JP2006087626A - Magnetic resonance imaging apparatus, magnetic resonance data processor, magnetic resonance data processing method and magnetic resonance data processing program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic resonance imaging apparatus capable of providing information of blood flow dynamic phase to the cardiac muscle without using an electrocardiographic signal. <P>SOLUTION: This magnetic resonance imaging apparatus executes an image reconstruction using magnetic resonance signals obtained by an asynchronous multislice dynamic imaging without using electrocardiographic synchronization, acquires a plurality of MR images for every time phase related to a plurality of sections corresponding to sequential change in high-frequency pulse frequencies, develop the heart of a subject in the MR image of the same time phase by dividing it into a plurality of small areas, generates a development showing a mean value of pixel values in the small areas for every time phase respectively, and sequentially displays the development for every time phase, for example, in time series. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for acquiring diagnostic information regarding myocardial blood flow dynamics without using electrocardiographic synchronization in myocardial perfusion imaging using a magnetic resonance imaging apparatus.

  A magnetic resonance imaging apparatus utilizes a phenomenon in which energy of a high-frequency magnetic field rotating at a specific frequency is resonantly absorbed when a group of nuclei having a specific magnetic moment is placed in a uniform static magnetic field. It is a device that visualizes chemical and physical microscopic information of a substance or observes a chemical shift spectrum.

  In the diagnosis of ischemic heart disease, left ventricular short-axis multi-slice dynamics in which contrast medium is injected from a vein and electrocardiographic synchronization is used in the initial circulation as a method of evaluating myocardial blood flow dynamics with a magnetic resonance imaging device There is a method (myocardial perfusion) of performing T1-weighted imaging and observing the myocardial contrast process. The result obtained by this myocardial perfusion is the continuous display (cine display) of each slice in the time direction, and each slice of the left ventricular short axis is divided into a plurality of radial areas, and the signal value in each divided area A developed view of various measured values obtained from a time-dependent graph (dynamic curve) in a concentric circle from the heart to the apex corresponding to a color map or gray scale, so-called Bull's eye image It is converted, displayed, and evaluated (for example, see Non-Patent Documents 1, 2, and 3).

  However, in order to obtain an electrocardiographic waveform, it takes time and effort to attach an electrode for detecting an electrocardiogram signal to the subject prior to the examination. It takes time to redo. Furthermore, the induction of gradient magnetic field switching noise for magnetic resonance imaging to an electrocardiographic waveform may cause inconvenience such as poor synchronization and poor image quality.

  In addition, since a high frequency pulse for magnetic resonance imaging is applied with the electrode attached, the high frequency pulse is induced in the electrode, the electric wire that transmits the electrocardiogram waveform, and the loop formed by the human body, which may cause a burn. . This risk is increased in high magnetic field MRI with high frequency pulse power.

Furthermore, since conventional moving image display is performed for each slice slice, it is difficult to observe the blood flow supply state of the entire myocardium at a glance.
Sakuma et al. Diagnosis of ischemic heart disease by contrast-enhanced MRI INNERVISION (15.13) 2000 PP.59-66 Nanjo et al. Evaluation of myocardial perfusion and myocardial viability INNERVISION (17.9) 2002 pp.10-14 Fujimoto et al. Points of anatomy and physiology necessary for MRI in the cardiovascular region INNERVISION (17.9) 2002 pp.1-4

  The present invention has been made in view of the above circumstances, and can provide information on blood flow dynamics to the myocardium without using an electrocardiogram signal, a magnetic resonance data processing apparatus, and a magnetic resonance data processing. It is an object to provide a method and a magnetic resonance data processing program.

  In order to achieve the above object, the present invention takes the following measures.

  According to a first aspect of the present invention, a gradient magnetic field and a high-frequency pulse are repeatedly applied to a subject placed in a static magnetic field space, and magnetism generated in the subject's heart by each application of the gradient magnetic field and the high-frequency pulse. An imaging means for performing an imaging operation for receiving a resonance signal; a control means for controlling the imaging means to sequentially change the high-frequency pulse frequency in each application of the gradient magnetic field and the high-frequency pulse; and the imaging operation. Same as image reconstruction means for performing image reconstruction using the received magnetic resonance signal and obtaining a plurality of first images for each phase with respect to a plurality of slices corresponding to the sequential change of the high frequency pulse frequency The first image in the time phase is expanded by dividing the subject's heart into a plurality of small regions, and represents a mean value of pixel values in each of the small regions. A magnetic resonance imaging apparatus comprising: image generation means for generating a development view of each time phase; and display means for displaying the first development view for each time phase in a predetermined form. is there.

  A second aspect of the present invention is based on imaging according to a pulse sequence in which a gradient magnetic field and a high-frequency pulse are repeatedly applied to a subject arranged in a static magnetic field space, and the high-frequency pulse frequency is sequentially changed. Storage means for storing magnetic resonance data obtained by collecting magnetic resonance signals generated in the heart of the subject, and image reconstruction using the magnetic resonance data to cope with sequential changes in the high-frequency pulse frequency An image reconstructing unit that obtains a plurality of first images for each time phase and a plurality of slices to be developed by dividing the heart of the subject in the first image of the same time phase into a plurality of small regions Then, an image generation means for generating a first development view representing the average value of the pixel values in each of the small regions for each time phase, and the first development view for each time phase are displayed in a predetermined form. A magnetic resonance data processing apparatus characterized by comprising a shows means.

  A third aspect of the present invention is based on imaging according to a pulse sequence in which a gradient magnetic field and a high-frequency pulse are repeatedly applied to a subject arranged in a static magnetic field space, and the high-frequency pulse frequency is sequentially changed. Image reconstruction is performed using magnetic resonance data obtained by collecting magnetic resonance signals generated in the heart of the subject, and a plurality of tomograms corresponding to the sequential change of the high-frequency pulse frequency are plural for each time phase. A first step of obtaining the first image of the subject, and developing the subject's heart in the first image in the same time phase by dividing the heart into a plurality of small regions, and the pixel values of each of the small regions A magnetic resonance data processing method comprising: a second step of generating a first development diagram representing an average value for each time phase.

  The fourth aspect of the present invention follows a pulse sequence in which a gradient magnetic field and a high-frequency pulse are repeatedly applied to a subject placed in a static magnetic field space and applied so as to sequentially change the high-frequency pulse frequency. Image reconstruction is performed using magnetic resonance data obtained by collecting magnetic resonance signals generated in the heart of the subject by imaging, and a plurality of tomograms corresponding to the sequential change of the high-frequency pulse frequency are time-phased. An image reconstruction function for obtaining a plurality of first images every time, and developing the subject's heart in the first image in the same time phase by dividing the heart into a plurality of small regions, An image generation function for generating a first development view representing an average value of pixel values for each time phase and a display function for displaying the first development view for each time phase in a predetermined form are realized. Is because the magnetic resonance data processing program.

  As described above, according to the present invention, a magnetic resonance imaging apparatus, a magnetic resonance data processing apparatus, a magnetic resonance data processing method, and a magnetic resonance data processing program that can provide blood flow dynamics information to the myocardium without using an electrocardiogram signal. Can be realized.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, components having substantially the same function and configuration are denoted by the same reference numerals, and redundant description will be given only when necessary.

  FIG. 1 is a block diagram of a magnetic resonance imaging apparatus 10 according to this embodiment. As shown in the figure, a magnetic resonance imaging apparatus 10 includes a static magnetic field magnet 11, a cooling system control unit 12, a gradient magnetic field coil 13, a high frequency probe 14, a gradient magnetic field power source 17, a transmission unit 18, a reception unit 19, and a computer system 20. The display 24 is provided.

  The static magnetic field magnet 11 is a magnet that generates a static magnetic field having an arrangement space for arranging a subject. The static magnetic field magnet 11 forms a uniform static magnetic field in the arrangement space.

  The cooling system control unit 12 controls the cooling mechanism of the static magnetic field magnet 11.

  The gradient magnetic field coil 13 is provided inside the static magnetic field magnet 11 and has a shorter axis than the static magnetic field magnet 11, and converts the pulse current supplied from the gradient magnetic field coil device power supply 17 into a gradient magnetic field. The signal generation site (position) is specified by the gradient magnetic field generated by the gradient magnetic field coil 13.

  In the present embodiment, it is assumed that the gradient magnetic field coil 13 and the static magnetic field magnet 11 are cylindrical.

  The high frequency transmission coil (RF transmission coil) 14 is a coil for applying a high frequency pulse for generating a magnetic resonance signal to the imaging region of the subject. The high-frequency transmission coil 14 is a whole-body RF coil, and can be used as a reception coil, for example, when photographing the abdomen.

  The high-frequency receiving coil (RF receiving coil) 15 is a coil for receiving magnetic resonance from the subject, which is installed so as to sandwich the subject in the vicinity of the subject, preferably in a close contact state. The high-frequency receiving coil 15 generally has a dedicated shape for each part.

  1 illustrates a cross coil system in which a high-frequency transmission coil and a high-frequency reception coil are separated from each other, but a configuration using a single coil system in which these coils are shared by one coil may be employed.

  The gradient coil device power source 17 generates a pulse current for forming a gradient magnetic field and supplies the pulse current to the gradient magnetic field coil 13. Further, the gradient coil device power source 17 controls the polarity of the gradient magnetic field by switching the direction of the pulse current supplied to the gradient magnetic field coil 13 according to the control of the control unit 202 described later.

  The transmission unit 18 includes an oscillation unit, a phase selection unit, a frequency conversion unit, an amplitude modulation unit, and a high frequency power amplification unit (each not shown), and transmits a high frequency pulse corresponding to the Larmor frequency to the transmission high frequency coil. To do. Due to the high frequency generated from the high frequency transmission coil 14 by the transmission, the magnetization of the predetermined atomic nucleus of the subject is excited.

  The receiver 19 has an amplifier, an intermediate frequency converter, a phase detector, a filter, and an A / D converter (each not shown). The receiving unit 19 amplifies the magnetic resonance signal (high frequency signal) received from the high frequency coil 15 and releases when the nuclear magnetization relaxes from the excited state to the ground state, and intermediate frequency conversion processing using the transmission frequency. , Phase detection processing, filter processing, and A / D conversion processing are performed.

  The computer system 20 includes a storage unit 201, a control unit 202, a data collection unit 203, a reconstruction unit 204, a data processing unit 205, and an input unit 207.

  The storage unit 201 stores, for each patient, magnetic resonance signal data (raw data) before reconstruction obtained via the reception unit 19, magnetic resonance image data reconstructed by the reconstruction unit 204, and the like. In addition, the storage unit 201 stores a shooting program for executing shooting sequences corresponding to various shooting methods.

  The control unit 202 includes a CPU, a memory, and the like (not shown), and controls the magnetic resonance imaging apparatus statically or dynamically as a control center of the entire system. For example, the control unit 202 reads out an imaging program corresponding to the imaging method selected via the input unit 207 from the storage unit 201, and executes overall control of the apparatus according to the program.

  The data collection unit 203 collects the digital signal (magnetic resonance signal) sampled by the reception unit 19.

  The reconstruction unit 204 performs post-processing, that is, reconstruction such as Fourier transform, on the data collected by the data collection unit 203 to obtain spectrum data or image data of a desired nuclear spin in the subject.

  The data processing unit 205 executes generation of a bullseye image based on a plurality of dynamic images in the same phase, generation of a dynamic curve, generation of a bullseye image based on the dynamic curve, and the like in asynchronous myocardial perfusion imaging described later. Each of these processes will be described in detail later.

  The display unit 24 is an output unit that displays spectrum data or image data input from the data processing unit 20.

(Electrocardiographic synchronization myocardial perfusion imaging)
First, from a viewpoint of comparison with asynchronous myocardial perfusion imaging (described later) executed by the magnetic resonance imaging apparatus 10, a general electrocardiographic synchronous myocardial perfusion imaging method will be described.

  FIG. 2 is a flowchart showing the flow of each process executed in the electrocardiographic synchronization myocardial perfusion imaging. As shown in the figure, in this imaging method, after a bolus of contrast medium is administered from a vein, the first circulation is obtained by obtaining multiple slices of the left ventricular short axis and obtaining a T1-weighted image such as the fast field echo method or EPI method. Data collection is performed by dynamic (continuous) imaging combined with electrocardiogram synchronization using a pulse sequence obtained (step S1). In the following description, each time phase in dynamic imaging is referred to as “dynamic time phase”.

  FIG. 3 is a diagram for explaining a data collection method according to electrocardiographic synchronization myocardial perfusion imaging. In this example, data collection of three slices is performed for two heartbeats, and this is repeated continuously during the first circulation. Note that an inversion pulse for applying T1 contrast is applied immediately before data collection for each slice. The data collected in this way is reconstructed, and an MR image for each slice is generated (step S2).

  FIG. 4 is a diagram showing MR images (slices 1, 2, and 3) for each tomogram obtained in each dynamic time phase by the data collection method shown in FIG. That is, 1-1, 2-1, 3-1, 1-2, 2-2, 3-2,... 1-30, 2-30, 3-30 shown in FIG. It is an acquired MR image, and shows an example in the case of a total of three slices of slices 1, 2, and 3 from the apex portion to the cusp portion and a dynamic time phase number of 30.

  Each obtained MR image is displayed as a cine for each slice position (continuous moving image display in the time direction. For example, in FIG. 3, continuous display in the order of 1-1, 1-2, 1-3). It is also possible.

  Next, the myocardium on each MR image is divided into a plurality of small regions, and a dynamic curve (a graph representing temporal changes in image values) is generated based on the average image value in each region (step S3).

  That is, the endocardial and epicardial contours are extracted from each MR image in FIG. 3, and the region sandwiched between them is divided into, for example, 100 regions (in FIG. 3, for the sake of simplicity, eight small regions are shown. And the entire left ventricular myocardium is divided into 3 × 8 = 24 small regions). An average value is obtained from the pixel values of each small area, and this is plotted in time series to create a dynamic curve for each small area. For example, the small area A will be described. The average of the pixel values of the small area A in each dynamic time phase is calculated, and the average values of the small areas A from the obtained 3-1 image to the 3-30 image are time-series. Plotting dynamically creates a dynamic curve. In the upper part of FIG. 5, the dynamic curve (left side) for the small area A and the dynamic curve (right side) for the small area A are shown.

  Next, based on each dynamic curve, a parameter value (characteristic value) representing characteristics of temporal change such as a signal maximum value, a maximum gradient, a time until the maximum gradient, an average signal value for each small region is calculated (step) S4). By mapping to the corresponding region of the concentric circle representing the entire left ventricular myocardium by mapping the value of the obtained parameter (here, two values of signal maximum value and time to maximum gradient) and color or gray scale, An image for each dynamic time phase is generated. This image is an image of the subject to be imaged (in this case, the left ventricular myocardium) developed as 24 concentric divided regions, and is called a “development view” or a “Bull's eye image” because of its form. In the display method, the developed display is called a Bull's eye display. These images and their display methods are common in other diagnostic methods such as nuclear medicine examinations, and are used for blood flow distribution evaluation of each part of the myocardium.

  In the lower part of FIG. 5, a bullseye image (left side) for the small area A and a bullseye image (right side) for the small area B are shown. In the figure, the inner side of the concentric circles corresponds to the apex and the outer side corresponds to the cusp.

(Asynchronous myocardial perfusion imaging)
Next, an asynchronous myocardial perfusion imaging method executed by the magnetic resonance imaging apparatus 10 will be described. This imaging technique provides a method for collecting data of a myocardial perfusion image that does not require ECG synchronization, a post-processing method, and a display method.

  FIG. 6 is a flowchart showing the flow of each process executed in asynchronous myocardial perfusion imaging. As shown in the figure, first, in this imaging method, data collection is executed by multi-slice dynamic imaging without requiring electrocardiogram synchronization (asynchronous) (step S21).

  FIG. 7 is a diagram illustrating an example of a scan sequence executed in the present imaging method. The pulse sequence and data collection order used for data collection are the same as in the example of FIG. 3, but the electrocardiogram waveform is not used and multi-slice dynamic (continuous) collection is performed asynchronously. .

  In the above-described electrocardiographic myocardial perfusion imaging, the number of imaging slices must be reduced enough to fit in the cardiac cycle measured before imaging in consideration of changes in the heart rate during imaging. There is. For this reason, the number of slices that can be shot is limited. On the other hand, in this asynchronous myocardial perfusion imaging, imaging is performed asynchronously to the electrocardiogram waveform. Therefore, as shown in FIG. 7, there is no R-wave trigger waiting time before imaging at the next time phase, and the number of slices that can be imaged per unit time can be increased. In addition, since data acquisition is always performed at a time determined by the pulse sequence length, there is an advantage that the dynamic time phase is always at a constant interval.

  In addition, each dynamic time phase data collected in this asynchronous myocardial perfusion imaging is an image of different cardiac time phases even in the same slice. Different from that obtained.

  FIG. 8 is a diagram showing each slice (slice 1, 2, 3) obtained in each dynamic time phase according to the scan sequence shown in FIG. In the example shown in the figure, 90 images are obtained as a result of repeating the imaging of 3 slices for 30 time phases. The image data obtained in this way is reconstructed by the reconstruction unit 204, and an MR image is generated (step S22).

Next, a bullseye image for each dynamic time phase is generated based on each image obtained by asynchronous multi-slice dynamic imaging (step S23). That is, endocardial and epicardial contours are extracted from each tomographic image at each time phase. The region between the extracted endocardium and epicardial contour is divided into, for example, 100 regions in a radial pattern (in this figure, as in the example of FIG. 4, the extracted endocardium and epicardium are divided). (The region between the contour and the contour is divided into eight small regions, and the entire left ventricular myocardium is divided into a total of 3 × 8 = 24 regions.)
The average of the image values of each divided small area is calculated, and a bull's eye image is created by expanding the entire left ventricular myocardium as shown in FIG. 9 for each dynamic time phase in association with a predetermined color or gray scale. (Step S23).

  As shown in FIG. 10, the created bull's eye image of each time phase is displayed as a continuous moving image (cine) in order of time phase, so that the change in contrast agent distribution of the entire left ventricular myocardium in the first circulation can be seen as a single image. Visualization is possible (step S24). That is, in the electrocardiographic synchronization myocardial perfusion imaging, it is necessary to individually display a plurality of slice images as moving images, and it is difficult to observe the blood flow dynamics of the entire left ventricle at a time. On the other hand, in this method, as described above, since the imaging is performed without using the electrocardiogram synchronization, even the same slice is collected in a different cardiac phase in principle. The shape is also different. However, in step S23, the myocardium of each image is divided into regions and a developed view is created, and this is continuously displayed in step S24, so that the change in the image value is visually recognized as compared with electrocardiographic synchronization myocardial perfusion imaging. Is possible.

  Next, a dynamic curve representing the time change of the signal value of each small area of the myocardium is created from the image values of the obtained bullseye images (development views) of each dynamic time phase (step 25). FIG. 11 shows an example of a dynamic curve related to the small area α of the myocardium shown in FIG. Naturally, a total of 3 × 8 = 24 dynamic curves exist together with the other remaining small areas.

Next, based on each dynamic curve, parameter values such as a signal maximum value, a maximum gradient, a time until the maximum gradient, and an average signal value in each region are calculated (step S26). By associating the calculated parameter values with colors or gray scales, it is possible to generate and display a bullseye image (development drawing) relating to each small region as shown in FIG. 12 (step S27). FIG. 12 shows an example in which the time until the maximum gradient of the dynamic curve in each region is displayed. Note that the bullseye image obtained in step S27 and its display provide information equivalent to that obtained in step S5.

  According to the configuration described above, the following effects can be obtained.

  According to this magnetic resonance imaging apparatus, multi-slice dynamic imaging is executed without using electrocardiographic synchronization, and diagnostic information relating to myocardial blood flow dynamics is generated based on this. Therefore, since an electrocardiogram synchronization signal is not required, it is not necessary to attach an electrode for detecting an electrocardiogram signal to the subject. In addition, the imaging operation is not interrupted due to a failure of the electrocardiogram synchronization signal or a change in the heart rate of the subject during imaging. As a result, it is possible to omit work such as setting the electrode to an appropriate position, and it is possible to reduce the burden on the operator and the physical burden on the subject.

  Further, according to the present magnetic resonance imaging apparatus, since the subject does not need to be equipped with an electrode, there is no risk of causing a burn by applying a high frequency pulse for imaging. As a result, it is possible to realize safe imaging and reduce the attention burden on the operator and the subject.

  Further, according to the present magnetic resonance imaging apparatus, since an electrocardiographic synchronization signal is not required, it is possible to prevent the gradient magnetic field switching noise from being induced into an electrocardiographic waveform, which causes a deterioration in image quality and a malfunction. In particular, if data of a preset number of slices cannot be collected within a planned cardiac cycle due to a failure of an electrocardiogram synchronization signal or a change in the heart rate of the subject being imaged, the result of waiting for the next R wave , The dynamic time resolution is unequal. For this reason, a desired time resolution may not be obtained, and inconveniences such as a decrease in reliability as diagnostic information may occur in observation and dynamic analysis by cine display. In the myocardial perfusion examination, since the contrast medium is used, the imaging cannot be performed again. Therefore, it is necessary to avoid as much as possible that the imaging is interrupted and the diagnosis is impossible due to the deterioration of the image quality after the contrast medium is injected. Since this magnetic resonance imaging apparatus can eliminate all the problems caused by the synchronization of electrocardiograms, it can reduce the probability of re-imaging and provide high-quality diagnostic information as compared with the prior art. Can do.

  Further, according to the present magnetic resonance imaging apparatus, multi-slice dynamic imaging is executed without using electrocardiogram synchronization, and new diagnostic information relating to myocardial blood flow dynamics is generated based on this. In particular, it can be said that a bullseye image directly obtained from an MR image obtained by multi-slice dynamic imaging and a dynamic curve generated from the bullseye image are new diagnostic information that has not existed before. Therefore, according to the present magnetic resonance imaging apparatus, new information effective for diagnosis can be provided, and it is possible to contribute to the improvement of the quality of medical practice.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Specific examples of modifications are as follows.

  (1) Each function according to the present embodiment, in particular, each function for executing asynchronous myocardial perfusion imaging, installs a program for executing the function in a computer such as a workstation and expands them on a memory. This can also be realized. At this time, a program capable of causing the computer to execute the technique is stored in a recording medium such as a magnetic disk (floppy (registered trademark) disk, hard disk, etc.), an optical disk (CD-ROM, DVD, etc.), or a semiconductor memory. It can also be distributed.

  (2) In the above embodiment, the magnetic resonance imaging apparatus including the imaging system has been described as an example. However, the imaging system is not necessarily required, for example, image data obtained by asynchronous multi-dynamic imaging (not limited to before and after image reconstruction) is stored in advance, and based on this, data is acquired later in asynchronous myocardial perfusion imaging. The present invention can also be realized by a magnetic resonance data processing apparatus (image processing apparatus) capable of performing processing and display.

  In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  As described above, according to the present invention, a magnetic resonance imaging apparatus, a magnetic resonance data processing apparatus, a magnetic resonance data processing method, and a magnetic resonance data processing program that can provide blood flow dynamics information to the myocardium without using an electrocardiogram signal. Can be realized.

FIG. 1 is a block diagram of a magnetic resonance imaging apparatus 10 according to this embodiment. FIG. 2 is a flowchart showing the flow of each process executed in the electrocardiographic synchronization myocardial perfusion imaging. FIG. 3 is a diagram for explaining a data collection method according to electrocardiographic synchronization myocardial perfusion imaging. FIG. 4 is a diagram showing each tomogram (slice 1, 2, 3) obtained in each dynamic time phase according to the scan sequence shown in FIG. The upper part of FIG. 5 shows a dynamic curve (left side) for the small area A and a dynamic curve (right side) for the small area A, respectively. The lower part of FIG. 5 shows the bullseye image (left side) for the small region A and the bullseye image (right side) for the small region B, respectively. FIG. 6 is a flowchart showing the flow of each process executed in asynchronous myocardial perfusion imaging. FIG. 7 is a diagram showing an example of a scan sequence executed in asynchronous myocardial perfusion imaging. FIG. 8 is a diagram showing each slice (slice 1, 2, 3) obtained in each dynamic time phase according to the scan sequence shown in FIG. FIG. 9 is a diagram showing a bullseye image in each time phase based on an MR image obtained by asynchronous multi-slice dynamic imaging. FIG. 10 is a diagram for explaining the cine display of the bullseye image shown in FIG. FIG. 11 is a diagram showing an example of a dynamic curve related to the small area α of the myocardium shown in FIG. FIG. 12 is a diagram showing a bullseye image based on a dynamic curve obtained in asynchronous myocardial perfusion imaging.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Magnetic resonance imaging apparatus, 11 ... Static magnetic field magnet, 12 ... Cooling system control part, 13 ... Gradient magnetic field coil, 14 ... High frequency probe, 16 ... Shim coil power supply, 17 ... Gradient magnetic field power supply, 18 ... Transmission part, 19 ... Reception 20 ... computer system 24 ... display 201 ... storage unit 202 ... control unit 203 ... data collection unit 204 ... reconstruction unit 205 ... data processing unit 207 ... input unit

Claims (8)

An imaging operation is performed in which a gradient magnetic field and a high-frequency pulse are repeatedly applied to a subject placed in a static magnetic field space, and a magnetic resonance signal generated in the heart of the subject is received by each application of the gradient magnetic field and the high-frequency pulse. Photographing means to
In each application of the gradient magnetic field and the high frequency pulse, control means for controlling the imaging means so as to sequentially change the high frequency pulse frequency;
Image reconstruction is performed using the magnetic resonance signal received by the imaging operation, and a plurality of first images are obtained for each time phase with respect to a plurality of tomograms corresponding to the sequential change of the high-frequency pulse frequency. Means,
The heart of the subject in the first image of the same temporal phase is developed by dividing it into a plurality of small regions, and a first development view showing an average value of pixel values in each of the small regions is displayed for each time phase. Image generating means for generating
Display means for displaying the first development view for each time phase in a predetermined form;
A magnetic resonance imaging apparatus comprising:   2. The magnetic resonance imaging apparatus according to claim 1, further comprising diagnostic information generation means for generating diagnostic information based on the first development view for each time phase. The diagnostic information generation unit generates a dynamic curve indicating temporal change of an average value of pixel values in at least one of the plurality of small regions based on the first development view for each time phase,
The display means displays the dynamic curve generated by the diagnostic information generation means;
The magnetic resonance imaging apparatus according to claim 1, wherein: The diagnostic information generating means includes
Based on the first development view for each time phase, in each of the plurality of small regions, a dynamic curve indicating a temporal change in the average value of the pixel values is generated,
Based on the generated dynamic curve in the plurality of small regions, the signal maximum value, maximum gradient, time to maximum gradient, average signal value and other characteristic values of each small region are calculated,
A second development diagram representing the characteristic value in each of the small regions is generated for each time phase,
The display means displays the second development view for each time phase calculated by the diagnostic information generation means;
The magnetic resonance imaging apparatus according to claim 1, wherein:   5. The display unit according to claim 1, wherein the display unit continuously displays the first development view for each time phase or the second development view for each time phase according to a time series. A magnetic resonance imaging apparatus according to claim 1. Magnetism generated in the heart of the subject by imaging in accordance with a pulse sequence in which a gradient magnetic field and a high-frequency pulse are repeatedly applied to a subject placed in a static magnetic field space, and the high-frequency pulse frequency is sequentially changed. Storage means for storing magnetic resonance data obtained by collecting resonance signals;
An image reconstruction unit that performs image reconstruction using the magnetic resonance data, and obtains a plurality of first images for each time phase with respect to a plurality of slices corresponding to the sequential change of the high-frequency pulse frequency;
The heart of the subject in the first image of the same temporal phase is developed by dividing it into a plurality of small regions, and a first development view showing an average value of pixel values in each of the small regions is displayed for each time phase. Image generating means for generating
Display means for displaying the first development view for each time phase in a predetermined form;
A magnetic resonance data processing apparatus comprising: Magnetism generated in the heart of the subject by imaging in accordance with a pulse sequence in which a gradient magnetic field and a high-frequency pulse are repeatedly applied to a subject placed in a static magnetic field space and the high-frequency pulse frequency is sequentially changed. First, image reconstruction is executed using magnetic resonance data obtained by collecting resonance signals, and a plurality of first images are obtained for each time phase with respect to a plurality of slices corresponding to sequential changes in the high-frequency pulse frequency. And the steps
The heart of the subject in the first image of the same temporal phase is developed by dividing it into a plurality of small regions, and a first development view showing an average value of pixel values in each of the small regions is displayed for each time phase. A second step of generating
A magnetic resonance data processing method comprising: On the computer,
Magnetism generated in the heart of the subject by imaging in accordance with a pulse sequence in which a gradient magnetic field and a high-frequency pulse are repeatedly applied to a subject placed in a static magnetic field space and the high-frequency pulse frequency is sequentially changed. Image reconstruction is performed using magnetic resonance data obtained by collecting resonance signals, and image reconstruction is performed to obtain a plurality of first images for each phase with respect to a plurality of slices corresponding to the sequential change of the high-frequency pulse frequency. Configuration functions;
The heart of the subject in the first image of the same temporal phase is developed by dividing it into a plurality of small regions, and a first development view showing an average value of pixel values in each of the small regions is displayed for each time phase. An image generation function to generate
A display function for displaying the first development view for each time phase in a predetermined form;
A magnetic resonance data processing program for realizing.

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