Cardiac magnetic resonance full-free breathing examination method, device, equipment and product

Abstract

The present application discloses a cardiac magnetic resonance fully free breathing examination method, device, equipment and product, which are applied to the field of magnetic resonance imaging technology. The method obtains the current heart rate of the test object in real time; for each scanning stage, the corresponding scanning parameters are determined based on the current heart rate, and finally the corresponding target part is scanned based on the scanning parameters to obtain the cardiac magnetic resonance image of the test object. This solution will collect the heart rate in real time during the scanning process, and determine the appropriate scanning parameters at different heart rates, which greatly reduces the time required for scanning while ensuring the image quality. The test object is no longer required to hold his breath to cooperate, and the breath-holding command and breath-holding interval time during the examination are eliminated, thereby greatly reducing the total imaging time. It can be seen that this solution is highly operational and practical, and has great potential for clinical application.

Description

Technical Field

[0001] The present application belongs to the field of magnetic resonance imaging technology, and in particular, relates to a cardiac magnetic resonance full-free breathing examination method, device, equipment and product. Background Art

[0002] Magnetic resonance imaging is widely used in medical scenarios because of its good soft tissue contrast and non-radioactive characteristics. For example, cardiac magnetic resonance imaging has comprehensive functions, high spatial and temporal resolution, and high soft tissue contrast, and has great clinical value.

[0003] Currently, during cardiac magnetic resonance imaging, the subject is required to hold their breath repeatedly (30 to 40 times) to coordinate with the image and ensure image quality. This results in a long examination time and a poor experience for the subject. For infants and children and those with heart failure, magnetic resonance imaging cannot be successfully completed. Summary of the invention

[0004] The embodiments of the present application provide a cardiac magnetic resonance fully free breathing examination method, device, equipment and product, which eliminates the requirement for the test subject to hold his breath, thereby shortening the examination time, improving the test subject's experience, and increasing the success rate of the examination.

[0005] On the one hand, the embodiment of the present application provides a cardiac magnetic resonance full free breathing examination method, comprising:

[0006] Acquire multiple target parts of the detected object and acquire the current heart rate of the detected object in real time;

[0007] For each scanning stage in the cardiac magnetic resonance scanning process, the scanning parameters corresponding to the scanning stage are determined based on the current heart rate of the detected object; the scanning parameters include at least any one of the following items or any combination: the size of the acquisition matrix, the number of restored heartbeats, and the time resolution; the size of the acquisition matrix is ​​negatively correlated with the current heart rate of the detected object, and the time resolution and the number of restored heartbeats are positively correlated with the current heart rate of the detected object;

[0008] Based on the scanning parameters of each scanning phase, the corresponding target part is scanned to obtain a cardiac magnetic resonance image of the detection object.

[0009] On the other hand, the target site at least includes: a first target site, a second target site, a third target site and a fourth target site; the first target site includes: left ventricular base, middle and apex short axis sites; the second target site includes: three layers of short axis sites and one layer of four chamber sites; the third target site includes: two chamber sites, four chamber sites, a group of parallel multi-layer short axis sites, left ventricular outflow tract and oblique coronal left ventricular outflow tract layer; the fourth target site includes: two chamber sites, four chamber sites and a group of parallel multi-layer short axis sites;

[0010] The scanning parameters at least include: a first scanning parameter, a second scanning parameter, a third scanning parameter, a fourth scanning parameter and a fifth scanning parameter;

[0011] Scanning the corresponding target part based on the scanning parameters of each scanning phase to obtain a cardiac magnetic resonance image of the detection object includes:

[0012] Before injecting the contrast agent, scanning the first target site based on the first scanning parameter to obtain a first longitudinal relaxation time quantitative image;

[0013] Scanning the first target site based on a second scanning parameter to obtain a transverse relaxation time quantitative image;

[0014] While injecting the contrast agent, scanning the second target site to obtain a first-pass perfusion image of the heart;

[0015] Scanning the third target part to obtain a cardiac function movie image; scanning the third target part based on the third scanning parameter when the heart rhythm of the detected object meets a preset condition;

[0016] Based on the fourth scanning parameter, scanning the fourth target part to obtain a delayed enhancement image; the delayed enhancement image includes a single-excitation delayed enhancement image and a high-resolution motion-corrected delayed enhancement image;

[0017] After the contrast agent is injected, the first target site is scanned based on the fifth scanning parameter to obtain a second longitudinal relaxation time quantitative image.

[0018] On the other hand, the first scanning parameter includes at least the size of the acquisition matrix and the number of recovery heartbeats for completing data acquisition after the first inversion pulse.

[0019] On the other hand, the second scanning parameter at least includes the number of recovery heartbeats for which data acquisition is completed after the T2 preparation pulse.

[0020] On the other hand, the third scanning parameter includes the size of the acquisition matrix and the time resolution;

[0021] Scanning the third target site to obtain a cardiac function movie image includes:

[0022] When the heart rhythm condition satisfies the preset condition, scanning the third target part based on the acquisition matrix and the time resolution to obtain the cardiac function movie image;

[0023] When the heart rhythm condition does not satisfy the preset condition, the third target site is single-excited and scanned in real time to obtain the cardiac function movie image.

[0024] On the other hand, when the heart rhythm condition satisfies the preset condition, scanning the third target part based on the acquisition matrix and the time resolution to obtain the cardiac function movie image includes:

[0025] Acquiring real-time movie data of multiple heartbeat cycles and respiratory cycles; the real-time movie data includes k-space data;

[0026] remapping the acquired k-space data according to a preset trigger delay to obtain a plurality of normalized heartbeat subsets;

[0027] Reconstructing the normalized heartbeat subset;

[0028] sorting the reconstructed subset of heartbeats based on end-expiratory image quality;

[0029] Determine a preset number of heartbeat subsets ranked first as target heartbeat subsets;

[0030] non-rigidly registering a reference heartbeat with the target heartbeat subset;

[0031] The cardiac function movie image is determined based on the average value of the registered target heartbeat subset.

[0032] On the other hand, the fourth scanning parameter includes the size of the acquisition matrix and the time resolution.

[0033] On the other hand, the fifth scanning parameter includes the size of the acquisition matrix and the number of recovery heartbeats after the first inversion pulse to complete data acquisition and the number of recovery heartbeats after the second inversion pulse to complete data acquisition.

[0034] On the other hand, after the contrast agent is injected, the first target site is scanned based on the fifth scanning parameter to obtain a second longitudinal relaxation time quantitative image, the method further includes:

[0035] Determining a tolerance state of the detection object;

[0036] When the test subject tolerates the condition, the corresponding target part is scanned to obtain a compressed sensing whole-heart coronary image based on image navigation and / or a compressed sensing whole-heart four-dimensional blood flow image based on diaphragm navigation.

[0037] On the other hand, the target site also includes: a fifth target site; the fifth target site includes: a four-chamber position and a left ventricular outflow tract position;

[0038] After scanning the third target part to obtain a cardiac function movie image and before scanning the fourth target part based on the fourth scanning parameter, the method further includes:

[0039] In the case where there is a problem with the valve of the detection object, a phase contrast blood flow image is taken for the fifth target site.

[0040] On the other hand, the embodiment of the present application provides a cardiac magnetic resonance full-free breathing examination device, the device comprising:

[0041] An acquisition module, used to acquire multiple target parts of the detection object and to acquire the current heart rate of the detection object in real time;

[0042] A determination module, for determining, for each scanning stage in the cardiac magnetic resonance scanning process, scanning parameters corresponding to the scanning stage based on the current heart rate of the detection object; the scanning parameters include at least any one of the following or any combination: the size of the acquisition matrix, the number of restored heartbeats, and the time resolution; the size of the acquisition matrix is ​​negatively correlated with the current heart rate of the detection object, and the time resolution and the number of restored heartbeats are positively correlated with the current heart rate of the detection object;

[0043] The scanning module is used to scan the corresponding target part based on the scanning parameters of each scanning stage to obtain the cardiac magnetic resonance image of the detection object.

[0044] In another aspect, an embodiment of the present application provides a cardiac magnetic resonance full-free breathing examination device, the device comprising: a processor and a memory storing computer program instructions;

[0045] When the processor executes the computer program instructions, the cardiac magnetic resonance full free breathing examination method as described above is implemented.

[0046] On the other hand, an embodiment of the present application provides a computer-readable storage medium having computer program instructions stored thereon, and when the computer program instructions are executed by a processor, the cardiac magnetic resonance full-free breathing examination method as described above is implemented.

[0047] On the other hand, an embodiment of the present application provides a computer program product. When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes the cardiac magnetic resonance full free breathing examination method as described above.

[0048] A cardiac magnetic resonance full-free breathing examination method of the embodiment of the present application first obtains multiple target parts of the test object and obtains the current heart rate of the test object in real time; then, for each scanning stage in the cardiac magnetic resonance scanning process, the corresponding scanning parameters in the corresponding scanning stage are determined based on the current heart rate of the test object, such as the size of the acquisition matrix, the number of restored heartbeats, and the time resolution of the movie sequence. Finally, based on the scanning parameters of each scanning stage, the corresponding target part is scanned to obtain the cardiac magnetic resonance image of the test object. The scheme proposed in the embodiment of the present application will collect the heart rate in real time during the scanning process, and determine the appropriate scanning parameters at different heart rates, which greatly reduces the time required for scanning while ensuring the image quality. The test object is no longer required to hold his breath to cooperate, and the breath-holding command and breath-holding interval time during the inspection process are removed. Because the appropriate scanning parameters will not increase unnecessary time, the total imaging time is greatly reduced. It can be seen that this scheme is highly operational and practical, and has great potential for clinical application. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0050] Figure 1 A schematic diagram showing a flow chart of a cardiac magnetic resonance full free breathing examination method provided by an embodiment of the present application is shown;

[0051] Figure 2 A schematic diagram of the complete process of cardiac magnetic resonance full free breathing examination provided by an embodiment of the present application is shown;

[0052] Figure 3 A schematic diagram of the structure of a cardiac magnetic resonance full-free breathing examination device provided in an embodiment of the present application is shown;

[0053] Figure 4 A schematic diagram of the hardware structure of a cardiac magnetic resonance free breathing examination device provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0054] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0055] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "include..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0056] During traditional cardiac magnetic resonance scanning, patients are required to hold their breath multiple times, which not only takes a long time, but also does not cover infants and people with heart failure who cannot cooperate with breath holding. In order to solve the problems of traditional solutions, the embodiments of the present application provide a cardiac magnetic resonance full free breathing examination method, device, equipment and product. The following first introduces the cardiac magnetic resonance full free breathing examination method provided in the embodiments of the present application. Figure 1 FIG. 1 is a flow chart of a cardiac magnetic resonance free breathing examination method provided by an embodiment of the present application. Figure 1 As shown, the method includes the following steps: S101 to S103.

[0057] S101: Acquire multiple target parts of the detection object and acquire the current heart rate of the detection object in real time.

[0058] Cardiac magnetic resonance scanning is divided into multiple scanning stages. Before scanning, the target area that needs to be imaged by magnetic resonance imaging must be acquired first, and then the corresponding area can be scanned in each scanning stage.

[0059] All sequences in the present application embodiment are scanned in free breathing mode, thereby eliminating the burden of breath holding for the patient, and no voice commands and breath holding intervals are required. The specific sequences are as follows:

[0060] The standard positioning image, the Balanced Steady-State Free Precession (bSSFP) sequence, obtains large-scale coronal and sagittal images to show the position of the heart.

[0061] The cardiac three-plane positioning image, electrocardiographic gating (ECG) synchronized single shot (SS) bSSFP sequence, is positioned at the center of the heart to collect multi-layer standard transverse, coronal, and sagittal images.

[0062] Transverse and sagittal anatomical imaging, Half Fourier Acquisition Single Shot Turbo Spine Echo (HASTE) sequence, collects a set of parallel transverse positions, positioning from the aortic arch to the bottom of the heart; and a set of parallel sagittal positions, positioning the entire heart.

[0063] The cardiac two-chamber positioning image is obtained by synchronizing the ECG SS bSSFP sequence and obtaining the left ventricular two-chamber positioning image according to the positioning specifications.

[0064] Four-chamber positioning image of the heart, ECG synchronized SS bSSFP sequence, and the four-chamber positioning image of the left ventricle was obtained according to the positioning specifications.

[0065] For cardiac short-axis positioning images, the ECG is synchronized with the SS bSSFP sequence to obtain a set of parallel multi-slice left ventricular short-axis positioning images according to the positioning specifications.

[0066] S102: For each scanning stage in the cardiac magnetic resonance scanning process, determining corresponding scanning parameters in the corresponding scanning stage based on the current heart rate of the detected subject.

[0067] The scanning parameters include at least any one or any combination of the following: the size of the acquisition matrix, the number of recovered heartbeats, and the time resolution; the size of the acquisition matrix is ​​negatively correlated with the current heart rate of the detected object, and the time resolution and the number of recovered heartbeats are positively correlated with the current heart rate of the detected object.

[0068] Here is a specific scanning imaging process: the first step is to perform longitudinal relaxation time quantitative imaging (i.e. Pre T1 Mapping) before contrast agent injection; the second step is transverse relaxation time quantitative imaging (i.e. T2 Mapping); the third step is first-pass perfusion imaging; the fourth step is cardiac function movie imaging; the fifth step is to determine whether there is a problem with the valve, and if there is a problem, perform phase contrast blood flow imaging; the sixth step is delayed enhancement imaging; the seventh step is to perform longitudinal relaxation time quantitative imaging again (i.e. Post T1 Mapping) after contrast agent injection. In addition, whole-heart coronary imaging based on image navigation and compressed sensing whole-heart four-dimensional blood flow imaging (i.e. 4D FLOW imaging) based on diaphragm navigation can be added according to clinical needs.

[0069] Each step in the above text is a scanning stage. In each scanning stage, the current heart rate of the detected object is obtained in real time, and then the corresponding scanning parameters in the corresponding scanning stage are determined based on the current heart rate of the detected object, such as setting the size of the acquisition matrix, restoring the number of heartbeats, and time resolution, etc.

[0070] S103: Scan the corresponding target part based on the scanning parameters of each scanning phase to obtain a cardiac magnetic resonance image of the detection object.

[0071] After the corresponding scanning parameters are determined based on the current heart rate of the detected object, in each scanning phase, the corresponding target part is scanned based on the determined scanning parameters to obtain a cardiac magnetic resonance image of the detected object.

[0072] The scheme proposed in the embodiment of the present application sets different acquisition schemes according to different heart rates in each scanning stage of cardiac magnetic resonance imaging. For example, as the heart rate increases, the corresponding increase in time resolution can better freeze the heart movement. For another example, under different heart rates, the time required for complete relaxation in the longitudinal relaxation time quantitative imaging and transverse relaxation time quantitative imaging processes is different. As the heart rate increases, setting a larger recovery heartbeat number can make relaxation complete. In addition, in order to improve the time resolution and ensure image quality, the size of the acquisition matrix can be appropriately increased.

[0073] However, it should be noted that adjusting the above scanning parameters can improve image quality, but it will also bring other defects. Therefore, it is necessary to determine the most appropriate scanning parameters based on the heart rate to ensure image quality while avoiding defects such as excessive imaging time.

[0074] For example, if the recovery heart rate is set too high, although it can ensure complete relaxation, it will increase the total imaging time. In addition, the acquisition matrix used for scanning is positively correlated with the temporal resolution, but negatively correlated with the spatial resolution. While increasing the size of the acquisition matrix to improve the temporal resolution, it is necessary to ensure sufficient spatial resolution.

[0075] Specifically, in the longitudinal relaxation time quantitative imaging process, it is necessary to scan the first target part based on the acquisition matrix, the acquisition heartbeat number and the recovery heartbeat number to obtain the longitudinal relaxation time quantitative image. The acquisition matrix and the recovery heartbeat number here can be set according to the current heart rate of the detected object, so as to ensure the image quality and imaging speed.

[0076] During the transverse relaxation time quantitative imaging process, it is necessary to scan the first target site based on the recovery heart rate. The recovery heart rate at this time can also be set according to the current heart rate of the detected object.

[0077] During cardiac function movie imaging, the corresponding acquisition matrix and time resolution can be set according to the current heart rate of the subject. During delayed enhancement imaging, the corresponding acquisition matrix and time resolution can be set according to the current heart rate of the subject.

[0078] Through the scheme proposed in the embodiment of the present application, the test subject can breathe freely throughout the whole process of cardiac magnetic resonance imaging without holding the breath, the artifacts caused by arrhythmia are relatively small, the image quality is stable, and the examination time is shortened from 40 minutes of breath-holding examination to about 20 minutes.

[0079] It can be seen that the embodiment of the present application realizes cardiac magnetic resonance examination under full free breathing. Compared with the traditional breath-holding examination, this solution eliminates the breath-holding burden of the test object, greatly shortens the examination time, has a significant impact on the current cardiac magnetic resonance working mode, and completely solves the imaging obstacles of patients with breath-holding difficulties. It provides a solution for cardiac movie imaging of patients with arrhythmia, and greatly expands the clinical application scenarios of cardiac magnetic resonance imaging. In a short period of time, seven major contents including cardiac anatomy, function, myocardial perfusion, myocardial activity, precise quantification of myocardial tissue characteristics, hemodynamics and coronary imaging are completed, solving the shortcomings of the traditional process such as long examination time and limited imaging content.

[0080] A cardiac magnetic resonance full-free breathing examination method of the embodiment of the present application first obtains multiple target parts of the test object and obtains the current heart rate of the test object in real time; then, for each scanning stage in the cardiac magnetic resonance scanning process, the corresponding scanning parameters in the corresponding scanning stage are determined based on the current heart rate of the test object, such as the size of the acquisition matrix, the number of restored heartbeats, and the time resolution of the movie sequence. Finally, based on the scanning parameters of each scanning stage, the corresponding target part is scanned to obtain the cardiac magnetic resonance image of the test object. The scheme proposed in the embodiment of the present application will collect the heart rate in real time during the scanning process, and determine the appropriate scanning parameters at different heart rates, which greatly reduces the time required for scanning while ensuring the image quality. The test object is no longer required to hold his breath to cooperate, and the breath-holding command and breath-holding interval time during the inspection process are removed. Because the appropriate scanning parameters will not increase unnecessary time, the total imaging time is greatly reduced. It can be seen that this scheme is highly operational and practical, and has great potential for clinical application.

[0081] The above embodiment mentioned that there are multiple scanning stages in the process of cardiac magnetic resonance scanning. In different scanning stages, the corresponding target parts need to be scanned based on the corresponding scanning parameters. This embodiment provides a specific implementation scheme, and the target parts include at least: a first target part, a second target part, a third target part and a fourth target part; the first target part includes: short-axis positions of the left ventricular base, middle and apex; the second target part includes: three-layer short-axis positions and one-layer four-chamber position; the third target part includes: two-chamber position, four-chamber position, a group of parallel multi-layer short-axis positions, left ventricular outflow tract and oblique coronal position left ventricular outflow tract level. The fourth target part includes: four-chamber position, two-chamber position and a group of parallel multi-layer short-axis positions. The scanning parameters include at least: a first scanning parameter, a second scanning parameter, a third scanning parameter, a fourth scanning parameter and a fifth scanning parameter.

[0082] Figure 2 The complete process diagram of cardiac magnetic resonance free breathing examination provided by an embodiment of the present application is shown. Figure 2 As shown, the complete scanning imaging process includes: S201 to S212.

[0083] S201: Locate each target part.

[0084] As described above, each scanning stage in the cardiac magnetic resonance scanning process scans the corresponding target parts, and the specific locations of these target parts need to be determined in advance.

[0085] S202: Before injecting a contrast agent, scan a first target site based on a first scanning parameter to obtain a first longitudinal relaxation time quantitative image.

[0086] The first scanning parameter includes at least the size of the acquisition matrix and the number of recovery heartbeats; at this time, the size of the acquisition matrix is ​​negatively correlated with the current heart rate of the detection object, and the number of recovery heartbeats is positively correlated with the current heart rate of the detection object.

[0087] The first target area includes the left ventricular base, middle and apex short axis, and the longitudinal relaxation time quantitative imaging (i.e. Pre T1 mapping) before contrast agent injection is a motion-corrected Look Locker Inversion Recovery (Modified Look Locker Inversion Recovery, MOLLI) sequence. For different heart rate scenarios, the time resolution, spatial resolution and inversion recovery heart rate are weighed; different scanning parameters are set in different heart rate ranges.

[0088] When acquiring the first longitudinal relaxation time quantitative image, by setting the acquisition matrix of corresponding size at different heart rates of the detected object and the number of recovered heartbeats after data acquisition is completed after the first inversion pulse, the first longitudinal relaxation time quantitative image that meets the quality requirements can be obtained at each heart rate without causing the scanning time to be too long.

[0089] S203: Scanning the first target site based on the second scanning parameter to obtain a transverse relaxation time quantitative image.

[0090] The second scanning parameter at least includes the number of recovery heartbeats after the T2 preparation pulse when data collection is completed (ie, the T2 preparation recovery heartbeat number); the T2 preparation recovery heartbeat number is positively correlated with the current heart rate of the detected subject.

[0091] When performing transverse relaxation time quantitative imaging (i.e., T2 mapping), the first target part is also scanned, i.e., the left ventricular base, middle, and apex short axis. T2 mapping is a conventional sequence, and T2 preparation is a single-shot bSSFP sequence. Three different T2 preparation times can be used, i.e., 0, 35, and 55 ms. Different T2 preparation recovery heart rates are set for different heart rate scenarios.

[0092] When scanning the first target part and obtaining the transverse relaxation time quantitative image, by setting the T2 preparation recovery heart rate of corresponding size at different heart rates of the detected object, the transverse relaxation time quantitative image that meets the quality requirements can be obtained at each heart rate without causing the defect of too long image acquisition time.

[0093] S204: While injecting the contrast agent, scanning the second target site to obtain a first-pass perfusion image of the heart.

[0094] First-pass perfusion imaging is a motion-corrected saturation recovery rapid gradient echo sequence. The scan is started at the same time as the contrast agent is injected, and dynamic images of three-layer short-axis and one-layer four-chamber are obtained over multiple consecutive cardiac cycles. During the scanning process, motion-corrected dynamic perfusion movies are used to improve the accuracy of detecting pixel signal intensity changes and reduce the impact of motion on quantitative analysis results.

[0095] S205: Scan the third target site to obtain a cardiac function movie image.

[0096] During cardiac function movie imaging, the heart rhythm of the subject is first determined. If the arrhythmia is severe, Compressed Sensing (CS) SS is selected to retrospectively reconstruct the bSSFP sequence, combined with 8 seconds of compressed sensing to collect the bSSFP movie sequence in real time. If the heart rhythm is regular or slightly irregular, the SS multiple average motion correction movie sequence is used. For different heart rate scenarios, the time resolution, spatial resolution and compressed sensing acceleration factor are weighed, and different heart rate intervals correspond to different parameter settings. The scanning levels include two-chamber position, four-chamber position, a set of parallel multi-layer short-axis position, left ventricular outflow tract, and oblique coronary position left ventricular outflow tract level.

[0097] The specific scanning process includes:

[0098] When the heart rhythm condition meets the preset conditions, the third target part is scanned based on the acquisition matrix and time resolution to obtain a movie image of the heart function; the specific content of the preset conditions is not limited and is set according to actual needs. The heart rhythm condition meets the preset conditions to indicate that the heart rhythm of the test object is regular or slightly irregular. At this time, the prospective compressed sensing movie acquisition plus retrospective intelligent motion correction sequence is selected to reject a small amount of arrhythmia, multiple averaging improves the signal-to-noise ratio, and motion correction improves the accuracy of the data. The third scanning parameter includes the size of the acquisition matrix and the time resolution.

[0099] When the heart rhythm meets the preset conditions, the specific imaging process includes:

[0100] Acquire real-time movie data of multiple heartbeat cycles and respiratory cycles; the real-time movie data includes k-space data;

[0101] remapping the acquired k-space data according to a preset trigger delay to obtain a plurality of normalized heartbeat subsets;

[0102] Reconstruct the normalized heartbeat subset;

[0103] The reconstructed heartbeat subsets were ranked based on the image quality at end-expiration;

[0104] Determine a preset number of heartbeat subsets that are ranked first as target heartbeat subsets;

[0105] Non-rigidly register the reference heartbeat with a subset of target heartbeats;

[0106] Based on the average of the registered target beat subset, a cine image of cardiac function is determined.

[0107] When the heart rhythm condition does not meet the preset conditions, the third target part is scanned in real time to obtain a cardiac function movie image. In case of severe arrhythmia, cardiac movie imaging uses a single excitation and real-time compressed sensing bSSFP sequence.

[0108] When scanning the third target part when the heart rhythm of the detected object meets the preset conditions, by setting the acquisition matrix and time resolution of corresponding size under different heart rates of the detected object, it is possible to obtain a cardiac function movie image that meets the quality requirements under each heart rate without causing the imaging time to be too long. Different schemes are adopted according to the heart rhythm conditions to ensure that images can be stably acquired in all situations.

[0109] The cardiac function movie imaging in this process is performed in a free breathing state and adapts to different heart rhythm and heart rate scenarios. When facing severe arrhythmias, such as rapid atrial fibrillation and frequent premature ventricular contractions, a compressed sensing real-time movie imaging sequence is used. For other scenarios, that is, non-serious arrhythmias or sinus rhythm, the above-mentioned compressed sensing multiple average motion correction movie sequence is used. This sequence collects data from multiple heartbeats, scores each heartbeat data, and rejects the data with the lower ranking, so a small amount of arrhythmias can be rejected. By optimizing the sequence parameters, balancing the time resolution, spatial resolution and compressed sensing acceleration factor, a scale of different fast and slow heart rates and parameters is established. The heart rate range covered by this scale is from <50 beats / minute to >130 beats / minute, covering all clinical heart rate scenarios.

[0110] S206: Determine whether there is a problem with the valve of the test object; if so, proceed to S207, if not, proceed to S208.

[0111] S207: Perform phase contrast blood flow imaging on the fifth target site.

[0112] In this embodiment, the target part also includes: a fifth target part; the fifth target part includes: four chamber positions and left ventricular outflow tract positions, and the cross section above the aortic root can be selected. Correspondingly, after scanning the third target part to obtain a cardiac function movie image, and before scanning the fourth target part based on the fourth scanning parameter, the method also includes: when there is a problem with the valve of the test object, performing a phase contrast blood flow image on the fifth target part. This step selectively performs a phase contrast blood flow image based on clinical needs to ensure the comprehensiveness of the examination.

[0113] This step selectively performs phase contrast blood flow imaging based on clinical needs, and averages the phase contrast velocity coding sequence multiple times during free breathing. The multiple averaging method is used to improve the signal-to-noise ratio and suppress respiratory artifacts. By optimizing the sequence parameters, balancing the time resolution, spatial resolution, and parallel acquisition acceleration factor, the acquisition time can be controlled within 30 seconds.

[0114] S208: Scanning a fourth target site based on a fourth scanning parameter to obtain a delayed enhancement image.

[0115] The delayed enhancement images include single-excitation delayed enhancement images and high-resolution motion-corrected delayed enhancement images; the fourth target parts corresponding to the single-excitation delayed enhancement images include: four-cavity positions, two-cavity positions and a group of parallel multi-layer short-axis positions; the fourth target parts corresponding to the high-resolution motion-corrected delayed enhancement images include: two-cavity positions, four-cavity positions and a group of parallel multi-layer short-axis positions.

[0116] Single-shot delayed enhancement imaging is a SS phase-sensitive inversion recovery rapid gradient echo sequence. High-resolution motion-corrected delayed enhancement imaging is a SS multiple-average motion-corrected phase-sensitive inversion recovery bSSFP sequence. Different time resolutions are set according to the heart rate. Single-shot has no respiratory motion artifacts, bSSFP pulse acquisition, multiple averaging methods improve the signal-to-noise ratio, and motion correction technology is used to ensure the accuracy of the data. By optimizing the sequence parameters, balancing the time resolution, spatial resolution, and parallel acquisition acceleration factor, the sequence is adapted to fast and slow heart rate scenarios, and the data acquisition window is controlled within the relative static period of the cardiac cycle.

[0117] The fourth scanning parameter includes the size of the acquisition matrix and the time resolution. When scanning the fourth target part, by setting the acquisition matrix and time resolution of corresponding size at different heart rates of the detected object, delayed enhanced images that meet the quality requirements can be obtained at each heart rate without causing excessive imaging time.

[0118] S209: After the contrast agent is injected, the first target site is scanned based on the fifth scanning parameter to obtain a second longitudinal relaxation time quantitative image.

[0119] The fifth scanning parameter includes the size of the acquisition matrix, the number of recovery heartbeats after the first inversion pulse to complete data acquisition, and the number of recovery heartbeats after the second inversion pulse to complete data acquisition.

[0120] The longitudinal relaxation time quantitative imaging after contrast agent injection (i.e. Post T1 Mapping) is a MOLLI sequence with the same resolution, field of view, and layer positioning as Pre T1 Mapping. For different heart rate scenarios, the temporal resolution, spatial resolution, and inversion recovery heart rate are weighed, and different heart rate ranges correspond to different parameter settings.

[0121] When scanning the first target part and obtaining the second longitudinal relaxation time quantitative image, by setting the acquisition matrix of corresponding size and restoring the heart rate at different heart rates of the detected object, the second longitudinal relaxation time quantitative image that meets the quality requirements can be obtained at each heart rate without taking too long.

[0122] S210: Determine whether the detected object is tolerant; if so, proceed to S211, if not, proceed to S212.

[0123] S211: Scan the corresponding target part to obtain a coronary artery image and / or a four-dimensional blood flow image.

[0124] After obtaining the second longitudinal relaxation time quantitative image, the inspection process takes about 20 minutes. Then, it can be determined whether the test subject can tolerate it. According to clinical needs, it is decided whether to add coronary artery (compressed sensing whole heart coronary artery image based on image navigation) and / or 4D FLOW imaging (compressed sensing whole heart four-dimensional blood flow image based on diaphragm navigation) to ensure the comprehensiveness of the inspection. Specifically, the tolerance state of the test subject is first determined. If the test subject tolerates it, the corresponding target part is scanned to obtain the coronary artery image and / or 4D FLOW image.

[0125] The navigation efficiency of coronary artery imaging is 100%, which improves the scanning success rate. The imaging time is about 5 minutes. The image navigation positioning is simple, omitting the complicated steps of the original diaphragm navigation positioning. The navigation efficiency is 100%, which improves the scanning success rate. The application of compressed sensing acceleration technology greatly improves the imaging speed.

[0126] 4D FLOW imaging applies three orthogonal flow encoding gradient fields to any voxel in the three-dimensional imaging volume to obtain the velocity magnitude and direction of any point in space, and remove the positioning restriction of blood flow direction during positioning. The navigation efficiency is 60-80%, and the actual imaging time is about 5 minutes. The application of compressed sensing technology improves the imaging speed and ensures the coverage volume and time-space resolution.

[0127] S212: Scanning completed.

[0128] In the past, the single scanning parameter solution may cause inaccurate data when facing an increase in heart rate because relaxation has not been fully and effectively recovered. Setting a recovery time that is too long will cause each imaging time to be too long. The T1 mapping and T2 mapping in the embodiment of the present application optimize the sequence parameters, balance the time resolution, spatial resolution, parallel acquisition acceleration factor, and inversion recovery heart rate, and establish a scale for different fast and slow heart rates and scanning parameters. The heart rate range covered by this scale is from <50 beats / minute to >130 beats / minute, covering all heart rate scenarios from bradycardia to tachycardia.

[0129] Here, different recovery heartbeat numbers and acquisition matrices are set for different heart rate intervals, and a correspondence table for different scanning stages is provided. It should be noted that the correspondence in the table is only one example of the present application and does not limit other schemes.

[0130] Table 1 Correspondence between heart rate intervals and scanning parameters in the Pre T1 Mapping stage

[0131]

[0132] Table 2 Correspondence between heart rate intervals and scanning parameters in the Post T1 Mapping stage

[0133]

[0134] Table 3 Correspondence between heart rate intervals and scanning parameters in the T2 Mapping stage

[0135]

[0136] Table 4 Correspondence between heart rate intervals and scanning parameters during movie stages

[0137]

[0138] Table 5 Correspondence between heart rate intervals and scanning parameters in the delayed enhancement phase

[0139]

[0140] Conventional cardiac magnetic resonance imaging requires the patient to hold his breath multiple times, while the fully free-breathing cardiac magnetic resonance imaging technology provided in the embodiments of the present application has a wide range of applications and strong operability. It eliminates the burden of breath-holding for patients and solves the respiratory artifacts caused by poor breath-holding in previous conventional sequences. Fully free breathing also eliminates the breath-holding commands and breath-holding intervals in previous scans, as well as the time for repeated training and repeated scanning due to poor breath-holding, greatly shortening the total imaging time. In addition, by adding conditional judgments during scanning, appropriate scanning parameters and scanning sequences are selected for different heart rhythm and heart rate scenarios, which reduces the technical requirements of magnetic resonance scanning personnel, improves the success rate of inspections, and expands application scenarios.

[0141] In order to solve the above technical problems, the present application also provides a cardiac magnetic resonance full-free breathing examination device. Figure 3 The schematic diagram of the structure of the cardiac magnetic resonance full-free breathing examination device provided in the embodiment of the present application is shown. Figure 3 As shown, the device includes the following modules:

[0142] An acquisition module 301 is used to acquire multiple target parts of the detection object and acquire the current heart rate of the detection object in real time;

[0143] The determination module 302 is used to determine, for each scanning stage in the cardiac magnetic resonance scanning process, scanning parameters corresponding to the corresponding scanning stage based on the current heart rate of the detected object; the scanning parameters include at least any one or any combination of the following: the size of the acquisition matrix, the number of restored heartbeats, and the time resolution of the movie sequence; the size of the acquisition matrix and the time resolution are both negatively correlated with the current heart rate of the detected object, and the number of restored heartbeats is positively correlated with the current heart rate of the detected object;

[0144] The scanning module 303 is used to scan the corresponding target part based on the scanning parameters of each scanning stage to obtain a cardiac magnetic resonance image of the detection object.

[0145] The device provided in the embodiment of the present application is the same as the method in the above embodiment, so both have the same embodiments and beneficial effects, which will not be repeated here.

[0146] Figure 4 FIG. 1 is a schematic diagram showing the hardware structure of a cardiac magnetic resonance free breathing examination device provided in an embodiment of the present application. Figure 4 As shown, the cardiac magnetic resonance full-free breathing examination device may include a processor 401 and a memory 402 storing computer program instructions.

[0147] Specifically, the processor 401 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0148] The memory 402 may include a large capacity memory for data or instructions. By way of example and not limitation, the memory 402 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. In appropriate cases, the memory 402 may include a removable or non-removable (or fixed) medium. In appropriate cases, the memory 402 may be inside or outside the integrated gateway disaster recovery device. In a specific embodiment, the memory 402 is a non-volatile solid-state memory.

[0149] The memory 402 may include read-only memory (ROM), random access memory (RAM), magnetic disk storage media devices, optical storage media devices, flash memory devices, electrical, optical or other physical / tangible memory storage devices. Thus, in general, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., memory devices) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the method according to an aspect of the present disclosure.

[0150] The processor 401 reads and executes the computer program instructions stored in the memory 402 to implement any one of the cardiac magnetic resonance free breathing examination methods in the above embodiments.

[0151] In one example, the cardiac magnetic resonance full free breathing examination device may further include a communication interface 403 and a bus 404. The processor 401, the memory 402, and the communication interface 403 are connected via the bus 404 and communicate with each other.

[0152] The communication interface 403 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0153] Bus 404 includes hardware, software or both, and couples the components of the cardiac magnetic resonance full free breathing examination device to each other. For example, but not limitation, the bus may include an accelerated graphics port (AGP) or other graphics bus, an enhanced industrial standard architecture (EISA) bus, a front-side bus (FSB), a hypertransport (HT) interconnect, an industrial standard architecture (ISA) bus, an infinite bandwidth interconnect, a low pin count (LPC) bus, a memory bus, a microchannel architecture (MCA) bus, a peripheral component interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a serial advanced technology attachment (SATA) bus, a video electronics standard association local (VLB) bus or other suitable buses or a combination of two or more of these. Where appropriate, bus 404 may include one or more buses. Although the present application embodiment describes and shows a specific bus, the present application considers any suitable bus or interconnect.

[0154] In addition, in combination with the cardiac magnetic resonance free breathing examination method in the above embodiment, the embodiment of the present application can provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when the computer program instructions are executed by the processor, any one of the cardiac magnetic resonance free breathing examination methods in the above embodiment is implemented.

[0155] An embodiment of the present application also provides a computer program product, including a computer program, which, when processed and executed, implements any one of the cardiac magnetic resonance free breathing examination methods in the above embodiments.

[0156] It should be clear that the present application is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application.

[0157] The functional blocks shown in the structural block diagram above can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application-specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present application are programs or code segments used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link by a data signal carried in a carrier. "Machine-readable medium" may include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROMs, flash memories, erasable ROMs (EROMs), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0158] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiment, or in a different order from the embodiment, or several steps can be performed simultaneously.

[0159] The above describes various aspects of the present disclosure with reference to the flowcharts and / or block diagrams of the cardiac magnetic resonance free breathing examination method, device, equipment and product according to the embodiments of the present disclosure. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine so that these instructions executed by the processor of the computer or other programmable data processing device enable the implementation of the functions / actions specified in one or more boxes of the flowchart and / or block diagram. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor or a field programmable logic circuit. It can also be understood that each box in the block diagram and / or flowchart and the combination of boxes in the block diagram and / or flowchart can also be implemented by dedicated hardware that performs the specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions.

[0160] The above contents are only specific implementation methods of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application.

Claims

1. A cardiac magnetic resonance free breathing examination method, characterized in that: include: Acquire multiple target parts of the detected object and acquire the current heart rate of the detected object in real time; For each scanning stage in the cardiac magnetic resonance scanning process, the scanning parameters corresponding to the scanning stage are determined based on the current heart rate of the detected object; the scanning parameters include at least any one of the following items or any combination: the size of the acquisition matrix, the number of restored heartbeats, and the time resolution; the size of the acquisition matrix is ​​negatively correlated with the current heart rate of the detected object, and the time resolution and the number of restored heartbeats are positively correlated with the current heart rate of the detected object; Scanning the corresponding target part based on the scanning parameters of each scanning phase to obtain a cardiac magnetic resonance image of the detection object; The target parts at least include: a first target part, a second target part, a third target part and a fourth target part; the first target part includes: short axis positions of the left ventricle base, middle and apex; the second target part includes: three layers of short axis positions and one layer of four chamber positions; the third target part includes: two chamber positions, four chamber positions, a group of parallel multi-layer short axis positions, left ventricular outflow tract and oblique coronal left ventricular outflow tract level; the fourth target part includes: two chamber positions, four chamber positions and a group of parallel multi-layer short axis positions; The scanning parameters at least include: a first scanning parameter, a second scanning parameter, a third scanning parameter, a fourth scanning parameter and a fifth scanning parameter; Scanning the corresponding target part based on the scanning parameters of each scanning phase to obtain a cardiac magnetic resonance image of the detection object includes: Before injecting the contrast agent, scanning the first target site based on the first scanning parameter to obtain a first longitudinal relaxation time quantitative image; Scanning the first target site based on a second scanning parameter to obtain a transverse relaxation time quantitative image; While injecting the contrast agent, scanning the second target site to obtain a first-pass perfusion image of the heart; Scanning the third target part to obtain a cardiac function movie image; scanning the third target part based on the third scanning parameter when the heart rhythm of the detected object meets a preset condition; Based on the fourth scanning parameter, scanning the fourth target part to obtain a delayed enhancement image; the delayed enhancement image includes a single-excitation delayed enhancement image and a high-resolution motion-corrected delayed enhancement image; After the contrast agent is injected, the first target site is scanned based on the fifth scanning parameter to obtain a second longitudinal relaxation time quantitative image.

2. The cardiac magnetic resonance full-free breathing examination method according to claim 1, characterized in that: The first scanning parameter includes at least the size of the acquisition matrix and the number of recovery heartbeats for which data acquisition is completed after the first inversion pulse.

3. The cardiac magnetic resonance full-free breathing examination method according to claim 1, characterized in that: The second scanning parameter at least includes the number of recovery heartbeats for which data acquisition is completed after the T2 preparation pulse.

4. The cardiac magnetic resonance full-free breathing examination method according to claim 1, characterized in that: The third scanning parameter includes the size of the acquisition matrix and the time resolution; Scanning the third target site to obtain a cardiac function movie image includes: When the heart rhythm condition satisfies the preset condition, scanning the third target part based on the acquisition matrix and the time resolution to obtain the cardiac function movie image; When the heart rhythm condition does not satisfy the preset condition, the third target site is single-excited and scanned in real time to obtain the cardiac function movie image.

5. The cardiac magnetic resonance full-free breathing examination method according to claim 4, characterized in that: When the heart rhythm condition satisfies the preset condition, scanning the third target part based on the acquisition matrix and the time resolution to obtain the cardiac function movie image includes: Acquiring real-time movie data of multiple heartbeat cycles and respiratory cycles; the real-time movie data includes k-space data; remapping the acquired k-space data according to a preset trigger delay to obtain a plurality of normalized heartbeat subsets; Reconstructing the normalized heartbeat subset; sorting the reconstructed subset of heartbeats based on end-expiratory image quality; Determine a preset number of heartbeat subsets ranked first as target heartbeat subsets; non-rigidly registering a reference heartbeat with the target heartbeat subset; The cardiac function movie image is determined based on the average value of the registered target heartbeat subset.

6. The cardiac magnetic resonance full-free breathing examination method according to claim 1, characterized in that: The fourth scanning parameters include the size of the acquisition matrix and the time resolution.

7. The cardiac magnetic resonance free breathing examination method according to claim 1, characterized in that: The fifth scanning parameter includes the size of the acquisition matrix, the number of recovery heartbeats after the first inversion pulse when data acquisition is completed, and the number of recovery heartbeats after the second inversion pulse when data acquisition is completed.

8. The cardiac magnetic resonance free breathing examination method according to any one of claims 1 to 7, characterized in that: After the contrast agent is injected, the first target site is scanned based on the fifth scanning parameter to obtain a second longitudinal relaxation time quantitative image, the method further includes: Determining a tolerance state of the detection object; When the test subject tolerates the condition, the corresponding target part is scanned to obtain a compressed sensing whole-heart coronary image based on image navigation and / or a compressed sensing whole-heart four-dimensional blood flow image based on diaphragm navigation.

9. The cardiac magnetic resonance free breathing examination method according to claim 8, characterized in that: The target site also includes: a fifth target site; the fifth target site includes: a four-chamber position and a left ventricular outflow tract position; After scanning the third target part to obtain a cardiac function movie image and before scanning the fourth target part based on the fourth scanning parameter, the method further includes: In the case where there is a problem with the valve of the detection object, a phase contrast blood flow image is taken for the fifth target site.

10. A cardiac magnetic resonance full-free breathing examination device, characterized in that: The device comprises: An acquisition module, used to acquire multiple target parts of the detection object and to acquire the current heart rate of the detection object in real time; A determination module, for determining, for each scanning stage in the cardiac magnetic resonance scanning process, scanning parameters corresponding to the scanning stage based on the current heart rate of the detection object; the scanning parameters include at least any one of the following or any combination: the size of the acquisition matrix, the number of restored heartbeats, and the time resolution; the size of the acquisition matrix is ​​negatively correlated with the current heart rate of the detection object, and the time resolution and the number of restored heartbeats are positively correlated with the current heart rate of the detection object; A scanning module, configured to scan the corresponding target part based on the scanning parameters of each scanning phase, so as to obtain a cardiac magnetic resonance image of the detection object; The target parts at least include: a first target part, a second target part, a third target part and a fourth target part; the first target part includes: short axis positions of the left ventricle base, middle and apex; the second target part includes: three layers of short axis positions and one layer of four chamber positions; the third target part includes: two chamber positions, four chamber positions, a group of parallel multi-layer short axis positions, left ventricular outflow tract and oblique coronal left ventricular outflow tract level; the fourth target part includes: two chamber positions, four chamber positions and a group of parallel multi-layer short axis positions; The scanning parameters at least include: a first scanning parameter, a second scanning parameter, a third scanning parameter, a fourth scanning parameter and a fifth scanning parameter; The scanning module is specifically used for: Before injecting the contrast agent, scanning the first target site based on the first scanning parameter to obtain a first longitudinal relaxation time quantitative image; Scanning the first target site based on a second scanning parameter to obtain a transverse relaxation time quantitative image; While injecting the contrast agent, scanning the second target site to obtain a first-pass perfusion image of the heart; Scanning the third target part to obtain a cardiac function movie image; scanning the third target part based on the third scanning parameter when the heart rhythm of the detected object meets a preset condition; Based on the fourth scanning parameter, scanning the fourth target part to obtain a delayed enhancement image; the delayed enhancement image includes a single-excitation delayed enhancement image and a high-resolution motion-corrected delayed enhancement image; After the contrast agent is injected, the first target site is scanned based on the fifth scanning parameter to obtain a second longitudinal relaxation time quantitative image.

11. A cardiac magnetic resonance full-free breathing examination device, characterized in that: The device comprises: a processor and a memory storing computer program instructions; When the processor executes the computer program instructions, the cardiac magnetic resonance full-free breathing examination method as described in any one of claims 1 to 9 is implemented.

12. A computer program product, characterized in that When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes the cardiac magnetic resonance free breathing examination method as described in any one of claims 1 to 9.

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