JPH0563166B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention generates a nuclear magnetic resonance (hereinafter referred to as "MR") phenomenon in a subject, detects the induced MR image signal (MRI), and detects the induced MR image signal (MRI). By obtaining projection information of the planned tomographic plane and performing image reconstruction processing, image information reflecting at least one of the spin density and relaxation time constant of a certain atomic nucleus in the subject is obtained and used for diagnosis. The present invention relates to a diagnostic MRI device.

[Technical background of the invention and its problems] In a diagnostic MRI apparatus, a subject is placed in a uniform static magnetic field, a gradient magnetic field is superimposed on the uniform static magnetic field, and an excitation rotating magnetic field is applied to detect MR phenomena. give rise to

FIG. 2 shows a schematic cross-sectional view of a conventional MRI apparatus.

The configuration of this device includes a superconducting coil 6 that generates a uniform static magnetic field, a gradient magnetic field coil 4 fixed to the superconducting coil 6, a transmitter coil 1 that generates the excitation rotating magnetic field, and a receiver that detects the MR signal. It consists of a coil 2 and a bed 3 on which a subject 8 is placed.

According to the above device, the gradient magnetic field coil 4 is deformed by receiving a force corresponding to the current due to the electromagnetic force of the current flowing therein and the static magnetic field generated by the superconducting coil 6. Since this current changes over time, the applied force also changes, and this deformation causes vibration.

Therefore, the conventional device has the following drawbacks. That is, transmitting coil 1, receiving coil 2,
Since the bed 3 is placed on the gradient magnetic field coil 4, the vibrations of the gradient magnetic field coil 4 are transmitted and these also vibrate. This vibration adversely affected the detection of MR signals and degraded the quality of image information.
Further, this vibration, along with the noise generated thereby, made it difficult for the patient placed on the bed 3 to live comfortably.

[Object of the Invention] The present invention has been made in view of the above circumstances, and provides an MRI system in which the vibrations of the gradient magnetic field coils do not have an adverse effect on the MR signal detection system, and in which vibrations and noise are not easily transmitted to the subject. The purpose is to provide equipment.

[Summary of the Invention] The present invention fixes a holding member to a superconducting coil by a supporting member inside the gradient magnetic field coil, independently of the gradient magnetic field coil, and a transmitting coil, a receiving coil, and a bed inside the gradient magnetic field coil. It is characterized by achieving the above purpose by placing the following.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the same reference numerals are given to parts common to the conventional example.

FIG. 1 shows one embodiment of the configuration of the present invention. In the figure, 6 is a superconducting coil for generating a static magnetic field, and a cylindrical holding member 5, for example, is fixed to the superconducting coil 6 inside the gradient magnetic field coil 4 by a supporting member 7. The transmitting coil 1 and the receiving coil 2 are attached to the inside of the cylindrical holding member 5, and are attached to the bed 3 on which the subject 8 is placed.
is also movably placed inside the cylindrical holding member 5 via a guide rail. Note that the holding member 5 is made of, for example, synthetic resin.

The operation of the device configured as above will be explained. According to the above configuration, since the cylindrical holding member 5 is fixed to the superconducting coil 6 independently of the gradient magnetic field coil 4, vibrations of the gradient magnetic field coil 4 are hardly transmitted to the holding member 5. Therefore, the vibrations of the gradient magnetic field coils are not transmitted to the transmitting coil 1, receiving coil 2, bed 3, and subject 8 placed inside the holding member 5. Also,
Since the holding member 5 functions as a sound insulating wall, the noise generated from the vibration of the gradient magnetic field coil 4 is also extremely small for the subject compared to the conventional device.

Although one embodiment of the present invention has been described in detail above, the present invention is not limited to the above-mentioned embodiment.
It goes without saying that various modifications are included within the scope of the invention. For example, in the embodiment described above, the holding member has a cylindrical shape, but the holding member is not necessarily limited to the cylindrical shape, and may have a notch in the middle.
Further, the material of the holding member is not limited to synthetic resin, and any material may be used as long as it does not affect the magnetic field. Furthermore, it is also applicable to devices using normal conducting coils instead of superconducting coils.

[Effects of the Invention] As described above, according to the present invention, the vibration of the gradient magnetic field coil does not have an adverse effect on the MR signal detection system, and vibrations and noise are not easily transmitted to the subject.
MRI equipment can be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an apparatus according to an embodiment of the present invention, and FIG.
The figure is a schematic cross-sectional view of a conventional MRI apparatus. 1... Transmitting coil, 2... Receiving coil, 3...
bed, 4... gradient magnetic field coil, 5... holding member, 6... superconducting coil, 7... supporting member, 8...
...Subject.

Claims (1)

[Claims] 1. By causing a nuclear magnetic resonance phenomenon in a subject, detecting the induced nuclear magnetic resonance signal, and performing image reconstruction processing by obtaining projection information of a planned tomographic plane of the subject, In a diagnostic nuclear magnetic imaging apparatus that obtains image information that reflects at least one of the spin density and relaxation time constant of a specific atomic nucleus and provides it for diagnosis, a tilting is used to place a transmitter coil 1, a receiver coil 2, and a bed 3. magnetic field coil 4
a holding member 5 provided inside the holding member 5;
and a support member 7 for fixing the magnetic field coil 6 to the static magnetic field coil 6 independently of the gradient magnetic field coil 4.