NUCLEAR MEDICAL APPARATUS

Abstract

A nuclear medical apparatus for obtaining a distribution of a radioisotope in a subject by administering to a subject a radioactive medicine labeled with a radioisotope, detecting gamma rays given off from the radioisotope in a gamma-ray detecting section and counting the detected gamma rays in a count section. A correcting section is provided to correct for a count taken at the count section, by use of collection efficiency data determined according to the gamma-ray detecting section and an energy the gamma rays possesses.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.

FIG. 1 is a diagram showing the main arrangement of a nuclear medical apparatus according to a first embodiment of the invention;

FIG. 2 is a figure showing an example of a collection efficiency table;

FIG. 3 is a figure showing a way of thinking taking account of energy-dependent collection efficiency;

FIG. 4 is a figure showing an example of an image displayed on a display;

FIG. 5 is a figure for explaining the scattering-ray correction under a TEW scheme;

FIG. 6 is a flowchart showing a manner of preparing a collection efficiency table;

FIG. 7 is a diagram showing the main arrangement of a nuclear medical apparatus according to a second embodiment of the invention;

FIG. 8 is a flowchart for explaining the operation of the nuclear medical apparatus according to the second embodiment of the invention;

FIG. 9 is a figure for explaining a collection-window setting technique in the case a plurality of radioisotopes are administered;

FIGS. 10A, 10B and 10C are figures explaining an example of an image generated by the image generating section in the second embodiment;

FIG. 11 is a flowchart for explaining the operation of the nuclear medical apparatus according to a modification to the second embodiment; and

FIG. 12 is a figure showing an example of a combined image generated by the image generating section in the modification to the second embodiment.

Claims

1. A nuclear medical apparatus for obtaining a distribution of a radioisotope in a subject by administering to a subject a radioactive medicine labeled with a radioisotope, detecting gamma rays given off from the radioisotope in a gamma-ray detecting section and counting the detected gamma rays in a count section, the apparatus characterized by: having a correcting section that corrects for a count taken at the count section, by use of collection efficiency data determined according to the gamma-ray detecting section and an energy the gamma rays possesses.

2. A nuclear medical apparatus comprising: a gamma-ray detecting section that detects gamma rays given off from a radioisotope contained in a radioactive medicine administered to a subject and determining an incident site of the gamma rays and an energy the gamma rays possesses;a gamma-ray collecting section that gathers the gamma rays, in a case gamma rays detected at the gamma-ray detecting section have an energy fallen within a predetermined collection window;an output section that outputs a value commensurate with a collection efficiency of the gamma rays determined according to a type of the gamma-ray detecting section and an energy the gamma rays possesses;a gamma-ray count section that determines a count value of the gamma rays entered the gamma-ray detecting section depending upon the value commensurate with a collection efficiency outputted from the output section, in a case gamma rays are gathered in the gamma-ray collecting section; anda display section that displays an image based on the determined count value of gamma rays.

3. A nuclear medical apparatus according to claim 2, wherein the output section is to output a reciprocal to the collection efficiency as a value commensurate with the collection efficiency, the gamma-ray count section adding the reciprocal to the collection efficiency each time gamma rays are gathered by the gamma-ray collecting section, thereby determining a count value of gamma rays.

4. A nuclear medical apparatus according to claim 2, wherein the gamma-ray detecting section includes a collimator that regulates an incident angle of gamma rays of from the radioisotope, the gamma-ray detecting section being in a type including at least a type of the collimator.

5. A nuclear medical apparatus according to claim 2, wherein the gamma-ray collecting section includes a first window circuit that gathers gamma rays, in a case gamma rays detected at the gamma-ray detecting section has an energy fallen within a first collection window,a second window circuit that gathers gamma rays, in a case gamma rays detected at the gamma-ray detecting section has an energy fallen within a second collection window adjacent to and on a lower energy side than the first collection window, anda third window circuit that gathers gamma rays, in a case gamma rays detected at the gamma-ray detecting section has an energy fallen within a third collection window adjacent to and on a higher energy side of the first collection window,the gamma-ray count section determining count values of the gamma rays respectively gathered in the first, second and third window circuits, separately and on an incident-site basis,wherein included is a scatter correcting section that makes a scattering ray correction depending upon the separately determined count values of gamma rays prior to displaying an image on the display section.

6. A nuclear medical apparatus comprising: a gamma-ray detecting section that detects gamma rays given off from radioisotopes different in energy peak and respectively contained in a plurality of radioactive medicines administered to a subject, and determines an incident site of the gamma rays and an energy the gamma rays possesses;a gamma-ray collecting section that gathers the detected gamma rays on each of the radioisotopes; anda display section that displays an image on each of the radioisotopes gathered.

7. A nuclear medical apparatus according to claim 6, further comprising an output section that outputs a value commensurate with a collection efficiency of gamma rays determined by the gamma-ray detecting section according to a type of the gamma-ray detecting section and an energy the gamma rays possesses, anda gamma-ray count section that determines a count value of gamma rays entered the gamma-ray detecting section on each of the incident sites and of the radioisotopes depending upon the value commensurate with a collection efficiency outputted from the output section, in a case gamma rays are gathered in the gamma-ray collecting section,the display section displaying the image depending upon the count value of gamma rays on each of the radioisotopes counted.

8. A nuclear medical apparatus according to claim 6, wherein the display section is to display a plurality of images separately and on a radioisotope-by-radioisotope basis.

9. A nuclear medical apparatus according to claim 8, wherein the display section is to display, together with the image, at least any of a name of the radioactive medicine administered to the subject and a name of a protein to image by utilization of the radioactive medicine.

10. A nuclear medical apparatus according to claim 6, wherein the display section is to display the image with colors on a radioisotope-by-radioisotope basis.

11. A nuclear medical apparatus according to claim 7 wherein the display section is to output a reciprocal to the collection efficiency as a value commensurate with the collection efficiency, the gamma-ray count section adding a reciprocal to the collection efficiency each time gamma rays are gathered by the gamma-ray collecting section, thereby determining a count value of gamma rays.