Hand held camera with tomographic capability

• US 20010056234A1
• Filed: 04/11/2001
• Published: 12/27/2001
• Est. Priority Date: 04/12/2000
• Status: Active Grant

• Current Assignee: Compania Mexicana de Radiologia CGR SA de CV
• Original Assignee: Naviscan Pet Systems Inc (Compania Mexicana de Radiologia CGR SA de CV)
• Inventors: Weinberg, Irving N.
• Granted Patent: US 6,628,984 B2
• Time in Patent Office: Days
• US Class Current: 600/436
• 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 1/2985 In depth localisation, e.g. using positron emitters; Tomographic imaging (longitudinal and transverse section imaging; apparatus for radiation diagnosis sequentially in different planes, steroscopic radiation diagnosis); using external radiation sources A61B6/02

Abstract

A tomographic imaging system includes a moveable detector or detectors capable of detecting gamma radiation; one or more position sensors for determining the position and angulation of the detector(s) in relation to a gamma ray emitting source; and a computational device for integrating the position and angulation of the detector(s) with information as to the energy and distribution of gamma rays detected by the detector and deriving a three dimensional representation of the source based on the integration. A method of imaging a radiation emitting lesion located in a volume of interest also is disclosed.

Claims

1. A tomographic imaging system comprising:

a moveable detector that is capable of detecting gamma radiation;

a first position sensor for determining the position and angulation of the detector in relation to a gamma ray emitting source; and

a computational device for integrating the position and angulation of the detector with information as to the energy and distribution of gamma rays detected by the detector and deriving a three dimensional representation of the source based on the integration.

2. The system of

claim 1

further comprising a graphical user interface for displaying the three dimensional representation.

3. The system of

claim 1

, wherein the detector is a gamma camera.

4. The system of

claim 1

, wherein the detector includes shielding material.

5. The system of

claim 4

, wherein the shielding material is interrupted by a pinhole, to form a pinhole collimator.

6. The system of

claim 4

, wherein the shielding material is interrupted by a set of pinholes, to form a coded-aperture collimator.

7. The system of

claim 4

, wherein the shielding material is interrupted by a set of pinholes configured to form a parallel hole collimator.

8. The system of

claim 4

, wherein the shielding material is interrupted by a set of pinholes configured to form a converging hole collimator.

9. The system of

claim 4

, wherein the shielding material is interrupted by a set of pinholes configured to form a diverging hole collimator.

10. The system of

claim 4

, wherein the shielding material is interrupted by a set of pinholes configured to form a slant hole collimator.

11. The system of

claim 1

, further comprising a second detector that is capable of detecting gamma radiation.

12. The system of

claim 11

, wherein the computational device integrates information as to the energy and distribution of gamma rays detected by each detector with the position and angulation of each detector.

13. The system of

claim 11

, further comprising a data acquisition apparatus for determining whether the detectors are struck by the gamma rays coincidently.

14. The system of

claim 11

, wherein one or more of the detectors is disposed in a body cavity.

15. The system of

claim 11

further comprising a needle inserted through an aperture in one of the detectors, the needle providing a virtual needle tip that can be displayed on a graphic user interface.

16. The system of

claim 2

further comprising a needle with a second position sensor affixed thereto, the second position sensor capable of generating a virtual needle tip that can be displayed on the graphic user interface.

17. The system of

claim 1

, wherein the detector is a Compton camera.

18. A tomographic imaging system comprising:

a moveable detector that is capable of detecting radiation;

a position sensor for determining the position and angulation of the detector in relation to a radiation emitting source; and

a computational device for integrating the position and angulation of the detector with information as to the energy and distribution of radiation detected by the detector and deriving a three dimensional representation of the source based on the integration.

19. The system of

claim 18

further comprising a graphical user interface for displaying the three dimensional representation.

20. The system of

claim 18

further comprising multiple radiation detectors.

21. The system of

claim 20

, wherein the position sensor records the position and angulation of one or more of the detectors in relation to the source.

22. The system of

claim 20

, wherein the computational device integrates the position and angulation of one or more of the detectors with information as to the source and distribution of radiation detected by one or more of the detectors and derives a three dimensional representation of the source based on the integration.

23. The system of

claim 18

, wherein the detector is sensitive to gamma radiation.

24. The system of

claim 18

, wherein the detector is sensitive to electromagnetic radiation.

25. The system of

claim 18

, wherein the detector is sensitive to particulate radiation.

26. The system of

claim 18

, wherein the detector is a handheld gamma camera

27. The system of

claim 18

, wherein the detector is a Compton camera.

28. A tomographic imaging system comprising:

a moveable means for detecting radiation;

a means for determining the position and angulation of the detector means in relation to a radiation emitting source; and

a means for integrating the position and angulation of the detector means with information as to the energy and distribution of radiation detected by the detector means and deriving a three dimensional representation of the source based on the integration.

29. The system of

claim 28

further comprising a means for displaying the three dimensional representation as an image or set of images.

30. The system of

claim 28

wherein the detector means is sensitive to gamma radiation.

31. The system of

claim 28

wherein the detector means is sensitive to electromagnetic radiation.

32. The system of

claim 28

wherein the detector means is sensitive to particulate radiation.

33. A method of imaging a radiation emitting lesion located in a volume of interest comprising the steps of:

positioning a detector that is sensitive to radiation at multiple locations in relation to the lesion to obtain information as to the energy and distribution of the radiation detected by the detector;

recording the positions and angulations of the detector in relation to the lesion;

integrating the positions and angulations of the detector with the energy and distribution information; and

deriving a three dimensional representation of the lesion based on the integration.

34. The method of

claim 33

, wherein the representation of the lesion is derived using backprojection.

35. The method of

claim 33

, wherein the representation of the lesion is derived using reconstruction.

36. The method of

claim 35

, wherein the reconstruction is performed using an iterative method.

37. The method of

claim 36

wherein the iterative method includes performing a Monte Carlo simulation.

38. The method of

claim 33

, wherein a virtual ray within a volume of interest is defined by two points upon the boundary of the volume of interest traversed by a backprojected ray, and where the virtual ray can be reconstructed or backprojected.

39. The method of

claim 33

wherein the detector is sensitive to gamma radiation and the lesion emits gamma radiation.

40. The system of

claim 33

wherein the detector is sensitive to electromagnetic radiation and the lesion emits electromagnetic radiation.

41. The system of

claim 33

wherein the detector is sensitive to particulate radiation and the lesion emits particulate radiation.

42. The method of

claim 39

wherein the detector comprises first and second detector components.

43. The method of

claim 42

including the step of generating a set of virtual gamma rays using an event location on the first detector component as one point along the ray, and an event location on the second detector component as a second point along the ray.

44. The method of

claim 42

, further comprising the step of determining the amount of energy deposited in each of the detector components when energy from a gamma ray is deposited in both the detection components.

45. The method of

claim 42

further comprising the step of using the difference in energy deposited in each detection component to determine a possible angular deviation direction for the gamma ray.

46. The method of

claim 33

, further comprising the step of inserting the detector into a body cavity.

47. The method of

claim 33

, wherein a virtual ray within a volume of interest is defined by two points upon a boundary of the volume of interest traversed by a backprojected ray.

48. The method of

claim 47

where the virtual ray can be reconstructed or backprojected.

49. A method of imaging a gamma ray emitting lesion in a patient comprising the steps of:

positioning a gamma camera that is sensitive to gamma radiation at multiple locations in relation to the lesion to obtain information as to the energy and distribution of gamma rays detected by the detector;

recording the positions and angulations of the camera in relation to the lesion;

integrating the positions and angulations of the camera with the energy and distribution information; and

deriving a three dimensional representation of the lesion based on the integration.

50. The method of

claim 49

wherein the representation of the lesion is derived using backprojection.

51. The method of

claim 49

wherein the representation of the lesion is derived using reconstruction.

52. A method of radioactive waste surveillance comprising the steps of:

positioning a detector at multiple locations in relation to the waste, the detector being sensitive to radiation emitted by the waste and providing information as to the energy and distribution of the radiation detected by the detector;

recording the positions and angulations of the detector in relation to the waste;

integrating the positions and angulations of the detector with the source and distribution information; and

deriving a three dimensional representation of the waste based on the integration.