Configurable multiple detector nuclear medicine gantry

• US 5,929,446 A
• Filed: 05/07/1998
• Issued: 07/27/1999
• Est. Priority Date: 11/27/1996
• Status: Expired due to Term

• Current Assignee: Picker International, Inc. (Marconi Holdings Company Limited)
• Original Assignee: Picker International, Inc. (Marconi Holdings Company Limited)
• Inventors: Plummer, Steven J., Barnes, Jacin C.
• Primary Examiner(s): Hannaher, Constantine
• Application Number:
  US09/074,236
• Time in Patent Office: 446 Days
• Field of Search: 250/363.05, 250/363.04
• US Class Current: 250/363.05
• CPC Class Codes: A61B 6/037 Emission tomography
• CPC Class Codes: A61B 6/4258 for detecting non x-ray radiation, e.g. gamma radiation A61B6/037 takes precedence
• CPC Class Codes: G01T 1/1642 using a scintillation crystal and position sensing photodetector arrays, e.g. ANGER cameras

Abstract

A transformable gamma camera includes detectors mounted for circumferential movement with respect to a rotating gantry. The rotating gantry includes radial bores at desired angular positions about the rotating gantry. The stationary gantry includes a docking station such as a bore. A coupling mechanism allows the detectors to be coupled to the bores in the rotating gantry or to the docking station. Each of the detectors is movable radially with respect to the rotating gantry'"'"'s axis of rotation and tangentially to the imaging region. The gamma camera is readily transformable between 120 degree, orthogonal, and opposed detector configurations; a plurality of aperture sizes can also be defined.

Claims

1. A gamma camera comprising:

a first radiation sensitive detector having a radiation sensitive face which faces an examination region, the first detector being movable in a direction oblique to its face;

a second radiation sensitive detector having a radiation sensitive face which faces the examination region, the second detector being movable in a direction oblique to its face;

a third radiation sensitive detector having a radiation sensitive face which faces the examination region, the third detector being movable in a direction oblique to its face, the detectors being positionable in at least first and second relative angular orientations about the examination region;

drive means for rotating the radiation sensitive detectors about the examination region.

2. The gamma camera of claim 1 further including a rotating gantry portion, wherein the angular position of the first and second detectors with respect to the rotating gantry portion is selectively adjustable and wherein the angular position of the third detector with respect to the rotating gantry portion is fixed.

3. The gamma camera of claim 2 wherein, at the first relative angular orientation, the detectors are disposed at equal angular intervals about the examination region so as to define an aperture, each of the detectors being movable in a direction oblique to its face so as to define at least first and second aperture sizes.

4. The gamma camera of claim 3 wherein the first aperture size is adapted for imaging the human head and the second aperture size is adapted for imaging the human body.

5. The gamma camera of claim 3 wherein, at the second relative angular orientation, the first and second detectors are disposed in an opposed configuration.

6. The gamma camera of claim 3 wherein, at the second relative angular orientation, the first and second detectors are disposed in an orthogonal configuration.

7. The gamma camera of claim 2 wherein the first radiation sensitive detector comprises an array of photomultiplier tubes and a scintillator disposed between the photomultiplier tubes and the examination region.

8. The gamma camera of claim 1 including a drive mechanism adapted to move the first detector in a direction perpendicular to its face and a drive mechanism adapted to move the first detector in a direction parallel to its face.

9. A gamma camera comprising:

a first radiation sensitive detector having a radiation sensitive face which faces an examination region adapted to accept the anatomy of a patient;

a second radiation sensitive detector having a radiation sensitive face which faces the examination region;

a third radiation sensitive detector having a radiation sensitive face which faces the examination region, the first, second, and third detectors being positionable in a first relative angular orientation wherein the detectors are disposed at equal angular intervals about the examination region so as to define an aperture and in a second relative angular orientation;

wherein, at the first relative angular orientation, the detectors are positionable so as to define two or more aperture sizes.

10. The gamma camera of claim 9 comprising means for moving each of the first, second, and third detectors in a direction which has a component tangential to the examination region and a component radial with respect to the examination region.

11. The gamma camera of claim 9 wherein, at the second relative angular orientation, the first and second detectors are disposed in an orthogonal configuration.

12. The gamma camera of claim 9 further including means for moving the first and second detectors in a direction oblique to their respective faces.

13. The gamma camera of claim 9 including a drive for moving each of the first and second detectors in a direction tangential to the imaging region and a drive for moving each of the first and second detectors radially with respect to the examination region.

14. The gamma camera of claim 9 wherein the gamma camera includes a stationary frame, a rotating gantry, and means for selectively coupling the first and second detectors to the rotating gantry and the stationary frame to vary the relative angular position of the detectors about the rotating gantry.

15. A method of transforming the configuration of a gamma camera having first, second, and third radiation sensitive detectors disposed about an examination region, the method comprising the steps of:

disposing the detectors in a first relative angular orientation with respect to the examination region;

disposing the detectors in a second relative angular orientation with respect to the examination region so as to define an aperture adapted for imaging the anatomy of a human patient;

moving the each of the first, second, and third detectors in a direction oblique to its respective face so as to adjust the size of the aperture.

16. The method of claim 15 wherein the first relative angular orientation is one of an orthogonal and an opposed configuration.

17. The method of claim 15 wherein the step of moving includes

moving the first detector in a direction perpendicular to its face and in a direction parallel to its face;

moving the second detector in a direction perpendicular to its face and in a direction parallel to its face.

18. The method of claim 15 wherein the second angular orientation is one in which the detectors are disposed at equal angular intervals about the examination region.

19. The method of claim 18 wherein the aperture size is one of a first aperture size adapted for imaging the human head and a second relatively larger aperture size adapted for imaging the human body.

20. The method of claim 15 further including rotating the detectors about the examination region.

21. A method of transforming the configuration of a gamma camera having first, second, and third radiation sensitive detectors, each detector having radiation sensitive face which faces an examination region adapted to accept a portion of the human anatomy, the method including the steps of:

disposing the detectors in a first relative angular orientation about the examination region;

disposing the detectors in a second relative angular orientation wherein the detectors are disposed at equal angular intervals with respect to the examination region so as to define an aperture adapted to accept a portion of the anatomy;

adjusting the size of the aperture.

22. The method of claim 21 wherein each detector has a width and defines a side of a polygonal aperture, each side of the aperture having a dimension less than the width of the corresponding detector.

23. The method of claim 22 wherein, at the first relative angular orientation, the detectors are disposed in an orthogonal configuration.

24. The method of claim 21 including moving the first and second detectors in a direction oblique to their respective faces while the detectors are disposed in the first relative angular orientation.