KR20220040977A - Apparatus for generating Field Free, Apparatus and Method for Nano Magnetic Particle Image - Google Patents

Abstract

An embodiment discloses a nanomagnetic particle imaging device using a three-dimensional small magnet array. A field-free generating device according to the embodiment may install a pair of square magnets wherein a hexahedral housing having an opening formed on one side surface thereof is formed so that a measuring head is inserted into a separation part, and each installed on two opposite side surfaces among four side surfaces perpendicular to one side surface in the housing; and a pair of magnet arrays wherein a plurality of small magnets are arranged at the edge of the opening each on one side surface of the housing and the other side surface facing the one side surface. Therefore, the present invention is capable of increasing a degree of freedom in the movement of a sample.

Description

Apparatus for generating Field Free, Apparatus and Method for Nano Magnetic Particle Image

The described embodiment relates to an imaging technique for a specific object included in a sample, and more particularly, to a technique for imaging the spatial distribution of a nano-magnetic particle (NMP) material.

Magnetic particle imaging (MPI) using superparamagnetic iron oxide nano particles (SPIOs) is a medical imaging equipment technology that replaces PET (Positron Emission Tomography). This is an ongoing next-generation medical imaging technique.

This is a field free point (FFP) or field free line (Field Free Point), which is a field-free area where the magnetic field strength is close to 0 (zero) at points, lines, and planes in space in order to make MPI equipment that can be expanded into three-dimensional space. You need to create a Free Line (FFP). Here, the sharper the steepness of the magnetic field in the FFP or FFL, the better the resolution, so creating such a region in space is a key technique in MPI.

However, the method proposed so far, like all other electromagnetic field generation methods, can be largely divided into two types: a method using an electromagnet and a method using a permanent magnet.

Among them, the method using the electromagnet can control the position of the electromagnetic field with the strength of the current and the position of the coil. However, although the electromagnet-based MPI equipment that has been commercialized or manufactured for research so far consumes power up to several tens to hundreds of kilowatts, it has a disadvantage in that it is impossible to measure except for relatively very small samples such as mice for experiments.

On the other hand, the method using a permanent magnet has no choice but to use a large magnet to generate the FFL or FFP, despite the advantages of little power consumption and downsizing of equipment. Such a large magnet is difficult to manufacture, and the strength of the surface magnetic force is not uniform, and there is a risk of a large safety accident due to the strong magnetic force, and there is a possibility that many accidents may actually occur.

According to the embodiment, the field-free region in the MPI using a permanent magnet is created using an arrangement of small magnets, not a large magnet, and a medium-sized square magnet, thereby overcoming the disadvantages of the large magnet.

In the field-free generating device according to the embodiment, a hexahedral housing having an opening formed on one side thereof is formed so that the measuring head is inserted into the spaced area, and on each of the two opposite sides of the four sides perpendicular to one side of the housing. A pair of installed square magnets and a pair of magnet arrays in which a plurality of small magnets are arranged at the edge of the opening on one side of the housing and the other side facing the one side may be installed.

In this case, the plurality of small magnets may be arranged in a circle at the edge of the opening.

In this case, the field free area may be a field free point (FFP) or a field free line (FFL).

The field-free generating apparatus according to the embodiment may further include a first driving unit that linearly moves or rotates the pair of square magnets.

In the magnetic nanoparticle imaging apparatus according to the embodiment, a through hole in which a sample containing the magnetic nanoparticle is accommodated is formed, a measurement head in which an excitation coil and a detection coil are installed, and a magnetic field in a spaced region between the same facing magnetic poles As the field-free generator and the measuring head that form the field-free region are positioned within the spaced region of the field-free generator, a signal is applied to the excitation coil, and the field-free region is controlled to move within the sample, which is output from the detection coil. A control unit for imaging the three-dimensional position distribution of the nano magnetic particles included in the sample based on the detection signal, wherein the field-free generation unit generates a pair of magnet arrays in which a pair of square magnets and a plurality of small magnets are arranged may include

In this case, the field-free generator includes a hexahedral housing having an opening formed on one side so that the measuring head is inserted into the spaced area, and a pair of Square magnets are installed, and a pair of magnet arrays in which a plurality of small magnets are arranged at the edge of the opening may be installed on one side of the housing and the other side facing one side, respectively.

In this case, the plurality of small magnets may be arranged in a circle at the edge of the opening.

In this case, the field free area may be a field free point (FFP) or a field free line (FFL).

At this time, the controller generates a two-dimensional image that is a two-dimensional position distribution of the magnetic nanoparticles included in the cross-section of the sample based on the detection signal, and synthesizes a plurality of two-dimensional images corresponding to a plurality of cross-sections that are horizontal to each other. A 3D image can be created.

The magnetic nanoparticle imaging apparatus according to the embodiment may further include a first driving unit for linearly moving or rotating the pair of square magnets.

At this time, the control unit controls the first driving unit to repeatedly perform linear movement in one direction and rotation in one direction and a predetermined angle of the pair of square magnets, so that the signal output from the detection signal according to the movement of the field-free area is converted into a cyno A gram may be generated, and the generated sinogram may be inversely radon-transformed to generate a two-dimensional image.

The magnetic nanoparticle imaging apparatus according to the embodiment may further include a second driving unit for moving the measuring head to the spaced area through the opening of the field-free generating unit.

In this case, the controller may repeat the generation of the two-dimensional image while moving the measuring head by a predetermined unit length in a direction perpendicular to the cross-section of the sample.

The magnetic nanoparticle imaging method according to the embodiment includes the steps of applying a signal to an excitation coil installed in a measurement head that accommodates a sample containing nanomagnetic particles, and a field in which a magnetic field generated within a spaced region between the same magnetic poles facing each other is sparse. moving the free area in the sample to image the three-dimensional position distribution of the magnetic nanoparticles included in the sample based on the detection signal output from the detection coil of the measuring head, wherein the field free area includes a pair of Square magnets and a plurality of small magnets may be created by a pair of arranged magnet arrays.

At this time, the pair of square magnets are installed on each of the two opposing sides of the four sides perpendicular to one side in the housing of a hexahedron having an opening formed on one side so that the measuring head is inserted into the spaced area, and the pair of In the magnet arrays, a plurality of small magnets may be arranged at the edge of the opening on one side of the housing and the other side opposite to the one side, respectively.

In this case, the plurality of small magnets may be arranged in a circle at the edge of the opening.

In this case, the field free area may be a field free point (FFP) or a field free line (FFL).

In this case, the imaging of the three-dimensional position distribution includes generating a two-dimensional image that is a two-dimensional position distribution of the nanomagnetic particles included in the cross-section of the sample based on the detection signal and corresponding to a plurality of cross-sections that are horizontal to each other. The method may include generating a 3D image by synthesizing a plurality of 2D images.

In this case, the step of generating the two-dimensional image includes moving a pair of square magnets linearly in one direction or rotating to have a predetermined angle with one direction, while moving between the detection signal and the output signal according to the movement of the field-free area. A two-dimensional image may be generated by generating a nogram and performing inverse radon transformation on the generated sinogram.

In this case, the generating of the two-dimensional image may be repeated while moving the measuring head by a predetermined unit length in a direction perpendicular to the cross-section of the sample.

According to the embodiment, the degree of freedom in spatial configuration using small magnets is increased, so that it is easy to place the sample in the field-free area. That is, a large pair of permanent magnets or a pair of coils has been conventionally used to create a field-free region. However, in the case of a rectangular permanent magnet, it was difficult to secure an area for inserting the sample when trying to position the sample near the field-free area. The field-free generator according to the embodiment may provide a window of a predetermined size to the sample insertion unit to increase the degree of freedom in movement of the sample.

According to the embodiment, the size of the magnet is reduced to reduce the deviation of the magnetic field strength. That is, conventionally, when a large magnet is used to generate a field-free region, it has been difficult to secure a magnet having a uniform magnetic field strength. This is because as the size of the magnet increases, it becomes significantly more difficult to make a magnet having a uniform magnetic field strength. The field-free generating device based on a Halbach array magnet consisting of an arrangement of small magnets according to an embodiment makes it easy to secure a magnet that generates a uniform magnetic field.

According to an embodiment, a stronger field-free magnetic field gradient may be generated with less weight compared to a large-area magnet. That is, in MPI technology, the resolution is proportional to the field-free magnetic field gradient. In MPI technology, in order to obtain a high field-free area as the FOV increases, it is necessary to use a very large magnet or apply a very high current to the coil to generate a field-free area. When a field-free generating device based on a Halbach array magnet consisting of an arrangement of small magnets according to the embodiment is used, it is possible to generate a field-free region that is relatively light and strong at a level required for preclinical research.

According to an embodiment, the field free region may be formed without expensive power supply or unnecessary heat generation. That is, when a coil pair is used to create a field-free region in the prior art, very high power is typically required to form a magnetic field strong enough to correspond to a permanent magnet. Therefore, an expensive power supply is required, and considerable heat is generated in the coil. According to an embodiment, forming a field-free region with a combination of small magnets may reduce power supply cost and heat generation.

According to an embodiment, through the arrangement of small magnets, higher resolution MPI equipment may be manufactured lighter, smaller, and cheaper. That is, when the size of the magnet exceeds 50mm x 50mm, it is difficult to obtain a commercial magnet (a magnet that can be purchased directly through a magnet wholesaler and retailer), and it is difficult to obtain a commercial magnet by requesting it from a magnet manufacturing factory. When the cost explodes from several times to several tens of times.

1 is a schematic block diagram of a magnetic nanoparticle imaging apparatus according to an embodiment.
2 is an exemplary diagram of a structure of a nanomagnetic particle imaging apparatus according to an embodiment.
3 is an exemplary view of one side of the housing of the field-free generator according to the embodiment.
4 is a layout diagram of a square magnet and a small magnet array of a field-free generator according to an embodiment.
5 is a diagram illustrating a magnetic field direction according to the arrangement of the square magnet and the small magnet array of the field-free generator according to the embodiment.
6 is an exemplary view illustrating field-free generation according to the arrangement of a square magnet and a small magnet array of a field-free generation unit according to an embodiment.
7 is a flowchart for explaining a method for imaging nanomagnetic particles according to an embodiment.
8 to 12 are diagrams illustrating movement of a field-free line as a pair of square magnets move in one direction according to an embodiment.
13 to 22 are diagrams illustrating rotation of a field-free line as a pair of square magnets rotate according to an embodiment.
23 to 26 are diagrams illustrating performance of a small MPI scanner to which a field-free generator is applied according to an embodiment.
27 to 30 are diagrams illustrating the structure of a brain MPI scanner to which a field-free generator is applied according to an embodiment.
31 is a diagram showing the configuration of a computer system according to an embodiment.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

Although "first" or "second" is used to describe various elements, these elements are not limited by the above terms. Such terms may only be used to distinguish one component from another. Accordingly, the first component mentioned below may be the second component within the spirit of the present invention.

The terminology used herein is for the purpose of describing the embodiment and is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, “comprises” or “comprising” implies that the stated component or step does not exclude the presence or addition of one or more other components or steps.

Unless otherwise defined, all terms used herein may be interpreted with meanings commonly understood by those of ordinary skill in the art to which the present invention pertains. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless specifically defined explicitly.

Hereinafter, a field-free generating apparatus, a nanomagnetic particle imaging apparatus, and a method according to an embodiment will be described in detail with reference to FIGS. 1 to 19 .

1 is a schematic block diagram of an apparatus for imaging nanomagnetic particles according to an embodiment, and FIG. 2 is an exemplary diagram of a structure of an apparatus for imaging nanomagnetic particles according to an embodiment.

Referring to FIG. 1 , an apparatus 1 for imaging nanomagnetic particles according to an embodiment includes a measurement head 110 , a field-free generator 120 , a controller 130 , a first driver 140 , and a second driver 150 . ) may be included.

The measurement head 110 has a through hole in which a sample containing magnetic nanoparticles is accommodated, and an excitation coil 111 and a detection coil 112 are installed. At this time, the excitation coil 111 generates a magnetic field in the measurement head 110 in which the sample containing the magnetic nano particles is inserted. In this case, the detection coil 112 may acquire a detection signal from the sample existing inside the through hole of the measurement head 110 .

The field-free generator 120 forms a field-free region in which a magnetic field is thin in a spaced region between the same magnetic poles facing each other.

Here, the basic principle of signal acquisition in Magnetic Particle Imaging (MPI) is a harmonic due to the nonlinear magnetic properties of a Nano Magnetic Particle (NMP) in a gradient magnetic field. It is signal based. At this time, the two identical magnetic poles are made to face each other so that the nonlinear magnetization phenomenon does not occur and is saturated (saturation), thereby creating a region in which a magnetic field is sparse in a predetermined region of the spaced apart region. In more detail, imaging is performed using a spatial location where a harmonic signal is generated by moving the field-free region in space.

In this case, the field free area may be a field free point (FFP) or a field free line (FFL).

According to an embodiment, the field-free generator 120 may include a pair of magnet arrays in which a pair of square magnets and a plurality of small magnets are arranged to form an FFL having a high magnetic inclination.

That is, as described above, the embodiment generates an FFL based on a permanent magnet in order to solve the problems of power consumption and equipment design, which are problems in the conventional magnetic magnetic imaging system, but in this case, the permanent magnet is used in a Hallbach array It is characterized by replacing it with an array). Here, in the Hallbach array, a plurality of small magnets are arranged in a predetermined array form, and the strength and direction of a magnetic field can be adjusted.

The controller 130 controls the entire process of imaging the magnetic nanoparticles by controlling the components. Here, the controller 130 may include all kinds of devices capable of processing data, such as a processor. Here, the 'processor' may refer to a data processing device embedded in hardware having a physically structured circuit to perform a function expressed as, for example, a code or an instruction included in a program.

According to an embodiment, the controller 130 applies a signal to the excitation coil 111 as the measurement head 110 is positioned within the penetration region of the field-free generator 120 , and the field-free region moves within the sample. By controlling so as to be, the three-dimensional position distribution of the magnetic nanoparticles included in the sample may be imaged based on the detection signal output from the detection coil 112 . According to an embodiment, the controller 130 controls the FFP or FFL to continuously move, aligning and displaying the detection signals detected while the sample overlaps the FFP or FFL, thereby obtaining 3D image information corresponding to the magnetic nanoparticle. can do. For example, the three-dimensional image information may include three-dimensional image information in the form of a contour plot.

In this case, the controller 130 generates a two-dimensional image that is a two-dimensional position distribution of the nano-magnetic particles included in the cross-section of the sample based on the detection signal, and generates a plurality of two-dimensional images corresponding to a plurality of cross-sections that are horizontal to each other. By synthesizing them, a 3D image can be generated. In this case, the cross section of the sample may be parallel to the XY plane shown in FIG. 2 .

At this time, the controller 130 linearly moves the field-free area in one direction in the cross section of the sample, and then linearly moves the field-free area in one direction and another direction having a predetermined unit angle, and detects according to the movement of the field-free area. A sinogram may be generated with a signal output from the signal, and the generated sinogram may be subjected to inverse Radon transformation to generate a two-dimensional image.

In this case, a sinogram is a sequential arrangement of projection data acquired in one direction along the projection direction, and pixel values of each row are equal to the amplitude at the corresponding position of the corresponding profile. Such a sinogram (Sinogram) is a well-known technique and detailed description thereof will be omitted. In addition, the inverse radon transform is a two-dimensional image generation technique using sinograms widely used in CT, etc. "Kak, AC, and M. Slaney, Principles of Computerized Tomographic Imaging, New York, NY, IEEE Press , 1988", since it is a known technique, a detailed description thereof will be omitted.

For example, referring to FIG. 2 , the field-free area may be rotated by a predetermined unit angle in the XY plane or may be linearly moved in a rotated state. This may be referred to as a T-ROUND STAGE movement.

Accordingly, the magnetic nanoparticle imaging apparatus 1 according to the embodiment includes the first driving unit 140 for rotating or linearly moving the field-free generating unit 120 .

Also, the controller 130 may repeat the 2D image generation while moving the measuring head 110 by a predetermined unit length in a direction perpendicular to the cross-section of the sample. That is, as the measurement head 110 is linearly moved in the Z-axis direction, two-dimensional images of each of the cross-sections through which the field-free area passes may be obtained.

To this end, the magnetic nanoparticle imaging apparatus 1 according to the embodiment may include a second driving unit 150 that moves the measurement head 110 to a spaced region of the field-free generator 120 .

Next, the field-free generator 120 according to the embodiment will be described in detail.

3 is an exemplary view of a housing of the field-free generator according to the embodiment, FIG. 4 is a layout view of a square magnet and a small magnet array of the field-free generator according to the embodiment, and FIG. 5 is a square magnet of the field-free generator according to the embodiment. And it is an exemplary view of the magnetic field direction according to the arrangement of the small magnet array, FIG. 6 is an exemplary view of the field-free generation according to the arrangement of the square magnet and the small magnet array of the field-free generating unit according to the embodiment.

Referring to FIG. 3 , the field-free generator 120 includes a hexahedral housing in which an opening 123 is formed on one side so that the measuring head is inserted into the spaced region.

A pair of square magnets 121a and 121b are installed on two opposite sides of the four sides perpendicular to one side of the housing, respectively, and a plurality of square magnets are installed on one side of the housing and the other side facing the one side, respectively. A pair of magnet arrays 122a in which small magnets are arranged at the edge of the opening may be installed.

According to an embodiment, as shown in FIG. 4 , the plurality of small magnets 122a and 122b may be arranged in a ring structure at the edge of the opening. Accordingly, a passage through which an imaging sample for nano magnetic particles can be inserted may be formed in the field-free region.

In this case, the pair of square magnets 121a and 121b and the pair of small magnet arrays 122a and 122b may be neodymium magnets (n30 grade). However, this is only an example, and the present invention is not limited thereto. That is, as the small magnets, a magnet having a stronger magnetism may be used, and a sharper field free may be obtained in proportion to the magnetic strength.

At this time, the pair of square magnets 121a and 121b and the pair of small magnet arrays 122a and 122b may form a magnetic field as shown in FIG. 5 . In this case, the magnetization direction of the magnet may be k=0 for the pair of small magnet arrays 122a and 122b.

In addition, according to the magnetic field formed by the pair of square magnets 121a and 121b and the pair of small magnet arrays 122a and 122b, a field-free image such as the simulation image shown in FIG. 6 may be generated.

As described above, a field-free region may be formed as an inner center of the pair of square magnets 121a and 121b and the pair of small magnet arrays 122a and 122b.

만큼 회전시킬 수 있다. 즉, MPI 이미징을 위한 필드프리 영역의 이동은 한 쌍의 사각 자석들(122a, 122b)를 XY 평면에서 좌우 및

만큼씩 180도 반복 회전하면서 필드프리 영역이 좌우 및

만큼 180도 회전되도록 할 수 있다. In addition, according to the embodiment, the pair of small magnet arrays 122a and 122b are fixed, and the pair of square magnets 121a and 121b are linearly moved in one direction by the first driving unit 140 and work direction and angle

can be rotated as much as That is, the movement of the field-free area for MPI imaging moves the pair of square magnets 122a and 122b to the left and right and left and right in the XY plane.

The field free area rotates left and right and

It can be rotated 180 degrees.

7 is a flowchart for describing a method for imaging nanomagnetic particles according to an embodiment.

Referring to FIG. 7 , in the method for imaging nanomagnetic particles according to the embodiment, the step of applying a signal to an excitation coil installed in a measurement head containing a sample containing the nanomagnetic particles ( S210 ) and between the same magnetic poles facing each other Moving the field-free region in which the magnetic field generated within the separation region is rare within the sample, and imaging the three-dimensional position distribution of the nano-magnetic particles included in the sample based on the detection signal output from the detection coil of the measuring head (S220~ S230) may be included.

In this case, the imaging of the three-dimensional position distribution (S220 to S230) includes generating a two-dimensional image that is a two-dimensional position distribution of the nano-magnetic particles included in the cross section of the sample based on the detection signal (S220) and horizontal to each other. The method may include generating a 3D image by synthesizing a plurality of 2D images corresponding to a plurality of cross-sections ( S230 ).

At this time, in the step (S220) of generating a two-dimensional image, the pair of square magnets are linearly moved in one direction (see FIGS. 8 to 12) or rotated to have a predetermined angle with one direction ( FIGS. 13 to 22 ). ) while generating a sinogram with a signal output from the detection signal according to the movement of the field-free region, and inverse Radon transform on the generated sinogram, a two-dimensional image may be generated.

8 to 12 are diagrams illustrating movement of a field-free line as a pair of square magnets move in one direction according to an embodiment.

Referring to FIG. 8 , as the pair of square magnets 122a and 122b moves to the right in a state where the field free line is located in the center of the sample, the field free line moves to the right by 1 step as shown in FIGS. 8 to 12 . A gradual shift is shown.

13 to 22 are diagrams illustrating rotation of a field-free line as a pair of square magnets rotate according to an embodiment.

(예컨대, 20deg)만큼 반시계 방향으로 회전함에 따라, 도 13 내지 22와 같이 필드프리 라인도

만큼 반시계 방향으로 회전되어 180도 회전되는 것이 도시되어 있다. Referring to FIG. 13 , in a state where the field-free line is located in the center of the sample, a pair of square magnets 122a and 122b

As it rotates counterclockwise by (eg, 20deg), the field free line is also shown as in FIGS. 13 to 22

Rotated counterclockwise by 180 degrees is shown.

In this case, the generating of the two-dimensional image may be repeated while moving the measuring head by a predetermined unit length in a direction perpendicular to the cross-section of the sample.

The field-free generator 120 according to the above-described embodiment may be utilized in a small MPI scanner.

At this time, when measuring a sample with a sample diameter of 20 mm or less, it can be used as a high-resolution scanner with a resolution of 1 mm or less as a scanner with a gradient field of FFL of 10 T/m.

23 to 26 are diagrams illustrating performance of a small MPI scanner to which a field-free generator is applied according to an embodiment.

23 is an xy-plane magnetic field measurement result, FIG. 24 is an xz-plane magnetic field measurement result, FIG. 25 is a z-axis magnetic gradient measurement result (10T/m), and FIG. 26 is a y-axis magnetic gradient measurement result (10T/m) m) is shown. That is, according to the embodiment, an FFL having a magnetic inclination (2T/m or more) required for clinical research can be made under realistic conditions.

Meanwhile, the field-free generator 120 according to the embodiment may facilitate the manufacture of MPI equipment capable of scanning human and animal brains.

27 to 30 are structural exemplary diagrams of a brain MPI scanner to which a field-free generator according to an embodiment is applied.

27 to 30, a device capable of scanning human and animal brains by allowing human brains and other animals to pass inside of the Holbach array magnet, and placing square magnets that fit it on the left and right can be developed In this way, it can be applied to equipment that scans other parts of the human body.

31 is a diagram showing the configuration of a computer system according to an embodiment.

The controller 130 according to the embodiment may be implemented in the computer system 1000 such as a computer-readable recording medium.

Computer system 1000 may include one or more processors 1010 , memory 1030 , user interface input device 1040 , user interface output device 1050 , and storage 1060 that communicate with each other via bus 1020 . can Additionally, the computer system 1000 may further include a network interface 1070 coupled to the network 1080 . The processor 1010 may be a central processing unit or a semiconductor device that executes programs or processing instructions stored in the memory 1030 or storage 1060 . The memory 1030 and the storage 1060 may be a storage medium including at least one of a volatile medium, a non-volatile medium, a removable medium, a non-removable medium, a communication medium, and an information delivery medium. For example, the memory 1030 may include a ROM 1031 or a RAM 1032 .

Although embodiments of the present invention have been described with reference to the accompanying drawings in the above, those of ordinary skill in the art to which the present invention pertains can implement the present invention in other specific forms without changing the technical spirit or essential features. You can understand that there is Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

Claims (20)

A hexahedral housing having an opening formed on one side thereof is formed so that the measuring head is inserted into the separation region,
a pair of square magnets respectively installed on two opposite sides of the four sides perpendicular to one side of the housing; and
A field-free generating device, characterized in that a pair of magnet arrays arranged at the edge of the opening in which a plurality of small magnets are installed on one side of the housing and the other side facing the one side, respectively. According to claim 2, wherein the plurality of small magnets,
Field-free generating device, characterized in that arranged in a circle at the edge of the opening. The method of claim 1, wherein the field-free area comprises:
Field-free generation device, characterized in that the field-free point (Field Free Point, FFP) or field-free line (Field Free Line, FFL). 6. The method of claim 5,
Field-free generating device, characterized in that it further comprises a first driving unit for linearly moving or rotating the pair of square magnets. a measuring head in which a through hole in which a sample containing magnetic nanoparticles is accommodated is formed, and an excitation coil and a detection coil are installed;
a field-free generator for forming a field-free region in which a magnetic field is thin in a spaced region between the same facing magnetic poles;
As the measuring head is positioned within the spaced region of the field-free generator, a signal is applied to the excitation coil, and the field-free region is controlled to move within the sample, and the nano-magnetism included in the sample is based on the detection signal output from the detection coil. Including a control unit for imaging the three-dimensional position distribution of the particles,
Field-free generator,
A nanomagnetic particle imaging apparatus comprising a pair of magnet arrays in which a pair of square magnets and a plurality of small magnets are arranged. The method of claim 5, wherein the field-free generator comprises:
Comprising a hexahedral housing having an opening formed on one side so that the measuring head is inserted into the spaced area,
A pair of square magnets are installed on each of two opposite sides of the four sides perpendicular to one side of the housing,
Nanomagnetic particle imaging apparatus, characterized in that a pair of magnet arrays arranged at the edge of the opening in which a plurality of small magnets are disposed on one side of the housing and the other side facing the one side, respectively. The method of claim 6, wherein the plurality of small magnets,
Nanomagnetic particle imaging device, characterized in that it is arranged in a circle at the edge of the opening. The method of claim 5, wherein the field-free area comprises:
Field-free point (Field Free Point, FFP) or field-free line (Field Free Line, FFL), characterized in that the nano-magnetic particle imaging apparatus. The method of claim 6, wherein the control unit,
Based on the detection signal, a two-dimensional image is generated, which is a two-dimensional position distribution of the nano-magnetic particles included in the cross section of the sample,
An apparatus for imaging nanomagnetic particles, characterized in that a 3D image is generated by synthesizing a plurality of 2D images corresponding to a plurality of cross-sections that are horizontal to each other. 10. The method of claim 9,
Nanomagnetic particle imaging apparatus, characterized in that it further comprises a first driving unit for linearly moving or rotating the pair of square magnets. 11. The method of claim 10, wherein the control unit,
By controlling the first driving unit, linear movement of the pair of square magnets in one direction and rotation in one direction and a predetermined angle are repeatedly performed,
An apparatus for imaging nanomagnetic particles, characterized in that a sinogram is generated with a signal output from the detection signal according to the movement of the field-free region, and a two-dimensional image is generated by inverse radon-transformation of the generated sinogram. 12. The method of claim 11,
Nanomagnetic particle imaging apparatus, characterized in that it further comprises a second driving unit for moving the measuring head to the spaced area through the opening of the field-free generator. The method of claim 12, wherein the control unit,
An apparatus for imaging nanomagnetic particles, characterized in that the two-dimensional image is repeatedly generated while the measuring head is moved by a predetermined unit length in a direction perpendicular to the cross-section of the sample. applying a signal to an excitation coil installed in a measurement head containing a sample containing magnetic nanoparticles; and
The three-dimensional position distribution of the nanomagnetic particles included in the sample is based on the detection signal output from the detection coil of the measuring head by moving the field-free area where the magnetic field generated within the spaced area between the same facing magnetic poles is rare within the sample. Including the step of imaging,
Field free area,
A method for imaging nanomagnetic particles, characterized in that a pair of square magnets and a plurality of small magnets are generated by a pair of arranged magnet arrays. 15. The method of claim 14, wherein the pair of square magnets,
The measuring head is installed on two opposite sides of the four sides perpendicular to one side in the housing of a hexahedron having an opening formed on one side so as to be inserted into the spaced area,
A pair of magnet arrays,
A nanomagnetic particle imaging method, characterized in that a plurality of small magnets are arranged at the edge of the opening on each of one side of the housing and the other side facing the one side. 16. The method of claim 15, wherein the plurality of small magnets,
Nanomagnetic particle imaging method, characterized in that it is arranged in a circle at the edge of the opening. The method of claim 15, wherein the field-free area,
Nanomagnetic particle imaging method, characterized in that the field free point (Field Free Point, FFP) or field free line (Field Free Line, FFL). The method of claim 15, wherein imaging the three-dimensional position distribution comprises:
generating a two-dimensional image that is a two-dimensional position distribution of magnetic nanoparticles included in a cross section of a sample based on the detection signal;
A method for imaging nanomagnetic particles, comprising: generating a three-dimensional image by synthesizing a plurality of two-dimensional images corresponding to a plurality of cross-sections that are horizontal to each other. The method of claim 18, wherein generating a two-dimensional image comprises:
While linearly moving a pair of square magnets in one direction or rotating to have a predetermined angle with one direction,
A method for imaging nanomagnetic particles, characterized in that a sinogram is generated with a signal output from a detection signal according to field-free region movement, and a two-dimensional image is generated by inverse radon transformation of the generated sinogram. The method of claim 19, wherein the generating of the two-dimensional image comprises:
A method for imaging nanomagnetic particles, characterized in that it is repeated while moving the measuring head by a predetermined unit length in a direction perpendicular to the cross-section of the sample.

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