JPH01305937A - Magnetic resonance diagnosis device - Google Patents

Abstract

PURPOSE:To arbitrarily use a variety of receiving/transmission coils and lighten the installation condition and permit the diagnosis in a variety of body attitude by arranging an inspected patient on a bed in the static magnetic field of the magnetic poles opposed in the horizontal direction and generating the magnetic resonance phenomenon at a specific position of the inspected patient by applying the inclined magnetic field and the high frequency magnetic field for excitation. CONSTITUTION:A static magnetic field B0 for generating the magnetic resonance is generated with the horizontal direction of the magnetic field, between the magnetic poles 11c1 and 11c2 of a static magnetic field magnet 11. Each inclined magnetic field coil 12 is installed onto the surfaces of the magnetic poles 11c1 and 11c2, and a variety of receiving and transmission coils are installed in the opposed space. A turning-up/down bed 13 is installed in a yoke part 11a. A sequencer 16 inputs a control signal into an inclined magnetic field power source 14 and a receiver/transmitter 15 by the instruction of a computer system 17, and the excitation due to the magnetic resonance is generated at a specific part of an inspected patient, and the induced magnetic resonance signal is taken into the system 17 and displayed on a monitor 18 through the reconstitution treatment. Therefore, a variety of body attitude diagnosis can be carried out, and the installation space of the bed 13 can be reduced, and a variety of receiving and transmission coils can be used according to the demand.

Description

[Detailed description of the invention] [Object of the invention] (Industrial application field) The present invention is directed to magnetic resonance (MR: a+agnetier
Regarding magnetic resonance diagnostic equipment that uses the phenomenon of morphological information such as slice images of a subject (living body) and functional information such as spectroscopy, it is particularly useful for diagnosis not only in the recumbent position but also in various body positions. The present invention relates to a magnetic resonance diagnostic device that enables this.

(Prior art) Magnetic resonance is a phenomenon in which an atomic nucleus with non-zero spin and magnetic moment placed in a static magnetic field resonantly absorbs and emits only electromagnetic waves of a specific frequency. The angular frequency ω0 (ωo−2π and 0.ν0
; Larmor frequency).

ω01γBO Here, γ is the gyromagnetic ratio specific to the type of atomic nucleus,
Moreover, Bo is the static magnetic field strength.

An apparatus that performs biological diagnosis using the above-mentioned principle processes electromagnetic waves of the same frequency as above, which are induced after the above-mentioned resonance absorption, to determine nuclear density, longitudinal relaxation time Tl, transverse relaxation time T2, and so on. Diagnostic information that reflects information such as flow and chemical shift, such as slice images of a subject, is obtained non-invasively.

Collecting diagnostic information using magnetic resonance can excite all parts of a subject placed in a static magnetic field and collect signals, but there are limitations in the equipment configuration and clinical aspects of imaging images. Due to this request, the actual device is designed to excite a specific region and collect its signals.

In this case, the specific region to be imaged is generally a sliced region with a certain thickness;
Magnetic resonance signals (MR multiplied signals) of echo signals and FID signals from this slice site are collected by performing a data encoding process many times, and these data groups are subjected to image reconstruction processing using, for example, a two-dimensional Fourier transform method. By doing so, an image of the specific slice region is generated.

For example, Fig. 4 shows the configuration of an apparatus using a static magnetic field generating magnet 1 with the magnetic field direction of the static magnetic field Bo in the horizontal direction (transverse magnetic field method), and Fig. 5 shows the configuration of an apparatus using the static magnetic field generation magnet 1 with the magnetic field direction of the static magnetic field Bo in the horizontal direction. This figure shows the configuration of a device using a static magnetic field generating magnet 2 in a vertical direction (vertical magnetic field type), each of which is composed of an electromagnet or a permanent magnet.

Generally, in the magnet 1 shown in FIG. 4, a superconducting coil or a normal conducting coil is arranged in a cylinder having openings at both ends in the horizontal direction, and an inner cylindrical space connected to the openings is used as an examination subject introduction space. Further, the magnet 2 shown in FIG. 5 has magnetic poles of unit coils or permanent magnets facing each other at a distance in the vertical direction, and this facing space is used as the subject introduction space.

In both methods, a bed 3 with a slide top plate is installed close to the magnet 12, and the subject P placed on the slide top plate of this bed 3 is placed in a horizontal direction. It is designed to be inserted into the test subject introduction space. Therefore, in the method shown in FIG. 4, the direction of the body axis of the subject P and the direction of the magnetic field are approximately the same, and in the method shown in FIG.
The body axis direction of the subject P and the magnetic field direction are approximately perpendicular to each other.

- Also, according to the principle of magnetic resonance, it is a condition that the static magnetic field B and the excitation high-frequency magnetic field B1 are perpendicular to each other, so the saddle-shaped coil 4 shown in FIG. 6(a) is used as a commonly used transmitting and receiving coil. The surface coil 5 shown in FIG. 6(b) and the solenoid coil 6 shown in FIG. 6(C) have limited applications. That is, in the horizontal magnetic field method shown in FIG. 4, the saddle-shaped coil 4 shown in FIG. 6(a) and the surface coil 5 shown in FIG. 6(b) can be used, and high sensitivity characteristics can be expected. Solenoid coil 6 shown in FIG. 6(c)
cannot be used.

In the vertical magnetic field method shown in FIG. 5, the solenoid coil 6 shown in FIG. 6(C) can be used, but the saddle-shaped coil 4 shown in FIG. The surface coil 5 shown in FIG. 6(b), which is suitable for diagnosis of localized areas, cannot be used.

Furthermore, when considering the required installation space for the device, since the magnet 1.2 and the bed 3 are installed in parallel in either method, the horizontal direction of the device is approximately 5 meters, and this type of device This, combined with the increased weight of the device, has made the installation conditions stricter.

In addition, in both of the above methods, the subject P is in a lying position within the subject introduction cavity of magnets 1 and 2, and therefore the diagnosis can only be made in the lying position, so depending on the diagnosis content. There may be a problem. For example, the spinal cord and vertebrae are subject to excessive stress during normal life, that is, in a standing position. Therefore, for patients with vertebral hernia (subject P) for whom this stress is a factor, image diagnosis under this stress state is essentially required. However, since both of the above methods perform image diagnosis only when the subject P is in the lateral recumbent position, it is not possible to perform image diagnosis in the stress state described above.

(Problems to be Solved by the Invention) As described above, in the conventional transverse magnetic field type or vertical magnetic field type devices, various transmitting and receiving coils cannot be used as desired, and the installation conditions are strict. Furthermore, there were other problems such as the inability to perform diagnosis in various body positions.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a magnetic resonance diagnostic apparatus that can use various types of transmitting and receiving coils as desired, eases installation conditions, and allows diagnosis in various body positions.

[Structure of the Invention] (Means for Solving the Problems) The present invention has a structure in which the following means are taken to solve the above problems and achieve the objects.

That is, the present invention includes a static magnetic field magnet having horizontally opposed magnetic poles, a gradient magnetic field coil, a transmitting/receiving coil, and an upright bed arranged in the opposing space, and the opposing space generated by the static magnetic field coil. A subject is placed in a static magnetic field using the tilting bed, and a gradient magnetic field is applied to the subject by the gradient magnetic field coil, and a high-frequency magnetic field for excitation is applied by the transmitting/receiving coil. A magnetic resonance phenomenon is caused in a specific part of the examiner, and the magnetic resonance signals induced by this phenomenon are processed by the transmitter/receiver coil and subjected to signal processing, thereby creating an image of at least one of morphological information and functional information of the specific part. It is characterized by being configured to do so.

(Function) According to such a configuration, a static magnetic field is generated in the space facing the static magnetic field magnet, and in the facing space, a patient can be placed in various body positions on a reclining bed for diagnosis. can. In this case, since the raising/lowering bed can be installed in the opposing space, the required installation space is smaller than in the case of the horizontal magnetic field method or the vertical magnetic field method, and the installation conditions are relaxed. Also,
Since the direction of the static magnetic field is perpendicular to the subject's body axis,
Various transmitting and receiving coils such as saddle coils, surface coils, solenoid coils, etc. can be used as desired.

(Example) Hereinafter, an example of the magnetic resonance diagnostic apparatus according to the present invention will be described as a first example.
This will be explained with reference to the figures.

As shown in FIG. 1, the static magnetic field magnet 11 has a yoke portion 11a placed on its base, and leg portions 11bl and 11b2 extending upward from both ends of the main yoke portion 11a. and,
This leg 11bl.

At the end of 11b2, horizontally opposing magnetic poles 11cl,
11c2.

With this configuration, a static magnetic field B is generated between the magnetic poles 11c1 and 11c2 to generate magnetic resonance. is generated with the magnetic field direction horizontal. In this case, a shim coil (not shown) may be provided to correct the uniformity of the static magnetic field.

Further, gradient magnetic field coils 12 are provided on the surfaces of the magnetic poles 11cl and 11c2, respectively. Furthermore, the magnetic pole 11c
Various types of transmitting/receiving coils such as saddle-shaped coils, surface coils, and solenoid coils are provided in the space facing the coils 1 and 11c2 (not shown).

On the other hand, an elevating bed 13 is installed on the yoke portion 11a of the static magnetic field magnet 11, and a top plate 13 a l of this elevating bed 13 is installed.
A subject (not shown) can be placed thereon. This top plate 13a consists of a footrest 13a1 and a body rest 13a2. Thereby, the magnetic field direction of the static magnetic field and the subject's body axis direction become perpendicular.

In addition to the above main body configuration, a gradient magnetic field power supply 14 that drives the gradient magnetic field coil 12 is provided, and a transmitter/receiver 15 that drives the transmitter/receiver coil is provided.

The gradient magnetic field power supply 14 and the transmitter/receiver 15 are connected to the sequencer 1
6, and this sequencer 16 is controlled by a computer system 17 including a reconfiguration processing system.

The image generated by this computer system 17 is displayed on a monitor 18, and the computer system 17 controls a bed control section 19, which controls the raising and lowering of the bed 13. It has become.

Next, the operation of the present embodiment configured as described above will be explained with reference to FIG. 1 and FIG. 2 showing the operation of the upright bed 13. First, the computer system 17 and bed control section 19
Accordingly, as shown in FIG. 2(a), the top plate 13a of the reclining bed 13 is placed in a standing position, and in this standing position, the subject (not shown) places his feet on the footrest 13a1 and brings his torso to the body rest 13a2. Hang it up and stand in a natural position. Next, in order to set the desired part of the subject in the optimum magnetic field space or to obtain the desired body position, the top plate 13a is tilted to be in the tilted state (FIG. 2(b)) or in the horizontal state (FIG. 2(b)). Set as shown in figure (c).

Here, for example, a surface coil (not shown) is placed as a transmitting/receiving coil at a desired part of the subject, and a command for executing an appropriate pulse sequence is given to the sequencer 16 from the computer system 17. A control signal is given to the transceiver 15, and the gradient magnetic field coil 1 is controlled by the pulse power related to the pulse sequence.
2 and drive the transmitting and receiving coils.

As a result, a specific region of the subject is excited by magnetic resonance, and the induced magnetic resonance signals are then collected by the transmitter/receiver coil and taken into the computer system 17 via the transmitter/receiver 15, and reconstructed into, for example, a slice image. etc. are generated and displayed on the monitor 18.

As described above, according to the present embodiment, a static magnetic field is generated in the space facing the static magnetic field magnet 11, and the patient is placed in various positions in the facing space using the upright bed 13 for diagnosis. be able to. Therefore, image diagnosis can be performed not only when the subject is in a lying position but also in a stressed state, such as in a standing position.

Furthermore, since the raising/lowering bed 13 is installed in the opposing space, the required installation space is smaller than in the case of the horizontal magnetic field method or the vertical magnetic field method, and the installation conditions are relaxed.

Furthermore, since the direction of the static magnetic field is perpendicular to the subject's body axis, various types of transmitting/receiving coils such as saddle-shaped coils, surface coils, solenoid coils, etc. can be used as desired.

In addition, in the configurations shown in FIGS. 4 and 5, the subject perceives a feeling of being confined in a narrow space within the magnets 1 and 2, but in this embodiment, the subject feels trapped in a narrow space within the magnets 1 and 2. Upper or magnetic pole 11cl.

Since the upper part of the space facing 11C2 is open, the subject on the upright bed 13 perceives a sense of openness and is in a mentally favorable situation. It is particularly suitable for subjects who tend to have claustrophobia.

The present invention is not limited to the above embodiments.

For example, if the raising/lowering bed 13 is provided with a lifting mechanism, the required movable range of the raising/lowering bed 13 can be reduced, making the installation conditions more suitable. Regarding static magnetic field magnets, as shown in Figure 3, a U-shaped iron core 2
Magnetic pole portions 20bl extend upward from both ends of the magnetic yoke 20a.

The conductor 21 may be wound around the conductor 20b2 to constitute an electromagnetic static field magnet.

In the above case, the conductor 21 can be either a normal conducting wire or a super conductive wire. In addition, the stand-up bed 1
A mechanism for fixing the transmitting/receiving coil may be attached to the top plate 13 of No. 3. The invention can be modified in various ways without departing from the gist of the invention.

[Effects of the Invention] As described above, the present invention includes a static magnetic field magnet having horizontally opposed magnetic poles, a gradient magnetic field coil, a transmitting/receiving coil, and an upright bed disposed in the opposing space, and the static magnetic field A subject is placed on the upright bed in a static magnetic field in the facing space generated by the coil, and a gradient magnetic field is applied to the subject by the gradient magnetic field coil, and a high frequency wave for excitation is applied to the subject by the transmitting/receiving coil. A magnetic field is applied to cause a magnetic resonance phenomenon in a specific region of the subject, and a magnetic resonance signal induced by this phenomenon is sent to the transmitter/receiver coil.
The configuration is configured to image at least one of the morphological information and functional information of the specific region by collecting the information from the user and performing signal processing, so that there is no static in the space facing the static magnetic field magnet in which the upright bed is placed. Since a magnetic field is generated, the patient can be placed in a variety of positions for diagnosis using the tilting bed, and since the tilting bed can be installed in the opposing space, the required installation space is reduced to the horizontal magnetic field method. It is smaller than the vertical magnetic field method, the installation conditions are relaxed, and the direction of the static magnetic field is perpendicular to the subject's body axis, so it can be used with various types of coils such as saddle-shaped coils, surface coils, solenoid coils, etc. Transmitting/receiving coils can be used as desired.

Therefore, according to the present invention, it is possible to provide a magnetic resonance diagnostic apparatus that can use various types of transmitting and receiving coils as desired, eases installation conditions, and allows diagnosis in various body positions.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an embodiment of a magnetic resonance diagnostic apparatus according to the present invention, FIG. 2 is a diagram showing the operation of a reclining bed in the same embodiment, and FIG. 3 is a diagram showing another embodiment of the present invention. Figures 4 and 5 show the configuration of a conventional example, in which Figure 4 is a configuration diagram of a transverse magnetic field type device, and Figure 5 is a configuration diagram of a vertical magnetic field type device. , FIG. 6 is a diagram showing the transmitting/receiving coil. 11. 20... Static magnetic field magnet, lla, 20a...
Yoke part, 11 bl, 11 b2... leg part,
I.C.I. 11 c2=, 20al, 20a2-...magnetic pole, 12
, , Gradient magnetic field coil, 13... Raising bed, 13a
... Top plate, 14... Gradient magnetic field power supply, 15... Transmitter/receiver, 16... Sequencer, 17... Computer system, 18... Monitor, 19... Bed control section. Applicant's representative Patent attorney Takehiko Suzue, Figure 1 J (a) Figure 2 L J (C) Figure 3 Figure 4 Figure 5 (a) (b) (c) Rin Figure 6

Claims (1)

[Claims] A static magnetic field magnet having horizontally opposed magnetic poles, a gradient magnetic field coil, a transmitting/receiving coil, and an upright bed arranged in the opposing space, and a static magnetic field generated by the static magnetic field coil in the opposing space. A subject is placed on the upright bed, a gradient magnetic field is applied to the subject by the gradient magnetic field coil, and a high-frequency magnetic field for excitation is applied by the transmitting/receiving coil to a specific region of the subject. A magnetic resonance phenomenon is generated, and magnetic resonance signals induced by this phenomenon are collected by the transmitter/receiver coil and subjected to signal processing, thereby imaging at least one of morphological information and functional information of the specific region. A magnetic resonance diagnostic device characterized by: