JPH0315449A - Mobile medical examination vehicle - Google Patents

Abstract

PURPOSE:To contrive the improvement of medical examination processing ability and the facilitation of radiographing work by emitting residual radiation energy on a recording unit prior to picture recording thereof, after a picture is read in a picture read part, and relatively repeating the movement in the picture read part in relation to the recording unit on a supporter. CONSTITUTION:When reading of a picture is ended, further the surface total unit of an accumulative fluorescent material layer 2 is cleaned by a cleaning roller 11, and then a stage, on which an optical deflector 7 and an optical detector 8 or the like are mounted, is returned to a standby position dislocated to a place upper then a recording member 3. Thereafter, an eliminating light source 10 is lighted for a predetermined time, and after reading operation in the accumulative fluorescent material layer 2, radiation energy caused by radiant rays or environmental radiant rays emitted from a radio isotope, e.g. <266>Ra and <40>K or the like in residual radiation energy and in an accumulative fluorescent material is emitted. Accordingly, post read picture, formed in the accumulative fluorescent material layer 2 by this radiation picture recording, is eliminated, and the recording member 3 is again used for radiation picture recording.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a mobile medical examination vehicle loaded with a radiographic apparatus and moved to various locations for medical examinations.

When certain types of phosphors are irradiated with radiation (X-rays, alpha rays, beta rays, gamma rays, ultraviolet rays, etc.), a portion of the energy of this radiation is stored in the phosphor and is then released into the phosphor. When irradiated with excitation light such as visible light, the phosphor exhibits stimulated luminescence depending on the accumulated energy. A phosphor exhibiting such properties is called a stimulable phosphor.

(Prior art) Using this stimulable phosphor, radiation image information of the human body, etc. is recorded on a sheet of stimulable phosphor, and this is scanned with excitation light to cause stimulated luminescence. A method has been proposed in which an image signal is obtained by electrically reading out the emitted light, and this image signal is processed to obtain an image suitable for diagnosis. (For example, JP-A-55-12429, JP-A No. 5B-
No. 11395, No. 55-163472, No. 56-10
(No. 4G45, No. 55-116340, etc.) This final image may be reproduced as a hard copy, or
It may also be reproduced on a CRT. In any case, in such a radiographic image information recording and reproducing method, a stimulable phosphor sheet (strictly speaking, this can take various forms such as a panel or a drum, but it is generally called (hereinafter referred to as a "sheet") does not ultimately record image information, but temporarily carries image information in order to provide the image to the final recording medium as described above, so this accumulation The fluorescent phosphor sheet may be used repeatedly, and such repeated use is extremely economical.

In order to reuse the stimulable phosphor sheet as described above, the radiation energy accumulated in the stimulable phosphor sheet after the stimulated luminescence light is read is used, for example, in Japanese Patent Laid-Open No. 56-113
92, No. 513-12599, the radiation image can be erased, and the stimulable phosphor sheet can be used again for recording radiation images.

The radiation image information recording and reproducing method using a storage phosphor in this manner is particularly effective when used for medical diagnosis.

In other words, this method can obtain radiation image information suitable for the diagnostic structure by performing various signal processing on electrical signals, and can also reduce radiation exposure by adjusting the reading gain of the photodetector during photoelectric conversion. It has great advantages over conventional radiographic methods that use silver salt emulsions, such as the ability to significantly reduce the amount of silver salt emulsions.

(Problem to be Solved by the Invention) Therefore, medical examinations using this radiographic image information recording and reproducing method can be performed not only in medical institutions such as hospitals, but also in mobile examination vehicles loaded with equipment, such as conventional X-ray indirect radiography vehicles. It is hoped that this will be implemented in various locations. However, in this radiographic image information recording and reproducing method, the radiographic work is complicated because each large stimulable phosphor sheet is used to record radiographic image information. In order to examine a patient, this large sheet must be loaded onto a mobile examination vehicle and carried around, which naturally limits the examination processing capacity of the mobile examination vehicle.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a mobile medical examination vehicle in which the medical examination processing capacity by the radiation image information recording and reproducing method described above is significantly improved, and furthermore, radiography work is easy. Furthermore, it is an object of the present invention to provide a mobile medical examination vehicle which has improved examination processing capacity as described above and which also makes it possible to immediately produce diagnostic results at the examination site.

(Means for Solving the Problems) The mobile medical examination vehicle of the present invention has a recording body made of a stimulable phosphor layer fixed on a fixed support, and radiation having image information is emitted from one side of the recording body. An image reading device comprising an image recording unit that accumulates and records radiation images by irradiation, and a photoelectric reading device that scans the opposite side of the recording body with excitation light and reads the emitted stimulated luminescence light to obtain an image signal. a part, an erasing means for emitting radioactive energy remaining in the recording body after reading, and repeating the image reading part (and the image erasing part) relative to the recording body on the support body. A radiographic image information recording/reading device comprising moving means is mounted on a vehicle such as a bus.

(Function) In the radiation image information recording/reading device having the above structure, since the recording medium on the fixed support is repeatedly reused while the radiation image is erased in the mobile examination vehicle, one image is recorded for each imaging session. There is no need to handle additional stimulable phosphor sheets, and screening throughput can be increased virtually unlimitedly.

The image signal obtained by the reading means is transmitted in real time to a reproduction device (for example, a hard copy production device or a display device such as a CRT) installed in a hospital etc. using a telephone line or wireless, and a specialist can perform the reproduction. It is also possible to observe the images and report the diagnostic results back to the mobile examination vehicle. It is also possible, of course, to transmit the image signal to a hospital, etc., record this image signal once on a recording medium such as a magnetic tape, magnetic disk, or optical disk, and later obtain a reproduced image for diagnosis. . By transmitting the image signal outside the medical examination vehicle in this way and recording or reproducing the image signal at a hospital or the like, the number of devices loaded on the mobile medical examination vehicle can be reduced.

However, when using a car with a large loading capacity, a recording device using the recording medium as described above,
Of course, it is also possible to load a small-sized reproduction device into a medical examination vehicle. By loading the reproducing device into a medical examination vehicle and having a specialist accompany the patient, it is naturally possible to immediately notify the patient of the diagnosis result at the radiography site. Furthermore, since the recording medium described above can be made compact and record an extremely large amount of information, even if an image signal recording device using this type of recording medium is loaded on a medical examination vehicle, it will not be possible to use a large-sized (e.g. Conventional X
Compared to storing radiographic images on each stimulable phosphor sheet (like the size of a ray film cassette) and then transporting them to a medical institution, the processing capacity for medical examinations relative to the weight of the loading device can be significantly increased. .

In the present invention, a storage phosphor is a material that, when irradiated with radiation (X-rays, α-rays, β-rays, γ-rays, ultraviolet rays, etc.), accumulates a portion of this radiation energy internally, and When irradiated with excitation light such as visible light, it has the property of emitting stimulated luminescence light in an amount corresponding to the accumulated energy.

In the present invention, it is preferable that the wavelength range of the excitation light and the wavelength range of the stimulated luminescent light do not overlap in order to improve the S/N ratio, and an excitation light source and a stimulable fluorescent light that satisfy such a relationship are preferably used. It is preferable to choose a light body. Specifically, it is desirable that the excitation light wavelength be 450 to 700 nm and the stimulated emission light wavelength be 300 to 500 nII+.

In this way, it emits stimulated luminescence light of 300 to 500 nm,
Examples of stimulable phosphors that can be preferably used in the present invention include rare earth element-activated alkaline earth metal fluorohalide phosphors [specifically, JP-A No. 55-12143
(Bat-X-y+Mgx, C
ay) FX: aEu” (where X is CI! and Be
at least one of
XlO-2), (Ba + -, M" - ) FX:y described in Japanese Patent Application Laid-open No. 1983-12l45
A (However, Mll is at least one of Mg, Ca, Sr, Zn and Cd, X is at least one of CJ2, Br and I, A is Eu, Tb, Ce, Tm, D
At least one of y, Pr, Ho, Nd, Yb and Er, X is 0≦X≦0.8, y is O≦y≦0.2
ZnS:Cu,PbS BaO-xAJ! described in JP-A-55-12142! z
o. 3:Eu (however, 0.8≦X≦10) and M"O-xSi 02:A (however, M" is M
g, Ca, Sr, Zn, Cd or Ba, A is C
e, Tb, Eu, Tm, Pb, TIB1 or Mn, and X is 0.5≦X≦25); and JP-A-55
LnOX:xA (where Ln is at least one of La, Y, Gd, and Lu) described in Publication No.-12144
X is Cf! and at least one of Br, A
is at least one of Ce and Tb, and Q<x
<0.1); and the like. Among these, rare earth element-activated alkaline earth metal fluorohalide phosphors are preferred, and among these, barium fluorohalides shown as specific examples are particularly preferred because of their excellent stimulable luminescence.

Furthermore, barium fluorohalide phosphor was developed in Japanese Unexamined Patent Publication No. 56
-2385 Publication, 5B-2386 Publication to which metal fluoride is added, or Japanese Patent Application No. 1983-
The addition of at least one of a metal chloride, a metal bromide, and a metal iodide as disclosed in No. 150873 is preferable because the stimulated luminescence is further improved.

Further, as disclosed in Japanese Patent Application Laid-Open No. 55-163500, when the phosphor layer of a stimulable phosphor plate prepared using the above-mentioned stimulable phosphor is colored with a pigment or dye,
This is preferable because the sharpness of the finally obtained image is improved.

11 12 (Example) Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a first embodiment of the invention. The mobile medical examination vehicle 50 of this embodiment is, for example, a motor vehicle 40 such as a bus.
A radiographic image information recording/reading device 20 and an image signal recording device 30, which will be described later, are mounted on the holder.

In the mobile medical examination vehicle 50 of this embodiment, a stimulable phosphor layer 2 is provided on the surface of a fixed support 1 made of a plate-shaped radiation-transparent material on a radiation image information recording/reading device 20 loaded on a car 40. A stacked recording section shrine 3 is used. A radiation source 4 is located at a position facing the support side surface of the recording member 3.
is provided. This radiation source 4 is, for example, an X-ray source, and transmits a transmitted radiation image of a subject 5 disposed between this radiation source 4 and the recording section shrine 3 through a support 1 made of a radiation-transparent material through a stimulable phosphor layer. Project onto 2. The projected radiation image is accumulated and recorded on the stimulable phosphor layer 2. At a position facing the phosphor side surface of the recording part shrine 3, there is an excitation light source 6 that emits excitation light such as a laser beam, and an excitation light source 6 that scans the excitation light emitted from the excitation light source 6 in the width direction of the recording member 3, for example. A light deflector 7 such as a galvanometer mirror, a photodetector 8 that reads the stimulated luminescent light emitted from the stimulable phosphor layer 2 excited by the excitation light, and a light that guides the stimulated luminescent light to the photodetector 8. A transmission means 9 is provided mounted on a common stage (not shown). The photodetector 8 is, for example.
For example, it is a head-on type photomultiplier tube, a channel plate for photoelectron amplification, or the like, and photoelectrically detects the stimulated luminescence light introduced by the light transmission means 9.

Regarding the material, structure, or how to use the light transmission means 9, see Japanese Patent Application Laid-open Nos. 55-87970, 5B-11397, 5B-11396, 5B-11394, and 5.
The methods and methods disclosed in No. B-11398, No. 5B-1.1395, etc. can be used as they are.

Further, at a position facing the phosphor side surface of the recording member 3,
An erasing light source IO is provided, and a cylindrical cleaning roller 11 is mounted on the stage described above, which is rotated in the direction of the arrow in the figure by a drive device (not shown). The erasing light source 10 emits radiation energy accumulated in the stimulable phosphor layer 2 by irradiating the stimulable phosphor layer 2 with light included in the excitation wavelength range of the phosphor. For example, a tungsten lamp, a halogen lamp, an infrared lamp, a laser light source, etc. as shown in Japanese Patent Application Laid-Open No. 56-11392, as mentioned above, can be arbitrarily selected and used. Note that the radiation energy stored in the stimulable phosphor layer 2 can also be released by heating the stimulable phosphor, as shown in Japanese Patent Laid-Open No. 56-12599, for example. , the erasing light source 10 may be replaced with a heating means. When the cleaning roller 1l contacts the surface of the recording member 3 and moves while rotating on the recording member 3,
This is to remove dust and dirt adhering to the surface of the stimulable phosphor layer 2 of the recording section 3 from the surface of the phosphor, and if necessary, remove the dust and dirt using electrostatic phenomenon. It may also be formed into something that can be adsorbed.

The operation of the apparatus of this embodiment having the above structure will be explained below. After the subject 5 is placed between the recording member 3 and the radiation source 4, when the radiation source 4 is turned on, a transmitted radiation image of the subject 5 is accumulated and recorded on the stimulable phosphor layer 2 of the recording shrine 3. be done. After the recording of the radiation image is completed, the excitation light source 6 is turned on, and the stimulable phosphor layer 2 is scanned by the excitation light emitted from the excitation light source 6. The excitation light is scanned in the width direction of the recording member 3 by the optical deflector 7 (main scanning), and a stage fixes the excitation light source 6, the optical deflector 7, the photodetector 8, the optical transmission means 9, and the cleaning roller 1l. By moving from the top to the bottom in the figure, the recording member 3 is scanned in the vertical direction (sub-scanning). A stage that moves as described above can be easily formed using a known linear movement mechanism. When irradiated with the excitation light, the stimulable phosphor layer 2 emits stimulated light according to the image information stored and recorded. This stimulated luminescent light is input to the photodetector 8 via the light transmission means 9 and photoelectrically converted, and the photodetector 8 outputs an electrical image signal corresponding to the image information. When the stage is moved from above to below for the above-mentioned sub-scanning, the cleaning roller 1l mounted on this stage is rotated.

This moving cleaning roller 11 sweeps the surface of the stimulable phosphor layer 2, removing fine dirt and dust from the surface. When the image reading is completed and the entire surface of the stimulable phosphor layer 2 is cleaned, the stage equipped with the optical deflector 7, the optical detector 8, etc. is moved to the recording member 3.
It is returned to the standby position upward in the figure. after that,
When the erasing light source IO is turned on for a predetermined period of time, the radiation energy remaining in the stimulable phosphor layer 2 after the reading operation and the trace amount of 2 6 6 R mixed in the stimulable phosphor layer are removed.
Radiation energy caused by radiation emitted from radioactive isotopes such as a and 40K or by environmental radiation is emitted. Therefore, the radiation image formed on the stimulable phosphor layer 2 after reading is erased by this radiation image recording, and if the device has not been used for a long time, the storage Radiation energy from radioactive isotopes or environmental radiation accumulated in the fluorescent phosphor layer 2 is also released, returning it to a reusable state. The recording member 3 that has been cleaned and image erased as described above is used again for recording radiographic images.

The electrical image signal output from the photodetector 8 is recorded on an image signal recording device 30. Various known devices can be used as the image signal recording device 30. For example, a device that digitizes the signal and records it on a high-density recording medium such as a magnetic tape, a magnetic disk, or an optical disk is preferable. The identification number of the subject is recorded on the recording medium of the image signal recording device 30 in association with the image signal, and the subject is brought to a medical institution such as a hospital by the mobile examination vehicle 50. In this medical institution, the recording medium is loaded onto a playback device to obtain a playback image on a hard copy or CRT display. The specialist makes a diagnosis based on this reproduced image and notifies each subject of the findings.

As already mentioned, instead of the image signal recording device 30, a transmission device for transmitting electrical image signals to a remote location by, for example, a telephone line or wirelessly is mounted on the automobile 40, and the transmission device is installed in a hospital or the like far from the radiation imaging site. The image signal may be recorded, or a reproduced image may be immediately obtained from this image signal and the diagnosis result may be transmitted back to the mobile examination vehicle 50. Furthermore, a small reproducing device such as a CRT display device may be loaded on the mobile examination vehicle 50 so that the reproduced image can be immediately observed at the radiography site.

In addition, since there is no need to handle the sheet-like stimulable phosphor for each radiographing, the radiographing work becomes very easy.

It should be noted that prior to reproducing a radiation image, it is possible to perform signal processing on the image signal to enhance the image, change the contrast, etc., and in order to obtain a radiation image with excellent diagnostic performance, such It is desirable to perform appropriate signal processing. Desirable signal processing used in the present invention includes Japanese Patent Application Laid-open Nos. 55-87970 and 5 [i-11
No. 038, JP-A-56-75137, JP-A No. 5B-751
No. 39, No. 5B-75141, No. 5B-104845
Frequency processing disclosed in JP-A-55-116, etc.
No. 339, No. 55-118340, No. 55-8874
Examples include gradation processing disclosed in No. 0 and the like.

As mentioned above, since the device of the present invention does not carry out the transport of a stimulable phosphor, the mechanism is extremely simple and can be easily designed and manufactured. Furthermore, since one recording medium is used repeatedly, sheet management is easy and uniform reproduced images can be obtained.

In the first embodiment described above, sub-scanning for reading radiation images is performed by moving the excitation light irradiation system and the stimulation light reading system with respect to the fixed recording member 3; On the other hand, the excitation light irradiation system and the stimulated light reading system may be fixed to the image reading zone, and sub-scanning may be performed by moving the recording medium. In the second embodiment shown in FIG. 2, the sub-scanning method in which the recording medium is moved as described above is used. In the mobile medical examination vehicle 150 of the second embodiment, the radiation image information recording/reading device 120 loaded on the automobile 140 has a support made of radiolucent material, as in the first embodiment. A recording member 103 having a stimulable phosphor layer 102 laminated on top of the recording member 101 is used. and the same radiation source Io4 and excitation light source 106 as in the first embodiment.
, optical deflector 107, photodetector l08, optical transmission means 109
, an erasing light source l10, and a cleaning roller txt are provided. Both side edges of the recording member 103 are formed by grooves 11 at the center of two rails n2 extending in the vertical direction in the figure.
3, and the recording section shrine 103 is movable in the vertical direction in the figure along this rail 112. The recording section shrine 1o3 is moved in the vertical direction in the figure by a linear moving device (not shown) such as a rack and pinion mechanism.

Radiation lfl. After a transmitted radiation image of the subject 105 is recorded by l04, excitation light is irradiated and the radiation image is read. At this time, the main scanning is performed by the optical deflector 107 as in the second embodiment, but the sub-scanning is performed by the linear moving device to move the recording member 10
3 from the bottom to the top in the figure. When the recording member 103 is moved, the rotating cleaning roller 111 comes into contact with the recording member 103, and the recording member 103 is cleaned. After the image reading is completed and the recording member 103 is returned downward, the erasing light source 1
10 is turned on, and the radiation image that has been read is erased.

In the second embodiment described above, the stimulable phosphor is moved for sub-scanning of image reading, but the movement of the stimulable phosphor is caused by moving the plate-shaped support. Of course, this type of moving mechanism can be constructed more easily than a mechanism that transports sheet-shaped stimulable phosphors one by one.

In the first and second embodiments described above, the stimulable phosphor is laminated on a support made of a radiation transparent material,
Although it is intended to be placed on the opposite side of the support from the radiation source, it is not necessary for the recording body to be formed in this way.

For example, when a stimulable phosphor plate is laminated on a support made of a radiation-opaque material and is placed facing a radiation source, the excitation light irradiation system and photostimulation The reading system may be moved to the vicinity of the recording medium. Furthermore, if the support is transparent to excitation light and stimulated luminescence, a radiation source may be provided at a position facing the phosphor side surface, and a reading device may be placed at a position facing the support side surface. Needless to say.

In addition, the recording state or recording pattern of the radiation image information accumulated and recorded on the stimulable phosphor sheet is grasped before the reading operation, and the reading gain of the photoelectric reading means is set, the appropriate recording scale factor is determined, and the signal processing is performed. In order to obtain radiographic images with excellent diagnostic performance, it is preferable to set the conditions, and for this purpose, the recording state or recording pattern of radiographic image information is read with low excitation light energy (hereinafter referred to as ``pre-reading'') prior to the reading operation. ”.

) A method and apparatus for performing a reading operation (hereinafter referred to as "book reading") to obtain a radiation image used for diagnosis are disclosed in Japanese Patent Application Nos. 56-165111 and 5B-1654.
No. 12, No. 5B-165113, No. 5B-1 [i5L
This is proposed by No. L4 and No. 5B-165115. In the present invention, such pre-reading is also performed by separately providing a pre-reading reading section having a similar configuration upstream of the image reading section, or by using the image reading section for both pre-reading and main reading. can satisfy the request.

(Effects of the Invention) As explained above, the radiographic image information recording/reading device for a mobile medical examination vehicle according to the present invention uses only one recording medium repeatedly, so if the quality of the reproduced image deteriorates, It is only necessary to replace the recording medium in use with a new one, and quality control of the recording medium is extremely easy.

Furthermore, the mobile medical examination vehicle of the present invention has a fixed recording body that stores and records radiation image information that can be reused repeatedly within the vehicle, so handling of the recording body is no longer necessary, making the imaging work easier. Since there is no need to stack many large stimulable phosphor sheets, the medical examination throughput is extremely high.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a first embodiment of the present invention, and FIG. 2 is a schematic diagram showing a second embodiment of the present invention. 1, 101...Support 2, 102...Storable phosphor layer 3, 103...Recording member 4, 104...Radiation source 5, 105...Subject 6, 108...Excitation light source 7, 107... Light deflector 8, 108... Photodetector 9, 109... Light transmission means 10, 110... Erasing light source 20, ↓20... Radiation image information recording/reading device 30・
...Image signal recording device 40, 140...Car 50, 150...Mobile examination vehicle Fig. 25

Claims (1)

[Scope of Claims] 1) A fixed support; A recording body comprising a stimulable phosphor layer fixed on the support and capable of accumulatively recording at least one radiation image; An image viewed from one side of the recording body; an image recording unit that accumulates and records a radiation image on the recording medium by irradiating radiation that has information; an excitation light source that emits excitation light that scans the opposite surface of the recording medium on which the radiation image is accumulated and recorded; an image reading section having a photoelectric reading means for reading stimulated luminescence light emitted from the recording medium scanned by the excitation light to obtain an image signal; an erasing means for emitting residual radiation energy on the recording medium prior to image recording; and a means for repeatedly moving the image reading section relative to the recording medium on the support. A mobile medical examination vehicle that is equipped with a radiation image information recording and reading device. 2) A fixed support, a recording body fixed on this support and consisting of a stimulable phosphor layer that can store and record at least one radiation image, and irradiation of radiation having image information from one side of this recording body. An image recording section that accumulates and records a radiation image on this recording medium; an excitation light source that emits excitation light that scans the opposite side of the recording medium on which the radiation image is accumulated; an image reading section having a photoelectric reading means for reading stimulated luminescence light emitted from a recording medium to obtain an image signal; an image is recorded on the recording medium after the image is read in the image reading section; an erasing means for emitting residual radiation energy on the recording body prior to the recording, and a means for repeatedly moving the image reading section and the image erasing section relative to the recording body on the support. A mobile medical examination vehicle equipped with a radiation image information recording/reading device. 3) A fixed support, a recording body fixed on this support and consisting of a stimulable phosphor layer capable of storing and recording at least one radiation image, and irradiating radiation having image information from one side of this recording body. An image recording section that accumulates and records a radiation image on this recording medium; an excitation light source that emits excitation light that scans the opposite side of the recording medium on which the radiation image is accumulated; an image reading section having a photoelectric reading means for reading stimulated luminescence light emitted from a recording medium to obtain an image signal; an image is recorded on the recording medium after the image is read in the image reading section; radiation image information recording and reading comprising an erasing means for emitting residual radiation energy on the recording body prior to the recording, and a means for repeatedly moving the image reading section relative to the recording body on the support body. A mobile medical examination vehicle comprising: a device; and a reproduction device for reproducing a radiation image from the image signal.