JPH01284241A - Magnetic resonance imaging device - Google Patents

Abstract

PURPOSE:To permit the smooth communication between an inspected patient and an operator without obstructing the photographing operation by installing a photographing suspending means for suspending the magnetic resonance imaging photographing and a photographing restarting means. CONSTITUTION:When an inspected patient arranged in a cradle 16 or an operator arranged in a console part 15 desires communication, MRI photographing is suspended by allowing a pulse sequence controller 11 to intercept the interlocking of an inclined magnetic field control system consisting of an inclined magnetic field coil 5 and an inclined magnetic field coil electric power source 8 and an NMR signal receiving system consisting of an NMR signal prove 4, NMR signal receiving circuit 9, and an NMR signal A/D converter 10 by the operation of switches 3 and 12. While, an RF transmission system consisting of an RF coil 6 and an RF transmission circuit 7 carriers out the application of RF pulses continuously. On the completion of communication, the pulse sequence controller 11 operates the above-described inclined magnetic field control system and the NMR signal receiving system again in interlocking by the operation of the switch 3 and the switch 12, and MRI photographing is restarted.

Description

Detailed Description of the Invention [Objective of the Invention (Industrial Application Field) The present invention relates to a magnetic resonance imaging apparatus (hereinafter referred to as MR
In particular, the present invention relates to an improvement of a magnetic resonance imaging apparatus equipped with an interaction system that enables interaction between a subject and an operator during MR imaging.

(Prior art) As is well known, MRIffi generates weak nuclear magnetic resonance signals (hereinafter referred to as RF pulses) induced by applying an excitation high-frequency magnetic field (hereinafter referred to as RF pulses) to a living body placed in a static magnetic field. By detecting the NMR signal (called an NMR signal) and performing image reconstruction processing on the detected tomographic image, for example, a tomographic image is displayed on a CRT.
For the purpose of determining the generation position of the R signal, linear gradient magnetic fields are sequentially applied in two or three orthogonal directions as the image is made two-dimensional or three-dimensional. Also, the detected N
The MR signal is digitized by an A/D converter for processing using a computer such as CT.

'Dialogue between the subject and the operator during MRIffa is not possible because the MRI imaging space (hereinafter referred to as the inside of the mount) is sealed with an electromagnetic shielding structure for the purpose of preventing the intrusion of external radio waves and reducing the leakage of magnetic fields to the outside. This is done through microphones and speakers installed inside and outside the pedestal.

(Problems to be Solved by the Invention) However, in the conventional method described above, the noise generated by the switching that sequentially exchanges the gradient magnetic fields in each direction interferes with smooth communication. This situation not only interferes with smooth MRI imaging, but also, in the event of an emergency,
This is a matter of concern as it may threaten the safety of the subjects.

The present invention has been made in view of the above problems, and
The object of the present invention is to provide an MRI equipment equipped with a dialogue system that enables smooth communication between the subject and the operator without interfering with the review activities during imaging.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention utilizes input operations by subjects or operators, or output conditions of a monitor device regarding biological information such as electrocardiographic waveforms and respiratory movements. In response to an input operation, the gradient magnetic field control system and the NMR signal receiving system are stopped in conjunction with each other, while the RF pulse is continued to be applied, thereby interrupting the MRI imaging.

In addition, after communication is completed, the gradient magnetic field control system and NMR
The configuration allows MRI imaging to be resumed by restarting the signal reception system in conjunction with the system.

(Function) The MRI apparatus to which the present invention is applied has the above configuration.
During communication, switching of the gradient magnetic field, which is the main source of noise, is stopped as the gradient magnetic field control system is stopped, thereby ensuring a state in which smooth communication is possible. Also, during communication, NM
Since the R signal receiving system is also stopped, unnecessary signals are not detected.

On the other hand, since RF pulses are continuously applied during communication,
The spin system within the subject's body, which is the source of the NMR signal, is maintained in the state at the time the imaging was interrupted. After the communication is completed, the gradient magnetic field control system and the NMR signal reception system are reactivated from the state at which the imaging was interrupted, and the imaging is resumed, so there is no effect due to the interruption of the communication.

(Example) FIG. 1 is a schematic circuit diagram of an MRI apparatus to which the present invention is applied, and FIG. 2 is a schematic configuration diagram of the same apparatus.

In this embodiment, the inside of the cradle 16 and the console 1
On top of 5, a normal microphone tos beaker 2 and microphone 13.
In addition to each speaker 14 being installed, a switch 3 and a switch 12 directly connected to the pulse sequence control device 11 are also installed.

Subject or console section 15 placed in the pedestal 16
When an operator located at the station wishes to communicate, he operates the switches 3 to 12 to cause the pulse sequence control device 11 to control the gradient 1ifi field control system consisting of the gradient magnetic field coil 5 and the gradient magnetic field power source 8, and the NMR signal probe. 4. NMR signal receiving circuit 9 and NMR signal A/
The NMR signal receiving system consisting of the D converter 10 is stopped in conjunction with the D converter 10 to interrupt the MRI imaging. On the other hand, the RF transmission system consisting of the RF coil 6 and the RF transmission circuit 7 continues to R.
Apply F pulse.

At the end of the communication, the pulse sequence control device 11 causes the gradient magnetic field control system and the NMR signal reception system to restart in conjunction with each other by operating the switches 3 to 12, and MRI imaging begins.

Note that the operation of the above-mentioned dialogue system can also be controlled based on information from a monitor device such as electrocardiographic waveforms and respiratory movements.

In addition, by operating the switch, the pulse sequence control device 11 during communication is completely stopped, and after communication is completed, the preparatory pulse sequence is used to reproduce the state immediately before MRI imaging is interrupted, and then MRI imaging is resumed. Alternatively, it is also possible to restart the MR 111 imaging by setting the pulse sequence control device to a state several stages before the interruption of MRI imaging, and to process the overlapped portion of data later.

As described above, in the MRr device to which an embodiment of the present invention is applied, when the subject or operator wishes to communicate, the switching of the gradient magnetic field, which is the main noise source, is stopped by operating the switch described above, so communication can be carried out smoothly. I can do it. In addition, since the NMR signal receiving system is also stopped in conjunction, unnecessary signals during communication are not detected, and on the other hand, the state of the spin system within the subject's body is maintained as it was when the MRII fi imaging was interrupted due to the continuous application of RF pulses. The gradient magnetic field control system and the NMR signal receiving system are restarted in conjunction with each other by a switch operation after the end of the communication, and the MRIlfff is immediately activated.
i Shadow is resumed.

Therefore, in the MRI IV unit to which an embodiment of the present invention is applied, smooth communication between the subject and the operator can be achieved without interfering with the imaging activities during the MRI III imaging.

Note that in FIGS. 1 and 2, 17 represents a control/mechanical part of the MRI apparatus, and 18 represents a main magnet.

[Effects of the Invention] As described above, in the MR device to which the present invention is applied, the noise caused by switching of the gradient magnetic field is stopped by the input operation of the above-mentioned dialogue system, and smooth communication becomes possible. In addition, NMR in conjunction with the gradient magnetic field control system
By stopping the signal receiving system, unnecessary signals during communication are not detected. Furthermore, by continuing to apply the RF pulse, the spin system within the subject's body is maintained in the same state as when the MRI imaging was interrupted. As a result, the gradient magnetic field control system and the NMR signal receiving system are restarted in conjunction with the input operation for restarting imaging after the end of communication, so that MR1 imaging is promptly restarted, and there is no effect of interruption due to communication.

[Brief explanation of the drawing]

FIG. 1 is a schematic circuit diagram of an MRI apparatus to which the present invention is applied, and FIG. 2 is a schematic configuration diagram of the same apparatus. 1... Speaker 2... Microphone 3... Switch 4... NMR signal probe 5... Gradient lti field coil 6... RF coil 7... RF transmission circuit 8... Gradient magnetic field rIi Source 9...NMR signal receiving circuit 10...A/D converter 11...Pulse sequence control device 12...Switch 13...Microphone 14...Speaker 15...Console (operation unit) 16... Inside the mount (imaging section) 17... Control/mechanical section 18... Main magnet

Claims (5)

[Claims] (1) A magnetic resonance imaging apparatus equipped with a dialogue system that enables dialogue between a subject housed in a magnetic resonance imaging imaging space and an operator outside the imaging space, the dialogue system being operated. imaging interrupting means for interrupting magnetic resonance imaging when a predetermined input operation is performed to stop the operation of the dialogue system; A magnetic resonance imaging apparatus comprising: a restart means; and a magnetic resonance imaging apparatus. (2) The imaging interrupting means performs control to stop the gradient magnetic field control system and the nuclear magnetic resonance signal receiving system by movement, while interrupting the magnetic resonance imaging imaging while continuing to apply the excitation high-frequency magnetic field. The magnetic resonance imaging apparatus according to claim 1, characterized in that: (3) The magnetic resonance imaging according to claim (1), wherein the imaging restart means performs control to resume magnetic resonance imaging by restarting a gradient magnetic field control system and a nuclear magnetic resonance signal receiving system in conjunction with each other. Resonance imaging device. (4) The magnetic resonance imaging apparatus according to claim 1, wherein the start of control by the imaging interrupting means and the imaging restarting means is executed by an input operation by a subject or an operator. (5) The start of control by the imaging interrupting means and the imaging restarting means is performed by an input operation responsive to the status of an output signal of a monitor device regarding biological information such as an electrocardiogram waveform or respiratory motion. The magnetic resonance imaging apparatus according to item (1).