JPH0374347B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to radioisotopes (hereinafter abbreviated as "R・I") that collect at specific sites when administered to the human body.
The present invention relates to a scintillation camera for diagnosing the function of a specific region by expressing the distribution status of the scintillation as an image, and particularly relates to a scintillation camera that improves the efficiency of scintillation detection.

[Technical background of the invention and its problems]

A scintillator that detects scintillation caused by R/I radiation administered to a subject, displays the scintillation position on the detector surface in an X-Y coordinate system, and diagnoses the diseased area using the integrated image. Diagnosis using a camera has been conventionally performed.

By the way, in the scintillation camera, the setting of a so-called region of interest, which represents only a specific part on the monitor, is performed by inhibiting the position signal electrically or by software using a data processing device. Ta.

For example, when the target region shown by 2 in FIG. 1 (for example, a specific region of a subject) is captured by the detector surface 1 of a scintillation camera, the accumulated image
As shown in FIG. 2, a background region 4 other than the target region 2 is included, and the region of interest is set as shown at 5.

However, according to the conventional method, since the region of interest is set after also electrically processing the background region, the counting rate of the region of interest decreases accordingly.

[Object of the Invention] The present invention has been made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a scintillation camera that improves the efficiency of scintillation detection and allows easy setting of a region of interest.

[Summary of the invention]

The outline of the present invention for achieving the above object includes a scintillator capable of converting radiation generated from a radioisotope administered to a subject into scintillation light, and a light guide laminated on the scintillator to convert the scintillation light into scintillation light. a photomultiplier tube that generates photoelectrons corresponding to the photoelectrons and multiplies the photoelectrons; a position signal conversion means that converts an output signal of the photomultiplier tube into a position signal; and an output signal of the position signal conversion means. A scintillation camera comprising: a display means for displaying an image based on the scintillation camera; and a region of interest setting means for setting a region of interest in the image displayed by the display means; and a light shielding means capable of changing color so that scintillation light cannot pass through in an appropriate shape, and a color change that specifies a discoloration area of the light shielding means based on the region of interest set by the region of interest setting means. area specifying means;
The apparatus is characterized by comprising a light shielding control means for discoloring a specific region of the light shielding means so that scintillation light cannot pass therethrough, depending on the output data of the discoloration region specifying means.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 is a schematic block diagram showing the configuration of a scintillation camera according to the present invention. Means (hereinafter also referred to as "ROI setting means") 1
5, discoloration area designation means 17 and liquid crystal control means 1
It consists of 6.

The detection means 6 detects R.I. administered to the subject.
The radiation generated by the scintillation light (hereinafter referred to as
scintillator 7 that converts into light (also simply called "light")
a light guide 11 stacked on the scintillator 7; a liquid crystal film 8 interposed between the light guide and the scintillator and capable of changing color so as not to transmit scintillation light; and a plurality of liquid crystal films arranged on the light guide 11. The output of the photomultiplier tubes 12a to 12n, that is, the output of the detection means 6, is input to the position signal conversion means 13 disposed at a subsequent stage. Ru.

The position signal detection means converts the output signal of the detection means 6 into a position signal, and the output signal is provided for image display on the display means 14 disposed at a subsequent stage.

Further, the ROI setting means 15 is constituted by, for example, a joy stick, a track ball, a light pen, etc.
A region of interest (hereinafter also referred to as "ROI") is set in the image displayed by 4, and the output thereof is sent to the display means 14 and discoloration region specifying means 17 disposed at a subsequent stage via the display means 14. is input.

The discoloration area specifying means 17 is constituted by, for example, a central processing unit (CPU), and based on the region of interest set by the ROI setting means 15, information (data) for setting a discoloration area of the liquid crystal film 8 in the detection means 6 is provided. ), and this information is
It is transferred to the liquid crystal control means 16 arranged at a subsequent stage.

The liquid crystal control means 16 controls the discoloration area specifying means 1.
Based on the information transferred from the liquid crystal film 7, a specific area of the liquid crystal film 8 is changed in color, and its output is applied to a transparent electrode (not shown) of the liquid crystal film 8.

Next, the operation of the scintillation camera configured as described above will be explained.

The scintillator 7 generates scintillation light by radiation generated from the R/I projected onto the subject. The scintillation light is transmitted through the liquid crystal film 8.
(At this time, the liquid crystal film 8 has not changed color and is therefore transparent) and enters the photomultiplier tubes 12a to 12n via the light guide 11. The photomultiplier tubes 12a to 12n generate photoelectrons corresponding to the scintillation light (photoelectric effect) on their photocathode surfaces, multiply the photoelectrons, and output them to the position signal conversion means 13. After the photoelectrons are converted into a position signal by the position signal conversion means 13, the photoelectrons are displayed as an image on the display means 14.

The operator uses the ROI setting means 15 to set a target region, that is, a region of interest, in the display image of the display means 14 . The set region of interest is displayed on the discoloration region specifying means 1 via the display means 14.
7 and used to generate information for setting the discoloration area of the liquid crystal film 8. Based on the information generated by the discoloration area specifying means 17, the liquid crystal control means 16 discolors a specific area of the liquid crystal film 8, making it impossible for scintillation light to pass through the specific area.

Here, the specific area of the liquid crystal film 8 refers to the specific area of the liquid crystal film 8.
This region is outside the region of interest set by the ROI setting means 15 and is an unnecessary background part. Therefore, only the region (portion) of the liquid crystal film 8 corresponding to the region of interest is transparent and allows scintillation light to pass therethrough.

In this way, by changing the color of the liquid crystal film 8 interposed between the light guide 11 of the detection means 6 and the scintillator 7 according to the region of interest, it is possible to detect areas (organs) other than the region of interest set. Since the scintillation light is blocked, the display means 14 shows
Only the image of the target area with the region of interest set is displayed without distortion, and the counting rate is significantly improved, especially when there are many background areas compared to the target area. It turns out.

Furthermore, as described above, the photomultiplier tubes 12a to
The light guide 11 between the light guide 12n and the liquid crystal film 8 becomes a space for light, and the light also enters the photomultiplier tubes 12a to 12n that are blocked by the liquid crystal, thereby reducing distortion during position calculation.

It goes without saying that the present invention is not limited to the embodiments described above, and that modifications can be made as appropriate within the scope of the gist of the present invention.

For example, in the embodiment, the discoloration area specifying means 1
Although 7 is configured with a CPU, the present invention is not limited to this, and even if it is configured with hardware or firmware based on microprogramming, the same effects as in the above embodiment can be achieved. Furthermore, although the liquid crystal film was used as the light shielding means in the above embodiments, other members having the same function may be used instead.

〔Effect of the invention〕

According to the present invention described above, since the display of the region of interest is performed by shielding the scintillation light itself, the scintillation detection efficiency of the target region (region of interest) is improved, and the region of interest of an arbitrary shape is set. A scintillation camera can be provided where this can be easily performed.

[Brief explanation of drawings]

1 and 2 are explanatory diagrams for explaining the setting of a region of interest in a conventional device, and FIG. 3 is an explanatory diagram showing the configuration of a scintillation camera according to the present invention. 6...Detection means, 7...Scintillator, 8...
Liquid crystal film, light shielding means, 11...Light guide, 1
2a to 12n...Photomultiplier tube, 13...Position signal conversion means, 14...Display means, 15...ROI setting means (region of interest setting means), 17...Liquid crystal control means (light shielding control means) .

Claims (1)

[Claims] 1 A scintillator capable of converting radiation generated from a radioisotope administered to a subject into scintillation light, and a light guide laminated to the scintillator to generate photoelectrons corresponding to the scintillation light, and to generate photoelectrons according to the scintillation light. a photomultiplier tube that multiplies the output signal of the photomultiplier tube, a position signal conversion means that converts the output signal of the photomultiplier tube into a position signal, a display means that displays an image based on the output signal of the position signal conversion means, and the display. and a region of interest setting means for setting a region of interest in an image displayed by the scintillation camera, the scintillation camera is interposed between the scintillator and the light guide and transmits scintillation light in an appropriate shape. a light shielding means capable of irreversibly changing color; a discoloration region specifying means for specifying a discoloration region of the light shielding means based on the region of interest set by the region of interest setting means; and an output of the discoloration region specifying means. A scintillation camera characterized by comprising: a light shielding control means that changes color of a specific area of the light shielding means so that scintillation light cannot pass therethrough according to data.