Lung tumor magnetic resonance perfusion imaging analysis method, device, equipment and storage medium

Abstract

This invention provides a method, apparatus, device, and storage medium for analyzing lung tumor perfusion imaging using magnetic resonance imaging (MRI), relating to the field of medical image analysis technology. The method includes: acquiring diaphragmatic motion signals of the subject while the subject maintains free breathing via diaphragmatic navigation; determining respiratory gating conditions based on the diaphragmatic motion signals and generating a prospective motion compensation control signal; performing a three-dimensional dynamic contrast-enhanced MRI scan under the control of the prospective motion compensation control signal, using the lung tumor region as the scanning area, to obtain a three-dimensional dynamic contrast-enhanced MRI image sequence; performing perfusion quantitative analysis on the three-dimensional dynamic contrast-enhanced MRI image sequence to obtain the time-signal intensity curve and perfusion quantitative parameters of the lung tumor region, and generating perfusion change information. This solution improves the accuracy of quantitative parameters through prospective motion compensation technology, achieving safe, accurate, and repeatable quantitative assessment of lung tumor perfusion imaging.

Description

Technical Field

[0001] This invention relates to the field of medical image analysis technology, specifically to a method, apparatus, equipment, and storage medium for analyzing magnetic resonance perfusion imaging of lung tumors. Background Technology

[0002] Lung cancer is a malignant tumor with a high incidence and mortality rate worldwide. Currently, clinical treatment mainly relies on computed tomography (CT) or positron emission tomography (PET) for lung tumor imaging analysis. However, these technologies involve ionizing radiation, and for patients requiring long-term, frequent follow-up examinations, the cumulative radiation dose poses a health risk. Furthermore, iodine-containing contrast agents may also cause adverse reactions.

[0003] Magnetic resonance imaging (MRI) has emerged as a promising alternative due to its lack of ionizing radiation and excellent soft tissue resolution. However, conventional lung MRI is extremely sensitive to respiratory motion, typically requiring patients to repeatedly hold their breath during the scan. This is difficult to achieve for lung cancer patients with poor respiratory function or poor compliance, leading to decreased image quality. To address the respiratory motion artifact problem, some existing techniques have proposed MRI methods for free breathing, such as retrospective motion correction using image information after data acquisition. However, these retrospective correction methods have limited effectiveness for the complex and irregular respiratory motions of the lungs, especially in perfusion imaging requiring high-precision dynamic contrast signals, making it difficult to guarantee the stability and accuracy of image quality and quantitative parameters. Therefore, current technology still lacks a solution that can effectively overcome lung motion interference under free breathing conditions and provide accurate functional quantitative assessment of lung tumors. Summary of the Invention

[0004] This invention provides a method, apparatus, device, and storage medium for analyzing lung tumors using magnetic resonance perfusion imaging.

[0005] According to a first aspect of the present invention, a method for analyzing magnetic resonance perfusion imaging of lung tumors is provided, comprising: acquiring diaphragmatic motion signals of the subject by diaphragmatic navigation while the subject maintains free breathing; determining respiratory gating conditions based on the diaphragmatic motion signals, and generating a prospective motion compensation control signal according to the respiratory gating conditions; the prospective motion compensation control signal is used to ensure that magnetic resonance data acquisition is performed when the respiratory gating conditions are met; performing a three-dimensional dynamic contrast-enhanced magnetic resonance scan under the control of the prospective motion compensation control signal, with the region where the lung tumor is located as the scanning region, to obtain a three-dimensional dynamic contrast-enhanced magnetic resonance image sequence including plain scan phases and multiple enhancement phases; performing perfusion quantitative analysis on the three-dimensional dynamic contrast-enhanced magnetic resonance image sequence to obtain the time-signal intensity curve and perfusion quantitative parameters of the lung tumor region, and generating perfusion change information based on reference perfusion quantitative parameters and perfusion quantitative parameters; the reference perfusion quantitative parameters are historical perfusion quantitative parameters corresponding to the subject.

[0006] Optionally, while the subject is breathing freely, the diaphragm motion signal of the subject is acquired through diaphragm navigation, including: determining the diaphragm fornix region corresponding to the subject based on the magnetic resonance imaging (MRI) image corresponding to the subject, and setting the diaphragm navigation sampling area based on the diaphragm fornix region; acquiring the diaphragm position signal through the diaphragm navigation sampling area during the subject's free breathing process; and generating the diaphragm motion signal based on the diaphragm position signal.

[0007] Optionally, respiratory gating conditions are determined based on diaphragmatic motion signals, and prospective motion compensation control signals are generated based on the respiratory gating conditions, including: determining the end-expiratory phase of the subject's respiratory cycle based on diaphragmatic motion signals, and setting a navigation reception window based on the end-expiratory phase; determining the current diaphragmatic position based on diaphragmatic motion signals; generating a prospective motion compensation control signal to characterize allowing magnetic resonance data acquisition when the current diaphragmatic position is within the navigation reception window; and generating a prospective motion compensation control signal to characterize pausing or inhibiting magnetic resonance data acquisition when the current diaphragmatic position is outside the navigation reception window.

[0008] Optionally, the lung tumor magnetic resonance perfusion imaging analysis method further includes: real-time monitoring of diaphragmatic motion signals during the execution of three-dimensional dynamic contrast-enhanced magnetic resonance scanning; adjusting the position and / or width of the navigation receiving window according to the diaphragmatic motion state of the subject during the examination; and updating the respiratory gating conditions according to the adjusted navigation receiving window.

[0009] Optionally, using the region where the lung tumor is located as the scanning area, a three-dimensional dynamic contrast-enhanced magnetic resonance (MRI) scan is performed under the control of a prospective motion compensation control signal to obtain a three-dimensional dynamic contrast-enhanced MRI image sequence including plain scan phases and multiple contrast-enhanced phases. This includes: performing plain scan phase acquisition with the region where the lung tumor is located as the scanning coverage area to obtain plain scan phase images; after the subject begins administration of the MRI contrast agent, performing multiple contrast-enhanced phase acquisitions under prospective motion compensation control of diaphragmatic navigation combined with respiratory gating to obtain a contrast-enhanced phase sequence; and constructing a three-dimensional dynamic contrast-enhanced MRI image sequence based on the acquisition time sequence using the plain scan phase images and the contrast-enhanced phase sequence.

[0010] Optionally, after the subject begins administration of the magnetic resonance contrast agent, multiple enhancement phase acquisitions are performed under prospective motion compensation control combining diaphragmatic navigation and respiratory gating to obtain an enhancement phase sequence, including: acquiring the time information of the start of magnetic resonance contrast agent administration; coordinating the start time of enhancement phase acquisition based on the time information; and continuously performing prospective data acquisition control based on diaphragmatic navigation and respiratory gating during multiple enhancement phase acquisitions to obtain an enhancement phase sequence.

[0011] Optionally, perfusion quantitative analysis is performed on the three-dimensional dynamic contrast-enhanced magnetic resonance image sequence to obtain the time-signal intensity curve and perfusion quantitative parameters of the lung tumor region. Based on the reference perfusion quantitative parameters and the perfusion quantitative parameters, perfusion change information is generated, including: performing motion correction and baseline correction sequentially on the three-dimensional dynamic contrast-enhanced magnetic resonance image sequence to obtain the corrected image sequence; determining the region of interest in the lung tumor region based on the corrected image sequence and extracting the signal intensity change information of the region of interest in different phases; generating a time-signal intensity curve based on the signal intensity change information and the actual acquisition time of each phase, and calculating the perfusion quantitative parameters based on the time-signal intensity curve; the perfusion quantitative parameters include at least one of the following: volume transport constant, initial area under the curve, maximum enhancement slope, and contrast agent enhancement ratio; comparing the perfusion quantitative parameters with the reference perfusion quantitative parameters to generate perfusion change information.

[0012] According to a second aspect of the present invention, a lung tumor magnetic resonance perfusion imaging analysis device is provided, comprising: a diaphragm navigation module for acquiring diaphragm motion signals of the subject while the subject maintains free breathing; a signal generation module for determining respiratory gating conditions based on the diaphragm motion signals and generating a prospective motion compensation control signal according to the respiratory gating conditions; the prospective motion compensation control signal is used to enable magnetic resonance data acquisition to be performed when the respiratory gating conditions are met; a scan control module for performing three-dimensional dynamic contrast-enhanced magnetic resonance scanning with the lung tumor region as the scan region under the control of the prospective motion compensation control signal to obtain a three-dimensional dynamic contrast-enhanced magnetic resonance image sequence including plain scan phases and multiple enhancement phases; and an image analysis module for performing perfusion quantitative analysis on the three-dimensional dynamic contrast-enhanced magnetic resonance image sequence to obtain the time-signal intensity curve and perfusion quantitative parameters of the lung tumor region, and generating perfusion change information based on reference perfusion quantitative parameters and perfusion quantitative parameters; the reference perfusion quantitative parameters are historical perfusion quantitative parameters corresponding to the subject.

[0013] According to a third aspect of the present invention, an electronic device is provided, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform any of the methods in the embodiments of the present invention.

[0014] According to a fourth aspect of the invention, a non-transitory computer-readable storage medium is provided storing computer instructions, wherein the computer instructions are used to cause the computer to perform any of the methods according to embodiments of the invention.

[0015] The solution of this invention utilizes magnetic resonance imaging (MRI) technology, completely avoiding the ionizing radiation risks of CT and PET-CT, and can be safely used for lung cancer patients requiring long-term, multiple follow-ups. By employing diaphragmatic navigation and respiratory gating technology, data acquisition is achieved during the patient's free breathing state, eliminating the need for breath-holding and significantly reducing the patient's examination burden. This is particularly suitable for patients with impaired respiratory function or poor cooperation, significantly expanding the applicable population. Simultaneously, through prospective motion compensation control, respiratory motion artifacts are actively suppressed, ensuring the quality and consistency of dynamic image sequences. Based on this, by calculating perfusion quantitative parameters such as volume transport constant and initial area under the curve, changes in tumor microcirculation hemodynamics can be objectively and accurately reflected. Furthermore, the use of three-dimensional dynamic contrast-enhanced MRI scanning can acquire high-resolution three-dimensional image data, supporting reconstruction and analysis in any plane, providing physicians with more comprehensive lesion information and compensating for the shortcomings of traditional two-dimensional breath-hold imaging in terms of spatial coverage and reconstruction flexibility.

[0016] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0017] The accompanying drawings are provided for a better understanding of this solution and do not constitute a limitation of the invention. Wherein: Figure 1 This is a schematic flowchart of a lung tumor magnetic resonance perfusion imaging analysis method according to an embodiment of the present invention; Figure 2 This is a first comparison image of MRI perfusion images and enhanced CT images according to an embodiment of the present invention; Figure 3 This is a second comparison image of MRI perfusion images and enhanced CT images according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of a lung tumor magnetic resonance perfusion imaging analysis device according to an embodiment of the present invention; Figure 5 This is a structural diagram of an electronic device used to implement the lung tumor magnetic resonance perfusion imaging analysis method according to embodiments of the present invention. Detailed Implementation

[0018] The following description, in conjunction with the accompanying drawings, illustrates exemplary embodiments of the present invention, including various details to aid understanding. These details should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope of the invention. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0019] In this document, the term "and / or" merely describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. The term "at least one" in this document indicates any combination of at least two of a plurality of elements. For example, including at least one of A, B, and C can mean including any one or more elements selected from the set consisting of A, B, and C. The terms "first" and "second" in this document refer to and distinguish between multiple similar technical terms, not to restrict the order or to limit there to only two. For example, "first feature" and "second feature" refer to two categories / two features; the first feature can be one or more, and the second feature can also be one or more.

[0020] Furthermore, to better illustrate the present invention, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that the present invention can be practiced without certain specific details. In some instances, methods, means, elements, and circuits well known to those skilled in the art have not been described in detail in order to highlight the spirit of the invention.

[0021] Before introducing the technical solutions of the embodiments of the present invention, the technical terms that may be used in the present invention will be further explained: Proactive motion compensation is a technique that actively suppresses motion artifacts, as opposed to retrospective correction. It monitors motion signals (such as breathing) in real time during data acquisition and only triggers data acquisition when the body is in a preset static or near-static state, thus ensuring data consistency from the outset.

[0022] Diaphragmatic navigation is a technique used in magnetic resonance imaging (MRI) scans to track respiratory movements. It involves placing a fast, low-resolution sampling probe in the diaphragm (usually the right diaphragm top) to acquire real-time signals of diaphragmatic positional changes caused by breathing.

[0023] Respiratory gating: Based on the respiratory signals acquired through diaphragmatic navigation, an acceptable range of diaphragmatic positions (i.e., the navigation reception window) is set, and magnetic resonance data acquisition is only allowed when the diaphragm position falls within this range. In this invention, gating specifically refers to gating at the end of the expiratory phase.

[0024] Perfusion quantification parameters: A series of values ​​calculated through pharmacokinetic model analysis of dynamic enhanced magnetic resonance imaging data. These parameters quantify physiological characteristics of tissue microcirculation, such as blood flow, blood volume, and vascular permeability. Examples include volume transport constant, initial area under the curve, extracellular space volume fraction, and plasma volume fraction.

[0025] Region of Interest (ROI): This refers to a specific area on a medical image that is delineated for quantitative analysis.

[0026] Time-signal intensity curve: A curve plotted with time on the x-axis and the average signal intensity within a specific ROI on the y-axis. This curve visually demonstrates the complete process of tissue signal intensity change over time after contrast agent injection and is the basis for calculating perfusion quantitative parameters.

[0027] Existing technologies for lung tumor imaging analysis pose risks of ionizing radiation and lack a magnetic resonance imaging method that can effectively overcome lung motion interference while the patient is breathing freely, and achieve accurate and repeatable quantitative assessment of tumor blood perfusion. To at least partially address one or more of the above-mentioned problems and other potential issues, this invention proposes a lung tumor magnetic resonance perfusion imaging analysis method that avoids ionizing radiation, eliminates the need for patient breath-holding, and improves image quality and the accuracy of quantitative parameters through prospective motion compensation technology, thus achieving safe, accurate, and repeatable quantitative assessment of lung tumor imaging.

[0028] This invention provides a method for analyzing lung tumors using magnetic resonance perfusion imaging. Figure 1 This is a schematic flowchart of a lung tumor magnetic resonance perfusion imaging analysis method according to an embodiment of the present invention. This method can be applied to a lung tumor magnetic resonance perfusion imaging analysis device. The lung tumor magnetic resonance perfusion imaging analysis device is located in an electronic device. This electronic device includes, but is not limited to, fixed devices and / or mobile devices. For example, fixed devices include, but are not limited to, servers, which can be cloud servers or ordinary servers. Figure 1 As shown, the lung tumor magnetic resonance perfusion imaging analysis method includes: S101. While the subject is breathing freely, the diaphragm movement signal of the subject is obtained through diaphragm navigation.

[0029] S102. Determine respiratory gating conditions based on diaphragmatic motion signals, and generate a prospective motion compensation control signal based on the respiratory gating conditions; the prospective motion compensation control signal is used to ensure that magnetic resonance data acquisition is performed when the respiratory gating conditions are met.

[0030] S103. Using the region where the lung tumor is located as the scanning area, perform three-dimensional dynamic contrast-enhanced magnetic resonance scanning under the control of a prospective motion compensation control signal to obtain a three-dimensional dynamic contrast-enhanced magnetic resonance image sequence including plain scan phases and multiple enhancement phases.

[0031] S104. Perform perfusion quantitative analysis on the three-dimensional dynamic enhanced magnetic resonance image sequence to obtain the time-signal intensity curve and perfusion quantitative parameters of the lung tumor region, and generate perfusion change information based on the reference perfusion quantitative parameters and the perfusion quantitative parameters; the reference perfusion quantitative parameters are the historical perfusion quantitative parameters corresponding to the subjects.

[0032] In this embodiment of the invention, the subject lies supine on an MRI scanning table, maintaining a natural, free breathing state without breath-holding. First, a diaphragm navigation sequence is used to acquire real-time positional changes in the subject's diaphragm caused by respiratory movements. Based on these diaphragm movement signals, suitable respiratory gating conditions for MRI data acquisition are determined. When the diaphragm position meets the respiratory gating conditions, a prospective motion compensation control signal allowing data acquisition is generated; otherwise, acquisition is paused or inhibited.

[0033] Subsequently, the lung lobe containing the lung tumor or the region including the lung tumor and surrounding tissue was used as the three-dimensional dynamic contrast-enhanced magnetic resonance imaging (MRI) scan area. Plain phase images were acquired first, followed by multiple contrast-enhanced phase images after the injection of contrast agent, thus obtaining a three-dimensional dynamic contrast-enhanced MRI image sequence. Perfusion analysis was performed on this image sequence to extract the signal intensity changes of the lung tumor region in each phase, and to generate time-signal intensity curves based on the actual acquisition time of each phase. Perfusion quantitative parameters such as volume transport constant, maximum enhancement slope, and enhancement ratio were calculated. The current perfusion quantitative parameters were compared with reference perfusion quantitative parameters obtained from pre-treatment or previous examinations of the same subject to obtain perfusion change information.

[0034] The technical solution of this invention allows subjects to complete dynamic enhanced perfusion imaging of lung tumors while breathing freely, reducing dependence on breath-holding ability. By using diaphragmatic navigation and prospective motion compensation to reduce respiratory motion artifacts, it improves the consistency of interphase registration and the stability of perfusion parameter calculation during dynamic imaging, thereby facilitating a more objective assessment of perfusion imaging changes before and after lung tumor treatment.

[0035] In some embodiments, while the subject is breathing freely, the diaphragm motion signal of the subject is acquired through diaphragm navigation, including: determining the diaphragm fornix region corresponding to the subject based on the magnetic resonance imaging image corresponding to the subject, and setting a diaphragm navigation sampling area based on the diaphragm fornix region; acquiring diaphragm position signals through the diaphragm navigation sampling area during the subject's free breathing process; and generating diaphragm motion signals based on the diaphragm position signals.

[0036] In this embodiment of the invention, chest MRI localization images of the subject are acquired before scanning, such as coronal or sagittal localization images. The location of the right or left diaphragmatic fornix can be identified based on the localization images, and preferably, a diaphragmatic fornix region with clear motion amplitude and well-defined signal boundaries is selected as the navigation reference area. Subsequently, a diaphragmatic navigation sampling area is set in this region, so that the navigation sampling direction covers the signal interface between the lung base and the liver or tissues near the diaphragm.

[0037] Furthermore, during the subject's free breathing, the magnetic resonance imaging system periodically acquires diaphragm position signals through this diaphragm navigation sampling area, obtaining the displacement changes of the diaphragm in the head-to-foot direction. The continuously acquired diaphragm position signals can be filtered, peak-valley identified, or position tracked to generate diaphragm motion signals reflecting the subject's respiratory motion state.

[0038] Thus, accurately setting the diaphragm navigation sampling area based on the positioning image can improve the reliability and stability of diaphragm position detection and avoid inaccurate gating judgment caused by the navigation sampling area deviating from the diaphragm motion interface; the diaphragm motion signal obtained in this way can more realistically reflect the respiratory motion state of the subject and provide a reliable basis for subsequent respiratory gating and motion compensation.

[0039] In some embodiments, respiratory gating conditions are determined based on diaphragmatic motion signals, and a prospective motion compensation control signal is generated based on the respiratory gating conditions. This includes: determining the end-expiratory phase of the subject's respiratory cycle based on the diaphragmatic motion signals, and setting a navigation reception window based on the end-expiratory phase; determining the current diaphragmatic position based on the diaphragmatic motion signals; generating a prospective motion compensation control signal to characterize allowing magnetic resonance data acquisition when the current diaphragmatic position is within the navigation reception window; and generating a prospective motion compensation control signal to characterize pausing or inhibiting magnetic resonance data acquisition when the current diaphragmatic position is outside the navigation reception window.

[0040] In this embodiment of the invention, the respiratory cycle of the subject can be analyzed based on continuously acquired diaphragmatic movement signals to determine the relatively stable end-expiratory phase of diaphragmatic movement. A navigation receiving window is set with the diaphragm position corresponding to the end-expiratory phase as the center, for example, the receiving window is set to a range with a width of several millimeters centered on the average end-expiratory position.

[0041] During dynamic contrast-enhanced scanning, the current diaphragm position can be acquired in real time, and it can be determined whether the current diaphragm position is within the navigation receiving window. When the current diaphragm position is within the navigation receiving window, a prospective motion compensation control signal is generated to allow magnetic resonance data acquisition, so that the current phase or current k-space data acquisition can continue; when the current diaphragm position is outside the navigation receiving window, a control signal can be generated to pause or inhibit acquisition, waiting for the diaphragm position to re-enter the receiving window before continuing acquisition.

[0042] Thus, by setting the respiratory gating condition near the end of expiration, the relatively stable position of the diaphragm at the end of expiration can be utilized to reduce the respiratory motion displacement of lung tumors and surrounding structures. By prospectively controlling data collection only when the gating condition is met, motion artifacts can be effectively reduced, and the spatial consistency of three-dimensional dynamic enhanced images and the reliability of perfusion curves can be improved.

[0043] In some embodiments, the lung tumor magnetic resonance perfusion imaging analysis method further includes: real-time monitoring of diaphragmatic motion signals during the execution of a three-dimensional dynamic contrast-enhanced magnetic resonance scan; adjusting the position and / or width of the navigation receiving window according to the diaphragmatic motion state of the subject during the examination; and updating the respiratory gating conditions according to the adjusted navigation receiving window.

[0044] In this embodiment of the invention, during the three-dimensional dynamic enhanced magnetic resonance scanning process, the diaphragm motion signal is continuously monitored, and the drift of the diaphragm position, changes in respiratory amplitude, and changes in respiratory rhythm are recorded in real time. When it is detected that the subject's end-expiratory position has shifted upward or downward over time, the center position of the navigation receiving window can be re-determined based on the average end-expiratory position of multiple recent respiratory cycles. When it is detected that the subject's breathing is unstable or the gating pass rate is too low, the width of the navigation receiving window can be appropriately adjusted within the range of ensuring image quality.

[0045] Furthermore, after the adjustment is completed, the updated navigation reception window is used as the new respiratory gating condition to continue generating the corresponding prospective motion compensation control signal and control the data acquisition of the subsequent dynamic enhancement phase.

[0046] In this way, it can adapt to changes in the subject's respiratory state during the examination, avoiding reduced acquisition efficiency caused by the diaphragm's position deviating from the initial receiving window due to respiratory drift. At the same time, by dynamically adjusting the position and / or width of the receiving window, a better balance can be achieved between motion control and scanning time, improving the completion rate and image quality stability of dynamic contrast-enhanced scans during free breathing.

[0047] In some embodiments, a three-dimensional dynamic contrast-enhanced magnetic resonance (MRI) scan is performed with the lung tumor region as the scanning area under the control of a prospective motion compensation control signal to obtain a three-dimensional dynamic contrast-enhanced MRI image sequence including plain scan phases and multiple contrast-enhanced phases. This includes: performing plain scan phase acquisition with the lung tumor region as the scanning coverage area to obtain plain scan phase images; after the subject begins administration of MRI contrast agent, performing multiple contrast-enhanced phase acquisitions under prospective motion compensation control combining diaphragmatic navigation and respiratory gating to obtain a contrast-enhanced phase sequence; and constructing a three-dimensional dynamic contrast-enhanced MRI image sequence based on the acquisition time sequence of the plain scan phase images and the contrast-enhanced phase sequence.

[0048] In this embodiment of the invention, the scanning range is set to cover the entire lung tumor and a certain range of normal lung tissue, pleura, or mediastinal structures surrounding the tumor. First, a three-dimensional T1-weighted plain scan is performed before contrast agent injection to obtain a plain phase image. Subsequently, an intravenous magnetic resonance contrast agent is administered, and multiple three-dimensional enhanced acquisitions are repeated under diaphragmatic navigation and respiratory gating control, with each acquisition forming an enhanced phase image.

[0049] Furthermore, the plain scan phase images and multiple enhancement phase images can be numbered and organized according to the order of acquisition time to form a three-dimensional dynamic enhanced magnetic resonance image sequence containing plain scan phase, early enhancement phase, intermediate enhancement phase and delayed enhancement phase, which can be used for subsequent perfusion quantitative analysis.

[0050] Thus, by first acquiring plain CT images and then continuously acquiring multiple contrast-enhanced images, the dynamic signal changes of lung tumors during contrast agent entry, enhancement rise, and delayed distribution can be fully recorded. Combining diaphragmatic navigation and respiratory gating can reduce respiratory misalignment between different contrast-enhanced phases, making the constructed dynamic image sequence more suitable for calculating time-signal intensity curves and perfusion parameters.

[0051] In some embodiments, after the subject begins administration of magnetic resonance contrast agent, multiple enhancement phase acquisitions are performed under prospective motion compensation control combining diaphragmatic navigation and respiratory gating to obtain an enhancement phase sequence, including: acquiring time information of the start of magnetic resonance contrast agent administration; coordinating the start time of enhancement phase acquisition based on the time information; and continuously performing prospective data acquisition control based on diaphragmatic navigation and respiratory gating during multiple enhancement phase acquisitions to obtain an enhancement phase sequence.

[0052] In this embodiment of the invention, the magnetic resonance system or injection control system records the time information of when the magnetic resonance contrast agent is first administered to the subject. This time information can be manually triggered and input by the operator, or it can be automatically sent by the high-pressure injector communicating with the magnetic resonance system. The start time of the enhancement phase acquisition can be set according to this start time, for example, starting the first enhancement phase acquisition at the same time as the contrast agent is injected or after a predetermined delay.

[0053] During subsequent multiple enhancement-phase acquisitions, diaphragmatic navigation and respiratory gating can be continuously performed. MRI data acquisition for the corresponding enhancement phase is only performed when the diaphragm position meets the current navigation reception window conditions; if the conditions are not met, acquisition is paused and the system waits for the next respiratory state to meet the conditions. This ultimately yields a sequence of enhancement phases arranged chronologically.

[0054] Thus, by acquiring and utilizing the timing information of the start of contrast agent administration, the acquisition of enhancement phases can be coordinated with the timing of the contrast agent entering the bloodstream, reducing the omission of early enhancement information; at the same time, continuous prospective gating control throughout the enhancement acquisition process can take into account both the needs of dynamic perfusion time resolution and respiratory motion inhibition, improving the analyzability of enhancement phase sequences.

[0055] In some embodiments, perfusion quantitative analysis is performed on a three-dimensional dynamic contrast-enhanced magnetic resonance image sequence to obtain time-signal intensity curves and perfusion quantitative parameters of the lung tumor region. Based on reference perfusion quantitative parameters and perfusion quantitative parameters, perfusion change information is generated, including: performing motion correction and baseline correction sequentially on the three-dimensional dynamic contrast-enhanced magnetic resonance image sequence to obtain a corrected image sequence; determining the region of interest in the lung tumor region based on the corrected image sequence and extracting signal intensity change information of the region of interest in different phases; generating a time-signal intensity curve based on the signal intensity change information and the actual acquisition time of each phase, and calculating perfusion quantitative parameters based on the time-signal intensity curve; the perfusion quantitative parameters include at least one of volume transport constant, initial area under the curve, maximum enhancement slope, and contrast agent enhancement ratio; comparing the perfusion quantitative parameters with reference perfusion quantitative parameters to generate perfusion change information.

[0056] In this embodiment of the invention, motion correction can first be performed on the obtained three-dimensional dynamic enhanced magnetic resonance image sequence to make the lung tumor regions in different phases as spatially aligned as possible; then, the signals of the plain scan phase or several phases before enhancement are used as the baseline to perform baseline correction on the signals of each phase, thereby obtaining the corrected dynamic image sequence.

[0057] Furthermore, in the corrected image sequence, the region of lung tumor is manually delineated by the operator or semi-automatically segmented by the system to determine the region of interest (ROI). The average signal intensity or voxel-level signal intensity of the ROI in the plain scan phase and each enhancement phase can be extracted, and a time-signal intensity curve is generated according to the acquisition time. Specifically, when respiratory gating causes inconsistent acquisition intervals in different enhancement phases, the actual acquisition center time of each phase is used as the curve's time coordinate. Subsequently, perfusion quantitative parameters can be calculated based on this curve, including one or more of the following: volume transport constant, initial area under the curve, maximum enhancement slope, and contrast agent enhancement ratio.

[0058] For example, when calculating the volume transport constant, the signal intensity change information of the region of interest in the corrected image sequence can first be converted into a contrast agent concentration-time curve. Subsequently, the contrast agent concentration-time curve can be fitted based on a preset pharmacokinetic model to obtain the volume transport constant.

[0059] Finally, the perfusion quantitative parameters obtained from the current examination can be compared with the reference perfusion quantitative parameters of the same subject to calculate the change in parameters or the percentage change, and to generate perfusion change information, such as information on increased perfusion, decreased perfusion, or no significant change in perfusion. For example, the perfusion change information includes at least one of the following: absolute change in perfusion quantitative parameters, relative percentage change, parameter change trend indicator, and parameter change graph.

[0060] Thus, by performing motion correction and baseline correction on dynamic image sequences, the impact of residual respiratory displacement and baseline signal differences on perfusion analysis can be reduced; through time-signal intensity curves and various perfusion quantitative parameters, the biological changes of lung tumors can be reflected from aspects such as blood supply and contrast agent exchange characteristics; after comparing with historical parameters, perfusion change information is generated, which helps to quantify, continuously and objectively evaluate the treatment response.

[0061] In some implementations, subjects undergo MRI safety screening before the examination to confirm that they do not have pacemakers or other non-magnetically compatible metal implants, and that they are not pregnant and have no history of claustrophobia. Before the examination, subjects are explained the procedure and informed that they do not need to hold their breath; they should simply breathe calmly and evenly as usual. If a subject experiences coughing, significant tension, rapid breathing, or other emergency during the examination, the examination should be stopped immediately to ensure the subject's safety.

[0062] This embodiment uses a GE Architect 3.0T superconducting magnetic resonance scanner, coupled with a 30-channel magic carpet phased array coil for scanning. The subject lies supine with their head first and arms hanging naturally at their sides to improve comfort during prolonged examinations. The center of the body coil is aligned with the area of ​​the lung tumor, ensuring the scan covers the tumor and surrounding tissues.

[0063] During diaphragmatic navigation and localization, a navigation bar is set on the coronal localization image, with the sampling position of the navigation bar placed at the highest point of the right diaphragm. Since the liver is located below the right diaphragm, the diaphragm interface is usually clearer and higher in position; therefore, this embodiment preferably uses the right diaphragm as the navigation reference. The subject's respiratory curve is displayed in real time, and a navigation receiving window is set so that magnetic resonance data acquisition is initiated when the diaphragm displacement is within ±2 mm of the end-expiratory position. During the examination, the position of the navigation bar or the receiving window can be adjusted in a timely manner according to the changes in diaphragm position caused by the subject's actual respiratory movements to improve acquisition efficiency.

[0064] Dynamic contrast-enhanced perfusion scanning employed a lesion-centered T1-weighted imaging (T1WI-3D DISCO) sequence with three-dimensional differential subsampling. Scanning parameters were set as follows: time for repetition (TR) / time for echo (TE) of 3.8 ms / 1.4 ms, slice thickness of 2 mm, no interslice spacing, field of view (FOV) of 400 mm × 320 mm, matrix of 320 × 320, number of signal averages (NSA) of 2, and parallel acceleration factor of 2. The dynamic scan period was set to 25, a recommended value based on experience, corresponding to a total scan time of approximately 10 minutes, to comprehensively reflect the blood perfusion process of lung tumors. In other implementations, the dynamic scan period could be adjusted according to tumor size, subject respiratory rate, or pre- and post-treatment comparison requirements.

[0065] After the initial plain scan, gadolinium contrast agent was administered via the antecubital vein at a dose of 0.1 mmol / kg and an injection flow rate of 2.5 mL / s, followed by flushing with an equal volume of normal saline. The start time of the contrast agent injection was synchronized with the start time of the second phase of dynamic contrast-enhanced scanning. In this embodiment, the operator could manually activate the high-pressure injector button and simultaneously start the contrast-enhanced scanning sequence.

[0066] After the scan, the MRI images are automatically subjected to Maximum Intensity Projection (MIP) and Multi-Planar Reconstruction (MPR) and then sent to the Picture Archiving and Communication System (PACS). MIP and MPR are mainly used to display lung tumors and their blood supply from multiple perspectives, facilitating the observation of the spatial morphology of the lesion and vascular relationships; they do not directly participate in the calculation of perfusion quantitative parameters. Subsequently, the dynamically enhanced image sequence is sent to a workstation, which can be a computer equipped with perfusion analysis software.

[0067] After loading the dynamic series of images into the workstation, the perfusion analysis module is accessed. Following motion and baseline correction, the operator manually delineates the region of interest (ROI) in the area of ​​most significant solid enhancement of the tumor. Once delineated, time-signal intensity curves are automatically generated based on the actual acquisition times of each phase, and perfusion-related quantitative parameters are automatically calculated, such as transport constant (Ktrans), initial area under the Gadolinium Concentration-Time Curve (IAUGC), maximum enhancement slope, and contrast agent enhancement ratio. For pre- and post-treatment comparisons, it is preferable to use the same scanning sequence, contrast agent injection protocol, and post-processing reconstruction method to ensure consistency in parameter comparison. A comprehensive evaluation can be performed by combining changes in tumor size, morphology, and perfusion-related quantitative parameters.

[0068] Figure 2 A first comparison image of MRI perfusion images and enhanced CT images in an embodiment of the present invention is shown, such as... Figure 2 As shown in the left MRI perfusion image of a lung tumor case, post-perfusion analysis of the MRI showed a Ktrans value of 0.569. The IAUGC value was 0.371, indicating significant contrast agent exchange and enhancement characteristics in the lesion area. This functional parameter information can be correlated with the enhancement pattern shown on enhanced CT, and compared with enhanced CT, magnetic resonance perfusion analysis can further provide functional information reflecting tumor hemodynamics and tissue permeability.

[0069] Figure 3 A second comparison image of MRI perfusion images and enhanced CT images in an embodiment of the present invention is shown, such as... Figure 3 As shown, in another case of lung tumor, MRI post-perfusion analysis revealed a Ktrans value of 1.677. The IAUGC was 0.932, and the maximum enhancement slope and contrast agent enhancement ratio were also high, indicating that the lesion area had obvious perfusion and enhancement characteristics. This functional parameter information can be compared with the enhancement pattern shown on enhanced CT, and compared with enhanced CT, magnetic resonance perfusion analysis can further provide functional information reflecting tumor hemodynamics and tissue permeability.

[0070] It should be understood that Figure 2 and Figure 3 The schematic diagrams shown are merely illustrative and not limiting, and are scalable; those skilled in the art can use them as a basis. Figure 2 and Figure 3 Even with various obvious changes and / or substitutions to the examples, the resulting technical solutions still fall within the scope of the disclosure of the embodiments of this invention.

[0071] This invention provides a lung tumor magnetic resonance perfusion imaging analysis device, such as... Figure 4 As shown, the device may include: a diaphragm navigation module 401, used to acquire diaphragm motion signals of the subject while the subject is breathing freely; a signal generation module 402, used to determine respiratory gating conditions based on diaphragm motion signals and generate a prospective motion compensation control signal based on the respiratory gating conditions; the prospective motion compensation control signal is used to ensure that magnetic resonance data acquisition is performed when the respiratory gating conditions are met; a scan control module 403, used to perform three-dimensional dynamic contrast-enhanced magnetic resonance scanning with the lung tumor area as the scan area under the control of the prospective motion compensation control signal, to obtain a three-dimensional dynamic contrast-enhanced magnetic resonance image sequence including plain scan phases and multiple enhancement phases; and an image analysis module 404, used to perform perfusion quantitative analysis on the three-dimensional dynamic contrast-enhanced magnetic resonance image sequence, to obtain the time-signal intensity curve and perfusion quantitative parameters of the lung tumor area, and to generate perfusion change information based on reference perfusion quantitative parameters and perfusion quantitative parameters; the reference perfusion quantitative parameters are historical perfusion quantitative parameters corresponding to the subject.

[0072] The specific functions and examples of each module and submodule of the device in this embodiment of the invention can be found in the relevant descriptions of the corresponding steps in the above method embodiments, and will not be repeated here.

[0073] The lung tumor magnetic resonance perfusion imaging analysis device in this embodiment of the invention allows subjects to complete dynamic enhanced perfusion imaging of lung tumors under free breathing conditions, reducing dependence on breath-holding ability. By reducing respiratory motion artifacts through diaphragmatic navigation and prospective motion compensation, it improves the consistency of interphase registration and the stability of perfusion parameter calculation during dynamic imaging, thereby facilitating a more objective assessment of perfusion imaging changes before and after lung tumor treatment.

[0074] The acquisition, storage, and application of user personal information involved in the technical solution of this invention all comply with the provisions of relevant laws and regulations and do not violate public order and good morals.

[0075] According to embodiments of the present invention, the present invention also provides an electronic device and a readable storage medium.

[0076] Figure 5A schematic block diagram of an example electronic device 500 that can be used to implement embodiments of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0077] like Figure 5 As shown, device 500 includes a computing unit 501, which can perform various appropriate actions and processes based on a computer program stored in read-only memory (ROM) 502 or a computer program loaded from storage unit 508 into random access memory (RAM) 503. RAM 503 may also store various programs and data required for the operation of device 500. The computing unit 501, ROM 502, and RAM 503 are interconnected via bus 504. Input / output (I / O) interface 505 is also connected to bus 504.

[0078] Multiple components in device 500 are connected to I / O interface 505, including: input unit 506, such as keyboard, mouse, etc.; output unit 507, such as various types of monitors, speakers, etc.; storage unit 508, such as disk, optical disk, etc.; and communication unit 509, such as network card, modem, wireless transceiver, etc. Communication unit 509 allows device 500 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0079] The computing unit 501 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 501 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, digital signal processors (DSPs), and any suitable processor, controller, microcontroller, etc. The computing unit 501 performs the various methods and processes described above, such as the lung tumor magnetic resonance perfusion imaging analysis method. For example, in some embodiments, the lung tumor magnetic resonance perfusion imaging analysis method can be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as storage unit 508. In some embodiments, part or all of the computer program can be loaded and / or installed on device 500 via ROM 502 and / or communication unit 509. When the computer program is loaded into RAM 503 and executed by the computing unit 501, one or more steps of the lung tumor magnetic resonance perfusion imaging analysis method described above can be performed. Alternatively, in other embodiments, the computing unit 501 may be configured to perform a lung tumor magnetic resonance perfusion imaging analysis method by any other suitable means (e.g., by means of firmware).

[0080] In some implementations, the electronic device can be a scan control workstation of a magnetic resonance imaging (MRI) scanner, a perfusion analysis workstation communicatively connected to the MRI scanner, or a server communicatively connected to both the MRI scanner and the injection control device. The electronic device can send scan control commands to the MRI scanner via a communication interface and receive diaphragmatic motion signals and three-dimensional dynamic contrast-enhanced MRI image sequences.

[0081] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0082] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for analyzing lung tumors using magnetic resonance perfusion imaging, characterized in that, include: While the subject was breathing freely, the diaphragm movement signal of the subject was acquired through diaphragm navigation; The respiratory gating condition is determined based on the diaphragm motion signal, and a prospective motion compensation control signal is generated according to the respiratory gating condition; the prospective motion compensation control signal is used to ensure that magnetic resonance data acquisition is performed when the respiratory gating condition is met. Using the region where the lung tumor is located as the scanning area, a three-dimensional dynamic contrast-enhanced magnetic resonance scan is performed under the control of the prospective motion compensation control signal to obtain a three-dimensional dynamic contrast-enhanced magnetic resonance image sequence including plain scan phases and multiple enhancement phases; Perfusion quantitative analysis was performed on the three-dimensional dynamic enhanced magnetic resonance image sequence to obtain the time-signal intensity curve and perfusion quantitative parameters of the lung tumor region, and perfusion change information was generated based on the reference perfusion quantitative parameters and the perfusion quantitative parameters. The reference irrigation quantitative parameters are the historical irrigation quantitative parameters corresponding to the test subjects.

2. The method according to claim 1, characterized in that, The step of acquiring the diaphragmatic movement signal of the subject through diaphragmatic navigation while the subject maintains free breathing includes: Based on the magnetic resonance imaging corresponding to the subject, the diaphragmatic fornix region corresponding to the subject is determined, and the diaphragmatic navigation sampling area is set according to the diaphragmatic fornix region. During the subject's free breathing process, the diaphragm position signal was acquired through the diaphragm navigation sampling area; The diaphragm movement signal is generated based on the diaphragm position signal.

3. The method according to claim 1, characterized in that, The step of determining respiratory gating conditions based on the diaphragmatic movement signal and generating a prospective motion compensation control signal based on the respiratory gating conditions includes: Based on the diaphragmatic movement signal, the end-expiratory phase of the subject's respiratory cycle is determined, and the navigation reception window is set based on the end-expiratory phase. The current position of the diaphragm is determined based on the diaphragm movement signal; When the current diaphragm position is within the navigation receiving window, a prospective motion compensation control signal is generated to characterize allowing the execution of magnetic resonance data acquisition; When the current diaphragm position is outside the navigation receiving window, a prospective motion compensation control signal is generated to characterize the suspension or suppression of magnetic resonance data acquisition.

4. The method according to claim 3, characterized in that, The method further includes: The diaphragm motion signal is monitored in real time during the three-dimensional dynamic enhanced magnetic resonance scan. The position and / or width of the navigation receiving window are adjusted according to the diaphragm movement state of the test subject during the examination. The breathing gating conditions are updated based on the adjusted navigation acceptance window.

5. The method according to claim 1, characterized in that, The method involves using the region where the lung tumor is located as the scanning area, and performing a three-dimensional dynamic contrast-enhanced magnetic resonance (MRI) scan under the control of the prospective motion compensation control signal to obtain a three-dimensional dynamic contrast-enhanced MRI image sequence including plain scan phases and multiple enhancement phases, including: Using the area where the lung tumor is located as the scanning coverage area, plain scan phase acquisition is performed to obtain plain scan phase images; After the subjects were given magnetic resonance contrast agent, multiple enhancement phase acquisitions were performed under prospective motion compensation control with diaphragmatic navigation and respiratory gating to obtain enhancement phase sequences. Based on the plain scan phase images and the enhancement phase sequence, a three-dimensional dynamic enhanced magnetic resonance image sequence is constructed according to the acquisition time sequence.

6. The method according to claim 5, characterized in that, After the subjects were given magnetic resonance contrast agent, multiple enhancement phase acquisitions were performed under prospective motion compensation control with diaphragmatic navigation and respiratory gating to obtain enhancement phase sequences, including: Obtain information on the timing of the start of magnetic resonance contrast agent administration; The start time of the enhanced phase acquisition is coordinated based on the aforementioned time information; The enhancement phase sequence was obtained by continuously performing prospective data acquisition control based on diaphragmatic navigation and respiratory gating during multiple enhancement phase acquisitions.

7. The method according to claim 1, characterized in that, The perfusion quantitative analysis of the three-dimensional dynamic enhanced magnetic resonance image sequence is performed to obtain the time-signal intensity curve and perfusion quantitative parameters of the lung tumor region. Based on the reference perfusion quantitative parameters and the perfusion quantitative parameters, perfusion change information is generated, including: The three-dimensional dynamic enhanced magnetic resonance image sequence is sequentially subjected to motion correction and baseline correction to obtain the corrected image sequence; Based on the corrected image sequence, a region of interest is determined in the area where the lung tumor is located, and the signal intensity change information of the region of interest in different phases is extracted; Based on the signal intensity change information and the actual acquisition time of each phase, a time-signal intensity curve is generated, and perfusion quantitative parameters are calculated based on the time-signal intensity curve; the perfusion quantitative parameters include at least one of the following: volume translocation constant, initial area under the curve, maximum enhancement slope, and contrast agent enhancement ratio; The irrigation quantity parameters are compared with the reference irrigation quantity parameters to generate the irrigation change information.

8. A magnetic resonance perfusion imaging analysis device for lung tumors, characterized in that, include: The diaphragm navigation module is used to acquire the diaphragm movement signal of the subject while the subject is breathing freely; A signal generation module is used to determine respiratory gating conditions based on the diaphragm motion signal, and generate a prospective motion compensation control signal according to the respiratory gating conditions; the prospective motion compensation control signal is used to enable magnetic resonance data acquisition to be performed when the respiratory gating conditions are met; The scanning control module is used to perform three-dimensional dynamic contrast-enhanced magnetic resonance scanning under the control of the prospective motion compensation control signal, with the region where the lung tumor is located as the scanning area, to obtain a three-dimensional dynamic contrast-enhanced magnetic resonance image sequence including plain scan phase and multiple enhancement phases. The image analysis module is used to perform perfusion quantitative analysis on the three-dimensional dynamic enhanced magnetic resonance image sequence, obtain the time-signal intensity curve and perfusion quantitative parameters of the lung tumor region, and generate perfusion change information based on the reference perfusion quantitative parameters and the perfusion quantitative parameters. The reference irrigation quantitative parameters are the historical irrigation quantitative parameters corresponding to the test subjects.

9. An electronic device, characterized in that, include: At least one processor; as well as A memory that is communicatively connected to at least one processor; wherein, The memory stores instructions that can be executed by at least one processor to enable the at least one processor to perform the method of any one of claims 1-7.

10. A non-transitory computer-readable storage medium storing computer instructions, characterized in that, The computer instructions are used to cause the computer to perform the method according to any one of claims 1-7.

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