Localization of a radioactive source

• US 8,198,600 B2
• Filed: 04/21/2011
• Issued: 06/12/2012
• Est. Priority Date: 08/12/2004
• Status: Expired due to Fees

• Current Assignee: Navotek Medical Ltd.
• Original Assignee: Navotek Medical Ltd.
• Inventors: Neustadter, David Maier, Kornblau, Giora
• Primary Examiner(s): Vanore, David A
• Application Number:
  US13/091,775
• Publication Number:
  US 20110198510A1
• Time in Patent Office: 418 Days
• Field of Search: 250/393, 250/394, 250/395, 250/493.1, 600/3, 600/424, 600/425
• US Class Current: 250/393
• CPC Class Codes: A61B 2034/105 Modelling of the patient, e.g. for ligaments or bones
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2034/2068 using pointers, e.g. pointers having reference marks for determining coordinates of body points
• CPC Class Codes: A61B 2090/101 for stereotaxic radiosurgery
• CPC Class Codes: A61B 2090/392 Radioactive markers
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 5/1127 using markers
• CPC Class Codes: A61B 6/4258 for detecting non x-ray radiation, e.g. gamma radiation A61B6/037 takes precedence
• CPC Class Codes: A61B 90/36 Image-producing devices or illumination devices not otherwise provided for
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: G01T 1/2907 Angle determination; Directional detectors; Telescopes prospecting by the use of nuclear radiation, e.g. of natural or induced radioactivity G01V5/00

Abstract

An angle-responsive sensor, comprising: a radiation detector adapted to detect ionizing radiation; at least one collimator arranged to block radiation from reaching the detector in a manner dependent on a relative orientation of a radiation source, the detector and the collimator, the detector and the collimator defining an aim for the sensor; and circuitry coupled to the detector and which generates an output signal which varies as a function of the relative orientation, wherein the detector and the collimator are arranged to have a working volume of at least 10 cm in depth and having an angular width, such that the slope of the signal as a function of angle varies by less than a factor of 2 over the working volume.

Claims

1. An angle-responsive sensor, comprising:

a radiation detector adapted to detect ionizing radiation;

at least one collimator arranged to block radiation from reaching the detector in a manner dependent on a relative orientation of a radiation source, the detector and the collimator, the detector and the collimator defining an aim for the sensor; and

circuitry coupled to the detector and which generates an output signal which varies as a function of the relative orientation,

wherein the detector and the collimator are arranged to have a working volume of at least 10 cm in depth and having an angular width, such that the slope of the signal as a function of angle varies by less than a factor of 2 over the working volume.

2. The angle-responsive sensor of claim 1, wherein said signal is near linear over said working volume.

3. The angle-responsive sensor of claim 1, wherein said working volume has an angular range of at least 10 milliradians.

4. The angle-responsive sensor of claim 1, wherein said working volume has an angular range of at least 20 milliradians.

5. The angle-responsive sensor of claim 1, wherein said detector comprises at least two separate sections.

6. The angle-responsive sensor of claim 5, wherein circuitry generates said signal based on a combining of contributions of at least two separate sections of said radiation detector.

7. The angle-responsive sensor of claim 6, wherein said two sections each have different angular direction of maximum detection.

8. The angle-responsive sensor of claim 1, wherein said circuitry generates said signal for a source distance of at least 10 cm.

9. The angle-responsive sensor of claim 1, wherein said circuitry generates said signal for a source distance of at least 20 cm.

10. The angle-responsive sensor of claim 1, wherein said working volume has a range of depths having a ratio of at least 1:

2.

11. The angle-responsive sensor of claim 5, wherein the detector comprises two sections, each one with a different focal area.

12. The angle-responsive sensor of claim 5, wherein said collimator provides multiple focal points for each of said sections.

13. The angle-responsive sensor of claim 5, wherein said collimator allows wide angle radiation at a spatial angle of at least 10 degrees for at least two sections.

14. The angle-responsive sensor of claim 5, wherein a focal point of a first section is distanced from a focal point of a second section in a direction parallel to said detector, a distance of at least 1 mm.

15. The angle-responsive sensor of claim 14, wherein the detector comprises additional sections with additional focal points distanced along said parallel direction.

16. The angle-responsive sensor of claim 14, wherein the sensor has a relatively linear angular response over an angle range of at least 10 milliradians.

17. The angle-responsive sensor of claim 14, wherein said sensor has a relatively linear angular response over a depth range of at least 10 cm.

18. The angle-responsive sensor of claim 5, comprising fewer than 50 separately read detector sections.

19. The angle-responsive sensor of claim 18, comprising fewer than 20 separately read detector sections.

20. The angle-responsive sensor of claim 19, comprising fewer than 10 separately read detector sections.