JPH04322640A - Mr imaging apparatus with measuring function - Google Patents

Abstract

PURPOSE:To improve through put by a method wherein a pressure sensor is provided on a hydraulic cylinder of vertically driving system for a bed on which a person to be inspected is placed to measure the weight thereof while a photosensor is provided on a table frame of the bed to measure his length and a signal is processed with a computer to output energy of the optimum irradiation pulse. CONSTITUTION:A pressure sensor 12 is provided on a hydraulic cylinder 9 to move a table frame 6 of a bed 3 vertically and a pressure change owing to the weight of a person 4 to be inspected is detected to be sent to a first signal conversion means 13. A photosensor 14 is provided on the table frame 6, light of the photosensor 14 is intercepted by the person 4 to be inspected laid on a top board 5 and the position (length) of the person 4 to be inspected is detected to be sent to a second signal conversion means 15. Signals of the signal conversion means 13 and 15 undergo a signal processing with a computer system 17 and the volume of the person 4 to be inspected for a transmitting/ receiving coil 7 is determined to be transmitted to a controller 18 to output energy of the optimum irradiation pulse which is sent to the transmitting/ receiving coil 7.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an MR imaging apparatus, and more particularly to an MR imaging apparatus equipped with a measurement function suitable for measuring individual differences among subjects.

0002

[Prior Art] Conventional MR imaging devices do not have information regarding individual differences (weight, height) of the subjects being measured, so it is difficult to distinguish, for example, between a small, fat person and a large, thin person. First, an irradiation pulse was applied to obtain a signal for image acquisition at a nearly constant value. For this reason, the size of the coil that transmits and receives signals is constant, so for obese people, the volume that fits inside the coil increases, resulting in insufficient energy for the irradiation pulse, and for thin people, conversely, the volume that occupies inside the coil decreases. Therefore, the energy of the irradiation pulse became excessive, and an appropriate image signal could not be obtained in either case, resulting in an image with a low S/N ratio.

Therefore, in order to compensate for the above-mentioned drawbacks, as a method to obtain an appropriate irradiation pulse, irradiation pulses of various energies are repeatedly applied in preprocessing before measurement, and while checking the output, the optimum irradiation pulse energy is determined. Processes such as finding .

0004

[Problems to be Solved by the Invention] In the above-mentioned conventional technology, although the size of the coil used is constant, the volume of the coil of the subject to be measured is not constant. The method used was to repeatedly scan over and over again in the processing process to find the optimal pulse, but this method required a lot of time for preprocessing, had poor throughput, and There were problems such as the amount of time people were detained for longer than necessary.

[0005] The purpose of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide an MR imaging device with a measurement function that automatically measures the volume of each subject, easily finds the optimal irradiation pulse for the probe, and improves throughput.

[0006]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a top plate and a table frame of a bed for a patient on which a patient is placed and transported to an air core where a static magnetic field is formed. The hydraulic cylinder of the hydraulic drive system for raising and lowering the body is equipped with a pressure sensor that detects the pressure, and transmits the pressure change due to the subject's weight to the first signal conversion means that converts it into an electrical signal. Multiple optical sensors are installed on the table frame of the bed to detect the position based on the height of the patient.
The subject lying on the top board cuts off the light from this optical sensor and transmits the optical signal to a second signal conversion means that converts it into an electrical signal, and further transmits it to a computer system that processes these signals. The data on weight and height, which are individual differences between examinees, is processed to determine the volume of the examinee's coil, which is then transmitted to the control device that controls the device, so that it outputs the optimal irradiation pulse energy. This system is designed to control and display data based on individual differences on a display.

[0007]

[Operation] When the subject gets on the top of the bed, the body weight, which is an individual difference between the subjects, becomes a pressure change in the hydraulic cylinder for raising the bed, and is transmitted to the pressure sensor. The pressure change caused by the pressure sensor is converted into an electrical signal by the first signal conversion means, and the signal is transmitted to a computer system that processes the signal.

[0008] Another individual difference in height is that when the subject lies on the top of the bed, the light from the optical sensor attached to the table frame that guides the top is cut, and the signal is This signal is converted into an electrical signal by the second signal conversion means, and is transmitted to the computer system that processes this signal to calculate the individual differences in weight and height of the subject. The data is processed as data and further transmitted as a volume to the coil of the subject to a control device that controls the device, so that the optimal irradiation pulse energy is selected and output. Furthermore, data based on individual differences can be displayed on the display of the operator's console, so that the condition of the subject can be managed.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of an MR imaging apparatus which is an embodiment of the present invention.

FIG. 2 shows an example of M
FIG. 3 is a side view of the bed of the R imaging device.

In FIG. 1, a superconducting magnet 1 forms an axial static magnetic field in its air core 2. As shown in FIG. At the top of the bed 3, a top plate 5 on which a subject 4 can be placed and transferred to the air center 2 is provided, which can be slid freely, together with a table frame 6 that guides the top plate 5. A transmitting/receiving coil 7 is installed on the top plate 5, and the subject 4 is placed inside the transmitting/receiving coil 7.
For example, the part to be measured of the subject 4 is introduced into the air core part 2 of the superconducting magnet 1 by sliding with the top plate 5 with the chest or abdomen inserted, and transmits and receives signals based on nuclear magnetic resonance. By doing so, a tomographic image can be obtained.

The table frame 6 of the bed 3 has a mechanism that moves up and down to make it easier for the patient 4 to get on and off the bed. The hydraulic cylinder 9 is provided with a hydraulic cylinder 9, a hydraulic pump 10, and a solenoid valve 11 to detect pressure changes. The pressure change due to the body weight of the person is detected and the signal of the pressure change is sent to the first signal conversion means 13 which converts the signal into an electrical signal. Further, a plurality of optical sensors 14 are provided on the table frame 6, and when the examinee 4 lies on the top plate 5, the light from the optical sensors 14 is cut off, and the position of the examinee 4 ( height) is detected. Furthermore, the signal obtained by cutting off the light from the optical sensor 14 is sent to a second signal converting means 15 that converts the changed signal into an electrical signal. Furthermore, the signals from these first and second signal converting means 13 and 15 are processed by a computer system 17 in the operator's console 16, and data on weight and height, which are individual differences of the subject 4, are processed. to determine the volume of the subject 4 relative to the transmitting/receiving coil 7, transmitting it to the control device 18 that controls the device, and controlling it to output the optimal irradiation pulse energy to be sent to the transmitting/receiving coil 7. is now possible. A display 19 within the console 16 displays data on weight and height based on individual differences, as well as optimal irradiation energy. According to this embodiment, there is no need for the subject 4 to measure his or her own weight and height before the measurement (especially for patients brought in due to an accident, etc., their weight and height are often unknown).
. In addition, there is no need to apply irradiation pulses of various energies to the transmitting/receiving coil 7 many times as pre-processing for measurement on the subject 4, and find the optimal irradiation pulse energy while checking the output. 4, the measurement time is shortened, throughput is significantly improved, and high-quality images can be easily obtained.

[0014]

[Effects of the Invention] According to the present invention, the following effects can be achieved.

1. Data on individual differences (weight, height) between test subjects is automatically and realistically measured and processed, so the volume of the test subject's coil is automatically processed,
Since the optimum irradiation pulse energy is applied, the optimum image signal is always obtained and the best image can be easily obtained.

2. To find the appropriate irradiation pulse,
Unlike conventional methods, it is not necessary to apply irradiation pulses of various energies many times in the pre-processing process and find the optimal irradiation pulse energy while checking the output, so measurement time is significantly shortened and it is possible to This also improves the throughput of human measurements.

3. Data on individual differences (weight, height) of the examinee is automatically measured and displayed and stored and managed in the computer, so there is no need to take measurements in advance, and the clinical information of the examinee increases, making it easier to use in clinical medicine. It will also be effective.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an MR imaging apparatus with a measurement function showing an embodiment of the present invention.

FIG. 2 is a side view showing a bed section of an MR imaging apparatus with a measuring instrument showing an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1... Superconducting magnet, 2... Air core, 3... Bed, 4... Subject, 5... Top plate, 6... Table frame, 7... Transmitting/receiving coil, 8...
X frame, 9...hydraulic cylinder, 10...hydraulic pump,
DESCRIPTION OF SYMBOLS 11... Solenoid valves, 12... Pressure sensor, 13... First signal conversion means, 14... Optical sensor, 15... Second signal conversion means, 16... Operator console, 17... Computer system, 1
8...Control device, 19...Display device.

Claims (1)

[Claims] Claim 1: MR in which a subject is introduced into an air core where a static magnetic field is generated by a static magnetic field generating means installed in a radio shielded room, and a tomographic plane of the subject is imaged by a magnetic resonance phenomenon. In an imaging apparatus, a top plate of a patient bed on which a patient is placed and transferred to an air core where a static magnetic field is formed, a table frame that guides the top plate, and an X that restricts vertical movement of the table frame. a frame, a hydraulic cylinder and a hydraulic pump for raising and lowering the table frame, a solenoid valve, a pressure sensor that detects the pressure of the hydraulic cylinder, and a first signal conversion means that converts the pressure change into an electrical signal; a plurality of optical sensors located on the table frame and detecting the position of the subject on the top plate; a second signal conversion means for converting optical signals from the optical sensors into electrical signals; MR imaging with a measurement function characterized by comprising: a computer system that processes a signal based on a signal conversion means; a control device that controls the device based on the processed signal; and a display that displays the signal. Device.