JPH0550386U - ECT device - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose is to obtain SPECT images with good image quality by collecting image data that is not affected by the absorption or scattering of radiation by the top plate. [Structure] The top plate 5 is provided with a cutout portion 7.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an ECT apparatus of a type in which a scintillation camera detector is rotated around a subject, and more particularly, to an improvement of an ECT bed.

[0002]

[Prior Art]

 This type of ECT device includes a bed equipped with a top plate for supporting a subject, at least one scintillation camera detector (hereinafter referred to as a detector), and a detector which holds this detector and is mounted on the top plate. It is composed of a stand that rotates about an axis parallel to the longitudinal axis, and rotates the detector around a subject located on the top plate on a plane that intersects the body axis. The detector collects image data in each direction of the subject and performs image reconstruction processing to obtain a SPECT image (transaxial image).

In the acquisition of the image data described above, the detector is normally rotated 360 ° around the subject (full scan). However, especially when obtaining a SPECT image of the heart, the data is not acquired at the time of data acquisition. The 180-degree acquisition method (half-scan method) that shortens the interval, that is, the range in which the detector rotates around the body axis of the subject to collect data is the subject in the supine position. In general, the right front 30 ° to the left rear 150 ° (RAO 30 ° to LPO 30 °) or the right front 45 ° to the left rear 135 ° (RAO 45 ° to LPO 45 °) is 180 °. It is used for.

[0004]

[Problems to be solved by the device]

 Even with the 180-degree acquisition method described above, the detector still needs to rotate from the front position to the back position of the subject. Although the top plate that supports the subject is formed of a material that absorbs little radiation (γ-rays), absorption and scattering of radiation due to this is unavoidable, and the effects of this absorption and scattering of radiation are The image quality of the SPECT image (particularly the image quality on the back side of the subject) is deteriorated by being reflected in the collected data at the back position of the subject by the detector. In addition, there is a problem that the detector cannot be brought close to the subject on the back side due to the intervention of the top plate, and the resolution cannot be improved.

The present invention has been made in view of these circumstances, and improves the contrast by eliminating the absorption and scattering of radiation by the top plate, and further brings the detector closer to the subject to improve the S / N ratio. The objective is to provide an ECT device that can obtain a high-quality SPECT image by increasing the resolution.

[0006]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention is characterized in that a cutout portion is provided on the side of the top plate of the bed in the ECT device.

[0007]

[Action]

 As described above, the top plate is provided with the notch, and the top plate in that part is cut away, so that the data collected at the back of the subject (below the top plate) of the detector is Since there is no influence of absorption and scattering of radiation by the plate and there is no top plate, the detector can be brought closer to the subject by the thickness of the top plate. As a result, the quality (contrast, resolution) of the SPECT image is improved.

[0008]

【Example】

 Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. 1 is a side view showing an embodiment, FIG. 2 is a plan view showing the structure of the bed shown in FIG. 1, and FIG. 3 is a view showing the positional relationship between the notch portion of the present invention, the subject, and the detector. FIG. 3 is a III-III view of FIG.

As shown in FIG. 1, the ECT device includes at least one scintillation camera detector (hereinafter referred to as a detector) 1 and a stand 2 that holds the detector 1 and rotates to perform the detection. The device 1 is rotated on a plane intersecting the body axis around the subject 6 located on the top plate 5 of the bed 4 fixed to the carriage 3, and the detector radiates from the subject. Image data (radiation dose) in each direction is collected, and image reconstruction processing is performed to obtain a SPECT image. As shown in FIG. 1 and FIG. 2, the top plate 5 of the bed 4 is located at a position corresponding to the imaging region (for example, the heart) of the subject 6 supported on the top plate 5 from the side surface of the top plate 5 to the center. A notch 7 corresponding to the size of the region to be imaged is formed.

Next, the operation of the cutout portion 7 will be described with reference to FIG. In the case of collecting data by the 180-degree collection method, the detector 1 is located at the backside position of the subject 6 shown by the solid line from the position shown by the one-dot chain line above the subject 6 in the figure, that is, the position below the top plate. Rotate 180 degrees counterclockwise until. At this time, even if the detector 1 is rotated to a position where the top plate 5 is interposed between the subject 6 and the detector 1, the portion through which the subject 6 is seen from the detector 1 is notched. Since it is the part 7, the absorption or scattering of radiation on the top plate 5 does not occur at all, and raw data of the subject 6 can be obtained.

If the length L (see FIG. 2) of the cutout portion 7 is made larger than the width 1 (see FIG. 1) of the detector 1, the detector 1 can fit in the cutout portion 7, and The detector 1 can be brought close to the subject 6 at a position below the top plate. This is particularly advantageous when the detector 1 is rotated by an ellipse along the shape of the cross section of the subject 6.

As described above, in the above-described embodiment, the notch is provided only on one side of the top plate. However, in SPECT imaging or the like in which the 360-degree acquisition method (full scan) is performed, the notch is provided on both sides of the top plate. It is also possible to provide a section. It is also possible to prepare top plates with different sizes and shapes of cutouts and locations so that they can be attached to and detached from the bed body according to the imaging site.

[0013]

[Effect of the device]

 According to the ECT device of the present invention, the absorption and scattering of radiation by the top plate is eliminated, the contrast is improved, and the detector can be brought closer to the imaging site of the subject, thereby increasing the S / N ratio. The resolution is also increased, and the image quality of the SPECT image is significantly improved as a whole. In addition, it is economical because it is not necessary to form the top plate from a material that absorbs and scatters radiation, and an inexpensive general material can be selected in terms of strength and processing.

[Brief description of drawings]

FIG. 1 is a side view of an ECT apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view showing the configuration of the bed shown in FIG.

FIG. 3 is a III-III view of FIG. 1 for explaining the operation.

[Explanation of symbols]

1 ... Detector 2 ... Stand 3 ... Cart 4
… Bed 5… Top plate 6… Subject 7… Notch

Claims (1)

[Scope of utility model registration request] 1. A bed provided with a top plate for supporting a subject,
An ECT apparatus comprising at least one scintillation camera detector and a stand for holding the detector and rotating the detector about an axis parallel to the longitudinal axis of the top plate, comprising: An ECT device characterized in that a cutout portion is provided on a side portion.