JP2023180045A - Medical data processing device, medical data processing method, medical data processing program and magnetic resonance imaging unit - Google Patents

Abstract

To improve visibility of signals.SOLUTION: A medical data processing device according to an embodiment comprises a setting unit and a determining unit. The setting unit sets an enlarged interest region including: an interest region; and a region in the surrounding of the interest region. The determining unit determines an OVS (Outer Volume Suppression) pattern for suppressing signals and being applied to a region outside of the enlarged interest region.SELECTED DRAWING: Figure 1

Description

Embodiments disclosed in this specification and the drawings relate to a medical data processing device, a medical data processing method, a medical data processing program, and a magnetic resonance imaging device.

There is a technique called OVS (Outer Volume Suppression) which applies a saturation signal as a pre-pulse to a signal from an unnecessary signal source outside the region of interest to suppress the signal from outside the region of interest.
However, since OVS is generally mechanically set for a rectangular region of interest, it may not be set properly depending on the size and position of the region of interest, and signals within the region of interest may not match signals outside the region of interest. There is a problem in that signals from unnecessary signal sources are likely to mix in.

Japanese Patent Application Publication No. 2016-187607

Hidenori Takeshima, “Deep Learning and Its Application to Function Approximation for MR in Medicine: An Overview”, [Online], September 17, 2021, Magnetic Resonance in Medical Sciences, [Retrieved January 11, 2022], Internet < URL: https://doi.org/10.2463/mrms.rev.2021-0040＞

One of the problems to be solved by the embodiments disclosed in this specification and the drawings is that it is possible to flexibly set a region in which a signal is to be suppressed or a region to be measured. However, the problems to be solved by the embodiments disclosed in this specification and the drawings are not limited to the above problems. Problems corresponding to the effects of each configuration shown in the embodiments described later can also be positioned as other problems.

The medical data processing device according to this embodiment includes a setting section and a determining section. The setting unit sets an expanded region of interest including a region of interest and a region around the region of interest. The determination unit determines an OVS (Outer Volume Suppression) pattern for suppressing a signal to be applied to a region outside the expanded region of interest.

FIG. 1 is a block diagram showing a magnetic resonance imaging apparatus according to this embodiment. FIG. 2 is a flowchart showing the operation of a magnetic resonance imaging apparatus including a medical data processing apparatus. FIG. 3 is a diagram showing an example of an enlarged region of interest. FIG. 4 is a diagram showing a first example of an OVS pattern set for the enlarged region of interest in FIG. 3. FIG. 5 is a schematic diagram showing an MRS pulse sequence including an OVS pulse. FIG. 6 is a diagram showing a second example of the OVS pattern set for the third enlarged region of interest. FIG. 7 is a diagram illustrating an example of generation of a trained model that estimates an expanded region of interest from a region of interest. FIG. 8 is a diagram showing an example in which the region of interest is set to a desired region shape.

Hereinafter, a medical data processing apparatus, a medical data processing method, a medical data processing program, and a magnetic resonance imaging apparatus according to the present embodiment will be described with reference to the drawings. In the following embodiments, parts with the same reference numerals perform similar operations, and redundant explanations will be omitted as appropriate. Hereinafter, one embodiment will be described using the drawings.

The medical data processing device according to this embodiment processes magnetic resonance signals (hereinafter referred to as MR signals) collected by a magnetic resonance imaging device. The medical data processing device may be incorporated into the magnetic resonance imaging device or may be separate from the magnetic resonance imaging device.

FIG. 1 is a block diagram showing a configuration example of a magnetic resonance imaging apparatus 1 according to this embodiment. As shown in FIG. 1, the magnetic resonance imaging apparatus 1 includes a gantry 11, a bed 13, a gradient magnetic field power source 21, a transmitting circuit 23, a receiving circuit 25, a bed driving device 27, a sequence control circuit 29, and a medical data processing device (host computer )50.

The pedestal 11 has a static magnetic field magnet 41 and a gradient magnetic field coil 43. The static magnetic field magnet 41 and the gradient magnetic field coil 43 are housed in the casing of the pedestal 11. A hollow bore is formed in the casing of the pedestal 11 . A transmitting coil 45 and a receiving coil 47 are arranged within the bore of the pedestal 11.

The static magnetic field magnet 41 has a hollow, substantially cylindrical shape, and generates a static magnetic field substantially inside the cylinder. As the static field magnet 41, for example, a permanent magnet, a superconducting magnet, a normal conducting magnet, or the like is used. Here, the central axis of the static magnetic field magnet 41 is defined as the Z-axis, the axis vertically orthogonal to the Z-axis is defined as the Y-axis, and the axis horizontally orthogonal to the Z-axis is defined as the X-axis. The X-axis, Y-axis, and Z-axis constitute an orthogonal three-dimensional coordinate system.

The gradient magnetic field coil 43 is a coil unit that is attached inside the static magnetic field magnet 41 and formed in a hollow, substantially cylindrical shape. The gradient magnetic field coil 43 receives current from the gradient magnetic field power supply 21 and generates a gradient magnetic field. More specifically, the gradient magnetic field coil 43 has three coils corresponding to the X-axis, Y-axis, and Z-axis that are orthogonal to each other. The three coils form a gradient magnetic field whose magnetic field strength changes along each of the X-axis, Y-axis, and Z-axis. The gradient magnetic fields along the X, Y, and Z axes are combined to form a mutually orthogonal slice selection gradient magnetic field Gs, phase encode gradient magnetic field Gp, and frequency encode gradient magnetic field Gr in a desired direction. The slice selection gradient magnetic field Gs is used to arbitrarily determine an imaging section (slice). The phase encoding gradient magnetic field Gp is used to change the phase of a magnetic resonance signal (hereinafter referred to as an MR signal) depending on the spatial position. The frequency encode gradient magnetic field Gr is used to change the frequency of the MR signal depending on the spatial position. In the following description, it is assumed that the gradient direction of the slice selection gradient magnetic field Gs is the Z axis, the gradient direction of the phase encode gradient magnetic field Gp is the Y axis, and the gradient direction of the frequency encode gradient magnetic field Gr is the X axis.

The gradient magnetic field power supply 21 supplies current to the gradient magnetic field coil 43 according to a sequence control signal from the sequence control circuit 29 . The gradient magnetic field power supply 21 supplies current to the gradient magnetic field coils 43, thereby causing the gradient magnetic field coils 43 to generate gradient magnetic fields along the X, Y, and Z axes. The gradient magnetic field is applied to the subject P while being superimposed on the static magnetic field formed by the static magnetic field magnet 41.

The transmitting coil 45 is disposed, for example, inside the gradient magnetic field coil 43, receives current from the transmitting circuit 23, and generates a high frequency pulse (hereinafter referred to as an RF pulse).

The transmitting circuit 23 supplies current to the transmitting coil 45 in order to apply an RF pulse for exciting target protons present in the subject P to the subject P via the transmitting coil 45. The RF pulse oscillates at a resonant frequency specific to the target proton and excites the target proton. An MR signal is generated from the excited target protons and detected by the receiving coil 47. The transmitting coil 45 is, for example, a whole body coil (WB coil). Whole body coils may be used as transmit and receive coils.

The receiving coil 47 receives an MR signal emitted from target protons present in the subject P under the action of the RF pulse. The receiving coil 47 has a plurality of receiving coil elements capable of receiving MR signals. The received MR signal is supplied to the receiving circuit 25 via wire or wirelessly. Although not shown in FIG. 1, the receiving coil 47 has a plurality of receiving channels implemented in parallel. The reception channel includes a reception coil element that receives the MR signal, an amplifier that amplifies the MR signal, and the like. The MR signal is output for each receiving channel. The total number of reception channels and the total number of reception coil elements may be the same, or the total number of reception channels may be greater or less than the total number of reception coil elements.

The receiving circuit 25 receives the MR signal generated from the excited target protons via the receiving coil 47. The receiving circuit 25 processes the received MR signal to generate a digital MR signal. Digital MR signals can be expressed in k-space defined by spatial frequencies. Therefore, hereinafter, the digital MR signal will be referred to as k-space data. K-space data is an example of an MR acquisition signal. The k-space data is supplied to the medical data processing device 50 via wire or wireless.

Note that the above-mentioned transmitting coil 45 and receiving coil 47 are merely examples. Instead of the transmitting coil 45 and the receiving coil 47, a transmitting/receiving coil having a transmitting function and a receiving function may be used. Moreover, the transmitting coil 45, the receiving coil 47, and the transmitting/receiving coil may be combined.

A bed 13 is installed adjacent to the pedestal 11. The bed 13 has a top plate 131 and a base 133. A subject P is placed on the top plate 131. The base 133 supports the top plate 131 so as to be slidable along each of the X-axis, Y-axis, and Z-axis. The bed driving device 27 is accommodated in the base 133. The bed driving device 27 moves the top plate 131 under control from the sequence control circuit 29. The bed driving device 27 may include any motor such as a servo motor or a stepping motor.

The sequence control circuit 29 has, as hardware resources, a processor such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit), and a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory). The sequence control circuit 29 synchronously controls the gradient magnetic field power supply 21, the transmitter circuit 23, and the receiver circuit 25 based on the data collection conditions set by the processing circuit 51, and performs data collection on the subject according to the data collection conditions. P to collect k-space data regarding the subject P. The sequence control circuit 29 is an example of a sequence control section.

The sequence control circuit 29 according to this embodiment executes data collection for MR spectroscopy (hereinafter also referred to as MRS), which is a type of chemical shift measurement. Chemical shift measurement is a technology that measures chemical shifts, which are minute differences in the resonance frequencies of target protons such as hydrogen nuclei, which occur in response to differences in chemical environments. MRS includes a single voxel method in which data is collected for a single voxel and a multi-voxel method in which data is collected in multiple voxels, and the present embodiment is applicable to either method. The multi-voxel method is also called chemical shift imaging (CSI), MRS imaging (MRSI), etc. Note that the voxels in the measurement target area are also called voxels of interest (VOI). Furthermore, in this embodiment, a two-dimensional region specified by MRSI and voxels of interest are also referred to as a region of interest.

The sequence control circuit 29 executes data collection for MRS on the subject P. By performing data acquisition for MRS, a free induction decay (FID) signal or a spin echo signal is generated from the voxel of interest of the subject P. The receiving circuit 25 receives the FID signal or spin echo signal via the receiving coil 47, processes the received FID signal or spin echo signal, and collects k-space data regarding the voxel of interest. It is assumed that the collected k-space data is digital data representing signal intensity values emitted from the voxel of interest as a function of time. The pulse sequence for MRS is repeated for the number of excitations (NEX), and k-space data is collected for the number of excitations. Hereinafter, the k-space data collected by MRS will be referred to as MRSk data. MRSk data is an example of an MRS signal.

As the MRS pulse sequence, for example, PRESS (point resolved spectroscopy), STEAM (stimulated echo acquisition mode), semi-LASER (semi-localization by adiabatic selective refocusing), or LASER may be used; However, any pulse sequence that can collect MRS signals may be used.

As shown in FIG. 1, the medical data processing device 50 is a computer having a processing circuit 51, a memory 53, a display 55, an input interface 57, and a communication interface 59.

The processing circuit 51 has a processor such as a CPU as a hardware resource. The processing circuit 51 functions as the core of the magnetic resonance imaging apparatus 1 . For example, the processing circuit 51 implements a setting function 511, a determination function 512, a learning function 513, and a display control function 514 by executing various programs.

Using the setting function 511, the processing circuit 51 sets an expanded region of interest that includes the region of interest and the area around the region of interest.
Using the determination function 512, the processing circuit 51 determines an OVS (Outer Volume Suppression) pattern for suppressing a signal to be applied to a region outside the expanded region of interest.
Using the learning function 513, the processing circuit 51 learns a network model and generates a learned model based on previously acquired MRS signals and medical data including acquisition conditions.
Using the display control function 514, the processing circuit 51 displays the set enlarged region of interest and the determined OVS pattern on the display 55 or the like.

The memory 53 is a storage device such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or an integrated circuit storage device that stores various information. Further, the memory 53 may be a drive device or the like that reads and writes various information to/from a portable storage medium such as a CD-ROM drive, a DVD drive, or a flash memory. For example, the memory 53 stores medical data collected in the past, learned models, MRS signals, control programs, and the like.

The display 55 displays various information from the display control function 514. As the display 55, for example, a CRT display, a liquid crystal display, an organic EL display, an LED display, a plasma display, or any other display known in the art can be used as appropriate.

The input interface 57 includes input devices that accept various commands from the user. As input devices, keyboards, mice, various switches, touch screens, touch pads, etc. can be used. Note that the input device is not limited to those equipped with physical operation parts such as a mouse and a keyboard. For example, an electrical signal processing circuit that receives electrical signals corresponding to input operations from an external input device provided separately from the magnetic resonance imaging apparatus 1 and outputs the received electrical signals to various circuits is also input. Included in the example of interface 57. The input interface 57 may also be a voice recognition device that converts voice signals collected by a microphone into instruction signals.

The communication interface 59 connects the magnetic resonance imaging apparatus 1 to a workstation, a PACS (Picture Archiving and Communication System), an HIS (Hospital Information System), an RIS (Radiology Information System), etc. via a LAN (Local Area Network) or the like. This is the interface to connect. The communication interface 59 transmits and receives various information to and from connected workstations, PACS, HIS, and RIS.

Next, an example of the operation of the magnetic resonance imaging apparatus 1 including the medical data processing apparatus 50 according to this embodiment will be described with reference to the flowchart of FIG. 2.

In step SA1, the processing circuit 51 uses the setting function 511 to set a region of interest for the region to be imaged. For example, the voxels serving as the measurement target area may be set by user input. Further, the processing circuit 51 may automatically set the region of interest depending on the region to be imaged, the case, and the like.

In step SA2, the processing circuit 51 uses the setting function 511 to set an expanded region of interest that includes the region of interest set in step SA1. As a method for setting the enlarged region of interest, for example, a region specified by the user via the input interface 57 may be set as the enlarged region of interest, or an enlarged region of interest may be estimated from the region of interest using a trained model. Good too. Details of the trained model will be described later with reference to FIG. 7.

In step SA3, the processing circuit 51 uses the determination function 512 to determine an OVS pattern for the signal suppression region, which is the region in which the signal is desired to be suppressed, in accordance with the enlarged region of interest. The OVS pattern may be realized by combining a plurality of unit areas, or may be realized in a complex shape such as a cylindrical shape or a polygon (polygonal prism), which can be expressed by a two-dimensional or more slice profile. .

In step SA4, the processing circuit 51 uses the determination function 512 to determine the position and number of OVS patterns to be applied, and the pre-pulse (hereinafter referred to as OVS pulse), such as a suppression pulse, which suppresses the signal for a plurality of unit areas as the OVS pattern. ) is applied. Specifically, when the OVS pattern is realized by combining a plurality of unit areas, the number and position of the unit areas and the application order of the plurality of OVS pulses are determined. The number of unit regions is determined from the number of OVS pulses that can be applied, for example, depending on the length of TR (Repetition time) of the MRS pulse sequence. The positions of the unit regions may be determined so that the enlarged region of interest 32 is surrounded by the determined number of unit regions. The order in which the OVS pulses are applied may be determined such that the greater the influence of the signal on the expanded region of interest is, the later the order in which the OVS pulses are applied to the region.

In step SA5, for example, the sequence control circuit 29 executes imaging according to the imaging sequence of the MRS pulse sequence based on the position and number of unit areas and the application order of OVS pulses determined in step SA4. Specifically, the MRS pulse sequence is repeatedly executed and MRS signals are collected. The number of times the MRS pulse sequence is repeated is determined, for example, based on the number of times the MRS signal is integrated.

Next, an example of the enlarged region of interest according to this embodiment will be described with reference to FIG. 3.
FIG. 3 is an example in which an enlarged region of interest 32 is set on an MR image 31 that is an axial section of the head. Specifically, when the region of interest 33 is set, the processing circuit 51 uses the setting function 511 to set the expanded region of interest 32 including the peripheral region of the region of interest 33. One criterion for determining the extent of the region to be included as the expanded region of interest 32 is that it is an allowable region that does not generate unnecessary signals such as fat when measuring signals of the region of interest. Further, the processing circuit 51 may set the enlarged region of interest 32 using the setting function 511 so that the region of the region of interest 33 where the signal is suppressed is less than a threshold value.

In the example of FIG. 3, the expanded region of interest 32 is formed by two values, the region of interest 33 and the area around the region of interest 33 that forms the expanded region of interest 32, but the setting function 511 allows the processing circuit to 51 may set reliability for each pixel of the expanded region of interest. In other words, the region of interest 33 and the surrounding region of one pixel from the outer edge of the region of interest have a reliability of "80%", and the surrounding region of one pixel from the outer edge with the reliability of "80%" has a reliability of "50%". A multi-stage enlarged region of interest 32 may be set such that the reliability decreases from the region of interest 33 toward the outer edge.
In this case, unit regions may be determined to overlap with each other in regions of the enlarged region of interest 32 whose reliability is less than or equal to a threshold value. That is, the signal may be suppressed by the OVS pattern in a region where the reliability is less than or equal to the threshold value.

Next, a first example of an OVS pattern set for the enlarged region of interest in FIG. 3 will be described with reference to FIG. 4.
The OVS pattern shown in FIG. 4 is an example of an OVS pattern for the enlarged region of interest 32 shown in FIG. It is. Specifically, by applying the OVS pulse to each of the three unit regions, signals from the region where the unit regions are arranged are suppressed. By applying an OVS pulse while applying a gradient magnetic field in a direction oblique to the direction of the gradient magnetic field (oblique), the unit regions 401 to 403 are aligned parallel to or perpendicular to each axis (x-axis, y-axis, and z-axis). The unit area is not limited to being formed at a desired angle, and the unit area can be freely set at a desired angle so as to surround the enlarged region of interest 32. Note that although the unit areas 401 to 403 are rectangular in the example shown, they are not limited to this, and may have any template shape such as a polygon or a circle.

As described above, the determining function 512 causes the processing circuit 51 to determine the application order of OVS pulses to be applied to a region outside the expanded region of interest 32 as the degree of influence of the signal on the expanded region of interest 32 is greater. The sequence of OVS pulses is designed so that the
This is because when a second OVS pulse is applied next after applying a first OVS pulse corresponding to a certain unit area, the influence on the first OVS pulse cannot be easily estimated. Therefore, it is thought that the desired signal suppression effect can be obtained by applying the OVS pulse corresponding to the unit region that is most desired to be suppressed as the last of the plurality of OVS pulses. A region with a large degree of influence is, for example, a region with a large area or a region in which a large amount of fat exists, and refers to a region where unnecessary signals are likely to be generated. Such a region having a large degree of influence may be determined, for example, from empirical data, or may be determined from an MR image captured before collecting MRS signals.
In FIG. 4, the OVS pulse is applied in the order of unit area 401, unit area 402, and unit area 403. That is, in the example of FIG. 4, it can be said that more unnecessary signals are generated in the order of unit area 403, unit area 402, and unit area 401.

Next, an MRS pulse sequence including an OVS pulse will be explained with reference to FIG.
FIG. 5 is a schematic diagram of a chronological MRS pulse sequence for applying the OVS pattern shown in FIG. 4. Here, only the RF axis is shown to explain the applied pulses, and the explanation of the application timing of the gradient magnetic field is omitted. However, at the timing when the OVS pulse and RF pulse are applied, the gradient magnetic field along the MRS pulse sequence is shall be applied.

The OVS pulse 501 is a pulse for applying the unit area 401 shown in FIG. 4, the OVS pulse 502 is a pulse for applying the unit area 402, and the OVS pulse 503 is a pulse for applying the unit area 403. be.
Among the unit regions that realize the OVS pattern, the OVS pulse is applied to the unit regions in order of decreasing influence on the signal of the enlarged region of interest 32. That is, OVS pulse 501, OVS pulse 502, and OVS pulse 3 are applied in this order.

In this way, after OVS pulses 501-503 are applied as pre-pulses, RF pulse 504 is applied to the enlarged region of interest. Thereafter, although not shown, an inversion pulse or the like may be applied and the MRS signal 505 generated as an echo may be measured.
Next, a second example of the OVS pattern set for the enlarged region of interest in FIG. 3 will be described with reference to FIG. 6.

In the second example shown in FIG. 6, an O-shaped OVS pattern 61 that surrounds the enlarged region of interest 32 shown in FIG. 3 is shown. In this way, the OVS pattern is not limited to a combination of a plurality of unit areas as shown in FIG. 4, but may have a complicated shape.
In order to realize such an OVS pattern, for example, the memory 53 stores a candidate set of OVS patterns based on slice profiles of two or more dimensions. The determining function 512 allows the processing circuit 51 to select, from among the stored candidate sets, candidates that can appropriately suppress signal suppression regions that generate unnecessary signals for the enlarged region of interest.

Note that although FIGS. 4 and 6 illustrate OVS patterns in a two-dimensional plane in an axial section, the OVS patterns may be applied in a three-dimensional space. For example, in FIG. 4, the unit areas 401 to 403 are rectangular parallelepipeds extending in the direction perpendicular to the page, and the unit areas may be set on a plane perpendicular to the direction perpendicular to the page. In the example of FIG. 6, the OVS pattern 61 has a hollow cylindrical shape, and furthermore, the unit area may be set on a plane perpendicular to the direction perpendicular to the paper surface.
Further, for example, a composite region may be set in which a unit region corresponding to a thickness of 3 cm and a unit region corresponding to a thickness of 5 cm are combined at a specific gradient magnetic field strength. By designing an OVS pulse corresponding to the combined region, the time of the pulse sequence can be made shorter than, for example, when applying the OVS pulse to a plurality of unit regions individually.

Next, an example of generating a trained model for estimating an expanded region of interest from a region of interest will be described with reference to FIG.
FIG. 7 is an example of a learning process for a network model before learning.
Using the learning function 513, the processing circuit 51 learns MR images such as positioning images and T2-weighted images, the region of interest set in the MR images, and the setting status of the OVS pattern from medical data related to past MRS signal collection cases. The network model 71 is trained using the input data as input data and the region including the region of interest surrounded by the OVS pattern as correct data of the expanded region of interest.

Regarding the network structure and learning method of the network model 71, for example, a method such as minimizing a loss function by error backpropagation using a neural network or a convolutional neural network may be used, but machine learning is not limited to this. Any commonly used learning method may be used. When the learning is completed by satisfying a predetermined termination condition, for example, when the loss function becomes equal to or less than a threshold value, the learning is completed and a trained model 72 is generated.

When inferring a trained model, the processing circuit 51 uses the setting function 511 to input an MR image and a region of interest set for the MR image to the generated trained model 72, and As the inference result in step 72, an expanded region of interest is output.
Note that the above example shows an example in which an expanded region of interest is flexibly set and an OVS pattern is adaptively designed for the expanded region of interest. It's okay.

FIG. 8 shows an example in which the region of interest is set to a desired region shape.
FIG. 8 shows a region of interest 81 excited in a non-rectangular shape, not a square but a triangle when viewed on a two-dimensional plane. Specifically, the sequence control circuit 29 uses two-dimensional or three-dimensional excitation pulses to apply a plurality of excitation pulses, refocus pulses, and a gradient magnetic field while changing in time series, thereby forming a non-rectangular shape. The region of interest 81 can be excited.
Using the setting function 511, the processing circuit 51 sets a region of interest that can be represented by two-dimensional or three-dimensional excitation pulses and refocus pulses. Using the determination function 512, the processing circuit 51 may determine the amplitude, phase, flip angle, excitation position, and application order of the excitation pulse and refocus pulse for imaging the set expressible region of interest.

According to the present embodiment described above, an expanded region of interest that includes a region of interest that is a measurement target region and a region around the region of interest is set, and a method for suppressing signals in areas outside the expanded region of interest is set. By determining the OVS pattern, unnecessary signals can be appropriately suppressed in areas other than rectangular areas. Further, by applying the OVS pattern, the signal strength of the MRS signal collected from the region of interest can be relatively strengthened.

Note that the term "processor" used in the above description refers to, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an Application Specific Integrated Circuit (ASIC), a programmable logic device ( For example, it refers to circuits such as a Simple Programmable Logic Device (SPLD), a Complex Programmable Logic Device (CPLD), and a Field Programmable Gate Array (FPGA). When the processor is, for example, a CPU, the processor realizes its functions by reading and executing a program stored in a storage circuit. On the other hand, when the processor is, for example, an ASIC, instead of storing the program in a storage circuit, the function is directly incorporated into the processor's circuitry as a logic circuit. Note that each processor of this embodiment is not limited to being configured as a single circuit for each processor, but may also be configured as a single processor by combining multiple independent circuits to realize its functions. good. Furthermore, multiple components in the figures may be integrated into one processor to implement its functions.

In addition, each function according to the embodiment can also be realized by installing a program that executes the above-mentioned processing on a computer such as a workstation and expanding it on memory. At this time, a program that can cause a computer to execute the above method can be stored and distributed in a storage medium such as a magnetic disk (hard disk, etc.), optical disk (CD-ROM, DVD, etc.), semiconductor memory, etc. .

Although several embodiments have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, changes, and combinations of embodiments can be made without departing from the gist of the invention. These embodiments and their modifications are included within the scope and gist of the invention as well as within the scope of the invention described in the claims and its equivalents.

Regarding the above embodiments, the following additional notes are disclosed as one aspect and optional features of the invention.

(Additional note 1)
a setting unit that sets an expanded region of interest including a region of interest and a region around the region of interest;
a determining unit that determines an OVS (Outer Volume Suppression) pattern for suppressing a signal to be applied to a region outside the expanded region of interest;
A medical data processing device comprising:

(Additional note 2)
The OVS pattern may be realized by combining a plurality of unit areas,
The determining unit may determine the number and position of the unit regions to be applied to a region outside the expanded region of interest, and the application order of OVS pulses for suppressing signals to the unit regions.

(Additional note 3)
The OVS pattern may be realized by combining a plurality of unit areas,
The determining unit may determine that the larger the degree of influence of the signal on the expanded region of interest is, the later the application order of OVS pulses applied to the unit region is.

(Additional note 4)
Each of the plurality of unit areas may have a predetermined template shape.

(Appendix 5)
The OVS pattern may have a shape that can be expressed by a two-dimensional or more slice profile.

(Appendix 6)
The OVS pattern may be realized by combining a plurality of unit areas,
The determining unit may determine a composite area that is a composite of two or more unit areas from among the plurality of unit areas.

(Appendix 7)
The setting unit may set the expanded region of interest so that a region of the region of interest in which a signal is suppressed is less than a threshold.

(Appendix 8)
The setting unit may set reliability for each pixel of the expanded region of interest.

(Appendix 9)
The design department uses as input data a magnetic resonance image taken in the past, a first region of interest set in the magnetic resonance image, and an application status of the OVS to the first region of interest, and generates a signal using the OVS. A second region of interest for a new imaging target is input to the learned model using a trained model that has learned the area around the first region of interest in which the region of interest has not been suppressed and the first region of interest as correct data. In this way, an expanded region of interest regarding the second region of interest may be estimated.

(Appendix 10)
a setting unit that sets a region of interest that can be represented by a two-dimensional or three-dimensional excitation pulse and a refocusing pulse;
a determining unit that determines the amplitude, phase, flip angle, excitation position, and application order of an excitation pulse and a refocusing pulse for imaging the region of interest;
A medical data processing device comprising:

(Appendix 11)
setting an expanded region of interest including a region of interest and a region around the region of interest;
A medical data processing method that determines an OVS (Outer Volume Suppression) pattern for suppressing a signal to be applied to a region outside the expanded region of interest.

(Appendix 12)
to the computer,
a setting function for setting an expanded region of interest including a region of interest and a region around the region of interest;
a determination function that determines an OVS (Outer Volume Suppression) pattern for suppressing a signal to be applied to a region outside the expanded region of interest;
A medical data processing program that realizes.

(Appendix 13)
a setting unit that sets an expanded region of interest including a region of interest and a region around the region of interest;
a determining unit that determines an OVS (Outer Volume Suppression) pattern for suppressing a signal to be applied to a region outside the expanded region of interest;
an acquisition unit that collects an MRS signal corresponding to an MRS pulse sequence from the expanded region of interest after applying a signal suppression pulse along the OVS pattern;
A magnetic resonance imaging device comprising:

1 Magnetic Resonance Imaging Apparatus 11 Mount 13 Bed 21 Gradient Magnetic Field Power Supply 23 Transmission Circuit 25 Receiving Circuit 27 Bed Drive Device 29 Sequence Control Circuit 31 MR Image 32 Expanded Region of Interest 33,81 Region of Interest 41 Static Magnetic Field Magnet 43 Gradient Magnetic Field Coil 45 Transmission Coil 47 Receiving coil 50 Medical data processing device 51 Processing circuit 53 Memory 55 Display 57 Input interface 59 Communication interface 61 OVS pattern 71 Network model 72 Learned model 131 Top plate 133 Base 401-403 Unit area 501-503 OVS pulse 504 RF pulse 505 MRS signal 511 Setting function 512 Determination function 513 Learning function 514 Display control function

Claims (13)

a setting unit that sets an expanded region of interest including a region of interest and a region around the region of interest;
a determining unit that determines an OVS (Outer Volume Suppression) pattern for suppressing a signal to be applied to a region outside the expanded region of interest;
A medical data processing device comprising: The OVS pattern is realized by combining a plurality of unit areas,
2. The determination unit according to claim 1, wherein the determining unit determines the number and position of the unit regions to be applied to a region outside the expanded region of interest, and the application order of OVS pulses for suppressing signals to the unit regions. The medical data processing device described. The OVS pattern is realized by combining a plurality of unit areas,
2. The medical data processing apparatus according to claim 1, wherein the determination unit applies the OVS pulses to a region having a larger influence on the expanded region of interest, the later the OVS pulse is applied to the unit region. The medical data processing apparatus according to claim 2, wherein each of the plurality of unit areas is an area having a predetermined template shape. The medical data processing apparatus according to claim 1, wherein the OVS pattern has a shape that can be expressed by a two-dimensional or more slice profile. The OVS pattern is realized by combining a plurality of unit areas,
The medical data processing apparatus according to claim 1, wherein the determining unit determines a composite region that is a composite of two or more unit regions among the plurality of unit regions. The medical data processing apparatus according to claim 1, wherein the setting unit sets the expanded region of interest so that a region in which a signal is suppressed in the region of interest is less than a threshold value. The medical data processing apparatus according to claim 1, wherein the setting unit sets reliability for each pixel of the expanded region of interest. The design department uses as input data a magnetic resonance image taken in the past, a first region of interest set in the magnetic resonance image, and an application status of the OVS to the first region of interest, and generates a signal using the OVS. A second region of interest for a new imaging target is input to the learned model using a trained model that has learned the area around the first region of interest in which the region of interest has not been suppressed and the first region of interest as correct data. The medical data processing apparatus according to claim 1, wherein an expanded region of interest regarding the second region of interest is estimated by doing so. a setting unit that sets a region of interest that can be represented by a two-dimensional or three-dimensional excitation pulse and a refocusing pulse;
a determining unit that determines the amplitude, phase, flip angle, excitation position, and application order of an excitation pulse and a refocusing pulse for imaging the region of interest;
A medical data processing device comprising: setting an expanded region of interest including a region of interest and a region around the region of interest;
A medical data processing method that determines an OVS (Outer Volume Suppression) pattern for suppressing a signal to be applied to a region outside the expanded region of interest. to the computer,
a setting function for setting an expanded region of interest including a region of interest and a region around the region of interest;
a determination function that determines an OVS (Outer Volume Suppression) pattern for suppressing a signal to be applied to a region outside the expanded region of interest;
A medical data processing program that realizes. a setting unit that sets an expanded region of interest including a region of interest and a region around the region of interest;
a determining unit that determines an OVS (Outer Volume Suppression) pattern for suppressing a signal to be applied to a region outside the expanded region of interest;
an acquisition unit that collects an MRS signal corresponding to an MRS pulse sequence from the expanded region of interest after applying a signal suppression pulse along the OVS pattern;
A magnetic resonance imaging device comprising: