JPS6185930A - X-ray tomographic apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an X-ray tomography apparatus that particularly takes into consideration the safety of a subject to be imaged.

[Technical background of the invention] In general, tomography equipment moves the X-ray tube focal point along a certain trajectory in order to obtain an aimed tomographic image inside the subject, while at the same time maintaining a certain relationship with the focal point of the X-ray tube. Move a fixed point on the film along a certain trajectory! The configuration is such that an arbitrary point on a plane that cuts through the object makes the relative speed between the film and the shadow projected onto the film surface zero. When performing such tomography, the X-ray irradiation field and the tomography 11i must be precisely positioned at the desired position of the subject. It is necessary to match the height of the shadow surface (hereinafter referred to as the height of the cut surface).

This positioning method will be explained with reference to FIG.

FIG. 4 is a schematic diagram of the X-ray tomographic imaging device viewed from the body axis direction, in which a top plate 3 on which a subject 2 is placed on a bed device 1 is supported so as to be movable in the direction of the arrow. . Next to the bed device 1, a connecting rod 5 with a rotating center machine groove 4 supported on a pedestal (not shown) is arranged, and an X-ray tube 6 and a radiation aperture 7 are connected to one end of the connecting rod 5 via a support arm. ,
Moreover, a Butsky device 8 containing an X-ray film is connected to the other end. Note that although this rotation center mechanism 4 is supported so as to be movable in the direction of arrow C, the bed device 1 may be moved in the direction of arrow B instead of moving this rotation center mechanism 4. With this configuration, the connecting rod swings in the vertical direction (direction perpendicular to the plane of FIG. 4) or in the horizontal direction with respect to the subject 2, centering on the rotation center mechanism 4.

First, to explain the positioning of the X-ray irradiation field, it is carried out by moving the top plate 3 on which the subject 2 is placed in the direction of the arrow and in the vertical direction, and adjusting the aperture 7 to an appropriate size. are doing. This is a method used in general X-ray diagnostic equipment.

Next, positioning of the height of the cut surface will be explained. By fixing a projector 9 to the rotation center mechanism 4 and projecting, for example, a cross-shaped beam of light onto the side surface of the subject 2, the current height of the cut surface can be visually observed. Thereafter, the cutting surface height is generally set by moving the top plate 3 in the direction of arrow B or the rotation center mechanism 4 in the direction of arrow C while checking the cross shape projected onto the subject 2. be.

However, in such a mechanism, the above-mentioned X
In order to widen the positioning range of the radiation field, especially the top plate 3
When the directional movement stroke is made larger in the direction of the arrow, the distance wiS between the top plate 3 and the tomographic mechanism 10 including the rotation center mechanism 4 and the connecting rod 5 becomes smaller, and the finger or arm of the subject 2 is pinched. It is very dangerous and dangerous. For this reason, it is conceivable to increase the distance S so that even when the top plate 3 comes closest to the fault mechanism 10, it will not pinch the subject 2.
This is undesirable because it increases the size of the entire tomography apparatus.

Another method for avoiding the above-mentioned danger is to attach a safety guard 11 having an appropriate length in the body axis direction to the side surface of the top plate 3 facing the fault mechanism, as shown in FIG. However, since it is necessary to limit the height of the safety guard 11 to such an extent that it does not block the light beam from the light projector 9 fixed to the rotation center mechanism 4, it has a major drawback in that it does not function as a safety guard.

[Object of the Invention] The present invention was made in view of the above circumstances, and an object of the present invention is to provide an X-ray tomographic imaging apparatus equipped with a safety guard that takes into account the safety of a subject.

[Summary of the Invention] In order to achieve the above-mentioned object, the present invention provides an X-ray layer imaging device that is disposed on the side of the subject and is equipped with a projector for positioning the cut-off height of the subject. The apparatus is characterized in that a light-transmissive guard member is disposed between the light projector and the subject.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. As shown in FIG. 1, a guard plate 12 is formed which has a box-shaped cross section and an appropriate length in the longitudinal direction of the bed.

A window portion 12a extending above the guard plate 12 is formed of a material through which light can pass. For example, a transparent acrylic plate may be formed so that its cross section is in the shape of a single letter, or the window portion 12 may be
Various implementations are possible, such as using different materials for a and the other parts.

Further, the length in the longitudinal direction preferably extends over the entire length of the top plate 3, but only the arm and leg portions of the subject 2 may be guarded. Furthermore, the height of the window portion 12a is preferably about 10 to 20 CI11. As shown in FIG. 2, the guard plate 12 formed in this manner
3 is fixed to the top plate 3, but it may be directly bonded to the top plate 3 if there are no problems with maintenance or maintenance.

With this configuration, when setting the caricature height of the subject 2, the light beam from the projector 9 passes through the window 12a of the guard plate 12 and is projected onto the subject. can be made sufficiently high. Therefore, the cutting surface height setting operation is not hindered in any way, and the finger or arm of the subject is not
There is no danger of it getting stuck in 1@10. In addition, since the danger to the subject can be completely eliminated, it is possible to reduce the distance S to approximately zero when the top plate 3 moves in the direction of the arrow and approaches the tomography mechanism 10, and the tomography apparatus The overall size can be reduced.

The present invention is not limited to the above embodiments, and can be implemented with various modifications. For example, it has been explained that the guard plate is fixed to the top plate, but as long as the guard plate moves along with the top plate, that is, if the relative velocity seen from the top plate is zero, the guard plate can be fixed to any member. The purpose can be achieved. Further, although it has been described that the transparent window portion of the guide plate covers the entire length in the longitudinal direction, only the area that can cover the movement range of the top plate and the floodlight may be made transparent and used as a window portion.

Furthermore, it goes without saying that the window portion is not limited to a completely transparent member, but may also be made of a translucent member, a mesh-like material having a relatively large individual opening, or the like.

[Effects of the Invention] According to the present invention described above, it is possible to provide an extremely excellent X-ray tomography apparatus that eliminates the danger to the subject and does not hinder the setting of the cutting surface height.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the guard plate according to the present invention, FIG. 2 is a view showing how the guard plate of FIG. 1 is used, and FIG. 3 is a view showing how the conventional guide plate is used. Figure 4 is X
FIG. 2 is a schematic diagram for explaining positioning in a line tomography apparatus. 2... Subject, 9... Emitter 12... Guard plate, 12a... Window, 13... Mounting screw M 1 Figure 2

Claims (1)

[Claims] In an X-ray tomography apparatus equipped with a floodlight disposed on the side of a subject for positioning the cut surface height of the subject, a light-transmissive guard member is disposed between the floodlight and the subject. An X-ray tomography device characterized by: