KR102601861B1 - Magnetic resonance imaging generating apparatus and method for acquiring blood vessel wall image - Google Patents

Abstract

The present invention relates to a magnetic resonance image generating device for obtaining clearer images of blood vessel walls, comprising: a control unit providing a pre-applied pulse train whose excitation angle is adjusted according to the speed of the tissue of an object to an MRI scanner; and the pre-applied pulse train. It includes an image processing unit that generates a blood vessel wall-enhanced image from magnetic resonance image signals obtained according to the applied pulse train. At this time, the control unit provides a pre-applied pulse train including a B1 magnetic field and a gradient magnetic field designed so that the lower the tissue velocity, the smaller the applied angle, and the higher the tissue velocity, the larger the applied angle.

Description

Magnetic resonance image generating apparatus and method for acquiring blood vessel wall images {MAGNETIC RESONANCE IMAGING GENERATING APPARATUS AND METHOD FOR ACQUIRING BLOOD VESSEL WALL IMAGE}

The present invention relates to a magnetic resonance image generating device and a magnetic resonance image generating method for obtaining images of blood vessel walls.

Medical imaging methods for diagnosing vascular diseases have mainly relied on lumen imaging. However, this has the limitation of not being able to directly observe the fundamental pathological process that begins in the blood vessel wall, so an imaging technique that directly depicts the blood vessel wall is required.

The most important image contrast condition in blood vessel wall imaging is to maximize the contrast-to-noise ratio between the blood vessel wall and the lumen by keeping the lumen blood flow signal as small as possible and the surrounding blood vessel wall signal as large as possible. . Magnetic resonance imaging is a medical imaging method that is in the spotlight because it does not involve radiation exposure, but gadolinium-based contrast agents commonly used in vascular imaging have the problem of causing a side effect called nephrogenic systemic fibrosis.

Accordingly, the present invention seeks to provide a magnetic resonance image generating device and method that can obtain high-definition images of blood vessel walls while suppressing images of blood flow as much as possible without using contrast agents in order to minimize side effects caused by the use of contrast agents.

The present invention uses a preparatory excitation pulse sequence, which is one of the techniques used to generate specific image contrast in magnetic resonance imaging techniques. The design of a general pre-applied pulse train is made on the assumption that the human tissue does not move. In the present invention, in order to set the tissue speed as the main input parameter, the effect of the blood flow speed value on the application result is theoretically formulated to image the blood vessel wall. We propose a method to design an applied pulse train to generate contrast.

Republic of Korea Patent No. 10-1334064 (Title of invention: Motion estimation method and device in vascular images)

The present invention is intended to solve the problems of the prior art described above, and the purpose of some embodiments of the present invention is to provide a method and device for generating a magnetic resonance image that can provide image contrast that emphasizes the blood vessel wall.

However, the technical challenge that this embodiment aims to achieve is not limited to the technical challenges described above, and other technical challenges may exist.

As a technical means for achieving the above-described technical problem, the magnetic resonance image generating device according to the first aspect of the present invention provides a pre-applied pulse train whose excitation angle is adjusted according to the speed of the tissue of the object with respect to the MRI scanner. It includes a control unit that generates a blood vessel wall-enhanced image from a magnetic resonance image signal obtained according to the pre-applied pulse train and an image processing unit that generates a blood vessel wall-emphasized image. At this time, the control unit provides a pre-applied pulse train including a B1 magnetic field and a gradient magnetic field designed so that the lower the tissue velocity, the smaller the applied angle, and the higher the tissue velocity, the larger the applied angle.

In addition, the method of generating a magnetic resonance image using a magnetic resonance image generating device according to the second aspect of the present invention includes providing a pre-applied pulse string to an MRI scanner whose application angle is adjusted according to the speed of the tissue of the object, and the pre-applied pulse train. It includes generating a blood vessel wall-emphasized image from magnetic resonance image signals acquired according to the pulse train. At this time, the pre-applied pulse train includes a B1 magnetic field and a gradient magnetic field designed so that the lower the tissue velocity, the smaller the applied angle, and the higher the tissue velocity, the larger the applied angle.

According to the means for solving the problems of the present invention described above, the present invention makes it possible to obtain an MRI image that can clearly display the blood vessel wall while suppressing the signal of the blood vessel lumen. In this way, precise diagnosis of vascular disease lesions is possible by obtaining high-definition images of blood vessel walls that allow for a detailed examination of abnormal signs occurring in blood vessel walls without any risk of radiation exposure or side effects from the use of contrast media.

1 is a block diagram overall showing a magnetic resonance image generating device according to an embodiment of the present invention.
Figure 2 is a diagram illustrating an image in which the blood vessel wall is emphasized, which the present invention seeks to obtain.
Figure 3 is a flowchart showing a method of generating a magnetic resonance image for obtaining an image of a blood vessel wall according to an embodiment of the present invention.
Figure 4 is a timing diagram showing a method for generating a magnetic resonance image according to an embodiment of the present invention.
Figure 5 is a diagram for explaining the Fourier transform equation to be used in the design of the speed selection pre-applied pulse according to an embodiment of the present invention.
Figure 6 shows an example of a speed selection pre-applied pulse according to an embodiment of the present invention.
Figure 7 is a diagram illustrating the weight accumulated in k-space by a speed selection pre-applied pulse applied according to an embodiment of the present invention.
Figure 8 is a diagram showing Mxy and Mz values generated by a speed selection pre-applied pulse according to an embodiment of the present invention.
Figure 9 shows an example of a speed selection pre-applied pulse according to another embodiment of the present invention.
Figure 10 shows a blood vessel wall image obtained using a velocity-selective pre-applied pulse train according to an embodiment of the present invention.

Below, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts that are not related to the description are omitted, and similar parts are given similar reference numerals throughout the specification.

Throughout the specification, when a part is said to be "connected" to another part, this includes not only the case where it is "directly connected," but also the case where it is "electrically connected" with another element in between. . Additionally, when a part "includes" a certain component, this means that it may further include other components rather than excluding other components, unless specifically stated to the contrary.

In this specification, “Magnetic Resonance Imaging (MRI) device” refers to a magnetic field and non-ionizing radiation (radio high frequency) applied to an object to obtain an image based on the physical principle of nuclear magnetic resonance (NMR). It refers to the device that authorizes.

Additionally, “image” or “image” refers to multi-dimensional data composed of discrete elements, such as a plurality of pixels in a two-dimensional image and a plurality of voxels in a three-dimensional image. It means composed of .

Additionally, an “object” is something that is subject to imaging by a magnetic resonance imaging device and may include a person, an animal, or a part thereof. Additionally, the object may include various organs such as the heart, brain, or blood vessels, or various types of phantoms.

Additionally, the “user” may be a medical professional, such as a doctor, nurse, medical imaging specialist, or device repair technician, but is not limited thereto.

Additionally, “pulse sequence (or pulse train)” refers to a signal repeatedly applied from a magnetic resonance imaging device. The pulse sequence may include repetition time (TR) or echo time (Time to Echo, TE) as time parameters of the RF pulse.

Hereinafter, embodiments of a magnetic resonance imaging device will be described with reference to the attached drawings.

Figure 1 is a block diagram showing the overall magnetic resonance image generating apparatus according to an embodiment of the present invention.

The magnetic resonance image generating device 1 may include an MRI scanner 10, a signal processing unit 20, a control unit 40, a monitoring unit 50, and an interface unit 60.

The MRI scanner 10 forms a magnetic field and generates a resonance phenomenon for atomic nuclei, and a magnetic resonance image is captured while the object is located inside the MRI scanner 10. The MRI scanner 10 includes a main magnet 12, a gradient coil 14, an RF coil 16, etc., through which a static magnetic field and a gradient magnetic field are formed, and an RF signal is irradiated toward the object.

The main magnet 12, gradient coil 14 and RF coil 16 are arranged within the MRI scanner 10 according to a preset direction. An object is positioned on a table that can be inserted into the cylinder along the horizontal axis of the cylinder, and as the table moves, the object can be positioned inside the bore of the MRI scanner 10.

The main magnet 12 generates a static magnetic field that aligns the magnetic dipole moments of atomic nuclei included in the object in a certain direction.

The gradient coil 14 includes an The gradient coil 14 induces different resonance frequencies for each part of the object, allowing location information of each part of the object to be obtained.

The RF coil 16 may irradiate an RF signal to an object and receive a magnetic resonance image signal emitted from the object. The RF coil 16 may output an RF signal of the same frequency as the frequency of precession toward the atomic nucleus undergoing precession, and then receive a magnetic resonance image signal emitted from the object.

For example, the RF coil 16 generates an RF signal with a frequency corresponding to the atomic nucleus and applies it to the object in order to transition the atomic nucleus from a low energy state to a high energy state. Afterwards, when the RF coil 16 stops transmitting the RF signal, the atomic nucleus to which the electromagnetic wave was applied transitions from a high energy state to a low energy state and radiates an electromagnetic wave having a Larmor frequency, and the RF coil 16 Receive the corresponding electromagnetic wave signal.

The RF coil 16 includes a transmitting RF coil that transmits an RF signal having a radio frequency corresponding to the type of atomic nucleus and a receiving RF coil that receives electromagnetic waves radiated from the atomic nucleus.

Additionally, the RF coil 16 may be fixed to the MRI scanner 10 or may be removable. The detachable RF coil 16 may be implemented in the form of a head RF coil, chest RF coil, leg RF coil, neck RF coil, shoulder RF coil, wrist RF coil, and ankle RF coil that can be coupled to a part of the object. You can.

The MRI scanner 10 can provide various information to a user or object through a display, and may include a display 18 disposed on the outside and a display (not shown) disposed on the inside.

The signal processing unit 20 may control a gradient magnetic field formed inside the MRI scanner 10 according to a predetermined MR pulse sequence (i.e., pulse train) and control transmission and reception of RF signals and magnetic resonance image signals.

The signal processing unit 20 may include a gradient magnetic field amplifier 22, a switching unit 24, an RF transmitting unit 26, and an RF receiving unit 28.

The gradient amplifier 22 drives the gradient coil 14 included in the MRI scanner 10, and sends a pulse signal that generates a gradient magnetic field under the control of the gradient magnetic field controller 44 to the gradient coil 14. supply to. By controlling the pulse signal supplied from the gradient magnetic field amplifier 22 to the gradient coil 14, gradient magnetic fields in the X-axis, Y-axis, and Z-axis directions can be synthesized.

The RF transmitter 26 supplies RF pulses to the RF coil 16 to drive the RF coil 16. The RF receiver 28 receives the magnetic resonance image signal received and transmitted by the RF coil 16.

The switching unit 24 can adjust the transmission and reception directions of the RF signal and the magnetic resonance image signal. For example, during a transmission operation, an RF signal is irradiated to the object through the RF coil 16, and during a reception operation, a magnetic resonance image signal is received from the object through the RF coil 16. The switching operation of the switching unit 24 is controlled by a control signal from the RF control unit 46.

The interface unit 30 can command pulse sequence information to the control unit 40 according to the user's operation and simultaneously transmit commands to control the operation of the entire MRI system. The interface unit 30 may include an image processing unit 36, an output unit 34, and an input unit 32 that process the magnetic resonance image signal received from the RF receiver 38.

The image processor 36 may process the magnetic resonance image signal received from the RF receiver 28 to generate MR image data for the object.

The image processing unit 36 applies various signal processes such as amplification, frequency conversion, phase detection, low-frequency amplification, and filtering to the magnetic resonance image signal received by the RF receiver 28.

For example, the image processing unit 36 may place digital data in k-space and reconstruct the data into image data by performing a 2-dimensional or 3-dimensional Fourier transform.

Additionally, various signal processing applied by the image processor 36 to the magnetic resonance image signal may be performed in parallel. For example, signal processing may be applied in parallel to a plurality of magnetic resonance image signals received by a multi-channel RF coil to reconstruct the plurality of magnetic resonance image signals into image data.

Additionally, the image processing unit 36 generates a blood vessel wall-enhanced image from the magnetic resonance image signal acquired according to the pre-applied pulse train, the specific details of which will be described later.

The output unit 34 may output image data or reconstructed image data generated by the image processing unit 36 to the user. Additionally, the output unit 34 may output information necessary for the user to operate the MRI system, such as a user interface (UI), user information, or object information. The output unit 34 may include a speaker, printer, or various image display means.

The user can input object information, parameter information, scan conditions, pulse sequence, information on image synthesis or difference calculation, etc. through the input unit 32. The input unit 32 may include a keyboard, mouse, trackball, voice recognition unit, gesture recognition unit, touch screen, etc., and may include various other input devices within the range apparent to those skilled in the art.

The control unit 40 includes a sequence control unit 42 that controls the sequence of signals formed inside the MRI scanner 10, and a scanner control unit 48 that controls the MRI scanner 10 and devices mounted on the MRI scanner 10. may include.

The sequence control unit 42 includes a gradient magnetic field control unit 44 that controls the gradient magnetic field amplifier 22, and an RF control unit 46 that controls the RF transmitter 26, the RF receiver 28, and the switching unit 24. do. The sequence control unit 42 may control the gradient magnetic field amplifier 22, the RF transmitter 26, the RF receiver 28, and the switching unit 24 according to the pulse sequence received from the interface unit 30. The pulse sequence includes all information necessary to control the gradient magnetic field amplifier 22, the RF transmitter 26, the RF receiver 28, and the switching unit 24, for example, the pulse applied to the gradient coil 14. It may include information about the strength of the (pulse) signal, application time, application timing, etc.

The control unit 40 provides a pre-applied pulse string to the MRI scanner 10 whose excitation angle is adjusted according to the speed of the tissue of the object. At this time, the pre-applied pulse train is characterized by including a B1 magnetic field and a gradient magnetic field designed so that the lower the tissue velocity, the smaller the applied angle, and the higher the tissue velocity, the larger the applied angle. The specific details will be explained later.

The monitoring unit 50 monitors or controls the MRI scanner 10 or devices mounted on the MRI scanner 10. The monitoring unit 50 may include a system monitoring unit 52, an object monitoring unit 54, a table control unit 56, and a display control unit 58.

The system monitoring unit 52 monitors the state of the static magnetic field, the state of the gradient magnetic field, the state of the RF signal, the state of the RF coil, the state of the table, the state of the device that measures the body information of the object, the state of power supply, the state of the heat exchanger, The status of the compressor can be monitored and controlled.

The object monitoring unit 54 monitors the state of the object, and includes a camera for photographing the movement or position of the object, a respirometer for measuring the breathing of the object, an ECG meter for measuring the electrocardiogram of the object, or a measurement for the body temperature of the object. It may include a temperature measuring device.

The table control unit 56 controls movement of the table on which the object is located. The table control unit 56 can control the movement of the table in synchronization with the sequence control signal output by the sequence control unit 42. For example, in moving imaging of an object, the table control unit 56 can move the table according to sequence control, thereby allowing the object to be moved to a field of view (FOV) larger than the field of view (FOV) of the MRI scanner. can be filmed.

The display control unit 58 turns on/off a display located outside and inside the MRI scanner 10 or controls a screen to be output on the display. Additionally, when a speaker is located inside or outside the MRI scanner 10, the display control unit 58 may control the on/off of the speaker or the sound to be output through the speaker.

The MRI scanner 10, RF coil 16, signal processing unit 20, monitoring unit 50, control unit 40, and interface unit 30 may be connected to each other wirelessly or wired, and when connected wirelessly, they may be connected to each other. A device (not shown) for synchronizing clocks between devices may be further included.

The magnetic resonance image generating device 1 according to an embodiment of the present invention is characterized by the configuration of a control unit 40 and an image processing unit 36. At this time, the image processing unit 36 may perform a magnetic resonance image restoration operation, which will be described later, using the memory and processor mounted on the computing device. That is, a program for restoring a magnetic resonance image from an MRI signal obtained from an object is stored in the memory. Memory is a general term for non-volatile storage devices that retain stored information even when power is not supplied, and volatile storage devices that require power to maintain stored information.

Figure 2 is a diagram illustrating an image in which the blood vessel wall is emphasized, which the present invention seeks to obtain.

As shown on the left side of Figure 2, medical imaging methods for diagnosing vascular diseases have mainly relied on lumen imaging, but this has the limitation of not being able to directly observe the fundamental pathological process that begins in the blood vessel wall. To solve this problem, in the present invention, as shown on the right, the blood flow portion is processed as black blood, which is displayed in black, and the blood vessel wall signal is maximized to provide an image with very high image contrast between the blood vessel wall and the lumen. do.

FIG. 3 is a flowchart showing a method for generating a magnetic resonance image for obtaining an image of a blood vessel wall according to an embodiment of the present invention, and FIG. 4 is a timing diagram showing a method for generating a magnetic resonance image according to an embodiment of the present invention.

First, the control unit 40 of the magnetic resonance image generating device 1 provides a pre-applied pulse train whose excitation angle or bending angle is adjusted according to the speed of the tissue of the object to the MRI scanner 10 (S310). .

At this time, the pre-applied pulse train includes a B1 magnetic field and a gradient magnetic field designed so that the lower the tissue velocity, the smaller the applied angle, and the higher the tissue velocity, the larger the applied angle. As a result, the vertical component of the magnetic spin of the tissue with low velocity is formed to be high, and the vertical component of the magnetic spin of the tissue with high velocity is formed to be low.

Next, a blood vessel wall-emphasized image with image contrast generated from the pre-applied pulse train is generated through a 3D image signal acquisition process (S320).

As shown in FIG. 4, providing a speed-selected pre-applied pulse train (S310), elapse of a predetermined delay time (T1), providing a fat saturation suppression pulse, and segmented 3D magnetic resonance imaging signals. The step S320 of obtaining is performed repeatedly, and a blood vessel wall-emphasized image is generated based on this.

Now, let's look at the main feature of the present invention, the pre-applied pulse train whose application angle is adjusted according to the speed of the tissue, in more detail.

First, in MRI, the process of rotating the magnetic spin of human tissue, which is initially oriented vertically (i.e., in the z direction), around the horizontal axis is called excitation, and the horizontal component of the magnetic spin generated after excitation (usually M _xy The equation expressed as a function of spatial position r and velocity v is as shown in Equation 1 below.

[Equation 1]

It is expressed as the Fourier transform of the B1 magnetic field applied on the multidimensional k-space consisting of _{k r} (Fourier variable of r) and k _v (Fourier variable of v), and the weight of the B1 magnetic field on this k-space is our target. Design the B1 magnetic field and gradient field to be the inverse Fourier transform of the M _xy profile.

k _r is proportional to the area (zero moment) of the gradient magnetic field (G), and k _v is proportional to the first moment (first moment) of the gradient magnetic field.

When used for pre-approval pulse purposes, the M _z component generated as a result of application is important, and the relationship with the M _xy component is expressed in Equation 2 as follows.

[Equation 2]

In other words, as M _z increases, M _xy decreases, and as M _z decreases, M _xy increases.

In the present invention, to design a pre-applied pulse train, the Fourier transform relationship between x(t) and X(w) is designed by applying it to the v and k _v domains of Equation 1.

Figure 5 is a diagram for explaining the Fourier transform equation to be used in the design of the speed selection pre-applied pulse according to an embodiment of the present invention.

As shown in FIG. 5, when x(t) made of a square wave is Fourier transformed, a Fourier transform equation with (-1/n) as a coefficient is derived. At this time, n represents an odd integer.

In this way, the B1 magnetic field and the gradient magnetic field waveform are designed so that a relative weight of size (1/n) is applied to the kv axis, an example of which is shown in FIG. 7.

Figure 6 shows an example of a speed selection pre-applied pulse according to an embodiment of the present invention.

As shown, the gradient magnetic field is provided as a bipolar gradient magnetic field pulse, and the B1 magnetic field is provided as a pulse with an amplitude of (-1/n, n is an odd integer) applied between the pulses of the bipolar gradient magnetic field.

Meanwhile, FIG. 7 expresses the meaning of the pre-applied pulse string shown in FIG. 6 in terms of k-space expressed in Equation 1.

Figure 7 is a diagram illustrating the weight accumulated in k-space by a speed selection pre-applied pulse applied according to an embodiment of the present invention.

Since each bipolar gradient magnetic field pulse has an area of 0, only kv changes in the form of (-1/n) without changing kr, so there is no applied change in the r direction and only in the v direction, x(t in Figure 6 ) occurs in the form of a square wave expressed as . In other words, the application is selective only in velocity but not spatially selective, and thus it is possible to selectively apply the application to the blood vessel wall whose velocity is 0, which is the target of the present invention.

Figure 8 is a diagram showing Mxy and Mz values generated by a speed selection pre-applied pulse according to an embodiment of the present invention.

As shown, the absolute value of Mxy has the same characteristics as the absolute value of x(t) in FIG. 5, and Mz is the minimum when |Mxy| is the maximum by the equation shown in FIG. And when |Mxy| is minimum, Mz becomes maximum and has a relationship. Accordingly, a high signal is obtained for tissues with a moving speed of 0, such as blood vessel walls, and a signal close to 0 is obtained for tissues with a high moving speed, such as blood flow.

To put it another way, in the pre-applied pulse train of the present invention, when the tissue speed is low, the application angle is small, increasing the size (Mz) of the longitudinal component, and when the tissue speed is high, the application angle is increased, so that the longitudinal component is increased. Reduce the size (Mz).

Meanwhile, while applying such a pre-applied pulse train, taking into account the error in the magnetic field within the MRI scanner, a modified pre-applied pulse train can be considered.

Figure 9 shows an example of a speed selection pre-applied pulse according to another embodiment of the present invention.

As shown, it is characterized by the addition of a refocusing pulse for 180 degree rotation in the B1 magnetic field.

The gradient magnetic field is provided in the form of repeated unipolar gradient magnetic field pulses and bipolar gradient magnetic field pulses, and the B1 magnetic field is provided in the form of a refocusing pulse provided between the unipolar gradient magnetic field pulse and the bipolar gradient magnetic field pulse and every two refocusing pulses ( -1/n) are provided as scaled pulses.

Figure 10 shows a blood vessel wall image obtained using a velocity-selective pre-applied pulse train according to an embodiment of the present invention.

The blood vessel walls of the femoral artery and femoral vein within the thigh are clearly visible, and it can be confirmed that the blood flow signal inside the blood vessel wall is well suppressed.

Meanwhile, the method for generating a magnetic resonance image according to an embodiment of the present invention may also be implemented in the form of a recording medium containing instructions executable by a computer, such as a program module executed by a computer. Computer-readable media can be any available media that can be accessed by a computer and includes both volatile and non-volatile media, removable and non-removable media. Additionally, computer-readable media may include all computer storage media. Computer storage media includes both volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules or other data.

The description of the present invention described above is for illustrative purposes, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. will be. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. For example, each component described as unitary may be implemented in a distributed manner, and similarly, components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention. do.

1: Magnetic resonance image generating device
10: MRI scanner
20: signal processing unit
30: Interface part
36: Image processing unit
40: control unit
50: monitoring unit

Claims (11)

In the magnetic resonance image generating device,
A control unit that provides a pre-applied pulse train whose excitation angle is adjusted according to the speed of the object's tissue for the MRI scanner, and
An image processing unit that generates a blood vessel wall-emphasized image from the magnetic resonance image signal collected after application of the pre-applied pulse train,
The control unit provides a pre-applied pulse train including a B1 magnetic field and a gradient magnetic field designed to adjust the application angle in proportion to the speed of the tissue. According to claim 1,
The control unit provides a pre-applied pulse train including a B1 magnetic field and a gradient magnetic field designed to adjust the size of the longitudinal component of the magnetic spin in inverse proportion to the speed of the tissue. delete According to claim 1,
The gradient magnetic field consists of a plurality of bipolar pulses,
The B1 magnetic field is provided as pulses with a magnitude of (-1/n) applied between the bipolar gradient magnetic field pulses. According to claim 1,
The gradient magnetic field is provided in the form of repeated unipolar gradient magnetic field pulses and bipolar gradient magnetic field pulses,
The B1 magnetic field is provided as a refocusing pulse provided between the unipolar gradient magnetic field pulse and the bipolar gradient magnetic field pulse and a pulse with a magnitude of (-1/n) applied every two refocusing pulses, a magnetic resonance image. Generating device. In a magnetic resonance image generating method performed by a magnetic resonance image generating device,
Providing a pre-applied pulse string to the MRI scanner whose excitation angle is adjusted according to the speed of the object's tissue; and
Generating a blood vessel wall-emphasized image from magnetic resonance image signals collected after application of the pre-applied pulse train,
The method of generating a magnetic resonance image, wherein the pre-applied pulse train includes a B1 magnetic field and a gradient magnetic field designed to adjust the application angle in proportion to the speed of the tissue. According to claim 6,
The pre-applied pulse train includes a pre-applied pulse train including a B1 magnetic field and a gradient magnetic field designed to adjust the size of the longitudinal component of the magnetic spin in inverse proportion to the speed of the tissue. delete According to claim 6,
The gradient magnetic field consists of a plurality of bipolar gradient magnetic field pulses,
The B1 magnetic field is provided as a pulse with a magnitude of (-1/n) applied between pulses of the bipolar gradient magnetic field. According to claim 6,
The gradient magnetic field is provided in the form of repeated unipolar gradient magnetic field pulses and bipolar gradient magnetic field pulses,
The B1 magnetic field is provided as a refocusing pulse provided between the unipolar gradient magnetic field pulse and the bipolar gradient magnetic field pulse and a pulse with a magnitude of (-1/n) applied every two refocusing pulses, a magnetic resonance image. How to create it. A computer-readable recording medium recording a computer program for performing the method of any one of claims 6, 7, 9, and 10.

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