and intra-slice downsampling methods simultaneously to accelerate the acquisition of magnetic resonance images, either inter-slice downsampling or intra-slice downsampling can also be used alone to accelerate the acquisition of magnetic resonance images. This specification does not limit this approach. For example, the target region's sampling layers can be determined, and each sampling layer can be designated as the layers to be scanned in the target period. Then, for each layer, the data columns to be acquired can be determined based on intra-slice downsampling rules.

[0087] Step 104: Correct the initial magnetic resonance image sequence of the target period according to the reference period to obtain the corrected magnetic resonance image sequence of the target period, wherein the reference period is the period of obtaining a spatial standard image by using a reference region containing the lesion in advance using magnetic resonance scanning.

[0088] It should be noted that while rapid magnetic resonance imaging (MRI) sequences can often acquire an image in milliseconds, information may be lost during the rapid acquisition process, leading to image distortion and consequently inaccurate temperature maps, affecting the operation. Taking EPI (Extreme Precision Imaging) as an example, EPI can acquire an image in milliseconds, making it a rapid signal acquisition method. Rapid EPI sequences can achieve rapid scanning of 10–20 layers (1–4 seconds). However, because EPI sequences generate signals through continuous gradient alternation, there is no refocusing pulse to correct for inhomogeneities in the main magnetic field and phase information errors. As the EPI factor increases, the accumulated phase error becomes larger, leading to more severe image distortion and artifacts.

[0089] In practical applications, because the patient or phantom position remains unchanged during the scanning of the target region using rapid MRI sequences, the spatial information of tissues within the same scanning plane remains constant, such as blood vessels, tumor boundaries, and cerebral sulci. In other words, the spatial distribution of the target region remains essentially unchanged. Therefore, this unchanging spatial positional information can be used to correct distortions generated during rapid scanning, thus achieving rapid MRI image acquisition without reducing spatial resolution. Specifically, a spatial standard image can be obtained beforehand using a baseline region containing the lesion from an MRI scan. This period can be used as a reference period, and the initial MRI image sequence for the target period can be corrected based on the reference period to obtain the corrected MRI image sequence for the target period.

[0090] The spatial standard imagery is obtained by scanning a reference region based on a spin echo sequence, such as T1, T2, or FLAIR (liquid attenuated inversion echo) images. T1 refers to the spin-lattice relaxation time (also called longitudinal relaxation time), and T2 is the transverse duration. In NMR, T1 and T2 mean that after the radio frequency pulse signal is removed, the excited hydrogen nuclei gradually release energy, their phase and energy levels return to their initial state, and the magnetization vector returns to equilibrium. This process is called relaxation, which is divided into transverse relaxation and longitudinal relaxation, two independent processes. Longitudinal relaxation is the process of high-energy protons releasing energy and returning to a lower energy level; the T1 value is generally used to describe the speed of longitudinal relaxation. Transverse relaxation occurs between protons and is also called spin relaxation; the T2 value is generally used to describe the speed of transverse relaxation.

[0091] In practical applications, before the patient is brought into the operating room and the target region containing the lesion is scanned, a reference region containing the lesion is first scanned to obtain a spatial standard image, providing reference information for subsequent distortion correction. Alternatively, besides the aforementioned method of scanning the reference region containing the lesion once to directly obtain a spatial standard image and plan the surgery, the patient can be scanned once before surgery to obtain preoperative images. Then, when the patient is brought into the operating room, the reference region containing the lesion can be scanned again to obtain a surgical spatial image. The images obtained from the two scans, along with the surgical plan, are registered to obtain the final spatial standard image, thus obtaining the unchanged spatial location information of the target region.

[0092] In practice, both the reference region and the target region contain the lesion. The reference region is the area to be scanned to obtain spatial standard images beforehand, while the target region is the area to be scanned during periodic scanning to obtain the initial magnetic resonance image sequence. For example, it could be the target area and surrounding tissue in the biological tissue to be ablated in a user undergoing treatment. The reference region is larger, while the target region is smaller. In a preferred implementation, the reference region includes the target region, such as the entire head as the reference region, while the target region is the area consisting of the lesion and surrounding tissue.

[0093] In the embodiments of this specification, before scanning the target area containing the lesion using a rapid magnetic resonance imaging sequence, a reference area containing the lesion can be scanned in advance to obtain a spatial standard image without distortion. This provides spatial location information of the target area without distortion, which is then used to correct the initial magnetic resonance image sequence obtained by the scan based on this spatial location information without distortion. This eliminates the distortion generated during the scanning process and ensures the accuracy of the magnetic resonance image sequence.

[0094] In one optional implementation of this embodiment, the initial magnetic resonance image sequence of the target period is corrected according to the reference period to obtain the corrected magnetic resonance image sequence of the target period, including:

[0095] Acquire spatial standard images obtained through pre-scanning;

[0096] The initial magnetic resonance image sequence of the target period is corrected based on the spatial standard image to obtain the corrected magnetic resonance image sequence of the target period.

[0097] It should be noted that before scanning the target region using a rapid magnetic resonance imaging (MRI) sequence to obtain the initial MRI image sequence for the target period, a spin echo sequence can be used to scan and obtain a spatial standard image without spatial distortion. Since the position of the patient or phantom remains unchanged during the scanning process, the spatial information of the tissue in the same scanning plane remains unchanged. Therefore, when correcting the initial MRI image sequence for the target period based on the reference period, the spatial standard image obtained from the reference period scan can be directly used as the basis for correction. The spatial standard image and the initial MRI image sequence for the target period are compared to correct the initial MRI image sequence for the target period, thus obtaining the corrected MRI image sequence for the target period.

[0098] In other words, during the periodic scanning process, the initial magnetic resonance image sequence obtained in each cycle is directly corrected based on the spatial standard image scanned in the reference cycle.

[0099] In one possible implementation, the first tissue location information of the target tissue in the initial magnetic resonance image sequence of the target period can be determined first, and the second tissue location information of the target tissue in the spatial standard image can be determined. Then, based on the first and second tissue location information, a spatial transformation matrix can be calculated. The spatial transformation matrix is ​​used as distortion correction information, and the initial magnetic resonance image sequence of the target period can be corrected according to the distortion correction information to obtain the corrected magnetic resonance image sequence of the target period. In another implementation, the spatial standard image and the initial magnetic resonance image sequence of the target period can be directly compared, and the initial magnetic resonance image sequence of the target period can be corrected to obtain the corrected magnetic resonance image sequence of the target period. At the same time, the distortion correction information is output and stored for later use.

[0100] In the embodiments of this specification, the initial magnetic resonance image sequence obtained in each cycle is directly corrected based on the spatial standard image scanned in the reference cycle, which can eliminate the distortion generated during the scanning process, ensure the accuracy of the magnetic resonance image sequence, and thus ensure the accuracy of the temperature map subsequently constructed.

[0101] In an optional implementation of this embodiment, in addition to the method described above where each cycle is directly corrected based on the reference cycle, each cycle can also be directly corrected based on the distortion correction information of the previous cycle; in this case, correcting the initial magnetic resonance image sequence of the target cycle according to the reference cycle to obtain the corrected magnetic resonance image sequence of the target cycle includes:

[0102] Based on the previous period of the reference period and the target period, obtain the distortion correction information of the previous period;

[0103] The initial magnetic resonance image sequence of the target period is corrected using distortion correction information to obtain the corrected magnetic resonance image sequence of the target period.

[0104] Based on the initial magnetic resonance image sequence and spatial standard image of the target period, the distortion correction information of the target period is determined and stored. The distortion correction information of the target period is used to correct the initial magnetic resonance image sequence of the next period of the target period.

[0105] It should be noted that the distortion correction information of the previous cycle can be obtained first, based on the reference cycle and the previous cycle of the target cycle. Then, this distortion correction information can be directly used to correct the initial MRI image sequence of the target cycle, resulting in the corrected MRI image sequence of the target cycle. After that, the distortion correction information of the target cycle is determined for use in the correction of the next cycle. In other words, each cycle is corrected based on the distortion correction information of the previous cycle.

[0106] As an example, after the reference period, in the second period, since the previous period is the reference period, the initial MRI image sequence of the second period can be corrected based on the spatial standard image of the reference period and the initial MRI image sequence of the second period to obtain the corrected MRI image sequence of the second period. Simultaneously, the distortion correction information of the second period is obtained and stored. Then, in the third period, the distortion correction information of the second period can be directly obtained to correct the initial MRI image sequence of the third period, obtaining the corrected MRI image sequence of the third period. Then, based on the spatial standard image of the reference period and the initial MRI image sequence of the third period, the distortion correction information of the third period can be calculated and stored. Then, in the fourth period, the distortion correction information of the third period can be directly obtained to correct the initial MRI image sequence of the fourth period, and so on. That is, the second cycle is corrected based on the reference cycle (i.e., the first cycle), the third cycle is corrected based on the second cycle, the fourth cycle is corrected based on the third cycle, and so on, until the last cycle is corrected.

[0107] In the embodiments described in this specification, each cycle is corrected based on the distortion correction information of the previous cycle, which can reduce the accumulation of distortion information over multiple cycles and improve the accuracy of correction.

[0108] In one optional implementation of this embodiment, based on the initial magnetic resonance image sequence and spatial standard image of the target period, distortion correction information of the target period is determined and stored, including:

[0109] Determine the first tissue location information of the target tissue in the initial magnetic resonance image sequence of the target period;

[0110] Determine the secondary tissue location information of the target tissue in the spatial standard imagery;

[0111] Based on the first and second tissue location information, a spatial transformation matrix is ​​calculated, and the spatial transformation matrix is ​​used as distortion correction information and stored.

[0112] Specifically, the target tissue is the tissue that remains in the same position in the patient or phantom during the scanning process, such as blood vessels, tumor boundaries, and cerebral sulci.

[0113] It should be noted that image analysis can determine the first tissue location information of the target tissue in the initial magnetic resonance image sequence of the target period, and the second tissue location information of the target tissue in the spatial standard image. Then, a spatial transformation matrix is ​​calculated based on the first and second tissue location information. This spatial transformation matrix represents the distortion correction information between the first and second tissue location information. In this way, the distortion correction information of the target period is determined and stored using the invariant target tissue location information. In the next period, the distortion correction information of the target period can be directly retrieved for correction.

[0114] In an optional implementation of this embodiment, besides the method described above where the initial magnetic resonance image sequence obtained in each cycle is directly corrected based on the spatial standard image scanned in the reference cycle, or where each cycle is directly corrected based on the distortion correction information of the previous cycle, another method can be used to select any cycle as the correction reference cycle to correct the initial magnetic resonance image sequences of each cycle. Specifically, correcting the initial magnetic resonance image sequence of the target cycle according to the reference cycle to obtain the corrected magnetic resonance image sequence of the target cycle includes:

[0115] Choose any period as the correction reference period;

[0116] Constant distortion correction information is obtained based on the reference period and the correction baseline period;

[0117] The initial magnetic resonance image sequence of the target period is corrected using constant distortion correction information to obtain the corrected magnetic resonance image sequence of the target period.

[0118] It should be noted that any period can be selected as the correction reference period. Then, constant distortion correction information is obtained based on the reference period and the correction reference period. This obtained constant distortion correction information is then used to correct the initial MRI image sequence of the target period, resulting in the corrected MRI image sequence of the target period. In other words, the initial MRI image sequence of each period is corrected based on constant distortion correction information, which can be determined based on any selected period. This makes the correction method more flexible and adaptable to different scenario requirements.

[0119] The specific implementation process of obtaining constant distortion correction information based on the reference period and the correction benchmark period can be found in the above-mentioned specific implementation process of determining the distortion correction information of the target period based on the initial magnetic resonance image sequence and spatial standard image of the target period. The embodiments in this specification will not be repeated here.

[0120] In one optional implementation of this embodiment, obtaining constant distortion correction information based on the reference period and the correction baseline period includes:

[0121] If the target period is earlier than the correction reference period, the initial magnetic resonance image sequence of the target period is not corrected, and the next period is continued to be scanned until the target period is the correction reference period, and the initial magnetic resonance image sequence of the correction reference period is obtained by scanning.

[0122] Acquire spatial standard images of the reference period, and obtain constant distortion correction information of the correction reference period based on the spatial standard images and the initial magnetic resonance image sequence of the correction reference period.

[0123] In practical applications, if the target period is earlier than the correction reference period, it means that constant distortion correction information cannot be obtained at present, and the target period cannot be corrected. Therefore, the initial magnetic resonance image sequence of the target period is not corrected at this time, and the next period is continued to be scanned until the target period is the correction reference period. The initial magnetic resonance image sequence of the correction reference period is obtained by scanning. Then, constant distortion correction information can be obtained based on the initial magnetic resonance image sequence of the correction reference period and the spatial standard image of the reference period. Based on this constant distortion correction information, the initial magnetic resonance image sequences of each period after the correction reference period can be corrected.

[0124] It should be noted that since constant distortion correction information cannot be obtained before the correction reference period, and therefore correction cannot be performed, in the embodiments of this specification, the correction reference period is generally selected to be an earlier period, so that constant distortion correction information is obtained in an earlier period before ablation, so as to correct the initial magnetic resonance image sequence of each period.

[0125] It should be noted that the rectified MRI image sequences obtained in each cycle have all undergone distortion correction, eliminating information distortion caused by the rapid scanning process, resulting in high accuracy of the obtained MRI image sequences.

[0126] This specification provides a fast magnetic resonance imaging method that can correct the initial magnetic resonance image sequence of the target period based on the period of a spatial standard image obtained in advance using a reference region containing the lesion through magnetic resonance scanning. In other words, it can correct the magnetic resonance image sequence obtained by fast scanning based on the unchanged spatial position information, eliminate the distortion generated during the fast scanning process, improve the scanning range without reducing the spatial resolution, and reduce the time required for magnetic resonance scanning in one period, thus realizing fast scanning of magnetic resonance image sequences.

[0127] Based on any of the foregoing embodiments, some embodiments of the present invention provide a surgical guidance system. The system includes a host computer equipped with an application program for implementing the aforementioned rapid magnetic resonance imaging method. By executing the rapid magnetic resonance imaging method, the system enables real-time monitoring of the target area using magnetic resonance images, thereby guiding surgical operations such as drainage puncture, biopsy puncture, deep electrode implantation, fiber optic implantation, radiofrequency electrode implantation, cryoablation probes, microwave ablation, hematoma aspiration, and biopsy. The system monitors the process and confirms the results, including confirmation of surgical resection results and structural changes, providing information for surgical guidance. It also includes a display device for matching and displaying the actual intraoperative images with the preoperative plan. Preferably, the display device is a 3D display, which can display the structure in three dimensions, making it more convenient to use.

[0128] In other embodiments, the surgical guidance system also includes a preoperative planning module, or is integrated with existing surgical planning software.

[0129] In some embodiments, the surgical guidance system further includes a registration module and an AR module. The registration module unifies the image space and real space coordinates, while the AR module projects the obtained real-time structure onto the real space for superimposed display, facilitating direct observation of the surgical progress of deep lesions by the physician without switching their line of sight between the surgical site and the screen. The registration module can be an existing surgical navigation device, optical registration device (e.g., NDI), magnetic navigation device, structured light registration, etc., while the AR module can take various forms such as AR glasses. Those skilled in the art will know that various existing technologies can be used to implement AR projection methods and structural devices.

[0130] See Figure 2 , Figure 2 A flowchart of a magnetic resonance-guided ablation imaging method according to an embodiment of this specification is shown, specifically including the following steps 202-204.

[0131] Step 202: Obtain a three-dimensional temperature map of the target period, wherein the temperature map of the target period is obtained based on the magnetic resonance image acquired by the aforementioned fast magnetic resonance imaging method.

[0132] Step 204: Generate an ablation map based on the three-dimensional temperature map of the target period, wherein the ablation map is used to provide information support for the ablation process.

[0133] Ablation can be performed using confocal ultrasound ablation, laser ablation, radiofrequency ablation, etc., to achieve three-dimensional monitoring of the ablation area.

[0134] For example, in current laser ablation surgery, one or more surgical channels can be designed for a specific lesion shape, and then one or more different types of optical fibers can be used for ablation. When using multiple optical fibers to ablate larger lesions, it is still necessary to select the direction of fiber implantation, and then select several cross-sections perpendicular to the direction of fiber implantation for temperature monitoring. It is impossible to monitor all heated tissues simultaneously, so only one optical fiber can be used for ablation at a time, followed by the use of a second optical fiber, resulting in a longer operation time.

[0135] Therefore, this specification proposes three methods for calculating temperature based on magnetic resonance images: one method for magnetic resonance-guided laser ablation, and another method for calculating temperature based on magnetic resonance images. These methods correct the magnetic resonance image sequence obtained through rapid scanning based on invariant spatial position information, eliminating distortions generated during the rapid scanning process. Alternatively, downsampling can be used to achieve scanning, reducing the time required for a single magnetic resonance scan cycle without reducing spatial resolution. This allows for safe ablation of a single optical fiber, or simultaneous ablation of two or more ablation fibers, improving ablation efficiency and shortening ablation and surgical time.

[0136] The magnetic resonance-guided ablation imaging method provided in this specification can be used for the ablation of at least one optical fiber. Before intraoperative magnetic resonance temperature monitoring, at least one optical fiber has been implanted in the target area. Accordingly, the image information of the at least one optical fiber can be observed in the magnetic resonance image sequence (i.e., a set of continuous magnetic resonance images) obtained from one cycle of scanning. After the magnetic resonance device acquires the initial magnetic resonance image sequence obtained from the rapid magnetic resonance imaging sequence scan, the application on the host can receive the above data from the magnetic resonance device for data processing, such as correcting the initial magnetic resonance image sequence to obtain a corrected magnetic resonance image sequence, and further generating a three-dimensional temperature map. Since the final generated temperature map is a three-dimensional temperature map, during the magnetic resonance image acquisition process, magnetic resonance image acquisition can be performed not only in the direction perpendicular to a certain optical fiber, but also from any scanning direction, improving the flexibility of image acquisition and observation, facilitating users to observe the temperature status at various positions and directions, and improving the real-time performance, accuracy, and convenience of temperature monitoring. Furthermore, based on the temperature map, an ablation map can be generated, providing information support for the laser ablation process of at least one optical fiber, and realizing laser ablation.

[0137] In one optional implementation of this embodiment, a temperature map of the target period is obtained based on the magnetic resonance image acquired by the aforementioned fast magnetic resonance imaging method, including:

[0138] A temperature difference map is constructed using the phase difference between a corrected magnetic resonance imaging sequence of the target period and a corrected magnetic resonance imaging sequence of a historical period; where the historical period is any period prior to the target period.

[0139] Based on the temperature difference map and the baseline temperature map, a three-dimensional temperature map of the target period is generated, where the baseline temperature map is the temperature map of the historical period.

[0140] It should be noted that when constructing the temperature map, the phase difference between the two periods of magnetic resonance image sequences needs to be considered. Therefore, when determining the corrected magnetic resonance image sequence of the target period, the corrected magnetic resonance image sequence of the historical period can also be obtained, so as to construct the temperature map by combining the phase difference between the corrected magnetic resonance image sequences of the target period and the historical period.

[0141] The historical period refers to any period before the target period. It can be the period before the target period, the nth period before the target period, or always the first period.

[0142] In practical applications, each magnetic resonance image contains a phase map and an amplitude map. The amplitude map shows tissue structure information, and the phase map can be used to generate a temperature map of that layer. The phase difference between two magnetic resonance images can be used to establish the corresponding temperature map.

[0143] In practice, a temperature difference map can be first established using the phase difference between the corrected magnetic resonance image sequence of the target period and the corrected magnetic resonance image sequence of the historical period. Then, the temperature map of the historical period can be used as the reference temperature map. By combining the temperature difference map and the reference temperature map, the temperature map of the target period can be generated.

[0144] For example, the first cycle can always be used as the historical cycle, and a temperature graph can be built based on the phase difference between the first and second cycles, the phase difference between the first and third cycles, the phase difference between the first and fourth cycles, and so on, to achieve temperature monitoring; or, the cycle preceding the target cycle can be used as the historical cycle, and a temperature graph can be built based on the phase difference between the first and second cycles, the phase difference between the second and third cycles, the phase difference between the third and fourth cycles, and so on, to achieve temperature monitoring.

[0145] It should be noted that the rectified MRI image sequences obtained in each cycle have all undergone distortion correction, eliminating information distortion caused by the rapid scanning process, resulting in high accuracy of the obtained MRI image sequences. Furthermore, the temperature map constructed based on the phase difference between the rectified MRI image sequences of each cycle and the rectified MRI image sequences of historical cycles can improve the image signal-to-noise ratio, ensuring the accuracy of the constructed temperature map and facilitating the observation of temperature changes in three-dimensional space.

[0146] It should be noted that the magnetic resonance-guided ablation imaging method provided in this embodiment acquires magnetic resonance images based on the aforementioned fast magnetic resonance imaging method, eliminating the information distortion generated during the rapid scanning process, improving the image signal-to-noise ratio, and thus establishing a temperature map. This ensures the real-time performance and accuracy of the constructed temperature map. The ablation map generated based on this temperature map can better guide the ablation process and assess the ablation state, thereby providing accurate information support for the laser ablation process of at least one optical fiber.

[0147] In addition to generating an ablation map based on the temperature map of the target period to provide information support for the laser ablation process of at least one fiber, the generated temperature map can also be used to directly guide the ablation process of at least one fiber. The methods for calculating or predicting ablation based on the temperature map are known in the art, such as the Arrhenius equation. Alternatively, the temperature map can be overlaid with the preoperative 3D image and displayed on a display device. This displays the temperature information at each location in the preoperative 3D image (structural image) to guide the ablation process. This display device can be a standalone device or an integrated device with the host computer. Furthermore, the temperature data in the temperature map can be rendered in the preoperative 3D image with corresponding colors to visually represent the temperature state at each location.

[0148] It should be noted that the established temperature and / or ablation maps can provide information support for the laser ablation process of at least one optical fiber. Users can ablate the target area of ​​the target region based on the temperature and / or ablation maps to eliminate lesions. That is, the application on the host computer can also obtain control commands and control the actuator to perform corresponding actions according to the control commands to achieve simultaneous ablation of at least one optical fiber; wherein, the control commands are user-input commands, application default commands, or commands automatically generated by the application.

[0149] Specifically, the application on the host computer can receive instructions from the user through input devices (e.g., mouse, keyboard, touch screen, etc.). After obtaining the control instructions, the application on the host computer controls the actuator to perform the corresponding actions, thereby achieving simultaneous ablation of at least one optical fiber.

[0150] The application on the host computer controls the actuator to perform corresponding actions according to the control instructions. For example, it controls the fiber optic robot to adjust the depth and angle of the fiber so that the fiber can perform precise and conformal ablation; or it controls the laser to adjust the laser power and laser release time; or it controls the peristaltic pump of the cooling component to adjust the circulation rate of the coolant.

[0151] In this embodiment, the application on the host computer obtains control instructions and controls the actuator to perform corresponding actions, accurately achieving simultaneous ablation of at least one optical fiber, avoiding errors caused by human factors, and improving the level of intelligence and surgical precision.

[0152] Furthermore, doctors can directly and manually control the actuators to perform corresponding actions, achieving simultaneous ablation of at least one optical fiber. For example, they can manually adjust the depth and angle of the optical fiber; or directly adjust the output power of the laser; or manually control the adjustment button of the peristaltic pump to regulate the circulation rate of the coolant. In this embodiment, some actuators do not need to communicate with the host computer (i.e., they do not need to be controlled by the host computer); for example, a foot switch can be used to control whether laser light is input to the target area through the optical fiber.

[0153] In a specific implementation, the actuator includes at least one of a fiber optic robot, a laser, and a peristaltic pump. The fiber optic robot is used to adjust the fiber position parameters such as the depth, angle, direction of fiber movement, and speed of fiber movement according to the corresponding control commands. The laser is used to adjust the laser parameters such as the laser power and laser release duration according to the corresponding control commands. The peristaltic pump is used to adjust the circulation rate of the coolant according to the corresponding control commands.

[0154] Fiber optic robots can adjust the depth of the fiber optic cable according to control commands. More specifically, they can adjust the direction of fiber optic movement (axial movement and circumferential rotation), the speed of fiber optic movement, and the stroke (displacement) of fiber optic movement. Fiber optic robots can also adjust the angle of the fiber optic cable, which refers to the angle of rotation of the fiber optic cable around its axis. By adjusting the angle of the fiber optic cable, the light-emitting section of the fiber optic cable can release laser light into the target area in the desired direction, thereby achieving precise and conformal ablation of the target area. The laser can adjust the laser power and laser release duration according to control commands to control the ablation range, ablate the target area as much as possible, and avoid ablation of non-target areas. The peristaltic pump can adjust its rotation speed according to control commands, thereby adjusting the circulation rate (i.e., flow rate) of the coolant.

[0155] Furthermore, the number of each type of actuator is not limited to one. Assuming that m optical fibers are used simultaneously for ablation, for fiber control, one fiber robot can be configured for each fiber; for laser control, one laser can be configured with m optical path switches, each optical path switch controlling the on / off state of one optical fiber path (indirectly adjusting the laser power and laser release time), or n lasers (n≤m) can be configured, each laser controlling the laser power and laser release time of at least one optical fiber, with redundant optical fibers and optical fibers in the same group controlling the on / off state of their respective optical fiber paths through optical path switches; for cooling circulation control, a peristaltic pump can be configured to pump coolant into the cooling pipes of each optical fiber, and a pipe speed control valve can be equipped on each circulation pipe to control the coolant circulation rate of the branch, or p peristaltic pumps (p≤m) can be configured, each peristaltic pump controlling the coolant circulation rate of at least one optical fiber, with redundant optical fibers and optical fibers in the same group sharing a peristaltic pump, and the optical fiber sharing the peristaltic pump equipped with a pipe speed control valve on its cooling circulation branch to adjust the coolant circulation rate of the corresponding branch.

[0156] The magnetic resonance-guided ablation imaging method provided in the embodiments of this specification can monitor the temperature and assess the ablation status from multiple angles for laser ablation with a single optical fiber, thus improving safety. For at least two optical fibers, it is the first time that the laser ablation status of multiple optical fibers can be monitored simultaneously, providing comprehensive and accurate information support for laser ablation with multiple optical fibers at the same time. This makes it convenient for users to perform laser ablation with multiple optical fibers at the same time, improving the accuracy and safety of laser ablation and comprehensively improving surgical efficiency.

[0157] Figure 3 A flowchart of another fast magnetic resonance imaging method provided in one embodiment of this specification is shown, such as... Figure 3 As shown, the specific steps include 302-304.

[0158] Step 302: Use a downsampling strategy to scan the target region containing the lesion to obtain a downsampling sequence of the target period, wherein the target period is any period of periodic scanning of the target region.

[0159] It should be noted that a downsampling strategy can be used to scan the target area containing lesions, thereby increasing the scanning speed of the target area to meet the clinical needs of temperature detection.

[0160] Specifically, the downsampling strategy can be a pre-configured rule that determines which data in the target region to sample and which data to exclude. This downsampling strategy is related to the set scanning algorithm used, which can be a conventional MRI scanning algorithm or a fast scanning algorithm. Furthermore, the set scanning algorithm can be slice-by-slice or column-by-column scanning; that is, the set scanning algorithm can be slice-by-slice.

[0161] In one optional implementation of this embodiment, a downsampling strategy is used to scan the target region containing the lesion to obtain a downsampling sequence of the target period, including:

[0162] Based on the established inter-layer downsampling rules, determine the target layer to be sampled in the target period;

[0163] By setting a scanning algorithm to scan the target layer, a downsampled sequence of the target period is obtained.

[0164] In one optional implementation of this embodiment, the set inter-layer downsampling rule is to sample odd-numbered layers and even-numbered layers at intervals; based on the set inter-layer downsampling rule, the target layer to be sampled in the target period is determined, including:

[0165] Determine the sampling layer of the previous scan cycle;

[0166] When the number of sampling layers is odd, the target layer to be sampled in the target period is determined to be even.

[0167] When the number of sampling layers is even, the target layer to be sampled in the target period is determined to be an odd-numbered layer.

[0168] In one optional implementation of this embodiment, the set inter-layer downsampling rule is as follows: a first strategy is used when the number of layers to be sampled exceeds a layer number threshold, and a second strategy is used when the number of layers does not exceed the layer number threshold; according to the set inter-layer downsampling rule, the target layer to be sampled in the target period is determined, including:

[0169] Determine the number of sampling layers in the target region;

[0170] If the number of layers to be sampled exceeds the layer threshold, the target layer to be sampled in the target period is determined according to the first strategy;

[0171] If the number of layers to be sampled does not exceed the layer threshold, the target layer to be sampled in the target week is determined according to the second strategy.

[0172] In practice, a column-based magnetic resonance imaging sequence may be used. For column-based scanning, the downsampling strategy can employ inter-slice downsampling and / or intra-slice downsampling. Specifically, for column-based scanning, if only inter-slice downsampling is used, the implementation process is the same as the inter-slice downsampling process for slice-based scanning described above, and will not be repeated here.

[0173] In one optional implementation of this embodiment, the downsampling strategy employs inter-slice downsampling and intra-slice downsampling; the downsampling strategy is used to scan the target region containing the lesion to obtain a downsampling sequence of the target period, including:

[0174] Based on the established inter-layer downsampling rules, determine the target layer to be sampled in the target period;

[0175] The data column to be collected for the target period is determined according to the set intra-layer downsampling rules;

[0176] The data columns to be collected in the target layer are scanned to obtain the downsampling sequence of the target period.

[0177] It should be noted that for column-by-column scanning magnetic resonance imaging sequences, since each scan is of one column of data in one layer, both inter-slice downsampling and intra-slice downsampling can be used simultaneously. The specific implementation process of simultaneously using inter-slice downsampling and intra-slice downsampling is similar to the specific implementation process of inter-slice downsampling in the aforementioned embodiments, and will not be repeated here.

[0178] In another optional implementation of this embodiment, for column-scanning magnetic resonance imaging sequence types, the downsampling strategy can also employ only intra-slice downsampling; by setting a scanning algorithm, the downsampling strategy is used to scan the target region containing the lesion to obtain a downsampling sequence of the target period, including:

[0179] The data column to be collected for the target period is determined according to the set intra-layer downsampling rules;

[0180] The data columns to be collected in each layer are scanned to obtain the downsampling sequence of the target period.

[0181] It should be noted that for column-based MRI sequences, since each scan is of one column of data within a layer, in addition to the aforementioned schemes of using only inter-slice downsampling, or using both inter-slice and intra-slice downsampling, it is also possible to omit inter-slice downsampling and use only intra-slice downsampling. That is, the target period's data columns are determined according to predefined intra-slice downsampling rules, and then each layer's data columns are scanned to obtain the downsampled sequence of the target period. In other words, all layers of the target region are scanned, but only a portion of the data columns are scanned per layer, increasing the scan rate without missing any layers.

[0182] Step 304: Reconstruct the complete magnetic resonance image sequence based on the downsampling sequence of the target period to obtain the reconstructed magnetic resonance image sequence of the target period.

[0183] It should be noted that, for the target area (i.e. the ablation area), due to the continuity of tissue in physical space and time, temperature information from adjacent locations can be used to estimate the temperature of the unsampled parts, thereby ensuring the temperature imaging quality of the target area.

[0184] Corresponding to the above-described method embodiments, this specification also provides a magnetic resonance-guided laser ablation system, the system including a host computer. Figure 4This specification illustrates a schematic diagram of the main unit of a magnetic resonance-guided laser ablation system according to one embodiment. Figure 4 As shown, the host includes:

[0185] The first scanning module 402 is configured to periodically scan a target region containing a lesion using a rapid magnetic resonance imaging sequence to obtain an initial magnetic resonance image sequence of the target period, wherein the target period is any period of periodic scanning of the target region.

[0186] The correction module 404 is configured to correct the initial magnetic resonance image sequence of the target period according to the reference period to obtain the corrected magnetic resonance image sequence of the target period, wherein the reference period is the period in which a spatial standard image is obtained in advance using a reference region containing the lesion through magnetic resonance scanning.

[0187] The first generation module 406 is configured to generate a temperature map of the target period using a corrected magnetic resonance image sequence of the target period and a corrected magnetic resonance image sequence of the historical period, wherein the historical period is any period prior to the target period.

[0188] In an optional implementation of this embodiment, the correction module 404 is further configured as follows:

[0189] Acquire spatial standard images obtained through pre-scanning;

[0190] The initial magnetic resonance image sequence of the target period is corrected based on the spatial standard image to obtain the corrected magnetic resonance image sequence of the target period.

[0191] In an optional implementation of this embodiment, the correction module 404 is further configured as follows:

[0192] Based on the previous period of the reference period and the target period, obtain the distortion correction information of the previous period;

[0193] The initial magnetic resonance image sequence of the target period is corrected using distortion correction information to obtain the corrected magnetic resonance image sequence of the target period.

[0194] Based on the initial magnetic resonance image sequence and spatial standard image of the target period, the distortion correction information of the target period is determined and stored. The distortion correction information of the target period is used to correct the initial magnetic resonance image sequence of the next period of the target period.

[0195] In an optional implementation of this embodiment, the correction module 404 is further configured as follows:

[0196] Determine the first tissue location information of the target tissue in the initial magnetic resonance image sequence of the target period;

[0197] Determine the secondary tissue location information of the target tissue in the spatial standard imagery;

[0198] Based on the first and second tissue location information, a spatial transformation matrix is ​​calculated, and the spatial transformation matrix is ​​used as distortion correction information and stored.

[0199] In an optional implementation of this embodiment, the correction module 404 is further configured as follows:

[0200] Choose any period as the correction reference period;

[0201] Constant distortion correction information is obtained based on the reference period and the correction baseline period;

[0202] The initial magnetic resonance image sequence of the target period is corrected using constant distortion correction information to obtain the corrected magnetic resonance image sequence of the target period.

[0203] In an optional implementation of this embodiment, the correction module 404 is further configured as follows:

[0204] If the target period is earlier than the correction reference period, the initial magnetic resonance image sequence of the target period is not corrected, and the next period is continued to be scanned until the target period is the correction reference period, and the initial magnetic resonance image sequence of the correction reference period is obtained by scanning.

[0205] Acquire spatial standard images of the reference period, and obtain constant distortion correction information of the correction reference period based on the spatial standard images and the initial magnetic resonance image sequence of the correction reference period.

[0206] In an optional implementation of this embodiment, the first generation module 406 is further configured as follows:

[0207] A temperature difference map is constructed using the phase difference between the corrected magnetic resonance imaging sequence of the target period and the corrected magnetic resonance imaging sequence of the historical period.

[0208] Based on the temperature difference map and the baseline temperature map, a temperature map for the target period is generated, where the baseline temperature map is a temperature map of the historical period.

[0209] In one optional implementation of this embodiment, the spatial standard image is obtained by scanning a reference region based on a spin echo sequence.

[0210] In one optional implementation of this embodiment, the initial magnetic resonance image sequence of the target period is obtained by scanning the target region based on gradient echo imaging.

[0211] In an optional implementation of this embodiment, the first scanning module 402 is further configured as follows:

[0212] Based on the established inter-layer downsampling rules, determine the target layer to be sampled in the target period;

[0213] The target layer is scanned using a rapid magnetic resonance imaging sequence to obtain an initial magnetic resonance image sequence of the target period.

[0214] In an optional implementation of this embodiment, the set inter-layer downsampling rule is to sample odd-numbered layers and even-numbered layers at intervals; the first scanning module 402 is further configured to:

[0215] Determine the sampling layer of the previous scan cycle;

[0216] If the number of sampling layers in the previous cycle is odd, the target layer to be sampled in the target cycle is determined to be even.

[0217] If the number of sampling layers in the previous cycle is even, the target layer to be sampled in the target cycle is determined to be odd.

[0218] In an optional implementation of this embodiment, the set inter-layer downsampling rule is to use a first strategy when the number of layers to be sampled exceeds a layer threshold, and a second strategy when the number of layers does not exceed the layer threshold; the first scanning module 402 is further configured to:

[0219] Determine the number of sampling layers in the target region;

[0220] If the number of layers to be sampled exceeds the layer threshold, the target layer to be sampled in the target period is determined according to the first strategy;

[0221] If the number of layers to be sampled does not exceed the layer threshold, the target layer to be sampled in the target week is determined according to the second strategy.

[0222] In one optional implementation of this embodiment, the magnetic resonance rapid imaging sequence is scanned column by column; the first scanning module 402 is further configured to:

[0223] The data column to be collected for the target period is determined according to the set intra-layer downsampling rules;

[0224] The initial magnetic resonance image sequence of the target period is obtained by scanning the data column to be collected in the target layer using a rapid magnetic resonance imaging sequence.

[0225] The host of the magnetic resonance-guided laser ablation system provided in this specification can correct the initial magnetic resonance image sequence of the target period based on the period of obtaining a spatial standard image of a reference area containing the lesion using magnetic resonance scanning. That is, it can correct the magnetic resonance image sequence obtained by rapid scanning based on the unchanged spatial position information, eliminate the distortion generated during the rapid scanning process, improve the scanning range without reducing the spatial resolution, and reduce the time required for magnetic resonance scanning in one period. It realizes rapid scanning of 3D magnetic resonance image sequences. During magnetic resonance scanning, images can be acquired from any scanning direction, which improves the flexibility of image acquisition and observation, makes it easier for users to observe the tissue state at various positions and directions, and improves the real-time performance, accuracy and convenience of magnetic resonance imaging.

[0226] The above is a schematic representation of the host device of a magnetic resonance-guided laser ablation system according to this embodiment. It should be noted that the technical solution of the host device of this magnetic resonance-guided laser ablation system belongs to the same concept as the technical solution of the aforementioned fast magnetic resonance imaging method. Details not described in detail in the technical solution of the host device of the magnetic resonance-guided laser ablation system can be found in the description of the technical solution of the aforementioned fast magnetic resonance imaging method.

[0227] Corresponding to the above-described method embodiments, this specification also provides a host unit in another magnetic resonance-guided laser ablation system. Figure 5 A schematic diagram of the host unit in another magnetic resonance-guided laser ablation system provided in one embodiment of this specification is shown. Figure 5 As shown, the host includes:

[0228] The acquisition module 502 is configured to acquire a temperature map of a target period, wherein the temperature map of the target period is obtained by the fast magnetic resonance imaging method described above.

[0229] The second generation module 504 is configured to generate an ablation map based on the temperature map of the target period, wherein the ablation map is used to provide information support for the laser ablation process of at least one optical fiber.

[0230] This specification provides another host unit in a magnetic resonance-guided laser ablation system. For laser ablation with a single fiber, the system can monitor the temperature from multiple angles and assess the ablation status, improving safety. For at least two fibers, this system enables simultaneous monitoring of the laser ablation status of multiple fibers for the first time, providing comprehensive and accurate information support for simultaneous laser ablation with multiple fibers. This facilitates simultaneous laser ablation with multiple fibers, improving the accuracy and safety of laser ablation and comprehensively enhancing surgical efficiency.

[0231] The above is a schematic representation of the host unit in a magnetic resonance-guided laser ablation system according to this embodiment. It should be noted that the technical solution of the host unit in this magnetic resonance-guided laser ablation system belongs to the same concept as the technical solution of the aforementioned fast magnetic resonance imaging method. Details not described in detail in the technical solution of the host unit in the magnetic resonance-guided laser ablation system can be found in the description of the technical solution of the aforementioned fast magnetic resonance imaging method.

[0232] Corresponding to the above-described method embodiments, this specification also provides another magnetic resonance-guided laser ablation system, the system including a host computer, Figure 6 A schematic diagram of the main unit of a magnetic resonance-guided laser ablation system according to one embodiment of this specification is shown. Figure 6 As shown, the host includes:

[0233] The second scanning module 602 is configured to scan the target region containing lesions using a downsampling strategy to obtain a downsampling sequence of the target period, wherein the target period is any period of periodic scanning of the target region, the downsampling strategy is determined based on a set scanning algorithm, and the downsampling sequence of the target period contains image information of at least one optical fiber.

[0234] The reconstruction module 604 is configured to reconstruct a complete magnetic resonance image sequence based on the downsampling sequence of the target period, thereby obtaining a reconstructed magnetic resonance image sequence of the target period.

[0235] The third generation module 606 is configured to acquire the reconstructed magnetic resonance image sequence of the historical period, and generate a temperature map of the target period based on the reconstructed magnetic resonance image sequence of the target period and the reconstructed magnetic resonance image sequence of the historical period, wherein the historical period is any period before the target period, and the temperature map is used to provide information support for the laser ablation process of at least one optical fiber.

[0236] In one optional implementation of this embodiment, the downsampling strategy is inter-layer downsampling; the second scanning module 602 is further configured as follows:

[0237] Based on the established inter-layer downsampling rules, determine the target layer to be sampled in the target period;

[0238] The target layer is scanned to obtain the downsampled sequence of the target period.

[0239] In an optional implementation of this embodiment, the set inter-layer downsampling rule is to sample odd-numbered layers and even-numbered layers at intervals; the second scanning module 602 is further configured to:

[0240] Determine the sampling layer of the previous scan cycle;

[0241] When the number of sampling layers is odd, the target layer to be sampled in the target period is determined to be even.

[0242] When the number of sampling layers is even, the target layer to be sampled in the target period is determined to be an odd-numbered layer.

[0243] In an optional implementation of this embodiment, the set inter-layer downsampling rule is to use a first strategy when the number of layers to be sampled exceeds a layer threshold, and a second strategy when the number of layers does not exceed the layer threshold; the second scanning module 602 is further configured to:

[0244] Determine the number of sampling layers in the target region;

[0245] If the number of layers to be sampled exceeds the layer threshold, the target layer to be sampled in the target period is determined according to the first strategy;

[0246] If the number of layers to be sampled does not exceed the layer threshold, the target layer to be sampled in the target week is determined according to the second strategy.

[0247] In one optional implementation of this embodiment, the downsampling strategy is inter-layer downsampling and intra-layer downsampling; the second scanning module 602 is further configured as follows:

[0248] Based on the established inter-layer downsampling rules, determine the target layer to be sampled in the target period;

[0249] The data column to be collected for the target period is determined according to the set intra-layer downsampling rules;

[0250] The data columns to be collected in the target layer are scanned to obtain the downsampling sequence of the target period.

[0251] In one optional implementation of this embodiment, the downsampling strategy is intra-layer downsampling; the second scanning module 602 is further configured as follows:

[0252] The data column to be collected for the target period is determined according to the set intra-layer downsampling rules;

[0253] The data columns to be collected in each layer are scanned to obtain the downsampling sequence of the target period.

[0254] The host of the magnetic resonance-guided laser ablation system provided in this specification has spatial redundancy between frames because the target area remains unchanged. A downsampling acceleration method can be used to speed up the acquisition of magnetic resonance images, scanning only a portion of the data in each cycle, greatly accelerating the acquisition of magnetic resonance images. Utilizing the invariance of spatial information in the target area and the continuity of temperature in physical space and time, complete magnetic resonance image information can be reconstructed, thus ensuring the quality of the acquired images. High spatiotemporal resolution and wide-range temperature imaging are achieved without changing image quality or scanning time, thereby enabling rapid scanning of 3D magnetic resonance image sequences. This allows magnetic resonance-based temperature measurement and ablation calculations to meet clinical needs, enabling full-volume temperature monitoring of the target area. It can acquire magnetic resonance images not only perpendicular to a certain optical fiber but also from any scanning direction, improving the flexibility of image acquisition and observation. This facilitates users in observing the temperature status at various locations and directions, assessing the ablation status, and improving the accuracy and convenience of temperature monitoring. Therefore, for laser ablation using a single fiber, temperature can be monitored from multiple angles and the ablation status can be assessed, improving safety. For at least two fibers, this is the first time that the laser ablation status of multiple fibers can be monitored simultaneously, providing comprehensive and accurate information support for performing laser ablation with multiple fibers at the same time. This makes it convenient for users to perform laser ablation with multiple fibers simultaneously, improving the accuracy and safety of laser ablation and comprehensively enhancing surgical efficiency.

[0255] The above is a schematic representation of the host device of a magnetic resonance-guided laser ablation system according to this embodiment. It should be noted that the technical solution of the host device of this magnetic resonance-guided laser ablation system belongs to the same concept as the technical solution of the aforementioned fast magnetic resonance imaging method. Details not described in detail in the technical solution of the host device of the magnetic resonance-guided laser ablation system can be found in the description of the technical solution of the aforementioned fast magnetic resonance imaging method.

[0256] Corresponding to the above-described method embodiments, this specification also provides a magnetic resonance-guided laser ablation system. Figure 7 A schematic diagram of a magnetic resonance-guided laser ablation system according to one embodiment of this specification is shown. Figure 7 As shown, the magnetic resonance-guided laser ablation system 700 includes a host 710, which is equipped with an application program for implementing the aforementioned rapid magnetic resonance imaging method.

[0257] In one optional implementation of this embodiment, Figure 8 This is a schematic diagram of another magnetic resonance-guided laser ablation system provided in one embodiment of this specification, as shown in Figure 9. Figure 8As shown, the magnetic resonance-guided laser ablation system 800 includes a host 810, a magnetic resonance device 820, a laser ablation component 830, and a cooling component 840. The laser ablation component 830 includes a fiber optic robot and a laser, and the cooling component 840 includes a peristaltic pump.

[0258] Specifically, the magnetic resonance imaging (MRI) device 820 is used to acquire MRI images of the patient based on the set scanning parameters and the scanning parameters sent by the host 810, and send them to the host 810 for processing, providing information guidance for the multi-fiber laser ablation process; the laser ablation component 830 is used to execute specific ablation actions according to the control instructions of the host 810 and / or the manual operation of the doctor. The laser ablation component 830 may include devices such as a fiber optic robot, a laser, and a fiber optic sleeve. The laser is used to generate laser light and guide the laser light into the target area through an optical fiber. The fiber optic robot is used to adjust the depth, angle, direction of movement, and speed of the optical fiber; the cooling component 840 is used to cool the optical fiber implanted in the target area according to the control instructions of the host 810 and / or the manual operation of the doctor to avoid damage to normal tissue. The cooling component 840 may include devices such as a cooling liquid container, a cooling liquid recovery container, a cooling circulation pipeline, and a peristaltic pump 8401.

[0259] In one optional embodiment of this example, the application on the host 810 is also used to control at least one of the fiber optic robot, laser, and peristaltic pump, and execute the corresponding actions of the control commands to achieve simultaneous ablation of at least one fiber optic cable.

[0260] Fiber optic robot, used to adjust the fiber position parameters of the optical fiber according to corresponding control commands;

[0261] A laser, used to adjust laser parameters according to corresponding control commands;

[0262] A peristaltic pump is used to adjust the circulation rate of the coolant according to corresponding control commands.

[0263] It should be noted that fiber optic position parameters may include the fiber's depth, angle, direction of fiber movement, and speed of fiber movement; laser parameters may include laser power and laser release duration.

[0264] This specification provides an embodiment of a magnetic resonance-guided laser ablation system. The system includes a host computer. An application program on the host computer can correct the magnetic resonance image sequence obtained through rapid scanning based on invariant spatial location information. This eliminates distortions generated during rapid scanning, increases the scanning range without reducing spatial resolution, and reduces the time required for a single magnetic resonance scan cycle. Alternatively, the application program on the host computer can employ a downsampling acceleration method to speed up the acquisition of magnetic resonance images. Each cycle scans only a portion of the data, significantly accelerating the acquisition of magnetic resonance images. By utilizing the invariance of spatial information in the target area and the continuity of temperature in physical space and time, complete magnetic resonance image information can be reconstructed, thereby ensuring the quality of the acquired images. This achieves high spatiotemporal resolution and wide-range temperature imaging without altering image quality or scanning time.

[0265] This technology enables rapid scanning of 3D magnetic resonance imaging sequences, allowing magnetic resonance-based temperature measurement and ablation calculations to meet clinical needs. It enables full-volume temperature monitoring of the target area, and allows for image acquisition not only perpendicular to a single fiber but also from any scanning direction, enhancing the flexibility of image acquisition and observation. This facilitates user observation of temperature status at various locations and directions, assesses the ablation status, and improves the accuracy and convenience of temperature monitoring. Therefore, for laser ablation using a single fiber, temperature can be monitored from multiple angles to assess the ablation status, improving safety. For at least two fibers, this technology achieves simultaneous monitoring of the laser ablation status of multiple fibers for the first time, providing comprehensive and accurate information support for simultaneous laser ablation using multiple fibers. This facilitates simultaneous laser ablation using multiple fibers, improving the accuracy and safety of laser ablation and comprehensively enhancing surgical efficiency.

[0266] The above is a schematic scheme of a magnetic resonance-guided laser ablation system according to this embodiment. It should be noted that the technical solution of this magnetic resonance-guided laser ablation system belongs to the same concept as the technical solution of the above-described fast magnetic resonance imaging method. For details not described in detail in the technical solution of the magnetic resonance-guided laser ablation system, please refer to the description of the technical solution of the above-described fast magnetic resonance imaging method.

[0267] An embodiment of this specification also provides a computer-readable storage medium disposed in the host of a magnetic resonance-guided laser ablation system, which stores computer-executable instructions that, when executed by a processor, implement the aforementioned fast magnetic resonance imaging method.

[0268] The above is an illustrative scheme of a computer-readable storage medium according to this embodiment. It should be noted that the technical solution of this storage medium belongs to the same concept as the technical solution of the above-described fast magnetic resonance imaging method. For details not described in detail in the technical solution of the storage medium, please refer to the description of the technical solution of the above-described fast magnetic resonance imaging method.

[0269] An embodiment of this specification also provides a computer program, wherein when the computer program is executed in a computer, it causes the computer to perform the steps of the above-described fast magnetic resonance imaging method.

[0270] The above is an illustrative example of a computer program according to this embodiment. It should be noted that the technical solution of this computer program belongs to the same concept as the technical solution of the aforementioned fast magnetic resonance imaging method. Details not described in detail in the computer program's technical solution can be found in the description of the technical solution of the aforementioned fast magnetic resonance imaging method.

[0271] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0272] Computer instructions include computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. Computer-readable media can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in computer-readable media can be appropriately added or removed according to the requirements of patent practice. For example, in some regions, according to patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0273] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments in this specification are not limited to the described order of actions, because according to the embodiments in this specification, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in this specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to the embodiments in this specification.

[0274] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0275] The preferred embodiments disclosed above are merely illustrative of this specification. The optional embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the embodiments described in this specification. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the embodiments, thereby enabling those skilled in the art to better understand and utilize this specification. This specification is limited only by the claims and their full scope and equivalents.

Claims

1. A method of fast magnetic resonance imaging, characterized by, The method includes: An initial magnetic resonance image sequence containing a lesion is obtained by periodically scanning a target region using a rapid magnetic resonance imaging sequence, wherein the target period is any period of periodic scanning of the target region; The initial magnetic resonance image sequence of the target period is corrected according to the reference period to obtain the corrected magnetic resonance image sequence of the target period, wherein the reference period is the period in which a spatial standard image is obtained in advance using a magnetic resonance scan of a reference region containing the lesion.

2. The method of claim 1, wherein, The step of correcting the initial magnetic resonance image sequence of the target period according to the reference period to obtain the corrected magnetic resonance image sequence of the target period includes: Acquire spatial standard images obtained through pre-scanning; The initial magnetic resonance image sequence of the target period is corrected based on the spatial standard image to obtain the corrected magnetic resonance image sequence of the target period.

3. The method of claim 1, wherein, The step of correcting the initial magnetic resonance image sequence of the target period according to the reference period to obtain the corrected magnetic resonance image sequence of the target period includes: Based on the reference period and the previous period of the target period, obtain the distortion correction information of the previous period; The distortion correction information is used to correct the initial magnetic resonance image sequence of the target period to obtain the corrected magnetic resonance image sequence of the target period. Based on the initial magnetic resonance image sequence of the target period and the spatial standard image, distortion correction information of the target period is determined and stored, wherein the distortion correction information of the target period is used to correct the initial magnetic resonance image sequence of the next period of the target period.

4. The method of claim 3, wherein, The process of determining and storing distortion correction information for the target period based on the initial magnetic resonance image sequence and the spatial standard image includes: Determine the first tissue location information of the target tissue in the initial magnetic resonance image sequence of the target period; Determine the second tissue location information of the target tissue in the spatial standard image; Based on the first tissue location information and the second tissue location information, a spatial transformation matrix is ​​calculated, and the spatial transformation matrix is ​​used as the distortion correction information and stored.

5. The method of claim 1, wherein, The step of correcting the initial magnetic resonance image sequence of the target period according to the reference period to obtain the corrected magnetic resonance image sequence of the target period includes: Choose any period as the correction reference period; Constant distortion correction information is obtained based on the reference period and the correction baseline period; The constant distortion correction information is used to correct the initial magnetic resonance image sequence of the target period to obtain the corrected magnetic resonance image sequence of the target period.

6. The method of claim 5, wherein, The step of obtaining constant distortion correction information based on the reference period and the correction baseline period includes: If the target period is earlier than the correction reference period, the initial magnetic resonance image sequence of the target period is not corrected, and the next period is continued to be scanned until the target period is the correction reference period, and the initial magnetic resonance image sequence of the correction reference period is obtained by scanning. Acquire a spatial standard image of the reference period, and obtain constant distortion correction information of the correction reference period based on the spatial standard image and the initial magnetic resonance image sequence of the correction reference period.

7. The method according to any one of claims 1 to 6, characterized in that, The spatial standard image is obtained by scanning the reference region based on a spin echo sequence.

8. The method according to any one of claims 1 to 6, characterized in that, The initial magnetic resonance image sequence of the target period is obtained by scanning the target region based on gradient echo imaging.

9. A method of fast magnetic resonance imaging, characterized by, The method includes: A downsampling strategy is used to scan the target region containing lesions to obtain a downsampling sequence of the target period, wherein the target period is any period of periodic scanning of the target region; A complete magnetic resonance image sequence is reconstructed based on the downsampling sequence of the target period to obtain the reconstructed magnetic resonance image sequence of the target period.

10. The method of claim 9, wherein, The step of scanning the target region containing lesions using a downsampling strategy to obtain a downsampling sequence of the target period includes: Based on the established inter-layer downsampling rules, the target layer to be sampled in the target period is determined; The target layer is scanned using the defined scanning algorithm to obtain the downsampled sequence of the target period.

11. The method of claim 10, wherein, The established inter-layer downsampling rule is to sample odd-numbered layers and even-numbered layers at intervals. The step of determining the target layer to be sampled in the target period according to the set inter-layer downsampling rules includes: Determine the sampling layer of the previous scan cycle; In the case that the number of sampling layers is odd, the target layer to be sampled in the target period is determined to be an even number of layers; If the number of sampling layers is even, the target layer to be sampled in the target period is determined to be an odd-numbered layer.

12. The method of claim 10, wherein, The set inter-layer downsampling rule is to use the first strategy when the number of layers to be sampled exceeds the layer number threshold, and the second strategy when the number of layers does not exceed the layer number threshold; The step of determining the target layer to be sampled in the target period according to the set inter-layer downsampling rules includes: Determine the number of sampling layers in the target region; If the number of layers to be sampled exceeds the layer threshold, the target layer to be sampled in the target period is determined according to the first strategy; If the number of layers to be sampled does not exceed the layer threshold, the target layer to be sampled in the target period is determined according to the second strategy.

13. The method of claim 9, wherein, The step of scanning the target region containing lesions using a downsampling strategy to obtain a downsampling sequence of the target period includes: Based on the established inter-layer downsampling rules, the target layer to be sampled in the target period is determined; The data column to be collected for the target period is determined according to the set intra-layer downsampling rules; The target data column is scanned in the target layer using the defined scanning algorithm to obtain the downsampling sequence of the target period.

14. The method of claim 9, wherein, The step of scanning the target region containing lesions using a downsampling strategy to obtain a downsampling sequence of the target period includes: The data column to be collected for the target period is determined according to the set intra-layer downsampling rules; The set scanning algorithm is used to scan the data columns to be collected in each layer to obtain the downsampling sequence of the target period.

15. A surgical guidance system, characterized by, Includes a host computer, the host computer being equipped with an application program for implementing the fast magnetic resonance imaging method according to any one of claims 1-8 or 9-14, and providing guidance information for surgery by executing the fast magnetic resonance imaging method.

16. The surgical guidance system according to claim 15, characterized in that, It also includes AR devices for displaying intraoperative images in real space.

Images