JP6791908B2 - Magnetic resonance imaging device - Google Patents

Description

Embodiments of the present invention relate to a magnetic resonance imaging apparatus.

In the imaging of an MRI image by a magnetic resonance imaging (MRI) device, the subject is moved into a bore of the gantry device while being placed on a top plate. The gantry device generates a high-frequency magnetic field and a gradient magnetic field based on a pulse sequence according to the imaging conditions, and collects the magnetic resonance signal generated from the subject by this.

The gantry device includes a static magnetic field magnet that generates a uniform static magnetic field in the bore, a gradient magnetic field coil that is arranged inside the static magnetic field magnet and generates a gradient magnetic field in the bore, and the like. The static magnetic field magnet, the gradient magnetic field coil, and the like are arranged outside the bore tube for securing the bore. In addition, rails and the like for running the top plate are arranged in the bore of the gantry device.

In recent years, in order to improve the habitability of a subject at the time of imaging, a large-diameter MRI apparatus in which the bore space is physically as wide as possible has been developed. However, there is a limit to widening the bore diameter from the viewpoint of the performance of the RF coil and the image quality of the MRI image.

Japanese Unexamined Patent Publication No. 2011-87904

An object to be solved by the present invention is to provide a magnetic resonance imaging apparatus capable of enhancing the habitability of a subject with a simple configuration.

The magnetic resonance imaging apparatus according to the embodiment includes a gantry, a high frequency coil, and a coil support portion. The gantry includes a high frequency coil and a static magnetic field magnet and a gradient magnetic field coil provided so as to surround the imaging region. The high frequency coil has a coil pattern having an axial length shorter than the axial length of the gradient magnetic field coil. The coil support portion supports the high frequency coil. Further, the coil support portion has an axial length longer than the axial length of the gradient magnetic field coil, has a substantially cylindrical shape, and has an inner diameter that radially expands outward toward at least one axial end portion. With such an inclination, the static magnetic field magnet is supported only at a position axially farther than the axial end portion of the inclined magnetic field coil, and the inclined portion and the inclined magnetic field coil in the coil supporting portion are supported. At least one of the sound insulating material and the sound absorbing material is arranged in the space between them.

FIG. 1 is a functional block diagram showing a configuration of an MRI apparatus according to the first embodiment. FIG. 2 is a diagram showing an example of the coil support portion. FIG. 3 is a diagram showing an example of the coil support portion. FIG. 4 is a diagram showing an example of the coil support portion according to the first embodiment. FIG. 5 is a diagram showing an example of the coil support portion according to the first embodiment. FIG. 6 is a diagram showing an example of the coil support portion according to the first embodiment. FIG. 7 is a diagram showing an example of a method for manufacturing a coil support portion according to the first embodiment. FIG. 8 is a diagram showing an example of a method for manufacturing a coil support portion according to the first embodiment. FIG. 9 is a diagram showing a modified example of the coil support portion according to the first embodiment.

Hereinafter, the magnetic resonance imaging apparatus according to the embodiment will be described with reference to the drawings.

(First Embodiment)
FIG. 1 is a functional block diagram showing the configuration of the MRI apparatus 100 according to the first embodiment. In the following, the magnetic resonance imaging apparatus will be referred to as an MRI (Magnetic Resonance Imaging) apparatus.

As shown in FIG. 1, the MRI apparatus 100 includes a static magnetic field magnet 101, a static magnetic field power supply 102, a gradient magnetic field coil 103, a gradient magnetic field power supply 104, a sleeper 105, a sleeper control unit 106, and a WB (Whole Body). ) Coil 107, transmission unit 108, reception coil 109, reception unit 110, sequence control unit 120, and computer 130. The MRI apparatus 100 does not include the subject P (for example, the human body). Further, the configuration shown in FIG. 1 is only an example.

The static magnetic field magnet 101 is a hollow magnet formed in a substantially cylindrical shape, and generates a static magnetic field in the internal space. The static magnetic field magnet 101 is, for example, a superconducting magnet or the like, and is excited by receiving a current supply from the static magnetic field power supply 102. The static magnetic field power supply 102 supplies an electric current to the static magnetic field magnet 101. The static magnetic field magnet 101 may be a permanent magnet, and in this case, the MRI apparatus 100 does not have to include the static magnetic field power supply 102. Further, the static magnetic field power supply 102 may be provided separately from the MRI apparatus 100.

The gradient magnetic field coil 103 is a hollow coil formed in a substantially cylindrical shape, and is arranged inside the static magnetic field magnet 101. The gradient magnetic field coil 103 is formed by combining three coils corresponding to the x, y, and z axes orthogonal to each other, and these three coils individually supply current from the gradient magnetic field power supply 104. In response, a gradient magnetic field is generated in which the magnetic field strength changes along the x, y, and z axes. Gradient of each axis of inclination x generated by the magnetic field coils 103, y, and z, for example, slice encode gradient magnetic field G _SE (or a slice selection gradient G _SS), the phase encoding gradient G _PE, and the frequency encode gradient The magnetic field is _GRO . The gradient magnetic field power supply 104 supplies a current to the gradient magnetic field coil 103.

The sleeper 105 includes a top plate 105a on which the subject P is placed, and under the control of the sleeper control unit 106, the top plate 105a is placed in a state where the subject P is placed, and the cavity of the gradient magnetic field coil 103 ( Insert it into the imaging port). Normally, the sleeper 105 is installed so that the longitudinal direction is parallel to the central axis of the static magnetic field magnet 101. The sleeper control unit 106 drives the sleeper 105 under the control of the computer 130 to move the top plate 105a in the longitudinal direction and the vertical direction.

The WB coil 107 is arranged inside the gradient magnetic field coil 103, receives an RF pulse from the transmission unit 108, and generates a high-frequency magnetic field. Further, the WB coil 107 receives a magnetic resonance signal (hereinafter, appropriately “MR (Magnetic Resonance) signal”) emitted from the subject P due to the influence of a high frequency magnetic field, and outputs the received MR signal to the receiving unit 110. The WB coil 107 is an example of an RF coil arranged inside the static magnetic field magnet 101.

The transmission unit 108 supplies the WB coil 107 with an RF pulse corresponding to the Larmor frequency determined by the type of target atom and the magnetic field strength.

The receiving coil 109 is arranged inside the gradient magnetic field coil 103, and receives the MR signal emitted from the subject P due to the influence of the high frequency magnetic field. When the receiving coil 109 receives the MR signal, it outputs the received MR signal to the receiving unit 110.

The WB coil 107 and the receiving coil 109 described above are merely examples. For example, the WB coil 107 and the receiving coil 109 may be configured by combining one or more of a coil having only a transmitting function, a coil having only a receiving function, and a coil having a transmitting / receiving function. ..

The receiving unit 110 detects the MR signal output from the receiving coil 109 and generates MR data based on the detected MR signal. Specifically, the receiving unit 110 generates MR data by digitally converting the MR signal output from the receiving coil 109. Further, the receiving unit 110 transmits the generated MR data to the sequence control unit 120. The receiving unit 110 may be provided on the gantry device side including the static magnetic field magnet 101, the gradient magnetic field coil 103, and the like.

The sequence control unit 120 takes an image of the subject P by driving the gradient magnetic field power supply 104, the transmission unit 108, and the reception unit 110 based on the sequence information transmitted from the computer 130. Here, the sequence information is information that defines a procedure for performing imaging. The sequence information includes the strength of the current supplied to the gradient magnetic field coil 103, the timing of supplying the current, the strength of the RF pulse supplied by the transmitting unit 108 to the WB coil 107, the timing of applying the RF pulse, and the MR signal of the receiving unit 110. The timing to detect is defined. For example, the sequence control unit 120 is an integrated circuit such as an ASIC (Application Specific Integrated Circuit) and an FPGA (Field Programmable Gate Array), and an electronic circuit such as a CPU (Central Processing Unit) and an MPU (Micro Processing Unit).

Further, when the sequence control unit 120 receives the MR signal data from the reception unit 110 as a result of controlling the gradient magnetic field power supply 104, the transmission unit 108, and the reception unit 110 to image the subject P, the sequence control unit 120 calculates the received MR signal data. Transfer to 130.

The computer 130 controls the entire MRI apparatus 100, generates an MR image, and the like. For example, the computer 130 causes the sequence control unit 120 to execute an imaging sequence based on the imaging conditions input from the operator. Further, the computer 130 reconstructs an image based on the MR signal data transmitted from the sequence control device 120. The computer 130 stores the reconstructed image in the storage unit and displays it on the display unit. The computer 130 is, for example, an information processing device such as a computer.

By the way, the WB coil 107 is arranged at an appropriate position between the central axis and the gradient magnetic field coil 103. For example, an RF shield is usually attached to the inner peripheral surface of the gradient magnetic field coil 103. Since the RF power of the WB coil 107 decreases as it approaches the RF shield, it is preferable that the WB coil 107 is arranged at a position away from the gradient magnetic field coil 103. However, the farther the position of the WB coil 107 is from the gradient magnetic field coil 103, the narrower the space (bore) into which the subject is inserted, and the less comfortable it is. Therefore, the WB coil 107 is arranged at an appropriate position from the viewpoint of maintaining the RF power while ensuring the width of the bore.

Here, in order to arrange the WB coil 107 at an appropriate position, a coil support portion (bobbin) that supports the WB coil 107 is used. The WB coil 107 is installed on the outer peripheral surface of the coil support portion, for example. The coil support portion is formed by adjusting the size of the inner diameter (inner circumference) of the WB coil 107 so as to be arranged at an appropriate position, and is arranged inside the gradient magnetic field coil 103.

2 and 3 are views showing an example of the coil support portion. 2 and 3 illustrate cross-sectional views of the gantry in the yz plane passing through the central axis of the static magnetic field magnet 101, respectively.

In the example shown in FIG. 2, the coil support portion 20 is formed so that the length in the axial direction is shortened. Specifically, the axial length of the coil support portion 20 is formed to be the shortest within the range in which the WB coil 107 can be arranged. The coil support portion 20 is supported by a cylindrical member 21 having the same length as the static magnetic field magnet 101. Further, the cylindrical member 21 is supported by, for example, a plurality of support members 22a, 22b, 22c, 22d. As a result, the WB coil 107 is arranged at an appropriate position. Inside the cylindrical member 21, for example, the sleeper rail 11 is installed by the support members 10a and 10b. Further, the gantry is covered with the gantry cover 12 except for the surface covered by the sleeper rail 11. Further, a sound insulating material and a sound absorbing material are arranged in the spaces 23a and 23b between the gantry cover 12 and the cylindrical member 21.

In the example shown in FIG. 3, the coil support portion 30 has a length similar to that of the static magnetic field magnet 101 and is formed parallel to the central axis. The coil support portion 30 is supported by, for example, a plurality of support members 31a, 31b, 31c, 31d. As a result, the WB coil 107 is arranged at an appropriate position. The sleeper rail 11 is installed inside the coil support portion 30 by, for example, the support members 10a and 10b. Further, the gantry is covered with the gantry cover 12 except for the surface covered by the sleeper rail 11.

Here, when the coil support portion 20 is used (FIG. 2), the WB coil 107 is supported by the coil support portion 20 having the minimum necessary size, so that the habitability of the subject can be improved. However, in this case, the number of parts increases as compared with the case where the coil support portion 30 is used (FIG. 3), and the manufacturing cost increases.

On the other hand, when the coil support portion 30 is used (FIG. 3), the coil support portion 30 is supported by the static magnetic field magnet 101 without using other support members, so that a simple configuration can be realized. However, in this case, the inner diameter of the coil support portion 30 is the same as that of the portion where the WB coil 107 is arranged over the entire length in the axial direction, so that the habitability of the subject is lowered.

Therefore, the MRI apparatus 100 according to the first embodiment includes a coil support portion 40 which is formed in a substantially cylindrical shape and supports the WB coil 107 in order to improve the habitability of the subject with a simple configuration. The substantially cylindrical shape referred to here includes not only a cylindrical shape but also a distorted cylindrical shape within a range that does not significantly impair the function of the MRI apparatus 100. That is, the substantially cylindrical shape includes, for example, a case where the cross section of the xy plane is a perfect circle or an ellipse.

(Appearance of coil support 40)
The external features of the coil support portion 40 will be described with reference to FIGS. 4 to 6. 4 to 6 are views showing an example of the coil support portion 40 according to the first embodiment. FIG. 4 illustrates a cross-sectional view of the coil support portion 40 (cross-sectional view in the yz plane passing through the central axis). FIG. 5 illustrates a cross-sectional view of the gantry (cross-section in the yz plane passing through the central axis). FIG. 6 illustrates a perspective view showing the positional relationship between the coil support portion 40 and the WB coil 107. Here, after briefly explaining each figure, the external features of the coil support portion 40 will be described in detail.

As shown in FIG. 4, the coil support portion 40 mainly has three ranges 40a, 40b, and 40c. The range 40a is formed in a substantially cylindrical shape in which a predetermined range including the center of the magnetic field is parallel to the axial direction. Further, each of the ranges 40b and 40c is formed in a substantially cylindrical shape that is not parallel to the axial direction between both ends of the coil support portion 40 and the range 40a. Specifically, each of the ranges 40b and 40c is formed in a substantially cylindrical shape with an inclination so as to spread from the center side of the magnetic field toward both ends. Further, each of the ranges 40d and 40e is a range of a predetermined distance from both ends of the coil support portion 40 toward the central direction in the axial direction.

In the first embodiment, for convenience of explanation, the coil support portion 40 will be divided into the respective ranges 40a, 40b, 40c, 40d, and 40e, but the external features of the coil support portion 40 will be described. It's just one way to do it. Therefore, for example, it does not mean that the coil support portion 40 is individually formed in each range 40a, 40b, 40c, 40d, 40e. The molding method of the coil support portion 40 will be described later.

As shown in FIG. 5, the WB coil 107 is installed in the range 40a of the coil support portion 40. The coil support portion 40 is supported by, for example, a plurality of support members 41a, 41b, 41c, 41d. The support members 41a, 41b, 41c, 41d are, for example, bases for supporting a predetermined range of the outer peripheral surface of the coil support portion 40. As a result, the WB coil 107 is arranged at an appropriate position. Inside the coil support portion 40, for example, the sleeper rail 11 is installed by the support members 10a and 10b. Further, the gantry is covered with the gantry cover 12 except for the surface covered by the sleeper rail 11. Further, the gradient magnetic field coil 103 is supported by a static magnetic field magnet by a support member (not shown).

Note that FIG. 5 is merely an example. For example, the number of support members 41a, 41b, 41c, 41d does not necessarily have to be four. For example, the MRI apparatus 100 does not have to have the support members 41c and 41d.

As shown in FIG. 6, the coil support portion 40 has a cylindrical shape having a perfect circular shape in the cross section of the xy plane. Specifically, the shape of the end face and the shape of the cross section of the xy plane in the range 40a are perfect circles. Further, in the coil support portion 40, the WB coil 107 is arranged on the outer peripheral surface of the range 40a. Specifically, in the coil support portion 40, a coil pattern of the WB coil 107 is formed on the outer peripheral surface of the range 40a, and a capacitor or a capacitor is arranged. As an example, the range 40a of the coil support portion 40 is the minimum range in which the coil pattern of the WB coil 107 can be formed.

Note that FIG. 6 is merely an example. For example, as described above, the coil support portion 40 may have an elliptical cylindrical shape in the cross section of the xy plane. In this case, only one of the shape of the end face and the shape of the cross section of the xy plane in the range 40a may be an ellipse, or both may be an ellipse. That is, the shape of the end face and the shape of the cross section of the xy plane in the range 40a may be different.

Hereinafter, the external features of the coil support portion 40 will be described in detail. The coil support portion 40 is formed so that a range 40a including an installation surface on which the WB coil 107 is installed is parallel to the axial direction. Here, the inner diameter of the range 40a is determined so that the WB coil 107 is arranged at an appropriate position. Further, the axial length of the range 40a is longer than the axial length of the WB coil 107 and shorter than the axial length of the gradient magnetic field coil 103. Further, each of the ranges 40b and 40c has an inclination so as to extend from the center in the axial direction toward both ends (arrows in FIG. 6). In other words, in the coil support portion 40, the inner diameter (inner circumference) of both ends of the coil support portion 40 is larger than the inner diameter (inner circumference) of the range 40a. As a result, the coil support portion 40 can improve the habitability of the subject.

When the shape of the coil support portion 40 in the cross section of the xy plane is an elliptical cylindrical shape, the inner diameter thereof is not unique, but at least the inner circumferences of both ends of the coil support portion 40 are the inner circumferences of the range 40a. Greater.

Further, the axial length of the coil support portion 40 is longer than the axial length of the gradient magnetic field coil 103. Further, the outer peripheral surfaces of the ranges 40d and 40e of the coil support portion 40 are formed parallel to the inner peripheral surface of the static magnetic field magnet 101. Therefore, the coil support portion 40 can be supported by the support members 41a, 41b, 41c, 41d having a simple structure. As a result, the coil support portion 40 can support the WB coil 107 with a simple configuration without increasing the number of parts. The axial lengths of the ranges 40d and 40e are shorter than the length of the portion where the static magnetic field magnet 101 is longer than both end faces of the gradient magnetic field coil 103.

Further, the thickness of each of the ranges 40d and 40e of the coil support portion 40 is thicker than the thickness of the range 40a. Here, the thickness of the range 40a is preferably made thin within a range in which the coil support portion 40 can support the WB coil 107 in order to enhance the comfort of the subject. On the other hand, the thickness of each of the ranges 40d and 40e of the coil support portion 40 is preferably made thick so that the coil support portion 40 is not deformed by the load applied to the position. Specifically, the range 40d and 40e are loaded with the sleeper rail 11, the top plate 105a, and the subject. If the support members 41a, 41b, 41c, 41d that support the coil support portion 40 and the support members 10a, 10b that support the sleeper rail 11 are misaligned from the coil support portion 40, the coil support portion Since a force due to a moment is also applied to 40, it is preferable to make it thicker.

Further, by using the coil support portion 40, spaces 42a and 42b are created. The space 42a is, for example, a space between the outer peripheral surface of the range 40b and the inner peripheral surface of the gradient magnetic field coil 103. Further, the space 42b is, for example, a space between the outer peripheral surface of the range 40c and the inner peripheral surface of the gradient magnetic field coil 103. Here, since the coil support portion 40 has only one component, the spaces 42a and 42b when the coil support 40 is used are, for example, the spaces 23a when the coil support 20 having a large number of components is used. It will be wider than 23b. As a result, the coil support portion 40 can secure a wide space in which the sound insulating material and the sound absorbing material can be arranged.

The above example is just an example. For example, in the example of FIG. 5, it is described that there is a gap between the gantry cover 12 inside the bore and the coil support portion 40, but the embodiment is not limited to this. For example, the gantry cover 12 and the inner peripheral surface of the coil support portion 40 may be brought into close contact with each other so as not to leave this gap. Further, the gantry cover and the coil support portion 40 may or may not be arranged in parallel. However, in order to improve the comfort of the subject, it is preferable that the gap between the gantry cover 12 and the coil support portion 40 is small, and the gantry cover 12 is formed along the inner peripheral surface of the coil support portion 40. It is preferable to be done.

(Characteristics according to the manufacturing method of the coil support portion 40)
An example of a method for manufacturing the coil support portion 40 will be described with reference to FIGS. 7 and 8. 7 and 8 are views showing an example of a method for manufacturing the coil support portion 40 according to the first embodiment.

As shown in FIGS. 7 and 8, the coil support portion 40 according to the first embodiment is molded (molded) by, for example, a filament winding (FW) method. Specifically, in the FW method, the fiber bundle (roving) 50 is impregnated with a resin (thermosetting resin) as an adhesive to give a constant tension, and a clue is provided to the rotating mandrel (mold) 51. It is traversed, wound regularly, wound to a predetermined thickness, and then heat-cured. Then, the coil support portion 40 is obtained by pulling out the mandrel 51 after molding the outer shape with a lathe.

Here, the fiber bundle 50 is a bundle in which a plurality of fibers are arranged in a predetermined direction. That is, since a bundle in which a plurality of fibers are arranged in a predetermined direction is wound, the coil support portion 40 has a structure in which the plurality of fibers are arranged in a predetermined direction. Further, the wound fiber has a length of at least one inner circumference in the range 40a. The fiber is, for example, a glass fiber. The resin is, for example, a polyester resin or an epoxy resin.

Further, as the FW pattern, hoop winding (FIG. 7) and helical winding (FIG. 8) are adopted. The hoop winding is a method of winding the fiber bundle 50 around the mandrel 51 in a direction of about 90 degrees with respect to the axial direction. As a result, the fiber bundle 50 is wound around the mandrel 51 without leaving a large gap. The layer of the fiber bundle 50 wound by the hoop winding is referred to as a hoop winding layer. Further, the helical winding is a method of winding the fiber bundle 50 around the mandrel 51 at a predetermined oblique angle with the axial direction. As a result, the number of places where the fiber bundles 50 intersect can be increased, and the strength of the molded body (coil support portion 40) can be increased. The layer of the fiber bundle 50 wound by the helical winding is referred to as a helical winding layer.

For example, in the coil support portion 40, a hoop winding and a helical winding are appropriately combined and adopted. That is, the coil support portion 40 has a hoop winding layer and a helical winding layer. As a result, the coil support portion 40 is adjusted to an appropriate strength.

Further, for example, the coil support portion 40 has a hoop winding layer as the first layer from the inner peripheral surface. Specifically, in the FW method, first, the fiber bundle 50 is wound around the mandrel 51 by hoop winding. As a result, the coil support portion 40 can form the bore of the subject with a uniform layer.

The examples of FIGS. 7 and 8 are merely examples. For example, the coil support portion 40 does not necessarily have to have a hoop winding layer as the first layer from the inner peripheral surface. Further, for example, the coil support portion 40 may be created by using only one of the hoop winding and the helical winding FW pattern.

As described above, the MRI apparatus 100 according to the first embodiment is formed in a substantially cylindrical shape and includes a coil support portion 40 that supports the WB coil 107. In this coil support portion 40, a range 40a including an installation surface on which the WB coil 107 is installed is formed parallel to the axial direction, and the inner circumferences of both ends of the coil support portion 40 are from the inner circumference of the range 40. large. Therefore, the MRI apparatus 100 can improve the habitability of the subject with a simple configuration. For example, the MRI apparatus 100 does not increase the number of parts, which contributes to the reduction of manufacturing cost.

(Modified example of the first embodiment)
The shape of the coil support portion 40 is not limited to the shapes described in FIGS. 4 to 6. For example, the coil support portion 40 may be formed to be thicker in the ranges 40b and 40c.

FIG. 9 is a diagram showing a modified example of the coil support portion 40 according to the first embodiment. FIG. 9 illustrates a cross-sectional view of the gantry (cross-section in the yz plane passing through the central axis). As shown in FIG. 9, the coil support portion 40 can be formed so that the thickness of the ranges 40b and 40c is thicker than the thickness described in FIGS. 4 to 6. Specifically, the coil support portion 40 is formed so as to satisfy the positions corresponding to the spaces 42a and 42b in FIG. As a result, the thickness of the coil support portion 40 is increased, so that the sound insulation performance of the coil support portion 40 is improved. In this case, since the inner peripheral surface of the coil support portion 40 is the same as the inner peripheral surface of the coil support portion 40 of FIGS. 4 to 6, the habitability of the subject is not deteriorated.

In the above-described embodiment, for example, the case where the range 40b and the range 40c are formed as targets has been described, but the embodiment is not limited to this. For example, the range 40b and the range 40c may have different shapes as long as the functions of the MRI apparatus 100 are not significantly impaired. The shapes of the range 40b and the range 40c may have, for example, a shape in which the side into which the subject is inserted is large.

Further, in the above-described embodiment, the case where each of the ranges 40b and 40c is formed in a substantially cylindrical shape with an inclination has been described, but the embodiment is not limited to this. For example, each of the ranges 40b and 40c may be formed in a curved substantially cylindrical shape so as to extend in an arc from the center side of the magnetic field toward both ends. Further, each of the ranges 40b and 40c may have not only inclination and curvature but also unevenness, for example.

As shown in FIG. 4, the coil support portion 40 mainly has three ranges 40a, 40b, and 40c. The range 40a includes an installation surface on which the WB coil 107 is installed, and is formed in a substantially cylindrical shape parallel to the axial direction. Further, each of the ranges 40b and 40c is formed in a substantially cylindrical shape that is not parallel to the axial direction between both ends of the coil support portion 40 and the range 40a. Specifically, each of the ranges 40b and 40c is formed in a substantially cylindrical shape with an inclination so as to extend from the center in the axial direction toward both ends. Further, each of the ranges 40d and 40e is a range of a predetermined distance from both ends of the coil support portion 40 toward the central direction in the axial direction.

According to at least one embodiment described above, the habitability of the subject can be enhanced by a simple configuration.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, as well as in the scope of the invention described in the claims and the equivalent scope thereof.

100 MRI device 107 WB coil 40 Coil support

Claims (13)

A gantry with a high-frequency coil and a static magnetic field magnet and a gradient magnetic field coil provided to surround the imaging region, and
The high frequency coil having a coil pattern having an axial length shorter than the axial length of the gradient magnetic field coil, and the high frequency coil.
A coil support portion that supports the high-frequency coil is provided.
The coil support portion
It has a shaft length longer than the shaft length of the gradient magnetic field coil and has a shaft length longer than that of the gradient magnetic field coil.
It is substantially cylindrical and has an inclination such that the inner diameter radiates outward toward at least one axial end.
The static magnetic field magnet is supported only at a position axially farther than the axial end of the gradient magnetic field coil.
At least one of the sound insulating material and the sound absorbing material is arranged in the space between the inclined portion and the inclined magnetic field coil in the coil support portion.
Magnetic resonance imaging device. The thickness of both ends of the coil support portion is thicker than the thickness of the coil support portion in a predetermined range including the magnetic field center.
The magnetic resonance imaging apparatus according to claim 1. The outer peripheral surface within a predetermined distance from both ends of the coil support portion toward the central direction in the axial direction is parallel to the inner peripheral surface of the static magnetic field magnet.
The magnetic resonance imaging apparatus according to claim 1 or 2. The coil support portion is formed in a substantially cylindrical shape with an inclination or a substantially cylindrical shape curved from each end surface to a predetermined range including the center of the magnetic field, and is a portion formed in the substantially cylindrical shape. The outer peripheral surface of the magnetic field magnet is parallel to the inner peripheral surface of the static magnetic field magnet.
The magnetic resonance imaging apparatus according to any one of claims 1 to 3. The coil support portion is formed in a substantially cylindrical shape in which the cross section of the xy plane is a perfect circle or an ellipse.
The magnetic resonance imaging apparatus according to any one of claims 1 to 4. The coil support portion is composed of fibers and resin, and has a structure in which a plurality of the fibers are arranged in a predetermined direction.
The magnetic resonance imaging apparatus according to any one of claims 1 to 5. The fiber has at least the length of one inner circumference in a predetermined range including the center of the magnetic field.
The magnetic resonance imaging apparatus according to claim 6. The coil support portion has a hoop winding layer and a helical winding layer.
The magnetic resonance imaging apparatus according to claim 6 or 7. The coil support portion has the hoop winding layer as the first layer from the inner peripheral surface.
The magnetic resonance imaging apparatus according to claim 8. The fiber is composed of glass fiber.
The resin is composed of a polyester resin or an epoxy resin.
The magnetic resonance imaging apparatus according to any one of claims 6 to 9. The space is located on the inner peripheral side of the gradient magnetic field coil.
The magnetic resonance imaging apparatus according to any one of claims 1 to 10. The sound insulation performance or sound absorption performance in the range corresponding to the inclined portion in the central axis direction of the static magnetic field magnet is higher than the sound insulation performance or sound absorption performance in the range corresponding to the high frequency coil in the central axis direction.
The magnetic resonance imaging apparatus according to any one of claims 1 to 11. A gantry with a high-frequency coil and a static magnetic field magnet and a gradient magnetic field coil provided to surround the imaging region, and
The high frequency coil having a coil pattern having an axial length shorter than the axial length of the gradient magnetic field coil, and the high frequency coil.
A coil support portion that supports the high-frequency coil is provided.
The coil support portion
It has a shaft length longer than the shaft length of the gradient magnetic field coil and has a shaft length longer than that of the gradient magnetic field coil.
It is substantially cylindrical and has an inclination such that the inner diameter radiates outward toward at least one axial end.
The static magnetic field magnet is supported only at a position axially farther than the axial end of the gradient magnetic field coil.
Molded by the filament winding method,
At least one of the sound insulating material and the sound absorbing material is arranged in the space between the inclined portion and the inclined magnetic field coil in the coil support portion.
Magnetic resonance imaging device.

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