JPH10127595A - Magnetic resonance tomograph - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To enable tomography to be performed without causing a patient M to feel pressure during imaging. SOLUTION: In the magnetic resonance tomographic imaging apparatus of the present invention, a static magnetic field forming magnet 1 for forming a static magnetic field in an imaging region space S is disposed on both lateral sides of the patient M along the body axis direction Z of the patient M. In addition, the gantry 1 has a shape in which the upper part of the imaging region space S is open, and the patient M who is lying on his back on the tabletop 2 has opened the front of his eyes to the front. Medium, patient M does not feel any pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a nuclear magnetic resonance (Nu)
The present invention relates to an apparatus for performing tomography of a subject (patient) using the phenomenon of clear Magnetic Resonance (NMR).
The present invention relates to a technique for allowing a subject to spend a calm mood without feeling oppressed during imaging.

2. Description of the Related Art In recent years, magnetic resonance tomography apparatuses that perform imaging by utilizing the NMR phenomenon have made remarkable progress in the field of medical form diagnosis. In the case of the magnetic resonance tomographic imaging apparatus, as shown in FIG. 4, an imaging region space S and a magnet for forming a static magnetic field (hereinafter abbreviated as “magnet” as appropriate) 32 for forming a static magnetic field in the imaging region space S are provided. Gantry 31, a top plate 33 for carrying the patient M into the imaging region space S, and a pulse magnetic field signal for excitation (RF
Signal) and detection of a nuclear magnetic resonance signal (NMR signal) emitted from the patient M (also referred to as an RF coil or the like).

In this device, the top plate 32 is indicated by an arrow A
After the patient M is carried into the imaging region space S from the opening 34 of the gantry 31 by moving in the direction of, the nuclear magnetic resonance detected from the patient M by the high-frequency probe P under the application of the static magnetic field by the magnet 32. The image is reconstructed based on the signal to create and display a tomographic image. The tomographic image captured in this manner is provided to a doctor and used to make an accurate diagnosis.

[0003]

However, in the case of the above-mentioned conventional apparatus, there is a problem that the patient M in the imaging region space S feels oppression during imaging. As shown in FIG.
The magnet 32 sandwiching the imaging region space S is cylindrical,
At the same time, the imaging region space S also has a cylindrical shape surrounded by the surroundings, so that during imaging, the patient M feels pressed into a narrow enclosed space, and feels a sense of oppression. In particular, a magnetic resonance tomography apparatus is unsuitable for a person with claustrophobia, and may even be painful during tomography.

As shown in FIG. 5, a magnet 37 for forming a static magnetic field of a type C and a magnet 38 for forming a static magnetic field of a vertically divided type shown in FIG. There is also a magnetic resonance tomography apparatus. However, in this case as well, in the imaging region space S, the patient M lying on his back is still in a state where his / her eyes are closed immediately before the eyes, so that the patient M
I feel the same pressure.

[0005] In view of the above problems, an object of the present invention is to provide a magnetic resonance tomographic imaging apparatus capable of performing tomographic imaging without causing the patient M to feel pressure during imaging.

[0006]

In order to achieve the above object, a magnetic resonance tomography apparatus according to the present invention provides a static magnetic field for forming a uniform static magnetic field in an imaging region space in which a tomographic image of a subject is to be taken. A gantry in which magnets for formation are arranged to face each other so as to sandwich an imaging region space, a top plate for carrying the subject into the imaging region space of the gantry, and a pulse magnetic field signal for excitation of the subject (RF signal ) And a high-frequency probe for detecting a nuclear magnetic resonance signal (NMR signal) emitted from the subject, and
In a magnetic resonance tomographic imaging apparatus configured to perform image reconstruction based on a nuclear magnetic resonance signal detected by the high-frequency probe, the magnet for forming a static magnetic field may have a body axis of the subject on both lateral sides of the subject. The gantry is arranged along the direction, and the gantry has a shape in which the upper part of the imaging region space is open.

(Operation) Next, the operation when tomographic imaging is performed by the magnetic resonance tomography apparatus of the present invention will be described. The subject to be imaged, which is laid on the top of the magnetic resonance tomography apparatus, is carried into the imaging region together with the high-frequency probe by moving the top into the gantry. Then, under the application of a static magnetic field by a static magnetic field forming magnet disposed on both sides of the subject along the body axis direction of the subject, application of a pulse magnetic field signal for excitation to the subject by a high frequency probe and The detection of the nuclear magnetic resonance signal emitted from the subject is performed, so that the imaging proceeds.

[0008] The imaging region space in the gantry of the magnetic resonance tomography apparatus of the present invention is a space whose upper part is open, the upper part of the subject lying on his back is not closed, and the part from the front of the patient's eyes is opened. ing. That is, in the magnetic resonance tomographic imaging apparatus of the present invention, an upper open type magnet disposed along the body axis direction of the subject on both left and right sides of the subject is employed as the static magnetic field forming magnet. Accordingly, the photographing area space can be made a space whose upper side is opened in accordance with this.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing the entire configuration of a magnetic resonance tomographic imaging apparatus according to an embodiment, and FIG.

The magnetic resonance tomography apparatus according to the embodiment includes a gantry 1 having an imaging region space S for performing tomography of a subject M, and a top board 2 for carrying the patient M into the imaging region space S of the gantry 1. In addition, an operation / control console 3 for controlling the operation of the top 2 and reconstructing an image is provided.

The gantry 1 has a housing 1a having a concave shape with a vertical cross section, and a space (space) as a photographing area space S is provided at the center of the housing 1a from the front surface to the rear surface. That is, the housing 1a of the gantry 1 has the bottom 1b and the side walls 1c and 1d rising vertically along both sides of the bottom 1b.
The space between c and 1d is the photographing area space S.
Further, a magnet 4 for forming a static magnetic field is provided in the housing 1a so as to sandwich the imaging region space S. The static magnetic field forming magnet 4 applies a uniform static magnetic field to the imaging region space S. Further, a gradient magnetic field generating coil 5 is also provided in the housing 1a. Then, a required magnetic field is applied to the imaging region space S at an appropriate timing by the static magnetic field forming magnet 4 and the gradient magnetic field generating coil 5 under the control of the operation / control console 3.

On the other hand, in front of the gantry 1, a bed 7 which moves up and down in accordance with expansion and contraction of the base 6 is installed, and the top plate 2 is arranged on the bed 7 as shown by an arrow A. The top board 2 is configured to reciprocate between the bed 7 which is a standby position and the imaging area space S of the gantry 1. Therefore, the patient M is carried into the imaging region space S as the tabletop 2 moves to the imaging region space S of the gantry 1 in front while the patient M with the high frequency probe P mounted thereon. The control necessary for moving the top 2 is performed by the operation / control console 3.

The high-frequency probe P worn by the patient M shown in FIG. 1 is a band-shaped high-frequency probe for a body used for imaging the chest and abdomen. The high-frequency probe P used in the present invention is Not only a body part but also a suitable high-frequency probe manufactured according to an imaging part such as a head part or a knee part is used. The high-frequency probe P is located in the imaging region space S together with the patient M during imaging, and
NM released from the patient M while applying the F signal
The R signal is detected. And an operation and control console 3
Executes signal processing based on the NMR signal detected by the high-frequency probe P to perform image reconstruction, and displays a tomographic image on the screen of the display monitor 8 as necessary.

Next, the configurations of the imaging region space S and the static magnetic field forming magnet 4, which are features of the present invention, will be specifically described. As shown in FIG. 1, the gantry 1 of the embodiment has a structure in which the upper part of the photographing area space S is not closed and is opened. In the magnetic resonance tomographic imaging apparatus of the present invention, the static magnetic field forming magnets 4 are arranged on both lateral sides of the patient M along the body axis direction Z of the patient M, and the upper open type magnet is open at the top. Therefore, the upper part of the photographing area space S can be opened.
Unless the static magnetic field forming magnet 4 in the housing 1a is an open top type magnet, a structure that opens the upper part of the imaging region space S cannot be provided.

The static magnetic field forming magnet 4 includes a gantry 1
Coil housings 4a and 4b, and a coil housing 4 having a concave shape with a vertical cross section in conformity with the shape of the housing 1a
and a connecting portion 4c connecting the lower ends of the coils a and 4b, and superconducting coils 10 and 11 are installed in the coil housing portions 4a and 4b, respectively. A pair of superconducting coils 1
0 and 11 are electrically connected by wirings 12 and 13 passing through the connection portion 4c. Then, as a current flows in the superconducting coils 10 and 11 in a direction indicated by an arrow I, a uniform static magnetic field is formed in the imaging region space S. In addition,
The direction of the static magnetic field formed by the static magnetic field forming magnet 4 is a direction crossing the imaging region space S (a direction perpendicular to the body axis direction Z) as indicated by an arrow H.

Next, the imaging operation of the patient M in the embodiment apparatus having the above configuration will be described with reference to the drawings. First, as shown in FIG.
The patient M is laid on his back, and the high-frequency probe P is wrapped around the body and worn. Next, by moving the tabletop 2 toward the gantry 1 and moving it to the imaging region space S while the patient M equipped with the high-frequency probe P is mounted thereon, as shown by a dashed line in FIG. The patient M is carried into the imaging region space S and set. In this way, when the patient M is carried into the imaging region space S and preparations are completed, imaging is started. That is, under the application of the static magnetic field by the magnet 4, the gradient magnetic field is applied by the gradient magnetic field generating coil 5 and the RF signal is applied to the patient M by the high frequency probe P, while the NM emitted from the patient M is applied.
The R signal is detected by the high frequency probe P and transmitted to the console 3 for operation and control. Operation and control console 3
Executes signal processing based on the high-frequency NMR signal to perform image reconstruction and displays a tomographic image on the screen of the display monitor 8.

In the apparatus of the embodiment, the upper part of the photographing area space is not closed as in the conventional apparatus, and the upper part of the photographing area space S is completely open as shown in FIG. Since the patient M who is lying on his back with his eyes open is open, he can spend a calm mood in the gantry 1 without taking any feeling of oppression during shooting. Upon completion of the imaging, the top 2 is immediately retracted together with the patient M, exits the imaging region space S, and returns to the standby position on the bed 7.

Next, a magnetic resonance tomography apparatus according to another embodiment will be described. FIG. 3 is a perspective view showing a configuration of a gantry 21 of another embodiment device. In the other embodiments, only the configuration of the gantry 21 is different, and the other configuration is the same as that of the previous embodiment. Therefore, only the gantry 21 will be described, and the description of the other parts will be omitted.

As shown in FIG. 3, a gantry 21 of another embodiment has a housing 21a having a U-shaped horizontal section, and a photographing area space S at the center of the housing 21a from the front to the back. Space (space) is provided. That is, the housing 21a of the gantry 21
Has a rear wall 21b and side walls 21c and 21d extending forward from both side ends of the rear wall 21b.
The space between c and 21d is the photographing area space S. Further, a static magnetic field forming magnet 22 is disposed in the housing 21a along the body axis direction Z of the patient M so as to sandwich the imaging region space S. The configuration is such that a static magnetic field is applied. Also, a gradient magnetic field generating coil 23 is provided in the housing 21a.

The static magnetic field forming magnet 22 also has a U-shaped cross section similar to the shape of the housing 21a of the gantry 21. The magnet 22 for forming a static magnetic field includes a coil storage portion 22a, 22b and a coil storage portion 22a, 22 that are opposed to each other with the imaging region space S therebetween.
2b and a connecting portion 22c for connecting the rear end side. The superconducting coil 2 is provided in each of the coil storage portions 22a and 22b.
4, 25 are installed. The superconducting coils 24 and 25 are connected by wirings 26 and 27 passing through the connection part 22c.
Then, as a current flows in the superconducting coils 24 and 25 in a direction indicated by an arrow I, a uniform static magnetic field is formed in the imaging region space S. The direction of the static magnetic field formed by the static magnetic field forming magnet 22 is a direction (a direction perpendicular to the body axis direction Z) that crosses the imaging region space S as indicated by an arrow H.

Since the photographing operation of the other embodiment apparatus having the above-described configuration is substantially the same as that of the previous embodiment, the description is omitted. Of course, in the other embodiments, as shown in FIG. 3, the upper part of the photographing area space S is completely open, and the top plate 2 that has entered the gantry 21.
Since the patient's M lying on his back on top is open in front of his / her eyes, he / she can feel calm during shooting without any feeling of oppression.

The present invention is not limited to the above embodiment, but can be modified as follows. (1) In both of the above embodiments, the upper part of the photographing area space S is completely open. However, for example, a bar is passed above the photographing area space S, and A configuration in which only the upper part of the space S is closed is also a modified example of the present invention. If the patient M is not completely in front of his eyes, but is still open, the patient M will not have the feeling of being trapped, and the feeling of oppression will be considerably reduced.

(2) In both of the above embodiments, the superconducting coil is used as the magnet for forming the static magnetic field. However, permanent magnets are used instead of the superconducting coil on both sides of the imaging region space S. The configuration in which the components are arranged to face each other is a modified example.

[0024]

According to the magnetic resonance tomography apparatus according to the present invention, the imaging region space in the gantry is open at the top, and the subject lying on the top plate in a supine position. Because the eyes are open to the front, during shooting,
The subject can spend a calm mood in the gantry without feeling any oppression.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an overall configuration of a magnetic resonance tomography apparatus according to an embodiment.

FIG. 2 is a front view showing a configuration around a top plate and a gantry of the embodiment device.

FIG. 3 is a perspective view showing a gantry of another embodiment apparatus.

FIG. 4 is a perspective view showing a configuration around a top plate and a gantry of a conventional apparatus.

FIG. 5 is a perspective view showing a static magnetic field forming magnet of another conventional device.

FIG. 6 is a perspective view showing a static magnetic field forming magnet of another conventional device.

[Explanation of symbols]

 1, 21 ... gantry 2 ... top plate 4, 22 ... static magnetic field forming magnet 9, 10 ... superconducting coil P ... high frequency probe M ... patient S ... imaging area space Z ... body axis direction (of the subject)

Claims (1)

[Claims] 1. A gantry, wherein a magnet for forming a static magnetic field for forming a uniform static magnetic field in an imaging region space in which a tomographic image of a subject is to be taken is disposed opposite to each other so as to sandwich the imaging region space. A top plate for carrying the specimen into the imaging area of the gantry, application of an excitation pulse magnetic field signal (RF signal) to the subject, and detection of a nuclear magnetic resonance signal (NMR signal) emitted from the subject. A magnetic resonance tomography apparatus comprising a high-frequency probe, and configured to perform image reconstruction based on a nuclear magnetic resonance signal detected by the high-frequency probe,
The static magnetic field forming magnets are arranged on both sides of the subject along the body axis direction of the subject, and the gantry has a shape in which an upper part of an imaging region space is opened. Magnetic resonance tomography apparatus.