Data processing for real-time tracking of a target in radiation therapy

• US 20060100509A1
• Filed: 07/25/2005
• Published: 05/11/2006
• Est. Priority Date: 07/23/2004
• Status: Active Grant

• Current Assignee: Varian Medical Systems Incorporated (Siemens AG)
• Original Assignee: Varian Medical Systems Incorporated (Siemens AG)
• Inventors: Wright, J. Nelson, Dimmer, Steven C., Phillips, Stephen C., Seghers, Ryan K.
• Granted Patent: US 8,095,203 B2
• Time in Patent Office: Days
• US Class Current: 600/426
• CPC Class Codes: A61B 2090/3958 emitting a signal
• CPC Class Codes: A61N 2005/1051 using an active marker markers in general A61B90/39
• CPC Class Codes: A61N 5/1049 for verifying the position of the patient with respect to the radiation beam
• CPC Class Codes: A61N 5/107 in real time, i.e. during treatment

Abstract

A facility for processing data is described. The facility receives a stream of digital location indications, each location indication identifying a location of a patient while undergoing radiation therapy. In response to each location indication of the string, in substantially real-time relative to the receipt of the position indication, the facility performs an action responsive to the location indication.

Claims

1. A method in a computing system for processing data, comprising:

receiving a stream of digital location indications, each location indication identifying a location of a target in a human patient using a marker secured in the patient such that the marker is substantially fixed relative to the target; and

in response to each location indication of the stream, in substantially real-time relative to the receipt of the position indication, performing an action responsive to the location indication.

2. The method of claim 1 wherein each received location indication indicates a location occupied by the target substantially immediately before the location indication is received.

3. The method of claim 1 wherein each location indication indicates a location of the target in three dimensions.

4. The method of claim 1 each location indication represents a vector from a machine isocenter point.

5. The method of claim 1 wherein each location indication is based upon interrogation of a plurality of passive magnetic markers attached to the target.

6. The method of claim 1 wherein each location indication indicates a relative location that is relative to a target location located with respect to a plurality of target-attached markers.

7. The method of claim 1 wherein each location indication indicates the position of a predetermined radiation treatment site of the target.

8. The method of claim 1 wherein each location indication indicates the location of the target relative to a location within one or more paths established for the propagation of radiation energy.

9. The method of claim 1 wherein the performed action comprises augmenting a displayed graph of locations to include the location indicated by the location indication.

10. The method of claim 9 wherein radiation therapy is performed in a radiation therapy enclosure, and wherein the augmented graph is displayed on a device outside the radiation therapy enclosure.

11. The method of claim 1 wherein the performed action comprises persistently storing information reflecting the location indicated by the location indication.

12. The method of claim 1 and wherein each location indication of the received stream of digital location indications identifies the location of the target while the target is undergoing radiation therapy, and wherein the performed action comprises:

determining whether the location indicated by the location indication merits modifying a parameter of the radiation treatment; and

where the location indicated by the location indication merits modifying a parameter of the radiation treatment, performing a mid-treatment modification to a parameter of the radiation treatment in accordance with the location indicated by location indication.

13. The method of claim 12 wherein the radiation treatment has at least one beam shape parameter specifying a cross-sectional shape of a radiation beam to be projected toward the target, and wherein the performed modification is to the beam shape parameter.

14. The method of claim 12 wherein the radiation treatment has a beam direction parameter specifying a direction in which a radiation beam is projected toward the target, and wherein the performed modification is to the beam direction parameter.

15. The method of claim 12 wherein the radiation treatment has an intensity parameter specifying a radiation intensity with which the target is to be treated, and wherein the performed modification is to the intensity parameter.

16. The method of claim 12 wherein the radiation treatment has at least one couch location parameter specifying a location of the couch bearing the target relative to the radiation treatment, and wherein the performed modification is to the couch location parameter.

17. The method of claim 12 wherein the radiation treatment has at least one couch orientation parameter specifying a orientation of the couch bearing the target relative to the radiation treatment, and wherein the performed modification is to the couch orientation parameter.

18. The method of claim 1 wherein the performed action comprises:

comparing the location indicated by the location indication with a predefined volume; and

where the location indicated by the location indication falls outside the predefined volume, presenting a warning.

19. The method of claim 18 wherein the warning is an audible warning.

20. The method of claim 18 wherein the warning is a visual warning.

21. The method of claim 18 wherein the warning is a redundant visual warning.

22. The method of claim 20 wherein the warning is displayed in a manner designed to warn a technician.

23. The method of claim 20 wherein the warning is displayed in a manner designed to warn the target.

24. The method of claim 1 wherein the performed action comprises:

comparing the location indicated by the location indication with a predefined volume; and

where the location indicated by the location indication falls outside the predefined volume, suspending radiation treatment in process during the receipt of the stream.

25. The method of claim 1 wherein the received stream of digital location indications is obtained using one or more markers attached to the target.

26. The method of claim 1 wherein the received stream of digital location indications is obtained using one or more markers implanted subcutaneously in the target.

27. The method of claim 1 wherein the received stream of digital location indications has a frequency of at least 20 hertz.

28. The method of claim 1 wherein the received stream of digital location indications has a latency of no more than 50 milliseconds.

29. The method of claim 1 wherein the received stream of digital location indications has a latency of no more than 200 milliseconds.

30. The method of claim 1 wherein the stream of digital location indications is received at a rate that permits the location of the marker to be tracked with an area that does not exceed a threshold of five millimeters.

31. The method of claim 1 wherein the action responsive to each location indication of the stream is performed in substantially real-time relative to a measurement time associated with performing measurements upon which the position indication is based.

32. A computing system for processing data, comprising:

a data receiver subsystem that receives a stream of digital location indications, each location indication identifying a location of a target in a human patient using a marker secured in the patient such that the marker is substantially fixed relative to the target, the digital location indications being based upon locating the marker using non-ionizing radiation; and

a data processing subsystem that, in response to each location indication of the stream, in substantially real-time relative to the receipt of the position indication by the data receiver subsystem, performs an action responsive to the location indication.

34. The computer-readable medium of claim 32 wherein the action is performed in substantially real-time relative to a measurement time associated with a measurement upon which the position indication is based.

33. A computer-readable medium whose contents cause a computing system to perform a method for processing data, comprising:

receiving a digital location indication target in a human patient using a marker secured in the patient such that the marker is substantially fixed relative to the target, the digital location indications being based upon locating the marker using non-ionizing radiation; and

in response to receiving the location indication, in substantially real-time relative to the receipt of the position indication, performing an action responsive to the location indication.

35. One or more computer memories collectively containing a target tracking data structure, comprising:

a plurality of digital location indications, each location indication identifying a location of a target while undergoing radiation therapy, the location indications having been received in a stream substantially in real-time relative to their measurement.

36. One or more generated data signals collectively conveying a target tracking data structure, comprising:

a plurality of digital location indications, each location indication identifying a location of a target in a human patient using a marker secured in the patient such that the marker is substantially fixed relative to the target, the location indications having been received in a stream substantially in real-time relative to their measurement.

37. A method in a computing system for verifying a radiation therapy session, comprising:

reading a stored set of digital location indications each identifying a location of a target while undergoing radiation therapy during a distinguished therapy session; and

using the read digital location indications to review the provision of radiation therapy during the distinguished therapy session.

38. The method of claim 37 wherein reviewing the provision of radiation therapy during the distinguished radiation therapy session comprises verifying the radiation therapy session was conducted in accordance with a distinguished radiation therapy plan.

39. The method of claim 37 wherein the verification involves:

correlating the location indications with time-indexed information about treatment parameters; and

using the correlated information to determine that the radiation therapy was conducted in accordance with a radiation therapy plan.

40. The method of claim 37 wherein reviewing the provision of radiation therapy during the distinguished therapy session comprises displaying an indication of the location of the target throughout the distinguished therapy session.

41. The method of claim 37 wherein reviewing the provision of radiation therapy during the distinguished therapy session comprises determining a portion of the distinguished therapy session during which the target location was outside a predefined volume.

42. The method of claim 37 wherein reviewing the provision of radiation therapy during the distinguished therapy session comprises identifying the smallest volume containing all of the target locations.

43. The method of claim 37, further comprising:

reading a set of digital location indications for one or more patient-implanted markers from which the digital locations each identifying a location of the target were derived; and

generating a revised set of digital location indications each identifying a location of the target based upon a relationship between the location of the target and the locations of the markers other than was used to generate the read set of digital location indications each identifying the location of the target.