KR20160140525A - Magnetic resonance imaging apparatus and imaging method for magnetic resonance image thereof - Google Patents

Abstract

The present invention provides a magnetic resonance imaging device and a method by using magnetic resonance signal, which is received from each of multiple channels coils included in a high frequency multi coil by non-uniformly sampling intervals between two adjacent obtained signals in a first axis direction on a three-dimensional K space.

Description

MAGNETIC RESONANCE IMAGING APPARATUS AND IMAGING METHOD FOR MAGNETIC RESONANCE IMAGE THEREOF FIELD OF THE INVENTION [0001]

Embodiments The present invention relates to a magnetic resonance imaging apparatus and a magnetic resonance imaging method.

More particularly, the disclosed embodiments relate to a magnetic resonance imaging apparatus for acquiring a three-dimensional magnetic resonance image through undersampling on a three-dimensional K-space, and a method of imaging the magnetic resonance imaging.

A magnetic resonance imaging (MRI) imaging device is a device that photographs a subject using a magnetic field. It is widely used for diagnosing accurate diseases because it displays the bone, disk, joints, and nerve ligament in three dimensions at a desired angle have.

A magnetic resonance imaging apparatus acquires a magnetic resonance (MR) signal, reconstructs the acquired magnetic resonance signal into an image, and outputs the reconstructed image. Specifically, a magnetic resonance imaging apparatus acquires a magnetic resonance signal using a high-frequency multi-coil including RF coils, a permanent magnet, and a gradient coil.

More specifically, a high-frequency signal generated by applying a pulse sequence for generating a radio frequency signal to a high-frequency multi-coil is applied to a target object, and a magnetic resonance signal (MR signal) generated corresponding to the applied high- And reconstructs the magnetic resonance image by sampling.

Currently, magnetic resonance imaging (MRI) takes about 1 hour. Generally, a magnetic resonance imaging (MRI) imaging apparatus is formed by a long and narrow barrel (hereinafter referred to as an 'MRI imaging tube'). Therefore, the patient who wants to take a magnetic resonance image should go into the MRI tube and not move during the shooting time. Therefore, it is difficult to take magnetic resonance imaging in patients with ICU or claustrophobia, and even in the case of general patients, as the time taken for imaging becomes longer, the user feels boredom and inconvenience.

Therefore, there is a need for an image processing apparatus and method that can shorten the imaging time of the magnetic resonance imaging.

In order to shorten the imaging time of the MR image, the MR signal is acquired at some points of the K-space image without performing a full sampling of sampling the MR signal at all points of the K-space image, It is possible to use a method of undersampling that is not obtained in the above-described case. Here, unacquired signals in the incomplete K spatial data obtained through undersampling can be restored through calibration.

As an image processing method for restoring a magnetic resonance image, a generalized autocalibrating partially parallel acquisitions (GRAPPA) technique can be exemplified.

Specifically, the generalized autocalibrating partially parallel acquisitions (GRAPPA) technique is a K-space based imaging method. The spatial correlation coefficient, which is the spatial interaction value between the calibration signal and the adjacent measured source signal through self calibration, And estimates an unacquired signal using the calculated spatial correlation coefficient. Here, the spatial correlation coefficient may be referred to as a convolution kernels.

Specifically, the Grafu technique uses the measured line data, which is undersampled data, and the additionally obtained ACS line (ACOC line) data, to restore the lines of the K space that are not obtained .

In the case of restoring the K-space data by performing the calibration, when the data of the video signal is damaged by the noise or the spatial interaction value is changed, aliasing artifacts of the finally obtained magnetic resonance image and the amplified noise There is a problem in that a problem occurs.

Therefore, there is a need to provide an imaging method and apparatus capable of rapidly recovering a magnetic resonance image while reducing the amount of aliasing defects and suppressing amplified noise, thereby having an improved image quality.

It is an object of the disclosed embodiments to provide a magnetic resonance imaging apparatus and a magnetic resonance imaging imaging method capable of improving the image quality of a reconstructed 3D MRI image.

It is another object of the disclosed embodiments to provide a magnetic resonance imaging apparatus capable of shortening the imaging time of a magnetic resonance imaging and a method of imaging the magnetic resonance imaging.

It is another object of the disclosed embodiments to provide a magnetic resonance imaging apparatus capable of reducing the reconstruction time of a magnetic resonance image and a method of imaging the magnetic resonance imaging.

Further, it is also possible to use an additional calibration signal obtained in a part of the K space such as the disclosed Grafu technique, or to use the Coil Sensitivity Maps with additional coil information, such as the SMASH technique, A magnetic resonance imaging apparatus capable of reconstructing a 3D magnetic resonance image quickly and accurately using only acquired signals included therein, and a method of imaging a magnetic resonance image.

The magnetic resonance imaging apparatus according to the disclosed embodiment converts a magnetic resonance signal received at each of a plurality of channel coils included in a high frequency multi-coil into a signal having a gap between two acquired signals in a first axis direction on a three- A data acquiring unit for acquiring a plurality of incomplete three-dimensional K-space data corresponding to each of the plurality of channel coils by sampling so as to be nonuniform; And an image processor for reconstructing the complete three-dimensional K-space data based on the spatial relationship between the acquired signals contained in the incomplete three-dimensional K-space data.

The data obtaining unit may sample the magnetic resonance signal to obtain the incomplete three-dimensional K-space data so that the interval between two acquired signals in the first axis direction in the entire three-dimensional K space is uneven .

In addition, the data acquiring section includes at least one first plane to be fully sampled, at least one second plane to be regularly undersampled, and at least one third plane to be unsampled, and is perpendicular to the first axis and mutually adjacent , The magnetic resonance signal can be sampled to obtain the incomplete three-dimensional K-space data.

In addition, a non-uniform sampling pattern formed by sampling the magnetic resonance signals line by line, such that intervals between two obtained signals in the first axis direction on the three-dimensional K space become uneven, Can be repeated a plurality of times on the three-dimensional K space corresponding to each of them.

The data acquiring section may further include a line that is parallel to a second axis direction perpendicular to the first axis and is completely sampled so as to make the interval between two acquired signals in the first axis direction on the three- Data can be obtained, and the incomplete three-dimensional K-space data can be obtained. Also, at least one line formed in the direction parallel to the first axis in the incomplete three-dimensional K-space data may form a non-uniform sampling pattern in which the interval between two adjacent acquired signals is nonuniform.

The plurality of obtained line data parallel to the second axis direction perpendicular to the first axis direction in the incomplete three-dimensional K space data may be obtained by adding the acquired two line data of the plurality of acquired line data It is possible to form a non-uniform sampling pattern in which the intervals between the sampling points are nonuniform.

The image processing unit may acquire a first spatial correlation coefficient based on a spatial relationship between a reference signal, which is one signal obtained, and a plurality of other signals obtained in the incomplete three-dimensional K spatial data, Based on the first spatial correlation coefficient, at least one undetected signal in the incomplete three-dimensional K spatial data.

In addition, if the first signal, which is an unacquired signal included in the incomplete three-dimensional K spatial data, and the acquired plurality of signals satisfy the spatial relationship, the image processor may further include: Signal can be obtained.

The image processing unit may divide the incomplete three-dimensional K-space data into a plurality of blocks, and restore the complete three-dimensional K-space data on a block-by-block basis based on the relationship between the acquired signals contained in the divided K- can do.

The non-uniform sampling pattern formed by the plurality of line data parallel to the second axial direction perpendicular to the first axis direction in the incomplete three-dimensional K spatial data may be the same in each of the plurality of blocks.

In addition, the data obtaining unit may obtain at least one signal in any one of the plurality of blocks.

In addition, the data acquisition unit may acquire at least one signal in any one of the plurality of blocks.

In addition, the non-uniform sampling pattern formed by the line parallel to the first axis direction in the incomplete three-dimensional K-space data may be different in at least two of the plurality of blocks.

The controller may further include a controller for setting a non-uniform sampling pattern corresponding to a block located at the center of the three-dimensional K space to be denser than a non-uniform sampling pattern corresponding to a block located in the periphery of the three- have.

Also, the image processor may recover the complete three-dimensional K-space data corresponding to the plurality of channel coils by restoring the complete three-dimensional K-space data for each of the plurality of channel coils.

In addition, the image processing unit may perform spatial transform of the plurality of complete three-dimensional K spatial data, sum up the plurality of completely three-dimensional K spatial data, and restore the 3D magnetic resonance image .

A magnetic resonance imaging apparatus according to the disclosed embodiment includes a plurality of channel coils receiving a magnetic resonance signal, which is a high frequency emitted from a nuclear spin of the object in response to an applied high frequency, A high frequency multi-coil including; Sampling the magnetic resonance signal so that the interval between two acquired signals in the first axis direction on the three-dimensional K space becomes non-uniform, and acquiring a plurality of incomplete three-dimensional K space data corresponding to each of the plurality of channel coils A signal transmission / reception unit; And an image processor for restoring the complete three-dimensional K-space data based on the relationship between the obtained signals contained in the incomplete three-dimensional K-space data.

The method of imaging a magnetic resonance image according to the disclosed embodiment is a method for imaging a magnetic resonance signal received at each of a plurality of channel coils included in a high frequency multi-coil, between two acquired signals adjacent in a first axis direction on a three- Sampling the incomplete three-dimensional K-space data corresponding to each of the plurality of channel coils to obtain a plurality of incomplete three-dimensional K-space data; And reconstructing the complete three-dimensional K-space data based on the spatial relationship between the acquired signals contained in the incomplete three-dimensional K-space data.

The acquiring step may include sampling the magnetic resonance signal so that an interval between two acquired signals in the first axis direction in the entire three-dimensional K space is uneven, thereby generating a plurality of incomplete three-dimensional K- And a step of acquiring.

In addition, the acquiring step includes at least one first plane to be fully sampled, at least one second plane to be regularly undersampled, and at least one third plane to be unsampled, and is perpendicular to the first axis And sampling the magnetic resonance signal to obtain the incomplete three-dimensional K-space data at the adjacent plurality of planes.

In addition, a non-uniform sampling pattern formed by sampling the magnetic resonance signals line by line, such that intervals between two obtained signals in the first axis direction on the three-dimensional K space become uneven, Can be repeated a plurality of times on the three-dimensional K space corresponding to each of them.

The step of acquiring the plurality of incomplete three-dimensional K-space data may further include a step of acquiring a plurality of incomplete three-dimensional K- Acquiring line data that is parallel to the axial direction and is completely sampled, and obtaining the incomplete three-dimensional K-space data. Also, at least one line formed in the direction parallel to the first axis in the incomplete three-dimensional K-space data may form a non-uniform sampling pattern in which the interval between two adjacent acquired signals is nonuniform.

The reconstructing may include obtaining a first spatial correlation coefficient based on a spatial relationship between a reference signal, which is one signal obtained, and a plurality of other signals obtained, in the incomplete three-dimensional K spatial data; And reconstructing at least one non-acquired signal in the incomplete three-dimensional K spatial data based on the spatial relationship and the first spatial correlation coefficient.

The reconstructing of the at least one unacquired signal may include: if the first signal, which is an unacquired signal included in the incomplete three-dimensional K spatial data, and the acquired plurality of signals satisfy the spatial relationship, And acquiring the first signal based on the spatial correlation coefficient.

The reconstructing step may include: dividing the incomplete three-dimensional K-space data into a plurality of blocks; And reconstructing the complete three-dimensional K spatial data on a block-by-block basis, based on the relationship between the obtained signals contained in the divided K spatial data.

In addition, the non-uniform sampling pattern formed by the line parallel to the first axis direction in the incomplete three-dimensional K-space data may be the same in each of the plurality of blocks.

The non-uniform sampling pattern formed by the plurality of line data parallel to the second axis direction perpendicular to the first axis direction in the incomplete three-dimensional K space data may be different from at least two of the plurality of blocks have.

The acquiring step may further include setting a non-uniform sampling pattern corresponding to a block located at the center of the three-dimensional K space to be more denser than a non-uniform sampling pattern corresponding to a block located in the periphery of the three- As shown in FIG.

The restoring may include restoring the complete three-dimensional K-space data for each of the plurality of channel coils. The method of imaging a magnetic resonance image may further comprise reconstructing a plurality of complete three-dimensional K-space data corresponding to the plurality of channel coils.

In addition, a method of imaging a magnetic resonance image may include spatial transforming the plurality of complete three-dimensional (K) spatial data; And summing the plurality of complete three-dimensional K-space data subjected to the spatial transformation to recover a 3D magnetic resonance image.

1 is a schematic diagram of a general MRI system.
2 is a detailed view of a communication unit included in the MRI system of FIG.
3 is a block diagram showing a magnetic resonance imaging apparatus according to an embodiment.
4A is another diagram showing a magnetic resonance imaging apparatus according to the embodiment.
4B is a view showing a three-dimensional K space.
5 is a diagram for explaining a magnetic resonance image obtained by sampling a magnetic resonance signal on a three-dimensional K space.
6A is another diagram showing a magnetic resonance imaging apparatus according to the embodiment.
FIG. 6B is a view for explaining the operation of the magnetic resonance imaging apparatus shown in FIG. 6A.
FIG. 6C is another drawing for explaining the operation of the magnetic resonance imaging apparatus shown in FIG. 6A.
6D is another diagram for explaining the operation of the MRI apparatus shown in FIG.
7 is a view for explaining a sampling operation of a magnetic resonance image according to the embodiment.
8 is a view for explaining a restoration operation of three-dimensional K-space data according to the embodiment.
FIG. 9A is a diagram for explaining acquisition of a spatial correlation coefficient. FIG.
9B is a diagram for explaining the setting of a sampling pattern for each block.
Figs. 9C to 9F are diagrams for explaining embodiments for setting a non-uniform sampling pattern. Fig.
10 is a diagram for explaining the weighting matrix W in detail.
11 is a diagram for explaining a restoration operation of a magnetic resonance image according to the embodiment.
12 is a view showing reconstructed magnetic resonance images according to an embodiment.
13 is a flowchart showing a method of imaging a magnetic resonance image according to the embodiment.

Brief Description of the Drawings The advantages and features of the present invention, and how to accomplish them, will become apparent with reference to the embodiments described hereinafter with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

The terms used in this specification will be briefly described and the present invention will be described in detail.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. Also, in certain cases, there may be a term selected arbitrarily by the applicant, in which case the meaning thereof will be described in detail in the description of the corresponding invention. Therefore, the term used in the present invention should be defined based on the meaning of the term, not on the name of a simple term, but on the entire contents of the present invention.

When an element is referred to as "including" an element throughout the specification, it is to be understood that the element may include other elements as well, without departing from the spirit or scope of the present invention. Also, as used herein, the term "part " refers to a hardware component such as software, FPGA or ASIC, and" part " However, "part" is not meant to be limited to software or hardware. "Part" may be configured to reside on an addressable storage medium and may be configured to play back one or more processors. Thus, by way of example, and not limitation, "part (s) " refers to components such as software components, object oriented software components, class components and task components, and processes, Subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays and variables. The functions provided in the components and "parts " may be combined into a smaller number of components and" parts " or further separated into additional components and "parts ".

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. In order to clearly explain the present invention in the drawings, parts not related to the description will be omitted.

As used herein, an "image" may refer to multi-dimensional data composed of discrete image elements (e.g., pixels in a two-dimensional image and voxels in a three-dimensional image). For example, the image may include an X-ray device, a CT device, an MRI device, an ultrasound diagnostic device, and a medical image of an object acquired by another medical imaging device.

Also, in this specification, an "object" may include a person or an animal, or a part of a person or an animal. For example, the subject may include a liver, a heart, a uterus, a brain, a breast, an organ such as the abdomen, or a blood vessel. The "object" may also include a phantom. A phantom is a material that has a volume that is very close to the density of the organism and the effective atomic number, and can include a spheric phantom that has body-like properties.

In this specification, the term "user" may be a doctor, a nurse, a clinical pathologist, a medical imaging expert or the like as a medical professional and may be a technician repairing a medical device, but is not limited thereto.

In the present specification, the term "MR image (Magnetic Resonance image) " means an image of a target object obtained using the nuclear magnetic resonance principle.

In the present specification, the term "pulse sequence" means a series of signals repeatedly applied in the MRI system. The pulse sequence may include a time parameter of the RF pulse, for example, a Repetition Time (TR) and a Time to Echo (TE).

In addition, the term " pulse sequence diagram "in this specification describes the order of events occurring in the MRI system. For example, the pulse sequence schematic diagram may be a schematic diagram showing an RF pulse, a gradient magnetic field, an MR signal, and the like over time.

The MRI system is a device for acquiring an image of a single-layer region of a target object by expressing intensity of an MR (Magnetic Resonance) signal for a RF (Radio Frequency) signal generated in a magnetic field of a specific intensity in contrast. For example, an MR signal is emitted from the specific nucleus when an object is instantaneously examined and discontinued after an RF signal that lies in a strong magnetic field and resonates only with a specific nucleus (e.g., a hydrogen nucleus) And the MR image can be acquired by receiving the MR signal. The MR signal means an RF signal radiated from the object. The magnitude of the MR signal can be determined by the concentration of a predetermined atom (e.g., hydrogen) included in the object, the relaxation time T1, the relaxation time T2, and the flow of blood.

The MRI system includes features different from other imaging devices. Unlike imaging devices, such as CT, where acquisitions of images are dependent on the direction of the detecting hardware, the MRI system can acquire oriented 2D images or 3D volume images at any point. Further, unlike CT, X-ray, PET, and SPECT, the MRI system does not expose radiation to the subject and the examiner, and it is possible to acquire images having a high soft tissue contrast, The neurological image, the intravascular image, the musculoskeletal image and the oncologic image can be acquired.

1 is a schematic diagram of a general MRI system. Referring to FIG. 1, the MRI system may include a gantry 20, a signal transceiver 30, a monitoring unit 40, a system controller 50, and an operating unit 60.

The gantry 20 blocks electromagnetic waves generated by the main magnet 22, the gradient coil 24, the RF coil 26 and the like from being radiated to the outside. A static magnetic field and an oblique magnetic field are formed in the bore in the gantry 20, and an RF signal is radiated toward the object 10.

The main magnet 22, the gradient coil 24, and the RF coil 26 may be disposed along a predetermined direction of the gantry 20. The predetermined direction may include a coaxial cylindrical direction or the like. The object 10 can be placed on a table 28 insertable into the cylinder along the horizontal axis of the cylinder.

The main magnet 22 generates a static magnetic field or a static magnetic field for aligning the magnetic dipole moment of the nuclei included in the object 10 in a predetermined direction. As the magnetic field generated by the main magnet is strong and uniform, a relatively precise and accurate MR image of the object 10 can be obtained.

The gradient coil 24 includes X, Y, and Z coils that generate a gradient magnetic field in the X-axis, Y-axis, and Z-axis directions orthogonal to each other. The gradient coil 24 can provide position information of each part of the object 10 by inducing resonance frequencies differently for each part of the object 10.

The RF coil 26 can irradiate the RF signal to the patient and receive the MR signal emitted from the patient. Specifically, the RF coil 26 transmits an RF signal having the same frequency as the frequency of the car motions to the atomic nuclei present in the patient who carries out the car wash motion, stops the transmission of the RF signal, Lt; RTI ID = 0.0 > MR < / RTI >

For example, the RF coil 26 generates an electromagnetic wave signal having a radio frequency corresponding to the kind of the atomic nucleus, for example, an RF signal, to convert a certain atomic nucleus from a low energy state to a high energy state, 10). When an electromagnetic wave signal generated by the RF coil 26 is applied to an atomic nucleus, the atomic nucleus can be transited from a low energy state to a high energy state. Thereafter, when the electromagnetic wave generated by the RF coil 26 disappears, the atomic nucleus to which the electromagnetic wave has been applied can emit electromagnetic waves having a Lamor frequency while transiting from a high energy state to a low energy state. In other words, when the application of the electromagnetic wave signal to the atomic nucleus is interrupted, the energy level from the high energy to the low energy is generated in the atomic nucleus where the electromagnetic wave is applied, and the electromagnetic wave having the Lamor frequency can be emitted. The RF coil 26 can receive an electromagnetic wave signal radiated from the nuclei inside the object 10.

The RF coil 26 may be implemented as a single RF transmitting / receiving coil having both a function of generating an electromagnetic wave having a radio frequency corresponding to the type of the atomic nucleus and a function of receiving electromagnetic waves radiated from the atomic nucleus. It may also be implemented as a receiving RF coil having a function of generating an electromagnetic wave having a radio frequency corresponding to the type of an atomic nucleus and a receiving RF coil having a function of receiving electromagnetic waves radiated from the atomic nucleus.

In addition, the RF coil 26 may be fixed to the gantry 20 and may be removable. The removable RF coil 26 may include an RF coil for a portion of the object including a head RF coil, a thorax RF coil, a bridge RF coil, a neck RF coil, a shoulder RF coil, a wrist RF coil, and an ankle RF coil. have.

Also, the RF coil 26 can communicate with an external device by wire and / or wireless, and can perform dual tune communication according to a communication frequency band.

The RF coil 26 may include a birdcage coil, a surface coil, and a transverse electromagnetic coil (TEM coil) according to the structure of the coil.

In addition, the RF coil 26 may include a transmission-only coil, a reception-only coil, and a transmission / reception-use coil according to an RF signal transmitting / receiving method.

In addition, the RF coil 26 may include RF coils of various channels such as 16 channels, 32 channels, 72 channels, and 144 channels.

The gantry 20 may further include a display 29 located outside the gantry 20 and a display (not shown) located inside the gantry 20. It is possible to provide predetermined information to a user or an object through a display located inside and outside the gantry 20.

The signal transmitting and receiving unit 30 controls the inclined magnetic field formed in the gantry 20, that is, the bore, according to a predetermined MR sequence, and can control transmission and reception of the RF signal and the MR signal.

The signal transmitting and receiving unit 30 may include a gradient magnetic field amplifier 32, a transmitting and receiving switch 34, an RF transmitting unit 36, and an RF receiving unit 38.

The gradient magnetic field amplifier 32 drives the gradient coil 24 included in the gantry 20 and generates a pulse signal for generating a gradient magnetic field under the control of the gradient magnetic field control unit 54, . By controlling the pulse signals supplied from the oblique magnetic field amplifier 32 to the gradient coil 24, gradient magnetic fields in the X-axis, Y-axis, and Z-axis directions can be synthesized.

The RF transmitter 36 and the RF receiver 38 can drive the RF coil 26. The RF transmitting unit 36 supplies RF pulses of the Ramore frequency to the RF coil 26 and the RF receiving unit 38 can receive the MR signals received by the RF coil 26.

The transmission / reception switch 34 can adjust the transmission / reception direction of the RF signal and the MR signal. For example, an RF signal may be irradiated to the object 10 through the RF coil 26 during a transmission mode, and an MR signal from the object 10 may be received via the RF coil 26 during a reception mode . The transmission / reception switch 34 can be controlled by a control signal from the RF control unit 56. [

The monitoring unit 40 can monitor or control devices mounted on the gantry 20 or the gantry 20. The monitoring unit 40 may include a system monitoring unit 42, an object monitoring unit 44, a table control unit 46, and a display control unit 48.

The system monitoring unit 42 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 for measuring the body information of the object, You can monitor and control the state of the compressor.

The object monitoring unit 44 monitors the state of the object 10. Specifically, the object monitoring unit 44 includes a camera for observing the movement or position of the object 10, a respiration measuring unit for measuring respiration of the object 10, an ECG measuring unit for measuring the electrocardiogram of the object 10, Or a body temperature measuring device for measuring the body temperature of the object 10. [

The table control unit 46 controls the movement of the table 28 on which the object 10 is located. The table control unit 46 may control the movement of the table 28 in accordance with the sequence control of the sequence control unit 52. [ For example, in moving imaging of a subject, the table control unit 46 may move the table 28 continuously or intermittently according to the sequence control by the sequence control unit 52, , The object can be photographed with a FOV larger than the field of view (FOV) of the gantry.

The display control unit 48 controls the displays located outside and inside the gantry 20. Specifically, the display control unit 48 can control on / off of a display located outside and inside of the gantry 20, a screen to be output to the display, and the like. Further, when a speaker is located inside or outside the gantry 20, the display control unit 48 may control on / off of the speaker, sound to be output through the speaker, and the like.

The system control unit 50 includes a sequence control unit 52 for controlling a sequence of signals formed in the gantry 20 and a gantry control unit 58 for controlling gantry 20 and devices mounted on the gantry 20 can do.

The sequence control section 52 includes an inclination magnetic field control section 54 for controlling the gradient magnetic field amplifier 32 and an RF control section 56 for controlling the RF transmission section 36, the RF reception section 38 and the transmission / reception switch 34 can do. The sequence control unit 52 can control the gradient magnetic field amplifier 32, the RF transmission unit 36, the RF reception unit 38 and the transmission / reception switch 34 in accordance with the pulse sequence received from the operating unit 60. [ Here, the pulse sequence includes all information necessary for controlling the oblique magnetic field amplifier 32, the RF transmitter 36, the RF receiver 38, and the transmitter / receiver switch 34. For example, Information on the intensity of the pulse signal applied to the coil 24, the application time, the application timing, and the like.

The operating unit 60 can instruct the system control unit 50 of the pulse sequence information and can control the operation of the entire MRI system.

The operating unit 60 may include an image processing unit 62, an output unit 64, and an input unit 66 that receive and process the MR signal received by the RF receiving unit 38.

The image processing unit 62 can process the MR signal received from the RF receiving unit 38 to generate MR image data for the object 10.

The image processing unit 62 receives the MR signal received by the RF receiving unit 38 and applies various signal processing such as amplification, frequency conversion, phase detection, low frequency amplification, filtering, and the like to the received MR signal.

The image processing unit 62 arranges digital data in a k space (for example, a Fourier space or a frequency space) of a memory and performs two-dimensional or three-dimensional Fourier transform on the data, Data can be reconstructed.

If necessary, the image processing unit 62 performs synthesis processing or difference calculation processing (K3 answer-latter processing) on the reconstructed image data (data), and performs synthesis processing or difference processing processing on the reconstructed image data ) Can be performed. The compositing process may be an addition process, a maximum value projection (MIP) process, etc. for the pixel (K4 answer: followed by an addition process and a maximum value process). Further, the image processing unit 62 can store not only the image data to be reconstructed but also the image data on which the combining process and the difference calculating process have been performed in a memory (not shown) or an external server.

In addition, various signal processes applied to the MR signal by the image processing unit 62 may be performed in parallel. For example, a plurality of MR signals may be reconstructed into image data by applying signal processing to a plurality of MR signals received by the multi-channel RF coil in parallel.

The output unit 64 can output the image data or the reconstructed image data generated by the image processing unit 62 to the user. The output unit 64 may output information necessary for a user to operate the MRI system, such as a UI (user interface), user information, or object information. The output unit 64 may be a speaker, a printer, a CRT display, an LCD display, a PDP display, an OLED display, an FED display, an LED display, a VFD display, a DLP (Digital Light Processing) display, a flat panel display (PFD) Display, transparent display, and the like, and may include various output devices within a range that is obvious to those skilled in the art.

The user can input object information, parameter information, scan conditions, pulse sequence, information on image synthesis and calculation of difference, etc., by using the input unit 66. [ Examples of the input unit 66 may include a keyboard, a mouse, a trackball, a voice recognition unit, a gesture recognition unit, a touch screen, and the like, and may include various input devices within a range obvious to those skilled in the art.

1, the signal transmission / reception unit 30, the monitoring unit 40, the system control unit 50, and the operating unit 60 are shown as separate objects. However, the signal transmission / reception unit 30, the monitoring unit 40, Those skilled in the art will appreciate that the functions performed by the control unit 50 and the operating unit 60, respectively, may be performed in different objects. For example, the image processor 62 described above converts the MR signal received by the RF receiver 38 into a digital signal, but the RF receiver 38 or the RF coil 26 directly converts the MR signal received by the RF receiver 38 into a digital signal. .

The gantry 20, the RF coil 26, the signal transmitting and receiving unit 30, the monitoring unit 40, the system control unit 50 and the operating unit 60 may be connected to each other wirelessly or wired, And a device (not shown) for synchronizing clocks with each other. Communication between the gantry 20, the RF coil 26, the signal transmitting and receiving unit 30, the monitoring unit 40, the system control unit 50 and the operating unit 60 can be performed at a high speed such as LVDS (Low Voltage Differential Signaling) A digital interface, an asynchronous serial communication such as a universal asynchronous receiver transmitter (UART), a hypo-synchronous serial communication, or a CAN (Controller Area Network) can be used. Various communication methods can be used.

2 is a diagram showing a configuration of a communication unit 70 according to an embodiment of the present invention. The communication unit 70 may be connected to at least one of the gantry 20, the signal transmission / reception unit 30, the monitoring unit 40, the system control unit 50, and the operating unit 60 shown in FIG.

The communication unit 70 can exchange data with other medical devices in a hospital server or a hospital connected through a PACS (Picture Archiving and Communication System), and can transmit and receive data in a digital image and communication (DICOM) Medicine) standards.

2, the communication unit 70 may be connected to the network 80 by wired or wireless communication with the server 92, the medical device 94, or the portable device 96. [

Specifically, the communication unit 70 can transmit and receive data related to the diagnosis of the object through the network 80, and can transmit and receive the medical image captured by the medical device 94 such as CT, MRI, X-ray and the like. Further, the communication unit 70 may receive the diagnosis history of the patient, the treatment schedule, and the like from the server 92 and utilize it for diagnosis of the target object. The communication unit 70 may perform data communication with not only the server 92 in the hospital or the medical device 94 but also the portable device 96 such as a doctor, a customer's mobile phone, a PDA, or a notebook computer.

Also, the communication unit 70 may transmit the abnormality of the MRI system or the medical image quality information to the user via the network 80, and may receive the feedback from the user.

The communication unit 70 may include one or more components that enable communication with an external device and may include, for example, a short range communication module 72, a wired communication module 74 and a wireless communication module 76 have.

The short-range communication module 72 refers to a module for performing short-range communication with a device located within a predetermined distance. The local area communication technology according to the embodiment of the present invention may include a wireless LAN, a Wi-Fi, a Bluetooth, a zigbee, a Wi-Fi direct, an ultra wideband (UWB) , Infrared Data Association (BDE), Bluetooth Low Energy (BLE), Near Field Communication (NFC), and the like.

The wired communication module 74 is a module for performing communication using an electric signal or an optical signal. The wired communication module according to the embodiment of the present invention uses a pair cable, a coaxial cable, an optical fiber cable, Wired communication technology may be included, and wired communication technology that is obvious to those skilled in the art may be included.

The wireless communication module 76 transmits and receives a wireless signal to at least one of a base station, an external device, and a server on the mobile communication network. Here, the wireless signal may include various types of data depending on a voice call signal, a video call signal, or a text / multimedia message transmission / reception.

3 is a block diagram showing a magnetic resonance imaging apparatus according to an embodiment.

The magnetic resonance imaging apparatus 300 according to the disclosed embodiment may be any apparatus capable of generating, processing, and / or displaying a magnetic resonance image. Specifically, the magnetic resonance imaging apparatus 300 may be a device for imaging a magnetic resonance image using a magnetic resonance signal obtained from a plurality of channel coils included in a high-frequency multi-coil (not shown).

For example, the magnetic resonance imaging apparatus 300 may be included in the MRI system described with reference to FIGS. 1, the data acquisition unit 310 and the image processing unit 320 of FIG. 1 each include the signal transmission / reception unit 30 and the image processing unit 62 of FIG. 1, respectively, ). ≪ / RTI >

The magnetic resonance imaging apparatus 300 further includes an image processing apparatus for receiving the data obtained by magnetic resonance imaging of the object, for example, a magnetic resonance signal, and reconstructing the magnetic resonance image using the received magnetic resonance signal .

The magnetic resonance imaging apparatus 300 may be a server apparatus that receives a magnetic resonance signal obtained by capturing a magnetic resonance image of a target object, and reconstructs a magnetic resonance image using the received magnetic resonance signal. Here, the server device may be a medical server device in a hospital or other hospital where a patient performs magnetic resonance imaging.

Specifically, the magnetic resonance imaging apparatus 300 may be a server 92, a medical device 94, or a portable device 96 that operates in conjunction with the MRI system described with reference to FIGS. 1 and 2, And a magnetic resonance signal obtained from the system is transmitted to perform a restoration operation of the magnetic resonance image.

Referring to FIG. 3, the MRI apparatus 300 according to the disclosed embodiment includes a data obtaining unit 310 and an image processing unit 320.

The data obtaining unit 310 obtains raw data for reconstructing a magnetic resonance image by taking a magnetic resonance imaging (MRI) image of the object. Here, the RF data is obtained by magnetic resonance imaging (MRI) of a magnetic resonance signal having a form of a radio frequency signal received from each of a plurality of channel coils included in a radio frequency multi-coil (not shown) (MR signal).

Here, a high frequency multi-coil (not shown) corresponds to the RF coil 26 shown in FIG. The data acquisition unit 310 may be connected to the RF data acquisition unit 38 shown in FIG. 1 and may receive a magnetic resonance signal from the RF data acquisition unit 38.

Also, the data obtaining unit 310 may include the RF data obtaining unit 38 shown in FIG. When the data acquisition unit 310 includes the RF data acquisition unit 38, the data acquisition unit 310 may acquire magnetic resonance signals through the RF data acquisition unit 38 itself. 1, the data acquisition unit 310 of the magnetic resonance imaging apparatus 300 includes a signal transmission / reception unit (not shown) including the RF data acquisition unit 38 30).

The data obtaining unit 310 samples the magnetic resonance signal to obtain K-space data. Here, the K space data represents a magnetic resonance signal, which is a radio frequency (RF) signal received from each of the coils of each channel included in the high frequency multi-coil (not shown) It means a signal generated by placing.

Here, the high frequency multi-coil (not shown) includes a plurality of channel coils for transmitting and receiving a high frequency signal. For example, a high frequency multi-coil (not shown) includes n channel coils. And, each of the n channel coils receives the magnetic resonance signal individually. The data obtaining unit 310 may obtain n K spatial data corresponding to each of the n channel coils using the magnetic resonance signal received from each of the n channel coils.

The K spatial data may be two-dimensional K spatial data or three-dimensional K spatial data. For example, the two-dimensional K-space data has a spatial frequency domain in a two-dimensional space, and is formed by a Kx-axis corresponding to a frequency encoding and a ky-axis corresponding to a phase encoding do. Further, the three-dimensional K-space data is formed by the Kx-axis, the Ky-axis, and the Kz-axis corresponding to the traveling direction on the space. Here, the Kz axis corresponds to a slice selection gradient.

Specifically, the data acquiring unit 310 acquires incomplete three-dimensional K-space data by sampling the magnetic resonance signal emitted from the object on the three-dimensional K-space. Specifically, the data obtaining unit 310 obtains incomplete three-dimensional K-space data for each channel, and obtains a plurality of incomplete three-dimensional K-space data corresponding to each of the plurality of channel coils. Here, 'incomplete three-dimensional K-space data' means K-space data in which a magnetic resonance signal is not sampled at at least one point in the K-space, so that the signal at at least one point in the K-space needs to be restored . The 'incomplete three-dimensional K spatial data' is data obtained by sampling a magnetic resonance signal received from a high-frequency multi-coil (not shown), and raw data before performing a restoration operation of an unacquired signal . Specifically, the data acquisition unit 310 may acquire a plurality of incomplete three-dimensional K spatial data corresponding to the plurality of channel coils through under sampling. For example, when undosampling is performed to restore a two-dimensional image having a resolution of 256 * 256, image values (MR signal values) corresponding to some points in an image grid having 256 * . In addition, unacquired signals can be recovered using the obtained signals.

Subsequently, the data obtaining unit 310 may transmit a plurality of incomplete K space data corresponding to each of the plurality of channel coils to the image processing unit 320.

The case where the data acquisition unit 310 samples a magnetic resonance signal to acquire a plurality of incomplete three-dimensional K-space data corresponding to each of the plurality of channel coils is described as an example. However, the data acquiring unit 310 may merely receive the magnetic resonance signals from each of the plurality of channel coils, and the sampling operation may be performed in the image processing unit 320. That is, the image processing unit 320 may acquire incomplete three-dimensional K-space data by sampling the received magnetic resonance signal. Hereinafter, a case where the data acquisition unit 310 performs a sampling operation to acquire incomplete three-dimensional K-space data will be described as an example.

The data acquisition unit 310 converts a magnetic resonance signal received in each of the plurality of channel coils included in the high frequency multi-coil into a signal having a non-uniform spacing between the two acquired signals in the first axis direction on the three- -uniform) so as to acquire a plurality of incomplete three-dimensional K-space data corresponding to each of the plurality of channel coils.

The image processing unit 320 reconstructs the complete three-dimensional K-space data based on the spatial relationship between the acquired signals included in the incomplete three-dimensional K-space data. In detail, the image processing unit 320 may recover complete three-dimensional K-space data for each channel to restore a plurality of complete three-dimensional K-space data corresponding to each of the plurality of channel coils.

The operation of the data acquisition unit 310 and the image processing unit 320 will be described in detail with reference to FIGS. 4A to 11 below.

4A is another diagram showing a magnetic resonance imaging apparatus according to the embodiment.

4A, the data acquisition unit 410 and the image processing unit 420 of the MRI apparatus 400 according to the embodiment are respectively connected to the data acquisition unit 310 and the image processing unit 320 of FIG. 3, The same can be coped with. Therefore, the description of the magnetic resonance imaging apparatus 400 that is the same as that in FIG. 3 will be omitted.

The magnetic resonance imaging apparatus 400 includes a high frequency multi-coil 405, a control unit 425, a display unit 450, a user interface unit 460, and a communication unit 470). ≪ / RTI >

The RF coil 26, the system control unit 50, and the communication unit 470 described in FIGS. 1 and 2 are connected to the high frequency multi-coil 405, the control unit 425, the display unit 450, the user interface unit 460, The output unit 64, the input unit 66, and the communication unit 70, respectively, so that descriptions overlapping with those of FIGS. 1 and 2 will be omitted.

The high frequency multi-coil 405 corresponds to the RF coil 26 shown in Fig. The high frequency multi-coil 405 includes a plurality of channel coils. For example, the high frequency multi-coil 405 includes first through n-th channel coils, and each of the n channel coils receives a magnetic resonance signal that is a high frequency (RF) signal.

Specifically, a plurality of channel coils are included to apply a high frequency RF to a target object of the high frequency multi-coil 405 and receive a high frequency magnetic resonance signal corresponding to the applied high frequency and emitted from a nuclear spin of the target object do.

Specifically, the high-frequency multi-coil 405 applies RF-Radio frequency signals to the object to excite nuclear spins of the object. Then, the nuclear spin of the object is transferred to the high energy state by the applied high frequency signal, and then the energy remaining after returning to the original energy state is released to the outside. At this time, energy emitted from the nuclear spin becomes a magnetic resonance (MR) signal having a form of a high frequency (RF) signal, and the high frequency multi-coil 205 senses a magnetic resonance signal emitted from the object. Then, the data acquisition unit 410 can sample the sensed magnetic resonance signal on the three-dimensional K space.

The data acquisition unit 410 samples magnetic resonance signals received from the plurality of channel coils included in the high frequency multi-coil 405. Specifically, the data acquisition unit 410 samples the magnetic resonance signal received from the high-frequency multi-coil 405 so that the intervals between the two acquired signals in the first axis direction on the three-dimensional K space are nonuniform, And acquires a plurality of incomplete three-dimensional K-space data corresponding to each of the coils. The sampling operation performed by the data acquisition unit 410 will be described in detail with reference to FIGS. 4B through 7 below.

The image processing unit 420 reconstructs the complete three-dimensional K-space data based on the relationship between the acquired signals included in the incomplete three-dimensional K-space data in the data obtaining unit 410. [ Specifically, the image processor 420 reconstructs signals not acquired in a plurality of incomplete three-dimensional K-space data corresponding to each of the plurality of channel coils to generate a plurality of complete three-dimensional K spatial data. The complete three-dimensional K data acquisition operation of the image processing unit 420 will be described in detail below with reference to FIGS. 8 to 11. FIG.

The control unit 425 controls the overall operation of the magnetic resonance imaging apparatus 400. Specifically, the control unit 425 can set a sampling pattern when the data acquisition unit 410 samples the magnetic resonance image signal on the three-dimensional K space. Here, the sampling pattern refers to a pattern formed by the acquired signals when acquiring a signal at a certain point on the three-dimensional K space and not acquiring signals at other points.

Hereinafter, when the data acquisition unit 410 samples a magnetic resonance image signal on the three-dimensional K space, a sampling pattern for uniformly sampling the interval between two acquired signals in the first axis direction on the three- Is called a " non-uniform sampling pattern ".

Specifically, the controller 425 can set a non-uniform sampling pattern. For example, the control unit 425 can set a specific shape of the non-uniform sampling pattern according to the degree of image quality required in the reconstructed MRI image. In addition, the control unit 435 can set a specific form of the non-uniform sampling pattern according to at least one of the hardware form of the high-frequency multi-coil 405 and the object region.

In detail, the hardware type of the high frequency multi-coil 405 may be the physical size and shape of the high frequency multi-coil 405. Further, the object region may be classified according to the body region such as the head, neck, abdomen, back, ankle, and the like. For example, the high frequency multi-coil 405 used to photograph the head has a helmet shape. As another example, the high frequency multi-coil 405 used for imaging the abdomen or leg has a cylindrical shape. As another example, the high frequency multi-coil 405 used for photographing the back has a plate shape.

Specifically, the shape of the non-uniform sampling pattern may be a shape of the body such as the head, neck, abdomen, back, ankle or the like for the high frequency multi-coil 405, Type, and the like.

In addition, the shape of the non-uniform sampling pattern can be set to an experimentally optimized value.

In addition, the non-uniform sampling pattern can be set by the user. Specifically, the user can set a specific shape of the non-uniform sampling pattern through the user interface unit 460. [ The control unit 425 can control the data acquisition unit 410 to perform the sampling operation according to the non-uniform sampling pattern based on the setting inputted through the user interface unit 460. [

The display unit 450 displays a screen.

In particular, the display unit 450 may be a CRT display, an LCD display, a PDP display, an OLED display, an FED display, an LED display, a VFD display, a DLP (Digital Light Processing) display, a PFD , A transparent display, and the like, and can display a predetermined screen through the above-described various types of displays.

Specifically, the display unit 450 can display a reconstructed magnetic resonance image. Also, the display unit 450 may display a user interface screen for setting a non-uniform sampling pattern. In addition, the display unit 450 may sequentially display images generated in the course of reconstructing a magnetic resonance image. Also, the display unit 450 may display a user interface screen for setting a non-uniform sampling pattern. In addition, the display unit 450 may display a screen including a predetermined non-uniform sampling pattern so that the user can visually recognize a non-uniform sampling pattern applied to the sampling operation.

The user interface unit 460 receives a predetermined request, command, or other data from the user.

For example, the user interface unit 460 may include a mouse, a keyboard, or an input device including hard keys for a predetermined data input. In addition, the user interface unit 460 may be formed of a touch pad. Specifically, the user interface unit 460 includes a touch pad (not shown) coupled with a display panel (not shown) included in the display unit 450, Output the interface screen. When a predetermined command is inputted through the user interface screen, the touch pad detects the predetermined command and recognizes the predetermined command inputted by the user.

In the embodiment, the user interface unit 460 may generate a user interface screen for setting a non-uniform sampling pattern, and may recognize user setting information input through the displayed user interface screen.

The memory 465 may store various data related to restoration of the magnetic resonance image. Specifically, the memory 465 may store a plurality of incomplete three-dimensional K-space data corresponding to each of the plurality of channel coils obtained by the data acquiring unit 410. In addition, the memory 465 may store data calculated in the image reconstruction process, for example, a plurality of complete three-dimensional K spatial data. Also, the memory 465 can store the reconstructed magnetic resonance image.

The memory 465 may store at least one non-uniform sampling pattern. For example, the memory 465 may store a set non-uniform sampling pattern when a non-uniform sampling pattern is set by the user. In addition, the memory 465 may store the uneven sampling pattern set by the control unit 425. [

The communication unit 470 corresponds to the communication unit 70 described with reference to FIG. 2, and therefore, a description overlapping with that of FIG. 2 will be omitted.

In the embodiment, the communication unit 470 can receive the magnetic resonance signals received from each of the plurality of channel coils. Specifically, the communication unit 470 can receive the magnetic resonance signal sensed by the RF receiving unit 38. [ Then, the communication unit 470 can transmit the received magnetic resonance signal to the data acquisition unit 410.

4B is a view showing a three-dimensional K space.

Referring to FIG. 4B, the data acquisition unit 410 may perform a sampling operation on the three-dimensional K space 475. Here, the three-dimensional K space 475 is a space on a spatial frequency domain in three dimensions, and includes a Kx axis 481 corresponding to a frequency encoding gradient, a phase encoding gradient a ky axis 482 corresponding to a slice selection gradient, and a kz axis 483 corresponding to a slice selection gradient. In addition, a plane perpendicular to the Kz axis becomes a Kx-Ky plane 490 on the three-dimensional K space 475, and a plane perpendicular to the Kx axis can be a Ky-Kz plane 480. In FIG. 4B, the K space is centered on the center point 505, the center portion is a low-frequency spatial region, and the outer portion of the K space is a high-frequency spatial region.

The data acquisition unit 410 performs a sampling operation on the three-dimensional K space 475. Specifically, the data acquisition unit 410 can place the signal obtained in the sampling on the three-dimensional K space 475 to acquire the K space data.

In sampling three-dimensional K-space data, it is possible to sample three-dimensional K-space data by sampling a magnetic resonance signal for each of a plurality of slices corresponding to a plurality of Kx-Ky planes. Also, the magnetic resonance signal can be sampled as a whole over the three-dimensional K space regardless of the slice. In addition, sampling methods of three-dimensional K-space data may exist in various ways.

A case where a signal is sampled at every point of the K space is referred to as 'full sampling'. The full sampled three-dimensional K-space data is complete three-dimensional K-space data that does not include points where the signal is not acquired. Here, 'point' means a point corresponding to each pixel included in an image having a desired resolution. A case where a signal is sampled at only a part of the K space without sampling the signal at every point of the K space is called 'under sampling'. The undersampled three-dimensional K-space data is incomplete three-dimensional K-space data including the points where the signals are not acquired.

In the embodiment, the data acquisition unit 410 obtains incomplete three-dimensional K-space data by undersampling the magnetic resonance signal according to the non-uniform sampling pattern, and acquires non-acquired signals from the incomplete three- And obtains the complete three-dimensional K-space data.

5 is a diagram for explaining a magnetic resonance image obtained by sampling a magnetic resonance signal on a three-dimensional K space.

5, (a) shows K-space data 550 in the Ky-Kz plane in three-dimensional K-space data obtained by sampling a magnetic resonance signal on a three-dimensional K-space. In K spatial data 550, a checkpoint 551 on the lattice represents the acquired signals. 5A illustrates a case where a signal is acquired at every point on the lattice in the K-space data 550, that is, when K-space data is acquired through full sampling.

In addition, when the K-space data is acquired through undersampling, in order to recover the magnetic resonance image, it is necessary to recover the signals that are not obtained from the incomplete K-space data, which is undersampled K-space data, to obtain complete K-space data. 5 (b) and 5 (c) show reconstructed magnetic resonance images using complete K-space data.

Referring to FIG. 5B, a magnetic resonance image 510 representing a target object in a sagittal view can be reconstructed using three-dimensional K-space data. For example, the magnetic resonance image 510 according to the sagittal view can be reconstructed using K-space data of the Kx-Ky plane. For example, a slice may be set on a cross section of a target object to be reconstructed, and the magnetic resonance image 510 may be reconstructed using K-space data of the Kx-Ky plane corresponding to the set slice.

Referring to FIG. 5C, a magnetic resonance image 530 is shown showing a subject in a transversal view showing a plane in which the head of the person in the target is cut in the horizontal direction 620. For example, a slice may be set on a section of a target object to be reconstructed, and the M-resonance image 530 may be reconstructed using K-space data of the Ky-Kz plane corresponding to the set slice.

6A is another diagram showing a magnetic resonance imaging apparatus according to the embodiment.

6A, a magnetic resonance imaging apparatus 600 according to the disclosed embodiment includes a gradient magnetic field control unit 601, an RF control unit 603, a high frequency multi-coil 605, a data acquisition unit 610, and an image processing unit 620 ). Here, the data acquisition unit 610 and the image processing unit 620 may correspond to the data acquisition unit 310 and the image processing unit 320 of FIG. 3, respectively. Therefore, the description of the magnetic resonance imaging apparatus 600 that is the same as that in FIG. 3 will be omitted.

The high frequency multi-coil 605, the data acquisition unit 610 and the image processing unit 620 may correspond to the high frequency multi-coil 405, the data acquisition unit 410, and the image processing unit 420 of FIG. have. The magnetic resonance imaging apparatus 600 may further include at least one of the control unit 425, the display unit 450, the user interface unit 460, and the communication unit 470 shown in FIG. 4A. Therefore, a description overlapping with that in FIG. 4A is omitted in the magnetic resonance imaging apparatus 600. FIG.

The oblique magnetic field control unit 601 and the RF control unit 603 may correspond to the oblique magnetic field control unit 54 and the RF control unit 56 of FIG. 1, respectively. Therefore, the description of the magnetic resonance imaging apparatus 600 that is the same as that in FIG. 1 will be omitted.

The RF control unit 603 controls the RF unit 603 to apply a plurality of RF signals corresponding to a plurality of slices to the target object. Hereinafter, the high frequency signal will be referred to as an 'RF signal'. Specifically, the RF controller 603 can adjust the transmission / reception direction of the RF signal and the MR signal. For example, the RF signal may be irradiated to the object through the high frequency multi-coil 605 during the transmission mode, and the MR signal from the object may be received through the high frequency multi-coil 605 during the reception mode. The RF control unit 603 can generate a control signal for controlling the transmission of the RF signal and the reception of the MR signal.

The oblique magnetic field control unit 601 modulates a first direction oblique magnetic field corresponding to the first slice of the plurality of slices into a first state, and modulates the first slope magnetic field corresponding to the second slice adjacent to the first slice Directional gradient magnetic field to a second state different from the first state.

Specifically, the oblique magnetic field control unit 601 can control the oblique coil (24 in Fig. 1) to generate a spatial encoding gradient. In addition, the spatial encoding gradient may include an inclined magnetic field in the X-axis, Y-axis, and Z-axis directions. Specifically, the oblique magnetic field control unit 601 can apply pulse signals to the X, Y, and Z coils that generate gradient magnetic fields in the X-axis, Y-axis, and Z-axis directions orthogonal to each other. Then, an oblique magnetic field in the X-axis, Y-axis, and Z-axis directions can be generated corresponding to the applied pulse signal. The oblique coil (24 in Fig. 1) to which the pulse signal is applied from the oblique magnetic field control unit 601 can provide position information of each part of the object by inducing different resonance frequencies for each part of the object.

Here, the spatial encoding gradient magnetic field can be expressed in a three-dimensional K space (K space), and each of the gradient magnetic fields in the X axis, Y axis, and Z axis directions described above can be expressed by Kx (481), Ky ) And Kz (483) axes. On the other hand, the oblique magnetic fields in the X-axis, Y-axis, and Z-axis directions may correspond to a frequency encoding gradient, a phase encoding gradient, and a slice selection gradient, respectively , Depending on the embodiment, the oblique magnetic field in the frequency encoding direction may correspond to the oblique magnetic field in the Y-axis direction on the K-space, that is, the Ky-axis direction.

1, a bore in the gantry 20 is formed with a static magnetic field and an inclined magnetic field, and an RF signal must be radiated toward the object 10. Then, an MR signal corresponding to the irradiated RF signal is received.

Specifically, the oblique magnetic field control unit 601 controls the pulse signal applied to the first direction coil included in the oblique coil (for example, 24 in FIG. 1) to form the first direction oblique magnetic field in the first slice, State, and a pulse corresponding to the second state can be formed in the second slice.

Specifically, the oblique magnetic field control unit 601 controls the oblique magnetic field control unit 601 so as to obtain incomplete three-dimensional K-space data having the above-described non-uniform sampling pattern, So that it can be controlled to be modulated.

Specifically, the oblique magnetic field control unit 601 can form the phase encoding gradient magnetic field 650 differently for each slice so that incomplete three-dimensional K spatial data having the above-described non-uniform sampling pattern is obtained.

The high frequency multi-coil 605 applies a plurality of RF signals to a target within a spatial encoding gradient including a first direction tilting magnetic field, and generates a first magnetic resonance signal corresponding to the first slice and a second magnetic resonance signal corresponding to the second And receives a magnetic resonance signal corresponding to the slice.

The data acquisition unit 610 samples the first magnetic resonance signal and the second magnetic resonance signal to acquire the incomplete three-dimensional K-space data. Specifically, in order to generate a three-dimensional MR image, a plurality of slices may be set to acquire MR signals for each slice. That is, the MR signal can be sampled by a plurality of slices on the three-dimensional K space.

The image processing unit 620 restores the complete three-dimensional K-space data based on the relationship between the acquired signals included in the incomplete three-dimensional K-space data.

In the magnetic resonance imaging apparatus 600, an MR signal can be received in each of a plurality of channel coils included in the high frequency multi-coil 605, and an incomplete three-dimensional K space corresponding to each of the plurality of channel coils Data can be acquired. In addition, a final magnetic resonance image can be generated using a plurality of complete three-dimensional K-space data corresponding to each of the plurality of channel coils.

The operation of the magnetic resonance imaging apparatus 600 will be described in detail below with reference to FIGS. 6B and 6C.

FIG. 6B is a view for explaining the operation of the magnetic resonance imaging apparatus shown in FIG. 6A.

The magnetic resonance imaging apparatus 600 may receive an MR signal emitted from at least one slice during one repetition time (TR) after the RF signal is applied to the object.

6B, the RF controller 603 controls a plurality of RF signals 622 and 624 corresponding to a plurality of slices to be applied to a target object. Specifically, the RF control unit 603 can sequentially apply a plurality of RF signals 622 and 624 to a target object at predetermined time intervals (for example, 1 TR).

The gradient magnetic field control unit 601 includes a slice selection gradient Gslice 630, a frequency encoding gradient Gfrequency 640, and a phase encoding gradient Gphase , 650 can be controlled.

Referring to FIG. 6B, a high-frequency signal 622 corresponding to the first slice and a high-frequency signal 623 corresponding to the second slice adjacent to the first slice may be sequentially applied to the object. The oblique magnetic field control unit 601 applies a slice selection oblique magnetic field 630 including a pulse 631 for selecting the first slice and a pulse 632 for selecting the second slice, The phase encoding gradient magnetic field 650 may be applied to acquire the frequency encoding gradient magnetic field 640 and the spatial information in the Y axis direction to obtain the Y axis direction spatial information.

Specifically, the oblique magnetic field control unit 601 includes a pulse 641 for acquiring spatial information in the X-axis direction in the first slice and a pulse 642 for acquiring spatial information in the X-axis direction in the second slice A frequency encoding gradient magnetic field 640 can be applied. Further, the oblique magnetic field control unit 601 has a phase including a pulse 656 for acquiring spatial information in the Y-axis direction in the first slice and a pulse 657 for acquiring spatial information in the Y-axis direction in the second slice The encoding gradient magnetic field 650 can be applied.

After the RF signals 622 and 624 are applied into the gantry 20 in which the gradient magnetic field is formed, the high frequency multi-coil 605 can receive the MR signals 651 and 652 emitted from the object. Specifically, the magnetic resonance imaging apparatus 600 can acquire the K spatial data 635 corresponding to the first slice using the MR signal 651 received corresponding to the RF signal 622, 624 using the received MR signal 652 to obtain K spatial data 645 corresponding to the second slice.

The K space data 635 included in the incomplete three-dimensional K space may be data corresponding to the first slice, and the K space data 645 may be data corresponding to the second slice. Specifically, the K spatial data 635 and the K spatial data 645 may be incomplete K spatial data sampled on the Kx-Ky plane, the Ky-Kz plane, or the Kx-Kz plane on the three-dimensional K space.

Specifically, the oblique magnetic field control unit 601 controls the slope magnetic field control unit 601 so that the intervals between the adjacent signals sampled in the lines arranged in the first axis direction in the incomplete three-dimensional K space data are different from each other in the adjacent first and second slices. Directional gradient magnetic field can be modulated.

6B and FIG. 6B, the first and second slices are set on the Kx-Ky plane, the first axis direction is the Y axis or the Ky axis direction, the first direction oblique magnetic field is the phase encoding gradient magnetic field (650) is shown and described as an example.

Specifically, the slope magnetic field control unit 610 controls the slope magnetic field control unit 610 such that the interval between two acquired signals on the line parallel to the phase encoding direction of the incomplete three-dimensional K spatial data becomes a first interval in the first slice, The phase encoding gradient magnetic field can be modulated such that the second gap is different from the first gap.

For example, the oblique magnetic field control unit 601 calculates the interval between adjacent sampled signals in the line 636 arranged in the Ky axial direction in the first axis direction in the K spatial data 635 sampled corresponding to the first slice, The interval between sampled adjacent signals in the line 646 arranged in the Ky axis direction in the first axis direction in the sampled K spatial data 645 corresponding to the second slice is 2, The phase encoding gradient magnetic field 656 corresponding to the first slice and the phase encoding gradient magnetic field 657 corresponding to the second slice can be modulated.

Specifically, the oblique magnetic field control unit 6010 can modulate the pulse shape contained in the first direction oblique magnetic field corresponding to the first slice differently from the first direction oblique magnetic field corresponding to the second slice. For example, the slope magnetic field control unit 601 may change the shape of the pulse included in the phase encoding gradient magnetic field 656 corresponding to the first slice to the shape of the pulse included in the phase encoding gradient magnetic field 657 corresponding to the second slice Can be modulated differently. Specifically, the amplitudes of the pulses included in the phase encoding gradient magnetic field 656 can be set differently in the adjacent plural slices. Specifically, the phase encoding gradient field 656 and the phase encoding gradient field 657 for obtaining K spatial data, such as in the K spatial data 635 and the K spatial data 645 shown in FIG. 6B, A detailed description of the types of pulses included in the phase encoding light delay elements 656 and 657 will be omitted.

As described above, the magnetic resonance imaging apparatus 600 can apply a variable gradient that varies the intervals between lines in a plurality of K spatial data corresponding to a plurality of slices.

FIG. 6C is another drawing for explaining the operation of the magnetic resonance imaging apparatus shown in FIG. 6A. In FIG. 6C, the configuration that is the same as FIG. 6B is denoted by the same reference numerals as those in FIG. 6B, and a description overlapping with FIG. 6B is omitted.

Referring to FIG. 6C, the magnetic resonance imaging apparatus 600 may acquire K spatial data 635 corresponding to the first slice using the MR signal 651 received corresponding to the RF signal 622, The K spatial data 645 corresponding to the second slice can be obtained using the MR signal 652 received corresponding to the RF signal 624. [ The magnetic resonance imaging apparatus 600 may then acquire the K spatial data 655 corresponding to the third slice using the MR signal 653 received corresponding to the RF signal 626 and the RF signal 628 The K spatial data 655 corresponding to the fourth slice can be obtained by using the received MR signal 654 corresponding to the fourth slice. Here, the first, second, third, and fourth slices may be slices adjacent to each other.

The oblique magnetic field control unit 601 may apply a variable gradient that varies the interval between sampled signal lines in each of a plurality of planes on the three-dimensional K space corresponding to a plurality of slices adjacent to each other.

Specifically, the oblique magnetic field control unit 601 modulates and applies the first direction oblique magnetic field to the above-mentioned first state on at least one first slice including the first slice of the plurality of slices, And at least one third slice adjacent to the at least one second slice modulates and applies a first direction oblique magnetic field to the second state in at least one second slice adjacent to the at least one second slice, It is possible to modulate and apply the one-direction oblique magnetic field to the third state different from the first and second states.

For example, the oblique magnetic field control unit 601 modulates the phase encoding oblique magnetic field 656 in the first slice to the first state, and modulates the phase encoding oblique magnetic field 657 in the second and third slices adjacent to the first slice, 658 to the second state, and the fourth slice adjacent to the third slice modulates the phase encoding gradient magnetic field 659 to the third state. In addition, the phase encoding gradient magnetic field can be modulated so that the signal lines obtained from the K spatial data 645 and the K spatial data 655 corresponding to the second and third slices are interleaved.

  Accordingly, in the K-space data 635 corresponding to the first slice, the interval of adjacent signal lines becomes 1, and the K-space data 645 and the K-space data 655 corresponding to the second slice and the third slice, respectively, The interval of adjacent signal lines is 2, and the K space data 665 corresponding to the third slice is infinite (i.e., the MR signal is not sampled in the K space 665).

As described above, the incomplete three-dimensional K-space data obtained by applying a phase gradient gradation gradient variable for each slice will be described in detail below with reference to FIG.

FIG. 6D is another view for explaining the operation of the magnetic resonance imaging apparatus shown in FIG. 6A. In Fig. 6D, the configurations which are the same as those in Figs. 6B and 6C are denoted by the same reference numerals as those in Figs. 6B and 6C, and a description overlapping with those in Figs. 6B and 6C is omitted.

6D, a phase encoding gradient magnetic field 671 corresponding to the first slice may be applied such that the interval of pulses has a first interval so that the K-space data 636 being fully sampled is acquired. The phase encoding gradient magnetic fields 672 and 673 corresponding to the second and third slices can be applied such that the intervals of the pulses have a second interval so that the K spatial data 646 and 656 under sampled are acquired. Here, the first interval is denser than the second interval. And, the phase encoding gradient magnetic field may not be applied in the section corresponding to the fourth slice. Since the K space data 665 corresponding to the fourth slice is not sampled, it is not necessary to apply a gradient magnetic field in the section 680 corresponding to the fourth slice. Therefore, as shown in the dotted line area 674, the pulse of the phase encoding gradient magnetic field 674 may not be applied in the section corresponding to the fourth slice.

In addition, the oblique magnetic field control unit 601 may divide the three-dimensional K space corresponding to the incomplete three-dimensional K space data into a plurality of blocks and modulate the first direction oblique magnetic field for each of the divided three-dimensional K spaces. For example, a variable phase encoding gradient magnetic field can be applied for each of the divided three-dimensional K spaces.

In addition, the oblique magnetic field control unit 601 may modulate at least one of the first state corresponding to the first slice and the second state corresponding to the second slice differently from at least two of the plurality of divided blocks.

The division of the three-dimensional K space will be described in detail below with reference to FIG.

The magnetic resonance imaging apparatus 600 may also apply one RF signal (or RF pulse) 622 during one repetition time (TR) 661, and one repetition time 662 during a period of time during which the RF signals 622, 624 are received. In the former, applying a single RF signal 622 during one repetition time 662 to acquire an MR signal corresponding to one slice may be referred to as a single slice technique. In the latter case, a plurality of RF signals 622 and 624 may be applied during one repetition time 662 to obtain an MR signal corresponding to a plurality of slices, which may be referred to as a multi-slice technique. The magnetic resonance imaging apparatus 600 can use both the single slice technique and the multi-slice technique.

7 is a view for explaining a sampling operation of a magnetic resonance image according to the embodiment.

Referring to FIG. 7A, the three-dimensional K space is represented by Kx axis 704, Ky axis 703, and Kz axis 702 as described above.

7B, K spatial data 710 in the Ky-Kz plane, which is a plane perpendicular to the Kx axis 704, is shown. Specifically, Fig. 7 (b) shows the K-space data (Fig. 7 (b)) in one cross section of the incomplete three-dimensional K-space data obtained by sampling the received MR signal by applying the RF signal and the gradient magnetic field described in Figs. 6 710).

In the embodiment, the K spatial data 710 represents K spatial data in the Ky-Kz plane in one incomplete three-dimensional K spatial data corresponding to one channel coil obtained by sampling in the data obtaining unit 410. [

In the K-space data 710, the obtained signal is represented by a color-marked circle in black as in the case of the 715 signal, and the non-sampled signal, which is the signal at the un sampled point, Indicated by the non-display (717).

The data acquisition unit 410 samples the magnetic resonance signal to obtain incomplete three-dimensional K-space data so that the intervals between the two acquired signals in the first axis direction are non-uniform. Referring to line 705 in the direction of one axis 702 of Figure 7 (b), the distance between two acquired signals in the first axis direction, e.g., Kz axis 702, , A magnetic resonance signal is sampled. 7B, the spacing of acquired signals 724 adjacent to the acquired signal 723 is one row apart, but is obtained adjacent to the acquired signal 724 726 are three columns, and the interval between the obtained signals 727 adjacent to the subsequently acquired signal 726 is one column. Thus, the incomplete three-dimensional K sampled according to the non-uniform sampling pattern In spatial data, the spacing of signals obtained adjacent in the first axis direction, e.g., the line 705 of the Kz axis 702, is not the same, such as one column spacing - three column spacing - one column spacing. , A sampling pattern in a case where the intervals between adjacent two signals are not all the same in a line parallel to the one axial direction can be referred to as a 'non-uniform sampling pattern'. In contrast, in the 'regular sampling pattern' The adjacent two acquired signals have the same interval There.

Further, when each of the lines perpendicular to the first axis, for example, the Kz axis 702, is referred to as "column", the term "column spacing" refers to any column (for example, 711) (E. G., 712). ≪ / RTI > That is, the columns 711 and 712 are spaced apart by 'one column spacing', and the column 712 and the column 715 are spaced apart by 'three column spacings' ) Are spaced apart by " one row spacing ".

Specifically, at least one line 705 formed in the direction parallel to the first axis, e.g., the Kz axis 702, in the incomplete three-dimensional K-space data is the distance between two adjacent acquired signals Can be sampled by this nonuniform nonuniform sampling pattern.

As described above, the non-uniform sampling pattern may refer to a pattern formed by the acquired signals at line 705 parallel to the first axis 702. [

Further, when a pattern formed by the signals obtained in the plurality of lines parallel to the first axis, for example, the Kz axis 702, in the K spatial data 710 is repeated, the non-uniform sampling pattern is a Kz axis A pattern formed by the signals obtained in the block formed by the plurality of lines parallel to the line 702. For example, the patterns formed by the signals obtained in block 706 and block 707 in K spatial data 710 are the same. The spacing between signals obtained in block 706 is not equal and non-uniform. In this case, the pattern formed by the signals obtained in block 706 may be referred to as a non-uniform sampling pattern.

Also, a plurality of obtained line data 711, 712, 713, and 714 parallel to the second axial direction 703 perpendicular to the first axial direction 702 within the incomplete three-dimensional K spatial data may be generated 712, 713, and 714 formed by the plurality of obtained line data 711, 712, 713, and 714. In other words, 720 may be referred to as a non-uniform sampling pattern.

Further, the non-uniform sampling pattern can be repeated a plurality of times in the three-dimensional K space. Specifically, the non-uniform sampling pattern can be repeated throughout the three-dimensional K space. For example, a non-uniform sampling pattern formed by the signals obtained at block 720 may be repeated at block 720 and block 721. [ In addition, the non-uniform sampling pattern may be repeated in some area of the three-dimensional K space.

The data acquisition unit 410 samples the magnetic resonance signals so that the intervals between the two acquired signals in the first axis direction in the entire three-dimensional K space are uneven, so that the plurality of channel coils Three incomplete three-dimensional K-space data can be obtained.

For incomplete three-dimensional K-space data acquired by the data acquisition unit 410, Kx points may be sampled at all Kx points corresponding to the points sampled in the K-space data 710 in the Ky-Kz plane. Referring to FIG. 7C, the K-space data in the Kx-Ky planes are shown in the incomplete three-dimensional K-space data acquired by the data acquiring unit 410. FIG.

7 (c), K spatial data 730 is K spatial data in the Kx-Ky plane corresponding to column 711, and column 711 corresponds to column 731 in the same manner. K spatial data 740 is K spatial data in the Kx-Ky plane corresponding to column 712 and column 712 corresponds to column 741 in the same way. K spatial data 750 is K spatial data in the Kx-Ky plane corresponding to column 713 and column 713 corresponds to column 751 in the same way. K spatial data 760 is K spatial data in the Kx-Ky plane corresponding to column 714 and column 714 corresponds to column 761 in the same way. Also, in FIG. 7C, the line not sampled is shown by the dotted line 742.

7C, the K space data 730, the K space data 740, the K space data 750, and the K space data 760 correspond to the K space data 635 in FIG. 6C, K spatial data 645, K spatial data 655, and K spatial data 665, respectively.

All Kx points corresponding to the sampled points in the K spatial data 710 in the Ky-Kz plane can be sampled. Taking the K spatial data 740 as an example, a non-sampled point 743 in column 741 is not sampled at every point in the column 744 parallel to the Kx axis including point 743, Is sampled at all points in the column 746 parallel to the Kx axis, including the point 745. [

Specifically, the data acquiring unit 410 acquires at least one first plane (e.g., 730) that is to be fully sampled (e.g., 730), at least one second plane that is regularly undersampled (E.g., 740, 050), and at least one third plane that is not sampled (e.g., 760). Here, at least one first plane, at least one second plane, and at least one third plane may be planes that are perpendicular to the first axis (e.g., Kz axis 702) and that are mutually adjacent. And, " regularly undersampling " means that the intervals between acquired signal lines are the same. For example, in the K-space data (e.g., 740, 750) in the second plane, the spacing between the obtained signal lines is all the same in two rows apart. That is, referring to the K-space data (e.g., 740) in the second plane, signals are acquired in row 746 and signals are acquired on a subsequent 748 line without acquiring signals on adjacent lines 747 . Accordingly, the spacing between one line 746 from which the signal is acquired and the other line 748 from which the signal is acquired following one line 746 is two columns apart.

In addition, the incomplete three-dimensional K-space data may be formed by K-space data (e.g., 710) corresponding to a plurality of Ky-Kz planes perpendicular to the Kx-axis 704. Alternatively, the incomplete three-dimensional K spatial data may be formed by K spatial data (e.g., 730) corresponding to a plurality of Kx-Ky planes perpendicular to the Kz axis 702.

8 is a view for explaining a restoration operation of three-dimensional K-space data according to the embodiment. The K spatial data 810 shown in FIG. 8A corresponds to the K spatial data 710 described in FIG. 7B, and the column 816 corresponds to the column 712 shown in FIG. ), So description that is the same as in Fig. 7 will be omitted.

The image processing unit 420 reconstructs the complete three-dimensional K-space data based on the relationship between the acquired signals included in the incomplete three-dimensional K-space data.

Specifically, the image processing unit 420 acquires the first spatial correlation coefficient based on the spatial relationship between the reference signal, which is one signal obtained, and a plurality of other signals obtained, from the incomplete three-dimensional K spatial data. Then, based on the spatial relationship and the first spatial correlation coefficient, at least one undetected signal can be recovered from the incomplete three-dimensional K-space data.

In FIG. 8A, an unacquired signal contained in the K-space data 810 corresponding to one plane included in the incomplete three-dimensional spatial data is restored as an example.

For example, based on the spatial relationship between the reference signal 821, which is one signal obtained from the incomplete three-dimensional K spatial data, and the plurality of other signals 822, 823, 824, and 825 obtained, , And obtains a first spatial correlation coefficient. Here, the spatial relation may mean a relation according to the spatial distance between the reference signal 821 and a plurality of other signals 822, 823, 824, and 825 obtained. Specifically, the spatial relationship can be defined according to the distance between the reference signal 821 and each of the plurality of other signals 822, 823, 824, and 825 obtained. Referring to FIG. 8A, the distance between the reference signal 821 and each of the plurality of other signals 822, 823, 824, and 825 obtained has values 826, 827, 828, and 829 May be referred to as being in a 'first spatial relationship' between the reference signal 821 and the acquired plurality of signals when having the same shape (hereinafter 'X' shape) 815 as in block 820 . 8A illustrates an example in which a plurality of other signals 822, 823, 824, and 825 obtained for the sake of convenience are located on the same Ky-Kz plane. However, the reference signal 821, The obtained signals forming the first spatial relationship with the reference signal 821 may be on a Ky-Kz plane different from the Ky-Kz plane where the reference signal 821 is located. In order to obtain the first spatial correlation coefficient, one of the acquired signals may be set as a reference signal, and a 'first spatial relationship' may be defined as a relation between the set reference signal and other acquired signals.

FIG. 9A is a diagram for explaining acquisition of a spatial correlation coefficient. FIG.

When a first spatial relationship between the reference signal 821 and the acquired plurality of other signals 822, 823, 824 and 825 is defined, the reference signal 821 satisfying the first spatial relationship and the plurality of other signals 822, 823, 824, and 825 to obtain the first spatial correlation coefficient. 9A, the obtained signal 951 corresponds to the obtained plurality of other signals 822, 823, 824 and 825, and the reference signal 952 corresponds to the reference signal 821 And the unacquired signal 953 corresponds to the unacquired signal 841 in the same manner.

Referring to FIG. 9A, left column 910 of the matrix operation is composed of signal values of a plurality of different signals obtained, and right column 920 is composed of signal values of a reference signal. And, Kc represents a spatial correlation coefficient.

In addition, in the right port 920, the plurality of signal values may be signal values at a line (746 in Fig. 7) parallel to the Kx axis including the reference signal 821. [ Also, in the left-hand column 910, signal values at lines parallel to the Kx-axis including each of the plurality of other signals 822, 823, 824, and 825 obtained may be included.

Specifically, the spatial correlation coefficient is a spatial interaction value between signal values measured adjacent to a predetermined signal value, and a target signal value to be estimated can be calculated by matrix-calculating spatial correlation coefficients between adjacent signals have.

9A, left leg 910 may be composed of a plurality of different signals 822, 823, 824 and 825 obtained, and right term 920 may be composed of a signal value 821 of reference signal 821, . Therefore, since the left port 910 and the right port 920 are both obtained signal values, the inverse operation of the matrix shown in (a) of FIG. 9A allows the first spatial correlation coefficient Can be obtained.

Here, the spatial correlation coefficient Kc may be referred to as a convolution kernels or a weighting matrix W. [

In addition, the spatial correlation coefficient (Kc) and the inverse operation of the matrix described above can be obtained or calculated in various ways. Specifically, the inverse operations of Kc and Matrix are described in the article "Introduction to inverse problems in imaging" by the authors Mario Bertero & Patrizia Boccacci, or in the article "Inverse problems theory and methods for model parameter estimation" by author Albert Tarantola , The detailed description is omitted. The formula according to one example for obtaining the spatial correlation coefficient Kc will be described in detail below with reference to FIG.

When the first spatial correlation coefficient is obtained, the image processing unit 420 may restore at least one unacquired signal in the incomplete three-dimensional K spatial data based on the first spatial correlation and the first spatial correlation coefficient. Specifically, when the first signal, which is an unacquired signal included in the incomplete three-dimensional K spatial data, and the acquired plurality of signals satisfy a spatial relationship, the image processing unit 420 generates the first spatial correlation coefficient Signal can be obtained.

Referring to block 850 shown in FIG. 8 (b), an unacquired signal (not shown) having a first spatial relationship having the other signals 852, 853, 854, 855 and the X- 851) as the reference signal and acquire the unacquired signal 851 using the first spatial correlation coefficient. The description of the configuration of the block 850 that overlaps with the block 820 will be omitted.

9A, since the first spatial correlation coefficient Kc is acquired, the signal values of the other signals 852, 853, 854, and 855 acquired in the left port 930 are substituted, 930 and the first spatial correlation coefficient Kc to calculate a value of the right term 940 including the signal value of the reference signal 851 which is an unacquired signal. Here, the 'product' operation may be a multiplication operation between the metrics.

The image processing unit 420 may restore the unacquired signal in the K space data 810 in the manner described in FIG. 9A. Referring to block 840 of FIG. 8A, the unacquired signal 841 and the obtained signals 823, 825, 842, 843 satisfy a first spatial relationship having an X-shape 847 do. Therefore, the unacquired signal 841 is set as the reference signal. Then, as described in FIG. 9A (b), the acquired signals 823, 825, 842, and 844 having the first spatial relationship of the first spatial correlation coefficient and the non-acquired signal 841 and the X- 843 can be used to obtain the unacquired signal 841. [ Subsequently, the image processor 420 sets each of the acquired signals satisfying the first spatial relationship with the obtained signals as reference signals, and restores the unacquired signals. For example, unacquired signal 846 in block 845 may be recovered in the same manner as in block 840. [

When the image processing unit 420 restores the unacquired signals satisfying the first spatial relationship with the obtained signals using the first spatial correlation coefficient, the K spatial data 860 shown in FIG. Can be obtained. In order to obtain the second spatial correlation coefficient for acquiring the unacquired signals contained in the K spatial data 860, the image processing unit 420 performs a spatial correlation process using the spatial correlation between the acquired reference signal, 2 Spatial relationships can be defined.

Specifically, the image processing unit 420 calculates a spatial relationship according to the distance between the reference signal 861, which is one signal obtained in the K spatial data 860, and the other signals 862, 863, 864, and 865, Can be defined. The distance between the reference signal 861 and each of the plurality of other signals 862, 863, 864 and 865 obtained has a value of 871, 872, 873 and 874, (Hereinafter referred to as a 'second spatial relationship' between the reference signal 871 and the obtained plurality of signals).

When the second spatial relationship between the reference signal 861 and the acquired plurality of other signals 862, 863, 864 and 865 is defined, the reference signal 861 satisfying the second spatial relationship and the obtained plurality of other signals 862, 863, 864, 865 to obtain a second spatial correlation coefficient. The second spatial correlation coefficient can be calculated in the same manner as the acquisition of the first spatial correlation coefficient described with reference to FIG. 8 (a) and FIG. 9 (a), and thus detailed description is omitted.

Once the second spatial correlation coefficient is obtained, the image processing unit 420 may recover at least one undetected signal from the incomplete three-dimensional K spatial data based on the second spatial relationship and the second spatial correlation coefficient. Specifically, referring to block 880, a non-acquired signal 881 in a second spatial relationship with the other signals 863, 882, 883, 884 and the '+' Signal, and obtain the undetected signal 881 using the second spatial correlation coefficient. The restoration of the signal value of the unacquired signal 881 can be performed in the same manner as the restoration of the signal value of the unacquired signal 851 described above with reference to FIG. 8B, and thus a detailed description thereof will be omitted.

Subsequently, the image processing unit 420 may set each of the unacquired signals satisfying the second spatial relationship with the signals obtained in the K spatial data 860 as reference signals, and recover the unacquired signals. For example, it may recover all unacquired signals in K spatial data 860, including undetected signal 891 in block 890. Accordingly, the image processing unit 420 can restore the complete three-dimensional K-space data in which the signal values exist at all points in the three-dimensional K space.

As described above, the magnetic resonance imaging apparatus 400 can acquire the spatial correlation coefficient without using the ACS region including the information about the sensitivity to the channel coils or the plurality of lines sampled in the K-space data Can be obtained. Specifically, the magnetic resonance imaging apparatus 400 includes at least one spatial correlation coefficient for restoring an unacquired signal using only the spatial relationship between acquired signals contained in the incomplete three-dimensional K spatial data sampled according to the non-uniform sampling pattern Can be obtained. Then, complete three-dimensional K spatial data can be obtained using at least one spatial correlation coefficient obtained.

9B is a diagram for explaining the setting of a sampling pattern for each block.

9B, the controller 425 may divide the three-dimensional K space 960 into a plurality of blocks, and perform restoration of the unacquired signals on a block-by-block basis. Specifically, the image processing unit 420 divides the incomplete three-dimensional K-space data into a plurality of blocks, and based on the relationship between the obtained signals contained in the divided K-space data, Can be restored.

Referring to FIG. 9B, the three-dimensional K space can be divided into nine blocks. More specifically, the three-dimensional K space 960 can be divided into 3 * 3 = 9 blocks by dividing the block into three blocks in the Ky axis 972 direction and Kz direction 973. 8 and FIG. 9A. As described with reference to FIG. 7, a line parallel to the Kx-axis 704 can be subjected to full sampling. Therefore, full sampling can be performed on a line parallel to the Kx axis 704 without dividing the block in the Kx axis 972 direction and without dividing the block.

Specifically, the non-uniform sampling pattern formed by the line parallel to the first axial direction (e.g., Kx-axis 973) in the incomplete three-dimensional K-space data may be the same in each of the plurality of blocks. On the other hand, the controller 425 may set different non-uniform sampling patterns in at least one of the plurality of blocks.

Specifically, under control of the control unit 425, the data acquisition unit 410 may acquire at least one signal in any one of the plurality of blocks. In addition, under control of the control unit 425, the data acquisition unit 410 may acquire at least one signal in any one of the plurality of blocks. Accordingly, the controller 425 can set the uneven sampling patterns to be different from each other in at least one of the plurality of blocks. That is, the non-uniform sampling pattern formed by the line parallel to the first axis direction in the incomplete three-dimensional K-space data may be different in at least two of the plurality of blocks.

Specifically, the control unit 425 can set the non-uniform sampling pattern corresponding to the block located at the center of the three-dimensional K space to be more denser than the non-uniform sampling pattern corresponding to the block located around the three-dimensional K space. Referring to FIG. 9B, a block 920 positioned at the center of the three-dimensional K space can be set to have a non-uniform sampling pattern such that the acquired signals are included more densely than the remaining blocks included in the three-dimensional K space 960 have.

The setting of the non-uniform sampling pattern will be described in detail below with reference to Figs. 9C to 9F.

Figs. 9C to 9F are diagrams for explaining embodiments for setting a non-uniform sampling pattern. Fig.

9C is a diagram showing an example of incomplete three-dimensional K-space data 985 in the Ky-Kz plane. The control unit 425 can acquire the incomplete three-dimensional K-space data 985 with one non-uniform sampling pattern so that the non-uniform sampling pattern is repeated throughout the three-dimensional K space.

9D is a diagram showing another example of the incomplete three-dimensional K-space data 987 in the Ky-Kz plane. The control unit 425 can set different patterns of the uneven sampling in the center portion 988 of the three-dimensional K space and the region 989 other than the central portion 988. For example, the control unit 435 may be configured to perform non-uniform sampling 988 applied to the center portion 988 of the three-dimensional K space such that the center portion 988 of the three-dimensional K space is acquired with denser densities than the other regions 989. [ The non-uniform sampling pattern applied to the region other than the pattern 989 can be set differently.

In addition, the controller 435 performs full sampling at the center portion 988 of the three-dimensional K space to acquire signals so that the center portion 988 of the three-dimensional K space acquires signals at a density that is denser than the other regions 989 And the other area 989 can acquire signals by applying a non-uniform sampling pattern.

9E is a diagram showing another example of the incomplete three-dimensional K-space data 990 in the Ky-Kz plane. The control unit 425 may divide the three-dimensional K space into a plurality of areas, and apply a non-uniform sampling pattern to the divided areas individually. For example, as shown in the figure, a first region 991 which is a central region of a three-dimensional K space, a second region 992 and a first region 991 adjacent to the first region 991 and a second region 991, 992 may be applied to the peripheral region 993.

For example, the control unit 425 may include a non-uniform sampling pattern applied to the first region 991, a non-uniform sampling pattern applied to the second region 992 to obtain a signal with a denser density at the center of the three- Patterns, and non-uniform sampling patterns applied to the peripheral region 993 can be set differently.

The control unit 425 also applies the uneven sampling pattern applied to the first area 991 and the surrounding area 993 so that the first area 991 acquires signals with a density that is denser than the surrounding area 993. [ Can be set differently from one another. The second area 992 can acquire a signal through full sampling.

The control unit 425 acquires signals in the first area 991 and the surrounding area 993 by applying the same uneven sampling pattern to the first area 991 and the surrounding area 993, ) Can acquire the signal through full sampling.

9F is a diagram showing another example of the incomplete three-dimensional K-space data 990 in the Ky-Kz plane. The control unit 425 divides the center portion of the three-dimensional K space into a plurality of regions 996, 997, 998 and 888 as shown in Fig. 888 may be applied to different non-uniform sampling patterns.

For example, the control unit 425 applies different non-uniform sampling patterns to each of the plurality of divided regions 996, 997, 998, and 888 so that the density of signals obtained as the center of the three- can do.

The control unit 425 acquires signals through the full sampling of the first area 996 and the third area 998 and generates different nonuniform sampling patterns in the second area 997 and the fourth area 999, Can be applied. Specifically, the control unit 425 is configured to apply a non-uniform sampling pattern applied to the second region 996 and a fourth region (e. G., A second region 996) to obtain a signal with a density that is denser than the second region 996 999) can be set differently from one another.

In addition, the control unit 425 may divide the three-dimensional K space 960 into a plurality of blocks, and separately perform restoration operations of signals not obtained in each of the divided blocks. In addition, the controller 425 may perform operations of signals not simultaneously acquired in each of the plurality of blocks. Specifically, the control unit 425 can simultaneously perform the acquisition of the spatial correlation coefficient Kc and the restoration of the unacquired signals in each of the nine blocks shown in FIG. 9B.

In addition, the controller 425 may sequentially acquire the spatial correlation coefficient Kc in the plurality of blocks and perform a restoration operation of the unacquired signals. Specifically, the controller 425 acquires the spatial correlation coefficient Kc and restores the unacquired signals in the first block 981, and subsequently calculates the spatial correlation coefficient Kc in the second block 982 And perform restoration operations of the acquisition and non-acquisition signals. Subsequently, in the third block 983, acquisition of the spatial correlation coefficient Kc and restoration of the unacquired signals are performed. Subsequently, in the fourth block 984, acquisition of the spatial correlation coefficient Kc, And perform a restoration operation of the acquisition signals.

10 is a diagram for explaining the weighting matrix W in detail. Here, the weighting matrix W means the spatial correlation coefficient Kc as described above.

10A, the high frequency multi-coils 405 and 605 are n coils, and the first channel coil (coil # 1) 1011, the second channel coil (coil # 2) 1012, And a coil (coil #N) 1013 as shown in FIG.

The image processor 420 may acquire the spatial correlation coefficient Kc individually in each of the plurality of coils 1011, 1012, and 1013 included in the high-frequency multi-coils 405 and 605.

Specifically, the spatial correlation coefficient Kc corresponding to the first channel is calculated by using the magnetic resonance signal received by the first channel coil 1011. Then, the spatial correlation coefficient Kc corresponding to the second channel is calculated using the magnetic resonance signal received by the second channel coil 1012. Next, the spatial correlation coefficient Kc corresponding to the N-th channel is calculated by using the magnetic resonance signal received by the N-th channel coil 1013.

As described above, when Kc is referred to as a weighting matrix W, the weighting matrix W is divided into a block group (g), a coil number (j), and an acceleration factor Number of coils (Nc), and the like.

Referring to FIG. 10 (b), a formula for obtaining the spatial correlation coefficient Kc described in FIG. 9A is shown. Specifically, the equation shown in FIG. 10 (b) is an example of a formula that can be used to obtain the spatial correlation coefficient Kc.

Referring to the equation shown in FIG. 10B, left column 450, right column 470, and weight matrix 460 each include a right column 920 of the matrix operation shown in FIG. 9A (a) And correspond to the left term 910 of the operation and the spatial correlation coefficient Kc, respectively.

10 (c) is a view for explaining the factors used in the equation shown in FIG. 10 (b).

Referring to FIGS. 10 (b) and 10 (c), g denotes a block group. When dividing the incomplete three-dimensional K spatial data obtained in the three-dimensional K space corresponding to one channel coil (for example, 960 in FIG. 9B) into a plurality of blocks, a block (for example, 981) Lt; / RTI >

For example, let us assume that incomplete three-dimensional K-space data obtained by sampling a magnetic resonance signal received from one channel coil has a size of 256 * 256 * 256. In this case, 256 lines are formed on the kx axis, 256 lines on the Ky axis, and 256 lines on the Kz axis. In a line that is sampled in the Kx axis direction and is parallel to the Kz axis direction as shown in Fig. 7 (c) The interval between two adjacent signals can be sampled non-uniformly. As shown in Fig. 9B, when divided into three blocks in the Ky direction and divided into three blocks in the Kz direction, 256/3 = about 85 lines in the Ky direction in one block, And 256/3 = approximately 85 lines in the Kz direction.

In the above example, since the number of blocks is 9, g can have a value of 1 to 9. [ j denotes a coil number. When the high frequency multi-coil 405 includes a plurality of coils, j denotes the number of coils included in the high-frequency multi-coil 405. That is, in the example shown in FIG. 10A, the coil number j may have a value of 1 to N (N is a natural number).

B is the block size. Specifically, By means the block size in the Ky axis direction, and Bz means the block size in the Kz direction. In the above example, By may be 85, which is the number of lines included in one block, and Bz may be the number of lines included in one block.

n denotes a block number in a group, and denotes a block number of a predetermined block included in one incomplete three-dimensional K-space data corresponding to one coil. Specifically, the block number of the block 981 arranged first in the three-dimensional K space 960 may be one, and the block number of the block 982 arranged second may be two.

Nc denotes the number of coils included in the high frequency multi-coil 405. [ Nb is the number of blocks adjacent to the current block. Specifically, the number of blocks arranged adjacent to the current block (for example, 920) in the K space data 310 is the number of blocks excluding the current block 920 in the three-dimensional K space 960 Can be eight.

Nr and Nl denote the number of data located on the left and right of the selected point in the frequency encoding data arranged in the Kx direction in the K space. r is the acceleration factor. M (by, r) or M (bz, r) refers to a non-uniform sampling pattern in which the acceleration factor in the b block is a non-uniform sampling mask having an r value.

Specifically, Sg, j shown in FIG. 10 (b) represents a signal value at a selected one point in a predetermined block in incomplete three-dimensional K-space data, and Sg, c represents a signal value obtained at other points in a predetermined block Signal values. And, Wg, j, and r mean the weighting matrix applied in the block, which means the above spatial correlation coefficient (Kc). 10 (b), Sg, j (Ky + By (ny-1), Kx, Kz + Bz (nz-1)) 1050 are ky + By -1) and Kz + Bz (nz-1) in the Kz-axis direction, and the signal values of the above-mentioned reference signal are shown. Then, Sg, c (Ky + M (by, r), Kx + h * delta Kx and Kz + M (bz, r) 1070 represent the obtained signals in spatial relationship with the signal values in the reference line data Signal value.

Illustratively, the weighted matrix 1060, which is the spatial correlation coefficient Kc, can be calculated using the equation shown in Figure 10 (b), and the unacquired signals also can be computed using the equation . ≪ / RTI > 11 is a diagram for explaining a restoration operation of a magnetic resonance image according to the embodiment.

The image processor 420 reconstructs the complete three-dimensional K-space data for each of the plurality of channel coils included in the high-frequency multi-coil 405, restores a plurality of complete three-dimensional K-space data corresponding to the plurality of channel coils can do.

11, when the high frequency multi-coil 405 includes n channel coils COIL1 to COIL N, the image processing unit 420 includes n incomplete three-dimensional K-space corresponding to n channel coils It is possible to perform a restoration operation of the unacquired signals in the data 1110 and 1120. Accordingly, n complete three-dimensional K spatial data 1115 and 1125 corresponding to each of the n channel coils COIL1 to COIL N can be obtained. In FIG. 11, the non-uniform sampling pattern in the incomplete three-dimensional K-space data (for example, 1110) is shown as an example of the same sampling pattern as the non-uniform sampling pattern shown in FIG.

The image processor 420 performs spatial transform of a plurality of complete three-dimensional K spatial data 1115 and 1125 corresponding to each of the plurality of channel coils to generate a plurality of channel-by-channel magnetic resonance images 1117, 1127, and obtain the final magnetic resonance image 1150 using the plurality of channel-specific MRI images 1117, 1127.

Specifically, the image processor 420 performs spatial transform of a plurality of complete three-dimensional K-space data 1115 and 1125 to generate a plurality of channel-specific MRI images 1117 and 1127, The three-dimensional MRI image 1150 can be reconstructed by summing the MRI images 1117 and 1127.

Specifically, in order to convert a plurality of complete three-dimensional K spatial data 1115 and 1125 from a frequency domain to a spatial domain, Inverse Fourier Transform or Inverse Fast Fourier Transform may be performed. A final MRI image 1150 can be acquired by performing a sum of squares or a complex sum of the inverse fast Fourier transformed channel-by-channel MRI images 1117 and 1127.

12 is a view showing reconstructed magnetic resonance images according to an embodiment.

Referring to FIG. 12A, aliasing artifacts are dispersed in the reconstructed final magnetic resonance image 1210 based on incomplete three-dimensional K-space data sampled by a non-uniform sampling pattern.

Referring to FIG. 12B, an image 1250 obtained by performing image enhancement processing on the final magnetic resonance image 1210 is shown.

In order to improve the quality of the final magnetic resonance image when the final MRI image is generated using the reconstructed K spatial data by restoring the undersampled K spatial data by generating the reconstructed K spatial data, image enhancement processing such as noise reduction processing, edge enhancement processing, and contrast enhancement processing can be performed.

When the aliasing defect is dispersed in the image, aliasing defects existing in the magnetic resonance image can be removed through subsequent image enhancement processing, thereby minimizing aliasing defects remaining. Accordingly, in the embodiment, it is possible to finally obtain the image 1250 in which the noise or the defect is reduced.

13 is a flowchart showing a method of imaging a magnetic resonance image according to the embodiment. The imaging method of the magnetic resonance imaging according to the embodiment includes the same configuration features and technical ideas as the magnetic resonance imaging apparatus of the embodiment described with reference to Figs. 1 to 12. Fig. Therefore, a description overlapping with those in Figs. 1 to 12 will be omitted.

13, a magnetic resonance imaging imaging method 1300 is a method of imaging a magnetic resonance signal received from each of a plurality of channel coils included in a high-frequency multi-coil, Dimensional K-space data corresponding to each of the plurality of channel coils is sampled by non-uniformly sampling the intervals between the obtained signals (Step 1310). Since the operation of step 1310 is the same as that of the data acquisition unit 410, detailed description is omitted.

Next, based on the relationship between the obtained signals included in the incomplete three-dimensional K-space data, the complete three-dimensional K-space data is reconstructed (operation 1320). Since the operation of step 1320 is the same as that of the image processing unit 420, a detailed description thereof will be omitted.

The magnetic resonance imaging apparatus and the magnetic resonance imaging method according to the embodiment of the present invention can improve the image quality of the reconstructed magnetic resonance imaging. More specifically, by obtaining three-dimensional K-space data undsampled at a nonuniform sampling interval, deterioration of image quality due to aliasing defects can be prevented, and image quality of a reconstructed MRI image can be improved.

In addition, the magnetic resonance imaging apparatus and the magnetic resonance imaging method according to one or more embodiments of the present invention can quickly acquire a magnetic resonance image by acquiring three-dimensional K-space data by undersampling at irregular intervals. Also, spatial correlation coefficients can be acquired without using additional calibration signals such as the Grafu technique or using Coil Sensitivity Maps with additional coil information such as SMASH, The resonance image can be obtained quickly.

In addition, the magnetic resonance imaging apparatus and the magnetic resonance imaging method according to the embodiments of the present invention are capable of sampling a K-space on a block-by-block basis, thereby obtaining a strength in image restoration in a low frequency region and a high- .

The above-described embodiments of the present invention can be embodied in a general-purpose digital computer that can be embodied as a program that can be executed by a computer and operates the program using a computer-readable recording medium.

The computer readable recording medium may be a magnetic storage medium such as a ROM, a floppy disk, a hard disk, etc., an optical reading medium such as a CD-ROM or a DVD and a carrier wave such as the Internet Lt; / RTI > transmission).

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

20: Gantry
22: Main magnet
24: Inclined coil
26: RF coil
28: Table
30: Signal transmission /
32: gradient magnetic field amplifier
34: Transmitting / receiving switch
36: RF transmitter
38: RF receiver
40: Monitoring section
42: System monitoring section
44: object monitoring unit
46:
48:
50:
52: Sequence control section
54: Oblique magnetic field control unit
56: RF control section
58: Gantry control section
60:
62:
64:
66:
200: Magnetic Resonance Imaging Device
205: High frequency multi-coil
210:
230:
250:

Claims (35)

The magnetic resonance signal received in each of the plurality of channel coils included in the high frequency multi-coils is sampled by sampling the two acquired signals adjacent to each other in the first axis direction on the three-dimensional K- Dimensional K-space data corresponding to each of the plurality of incomplete three-dimensional K-space data; And
And an image processing unit for restoring the complete three-dimensional K-space data based on the spatial relationship between the obtained signals contained in the incomplete three-dimensional K-space data,
Wherein the incomplete K spatial data comprises at least one first plane that is to be fully sampled, at least one second plane that is regularly undersampled, and at least one non-sampled second plane that is perpendicular to the first axis and that are mutually adjacent planes, Dimensional K spatial data by sampling the magnetic resonance signal in a plurality of planes including three planes perpendicular to the first axis and mutually adjacent to each other to obtain the incomplete three-dimensional K-space data. The apparatus of claim 1, wherein the data obtaining unit
Dimensional K space data is sampled by sampling the magnetic resonance signal such that the interval between two acquired signals in the first axis direction in the entire three-dimensional K space is non-uniform, thereby obtaining the incomplete three-dimensional K- Imaging device. The method according to claim 1,
The non-uniform sampling pattern formed by sampling the magnetic resonance signals line by line so that the intervals between two obtained signals in the first axis direction on the three-dimensional K space become uneven, is characterized in that each of the plurality of channel coils And the magnetic field is repeated a plurality of times on the corresponding three-dimensional K space. The method according to claim 1,
The data obtaining unit
Acquiring line data that is completely sampled and parallel to a second axis direction perpendicular to the first axis so that the interval between two acquired signals in the first axis direction on the three-dimensional K space is uneven, Obtain incomplete three-dimensional K-space data,
Wherein at least one line formed in the direction parallel to the first axis in the incomplete three-dimensional K-space data forms a non-uniform sampling pattern in which the interval between two adjacent acquired signals is non-uniform. Imaging device. The method according to claim 1,
Wherein a plurality of obtained line data parallel to a second axial direction perpendicular to the first axis direction in the incomplete three-dimensional K spatial data is obtained by dividing the interval between two obtained line data of the plurality of obtained line data Thereby forming the non-uniform non-uniform sampling pattern. The apparatus of claim 1, wherein the image processing unit
Acquiring a first spatial correlation coefficient based on a spatial relationship between the obtained reference signal and a plurality of other signals acquired in the incomplete three-dimensional K spatial data; And reconstructs at least one unacquired signal from the incomplete three-dimensional K-space data based on the acquired three-dimensional K-space data. 7. The apparatus of claim 6, wherein the image processing unit
And acquiring the first signal based on the first spatial correlation coefficient if the first signal, which is an unacquired signal included in the incomplete three-dimensional K spatial data, and the acquired plurality of signals satisfy the spatial relationship, Magnetic resonance imaging apparatus. The apparatus of claim 1, wherein the image processing unit
Dimensional K space data is divided into a plurality of blocks and the complete three-dimensional K space data is reconstructed on a block-by-block basis based on a relationship between the obtained signals contained in the divided K space data. Resonance imaging device. 9. The method of claim 8,
Wherein the non-uniform sampling pattern formed by the plurality of line data parallel to the second axis direction perpendicular to the first axis direction in the incomplete three-dimensional K space data is the same in each of the plurality of blocks. Device. 10. The apparatus of claim 9, wherein the data obtaining unit
And acquires at least one signal in any one of the plurality of blocks. 10. The apparatus of claim 9, wherein the data obtaining unit
Wherein at least one of the plurality of blocks acquires at least one signal in any one of the plurality of blocks. 9. The method of claim 8,
Wherein the non-uniform sampling pattern formed by the line parallel to the first axis direction in the incomplete three-dimensional K spatial data is different in at least two of the plurality of blocks. 13. The method of claim 12,
And a controller for setting a non-uniform sampling pattern corresponding to a block located at the center of the three-dimensional K space more densely than a non-uniform sampling pattern corresponding to a block located around the three-dimensional K space Magnetic resonance imaging apparatus. The image processing apparatus according to claim 1,
And reconstructs the complete three-dimensional K-space data for each of the plurality of channel coils to recover a plurality of complete three-dimensional K-space data corresponding to the plurality of channel coils. 15. The apparatus of claim 14, wherein the image processing unit
Dimensional K spatial data by spatial transforming the plurality of complete three-dimensional K spatial data, and summing the plurality of complete three-dimensional K spatial data subjected to spatial transformation to recover the 3D magnetic resonance image. Imaging device. A high frequency multi-coil including a plurality of channel coils receiving a radio frequency (RF) applied to a target and receiving a magnetic resonance signal corresponding to an applied high frequency and emitted from a nuclear spin of the target;
Sampling the magnetic resonance signal so that the interval between two acquired signals in the first axis direction on the three-dimensional K space becomes non-uniform, and acquiring a plurality of incomplete three-dimensional K space data corresponding to each of the plurality of channel coils A data acquiring unit for acquiring data; And
And an image processing unit for restoring the complete three-dimensional K-space data based on the spatial relationship between the obtained signals contained in the incomplete three-dimensional K-space data,
Wherein the incomplete K spatial data comprises at least one first plane that is to be fully sampled, at least one second plane that is regularly undersampled, and at least one non-sampled second plane that is perpendicular to the first axis and that are mutually adjacent planes, Dimensional K spatial data by sampling the magnetic resonance signal in a plurality of planes including three planes perpendicular to the first axis and mutually adjacent to each other to obtain the incomplete three-dimensional K-space data. The magnetic resonance signal received in each of the plurality of channel coils included in the high frequency multi-coils is sampled by sampling the two acquired signals adjacent to each other in the first axis direction on the three-dimensional K- Acquiring a plurality of incomplete three-dimensional K-space data corresponding to each of the three-dimensional K-space data; And
And reconstructing the complete three-dimensional K-space data based on the spatial relationship between the acquired signals contained in the incomplete three-dimensional K-space data,
Wherein the incomplete K spatial data comprises at least one first plane that is to be fully sampled, at least one second plane that is regularly undersampled, and at least one non-sampled second plane that is perpendicular to the first axis and that are mutually adjacent planes, Dimensional K-space data by sampling the magnetic resonance signal in a plurality of planes including three planes perpendicular to the first axis and adjacent to each other to obtain the incomplete three-dimensional K-space data. 17. The method of claim 16, wherein obtaining
And acquiring a plurality of the incomplete three-dimensional K-space data by sampling the magnetic resonance signal so that an interval between two acquired signals in the first axis direction in the entire three-dimensional K space is uneven, Of the magnetic resonance image. 18. The method of claim 17, wherein obtaining
A plurality of planes including at least one first plane that is fully sampled, at least one second plane that is regularly undersampled, and at least one third plane that is not sampled and that are perpendicular to the first axis and that are adjacent to each other And sampling the magnetic resonance signal to obtain the incomplete three-dimensional K-space data. 18. The method of claim 17,
The non-uniform sampling pattern formed by sampling the magnetic resonance signals line by line so that the intervals between two obtained signals in the first axis direction on the three-dimensional K space become uneven, is characterized in that each of the plurality of channel coils Dimensional space is repeated a plurality of times on the corresponding three-dimensional K space. 18. The method of claim 17,
The step of acquiring a plurality of incomplete three-dimensional K spatial data
Acquiring line data that is completely sampled and parallel to a second axis direction perpendicular to the first axis so that the interval between two acquired signals in the first axis direction on the three-dimensional K space is uneven, Acquiring incomplete three-dimensional K spatial data,
Wherein at least one line formed in the direction parallel to the first axis in the incomplete three-dimensional K-space data forms a non-uniform sampling pattern in which the interval between two adjacent acquired signals is non-uniform. A method of imaging an image. 18. The method of claim 17,
Acquiring a first spatial correlation coefficient based on a spatial relationship between a reference signal, which is one signal obtained, and a plurality of other signals obtained in the incomplete three-dimensional K spatial data; And
And reconstructing at least one non-acquired signal in the incomplete three-dimensional K-space data based on the spatial relationship and the first spatial correlation coefficient. 23. The method of claim 22, wherein restoring the at least one undetected signal comprises:
Acquiring the first signal based on the first spatial correlation coefficient when the first signal, which is an unacquired signal included in the incomplete three-dimensional K spatial data, and the acquired plurality of signals satisfy the spatial relationship, And imaging the magnetic resonance image. 18. The method of claim 17,
Dividing the incomplete three-dimensional K-space data into a plurality of blocks; And
And reconstructing the complete three-dimensional K-space data on a block-by-block basis based on the relationship between the obtained signals contained in the divided K-space data. 25. The method of claim 24,
Wherein the non-uniform sampling pattern formed by the line parallel to the first axis direction in the incomplete three-dimensional K spatial data is the same in each of the plurality of blocks. 25. The method of claim 24,
Wherein a non-uniform sampling pattern formed by a plurality of line data parallel to a second axial direction perpendicular to the first axis direction in the incomplete three-dimensional K spatial data is different in at least two of the plurality of blocks Imaging method of magnetic resonance imaging. 27. The method of claim 26, wherein obtaining
And setting a non-uniform sampling pattern corresponding to a block located at the center of the three-dimensional K space to be denser than a non-uniform sampling pattern corresponding to a block located around the three-dimensional K space A method of imaging a magnetic resonance imaging. 18. The method of claim 17,
The restoring step
And reconstructing the complete three-dimensional K-space data for each of the plurality of channel coils,
The imaging method of the magnetic resonance imaging
And reconstructing a plurality of complete three-dimensional K-space data corresponding to the plurality of channel coils. 29. The method of claim 28,
Spatial transforming the plurality of complete three-dimensional K spatial data; And
Further comprising the step of summing the plurality of complete three-dimensional K-space data subjected to spatial transformation to reconstruct a 3D magnetic resonance image. A first slice magnetic field corresponding to a first slice of a plurality of slices is modulated into a first state and a second slice adjacent to the first slice and a third slice adjacent to the second slice And a fourth slice adjacent to the third slice among the plurality of slices modulates the first slope magnetic field in the third direction different from the first state and the second state, An oblique magnetic field control unit for modulating the magnetic field in a state;
Applying a plurality of high-frequency signals to a target within a spatial encoding gradient including the first direction gradient magnetic field, applying a first magnetic resonance signal corresponding to the first slice and a second magnetic resonance signal corresponding to the second slice A high frequency multi-coil for receiving a corresponding second magnetic resonance signal;
A data acquisition unit for sampling the first magnetic resonance signal and the second magnetic resonance signal to obtain incomplete three-dimensional K-space data; And
And an image processing unit for restoring the complete three-dimensional K-space data based on the spatial relationship between the obtained signals contained in the incomplete three-dimensional K-space data,
Wherein the data obtaining unit comprises: at least one first plane that is fully sampled and corresponds to the first slice; at least one second plane that is regularly undersampled and corresponds to the second slice and the third slice; Dimensional K spatial data by sampling the magnetic resonance signal at a plurality of planes including at least one third plane corresponding to the fourth slice and perpendicular to the first axis and mutually adjacent to each other, Magnetic resonance imaging apparatus. 31. The apparatus of claim 30, wherein the oblique magnetic field control unit
Wherein the first direction oblique magnetic field is modulated such that the interval between adjacent signals sampled in the line arranged in the first axis direction in the incomplete three-dimensional K spatial data is different between the first slice and the second slice, Magnetic resonance imaging apparatus. 31. The apparatus of claim 30, wherein the oblique magnetic field control unit
Wherein the shape of the pulse included in the first directional gradient magnetic field corresponding to the first slice is modulated differently from the direction of the first directional gradient magnetic field corresponding to the second slice. 31. The method of claim 30,
Wherein the first direction oblique magnetic field is a phase-encoded oblique magnetic field,
The oblique magnetic field control unit
Wherein an interval between adjacent acquired signals on a line parallel to the phase encoding direction of the incomplete three-dimensional K spatial data is a first interval in the first slice and a second interval in the second slice, Wherein the first directional gradient magnetic field is modulated so that the first directional gradient magnetic field becomes an interval. 31. The apparatus of claim 30, wherein the oblique magnetic field control unit
Dimensional K space corresponding to the incomplete three-dimensional K space data is divided into a plurality of blocks, and the first direction gradient magnetic field is modulated for each of the divided three-dimensional K spaces. 35. The apparatus of claim 34, wherein the oblique magnetic field control unit
Wherein at least one of the first state corresponding to the first slice and the second state corresponding to the second slice is modulated differently in at least two of the plurality of blocks.

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