JPH0698885A - Radiation tomography equipment - Google Patents

Abstract

PURPOSE:To provide a radiation tomographic apparatus which enables the shortening of preparation time prior to scanning and is suitable for group health checking of a large number of people. CONSTITUTION:A radiation tomographic apparatus is arranged as opposed to a detector with respect to an X-ray source 3 through a photographing area while the X-ray source 3 and the detector 4 are kept free to move along a specified scanning surface maintaining the arrangement thereof intact. A gantry 1 is included to collect multi-way projection data with respect to a tomographic surface coinciding with a scanning surface of a specimen set within a photographing area and a gantry support mechanism 5 to support the gantry 1 in such a manner that the scanning surface becomes almost horizontal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation tomography apparatus which obtains a tomographic image by collecting multidirectional projection data on a tomographic surface of a subject and subjecting this data to reconstruction processing.

[0002]

2. Description of the Related Art Conventionally, an X-ray computed tomography (hereinafter referred to as "X-ray CT") is one of the radiation tomography apparatuses of this type.
There is a device called. This X-ray CT mainly includes a gantry that holds an X-ray source and an X-ray detector that rotate while facing each other across the imaging region, and a bed that sends the subject to the imaging region while resting in the lying position. As a structure
By repeating X-ray bombardment and detection at predetermined angles while rotating the X-ray source and the X-ray detector, multi-directional projection data on the tomographic plane of the subject is collected, and the multi-directional projection data is collected. Is subjected to a predetermined reconstruction process to calculate CT values at multiple points, and the CT values are two-dimensionally arranged to obtain a tomographic image.

A scan for actually collecting projection data in multiple directions is started after the following preparatory work. That is, it is an operation of fixing the subject to a predetermined position on the bed top and a position aligning work of sliding the top to align the inspection site of the subject with the scan plane. These preparations usually take a few minutes. On the other hand, the actual scan time required for data collection is several tens of seconds even in the multi-slice scan. Therefore, most of the time required for one examination is taken in the preparation time before scanning, and it has been imposed on the development of future radiation tomography apparatuses to shorten the preparation time as much as possible and improve the patient throughput. It was one of the important issues.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in order to cope with the above-mentioned circumstances, and its purpose is to shorten the pre-scan preparation time and to use it for a so-called group medical examination for a large number of people. Another object is to provide a suitable radiation tomography apparatus.

[0005]

In a radiation tomography apparatus according to the present invention, a radiation detector is arranged to face a radiation source via an imaging region, and these radiation sources are arranged along a predetermined scan plane while keeping this arrangement. And a radiation detector movably held, and a collection mechanism that collects projection data in multiple directions on a tomographic plane that matches the scan plane of the subject set in the imaging area, and that the scan plane is approximately horizontal. And a supporting mechanism for supporting the collecting mechanism.

[0006]

Since the radiation tomography apparatus according to the present invention has a substantially horizontal scan plane, it is possible to collect projection data in multiple directions while the subject is in a standing posture.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing the external appearance of this embodiment, and FIG. 2 is a block diagram of this embodiment.

If the gantry 1 is the R / R type third generation X-ray CT, the X-ray tube 3 for irradiating the fan beam X-rays and a plurality of X-ray detecting elements are arranged in a spread width of the fan beam X-rays. Accordingly, the detectors 4 arranged in parallel with each other are arranged so as to face each other across the imaging region, and a rotation mechanism for rotating around a predetermined scan plane while maintaining this positional relationship is provided. An opening 2 is provided at a substantially central portion for accommodating P, and is a device for collecting multidirectional projection data on a tomographic plane that coincides with the scan plane of the subject P accommodated in the opening 2. .

In this embodiment, the gantry 1 is supported by a gantry support mechanism 5 via an arm 6 which is movable in the vertical direction so that its tomographic plane is substantially horizontal. Then, when the subject P holds the positioning pole 9 and stands in a standing position, the positioning stand 7 is erected and has a positioning pole 9 provided with a U-shaped shoulder holder 8 at the tip. It is arranged so as to enter the opening 2 of No. 1.

Numeral 10 indicates expansion / contraction of the positioning pole 8,
A console (operation console) that concentrates all the operations necessary for imaging, such as exposure conditions such as tube voltage and tube current, rotation speeds of the X-ray tube 3 and detector 4, selection of the inspection site, and so on.
Is a monitor for displaying a reconstructed image (tomographic image) and the like.

In FIG. 2, the scan controller 12
Is a control center for executing the scan,
Based on the exposure conditions and the rotation speed input from the console 10, the rotation speed of the X-ray source 3 and the detector 4 by the rotation mechanism 13 and the DC high voltage are generated and applied to the cathode and the anode of the X-ray tube X. X-ray controller 14 for irradiating rays
Of the shoulder holder 8 detected by the holder height detection device 16 and the inspection from the console 10 while comprehensively controlling the output level and the output timing of the detector 4, the collection timing of the data collection unit 15 that collects the output of the detector 4, and the like. Gantry 1 travel range (scan range) based on region and
Is determined and the movement of the arm 6 of the gantry support mechanism 5 is controlled based on this.

The reconstruction processing device 17 receives the output from the detector 4 via the data collection unit 16 and provides the output (multidirectional projection data) for reconstruction processing such as the successive approximation method or Fourier calculation method. Thus, the CT values of multiple points are calculated and output to the display device 18 including the monitor 11. Next, the operation of the main X-ray CT having the above configuration will be described.

As a preparatory work before the start of scanning, the console 10 is used to set information necessary for imaging such as exposure conditions, rotation speed, examination site (here, lung). This information is sent to the scan controller 12 where it waits for a scan start instruction.

In this X-ray CT, as shown in FIG. 3, the subject P holds the positioning pole 9 of the positioning stand 7 and stands (stands up).
The subject P can be set at a position where it can be inserted into the opening 2 (inside the imaging region). Then, the positioning pole 9 is expanded / contracted to adjust the shoulder holder 8 to the shoulder portion of the subject P, and the subject P is fixed.

At this time, the height H1 of the shoulder of the subject P, that is, the height H1 of the shoulder holder 8 is determined by the holder height detecting device 16
Is detected by and is sent to the scan controller 12. The scan controller 12 normally has a shoulder height H
According to the distance H2 from the shoulder of the subject P to the lungs and the size C of the lungs, which are determined substantially according to 1, the scan range,
That is, lung height range {(H1-H2)-(H1-H2
-C)}, based on this range, the arm 6 of the gantry support mechanism 5 is controlled to move, the gantry 1 is set to the scan start position P1 or P2, and the lung, which is the examination site, is aligned with the scan plane. Complete.

When the pre-scan preparation work from setting and fixing of the subject P in the imaging region to alignment of the examination site and the scan surface is completed in this way, the main X-ray CT is controlled by the scan controller 12. Lower, rotation mechanism 13,
The X-ray controller 14 and the data acquisition unit 15 are operated on the console 10 according to the exposure conditions and rotation speeds set, and the arm 6 of the gantry support mechanism 5 is used to move the gantry 1 from the scan start position P1 (P2) to the scan end. While traveling continuously or intermittently at a predetermined speed to the position P2 (P1), multi-directional projection data on a plurality of tomographic planes relating to the lung is collected.

As described above, in this embodiment, since the gantry is supported by the gantry support mechanism so that the scan surface thereof is substantially horizontal, the subject can be set in the imaging area while standing. The subject can be set in the imaging area in a short time. Further, since the subject is fixed by the shoulder holder, it is possible to sufficiently suppress the artifact due to the body movement of the subject. Further, since the height of the gantry is automatically adjusted based on the height of the shoulder of the subject to align the inspection site and the scan surface, this alignment can be completed in a short time. Therefore, the time for pre-scan preparation work is shortened, the time required for one inspection is shortened,
Since the throughput of patients is improved, it is suitable to be used for an examination for a large number of people, so-called group examination.

The present invention is not limited to the above-mentioned embodiments, but can be modified in various ways. For example, in the above description, the subject P holds and holds the positioning pole 9 of the positioning stand 7 and presses the shoulder portion thereof with the shoulder holder 8 to set or fix the subject P in the imaging region. However, Fig. 4 (a), (b)
Positioning pole 9 and shoulder holder 8 as shown in
The subject P may be supported from the back side by moving the shoulder holder 8 along the positioning pole 9 as shown in FIG. Those that do may be adopted. In addition, the gantry support mechanism that supports the gantry 1 is
As long as the scan surface is supported substantially horizontally, for example, as shown in FIG. 5A, the gantry 1 may be hung from the ceiling T by an extendable arm 19. As shown in b), the gantry 1 may be supported by the arm 19 which is extendable from the floor surface F.

[0019]

As described above, in the radiation tomography apparatus according to the present invention, the radiation detector is arranged so as to face the radiation source through the imaging region, and these radiations are arranged along a predetermined scan plane while keeping this arrangement. A collection mechanism that movably holds the radiation source and the radiation detector and collects multi-directional projection data on a tomographic plane that matches the scan plane of the subject set in the imaging region Since it has a structure that is supported horizontally, it is possible to collect projection data in multiple directions while the subject is in a standing posture, and therefore, it is possible to shorten the setting of the subject in the imaging area. Therefore, the patient throughput can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing an appearance of an X-ray CT according to an embodiment of the present invention.

FIG. 2 is a block diagram of an X-ray CT according to an embodiment of the present invention.

FIG. 3 is a side view of a positioning pole and a subject supported by the positioning pole.

FIG. 4 is a diagram showing another example of the positioning pole shown in FIG.

5 is a view showing another example of the gantry support mechanism shown in FIG.

[Explanation of symbols]

1 ... Gantry, 2 ... Aperture, 3 ... X-ray source, 4 ... Detector,
5 ... Gantry support mechanism, 6 ... Arm, 7 ... Positioning stand, 8 ... Shoulder holder, 9 ... Positioning pole, 10 ... Console, 11 ... Monitor, 12 ... Scan controller, 13 ... Rotation mechanism, 14 ... X-ray controller, 15 ... data collection unit, 16 ... holder height detection device, 17 ... reconstruction processing device, 18 ... display device.

Claims (3)

[Claims] 1. A radiation detector is arranged to face a radiation source via an imaging region, and while keeping this arrangement, the radiation source and the radiation detector are movably held along a predetermined scan plane, A collection mechanism that collects multi-directional projection data on a tomographic plane that matches the scan plane of the subject set in the imaging region, and a support mechanism that supports the collection mechanism so that the scan plane is substantially horizontal. A radiation tomography apparatus comprising: 2. The radiation tomography apparatus according to claim 1, wherein the support mechanism supports the collection mechanism so as to be movable in a direction orthogonal to the scan plane. 3. The radiation tomography apparatus according to claim 1, further comprising a pole arranged in the imaging area.