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

• US 8,095,203 B2
• Filed: 07/25/2005
• Issued: 01/10/2012
• 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.
• Primary Examiner(s): Chen, Tse
• Assistant Examiner(s): Brutus, Joel F
• Application Number:
  US11/190,205
• Publication Number:
  US 20060100509A1
• Time in Patent Office: 2,360 Days
• Field of Search: 600/407, 600/409, 600/410, 600426-428, 600473-478
• 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 computing system for processing data while a target is undergoing radiation therapy, comprising:

a data receiver subsystem that is configured to cause a processor of the computing system to receive a stream of digital location indications while a patient is undergoing a continuous radiation treatment session in substantially real-time during administration of radiation treatment, each location indication identifying a location of a target in the 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;

a data processing subsystem that is configured to cause the processor of the computing system to determine whether the locations indicated by one or more location indications merits modifying a parameter of the continuous radiation treatment session, wherein the determination is in response to one or more location indications of the stream received during the continuous radiation treatment session, in substantially real-time relative to the receipt of the position indication by the data receiver subsystem;

a modification subsystem that is configured to cause the processor of the computing system to modify the parameter during the continuous radiation treatment session in substantially real-time during administration of radiation treatment, without interrupting the continuous radiation treatment session, in response to the data processing subsystem determining that the locations indicated by one or more location indications merits modifying the parameter; and

a data storage subsystem that is configured to cause the processor of the computing system to store the received stream of digital location indications in an electronic transcript, wherein the electronic transcript includes time-indexed information correlating the location indications received by the data receiver subsystem with treatment parameters of the continuous radiation treatment session, wherein the time-indexed information is provided as a plurality of records, and wherein each record includes;

a measurement time at which a location indication was received by the data receiver subsystem; and

information adequate to determine a displacement from the target to a reference point during the continuous radiation treatment session.

2. The computing system 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 computing system of claim 1 wherein each location indication indicates a location of the target in three dimensions.

4. The computing system of claim 1 wherein each location indication represents a vector from the machine isocenter point.

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

6. The computing system 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 computing system of claim 1 wherein each location indication indicates the position of a predetermined radiation treatment site of the target.

8. The computing system 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 computing system of claim 1 further comprising a display subsystem that is configured to cause the processor of the computing system to augment a displayed graph of locations to include the location indicated by the one or more location indications.

10. The computing system 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 computing system of claim 1 wherein the electronic transcript is persistently stored.

12. The computing system of claim 1 wherein, when the locations indicated by one or more location indications merits modifying a parameter of the continuous radiation treatment session, performing a mid-treatment modification to a parameter of the continuous radiation treatment session in accordance with the locations indicated by the one or more location indications.

13. The computing system of claim 12 wherein the continuous radiation treatment session 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 computing system of claim 12 wherein the continuous radiation treatment session 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 computing system of claim 12 wherein the continuous radiation treatment session 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 computing system of claim 12 wherein the continuous radiation treatment session 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 computing system of claim 12 wherein the continuous radiation treatment session 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 computing system of claim 12 wherein the mid-treatment modification to the parameter is performed while a radiation beam is off.

19. The computing system of claim 1 wherein the the determination performed by the data processing subsystem comprises:

comparing the location indicated by the one or more location indications with a predefined volume; and

where the location indicated by the one or more location indications falls outside the predefined volume, presenting a warning.

20. The computing system of claim 19 wherein the warning is an audible warning.

21. The computing system of claim 19 wherein the warning is a visual warning.

22. The computing system of claim 19 wherein the warning is a redundant visual warning.

23. The computing system of claim 21 wherein the warning is displayed in a manner designed to warn a technician.

24. The computing system of claim 21 wherein the warning is displayed in a manner designed to warn the patient.

25. The computing system of claim 1 wherein the the determination performed by the data processing subsystem comprises:

comparing the location indicated by the one or more location indications with a predefined volume; and

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

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

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

28. The computing system of claim 1 wherein the received stream of digital location indications has a frequency of at least 20 hertz.

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

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

31. The computing system 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.

32. The computing system of claim 1 wherein the determination of whether the locations indicated by one or more location indications merits modifying a parameter of the continuous radiation treatment session is performed in substantially real-time relative to a measurement time associated with performing measurements upon which the location indications are based.

33. The computing system of claim 1 wherein the parameter is a beam parameter specifying activation or termination of a radiation beam.

34. The computing system of claim 1 wherein the information adequate to determine the distance from the target to the reference point comprises:

a directed distance in a first dimension from the target to the reference point;

a directed distance in a second dimension from the target to the reference point; and

a directed distance in a third dimension from the target to the reference point.

35. The computing system of claim 1 wherein the information adequate to determine the distance from the target to the reference point comprises a relative spatial location of the target from the reference point.

36. The computing system of claim 1 wherein the reference point is a machine isocenter.

37. A non-transitory computer-readable storage medium comprising computer-executable instructions to cause a computing system to perform a method for processing data while a target is undergoing radiation therapy, the computer-executable instructions comprising:

instructions to receive a digital location indication 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 indication being based upon locating the marker using non-ionizing radiation, wherein the digital location indication is received during a continuous radiation treatment session in substantially real-time during administration of radiation therapy;

instructions to, in response to receiving the location indication, in substantially real-time relative to the receipt of the location indication, determine whether the location indicated by the location indication merits modifying a parameter of the radiation therapy during the continuous radiation treatment session ; and

instructions to, in response to determining that the location indication merits modifying a parameter of the radiation therapy, modify the parameter of the radiation therapy during the continuous radiation treatment session in substantially real-time during administration of radiation therapy without interrupting the radiation therapy;

instructions to store the received location indication in an electronic record, wherein the electronic record includes time-indexed information correlating the received location indication with one or more treatment parameters of the radiation therapy during the continuous radiation treatment session, wherein the time-indexed information includes;

a measurement time at which the location indication was received; and

a displacement from the target to a reference point.

38. The physical computer-readable storage medium of claim 37 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.

39. The physical computer-readable storage medium of claim 37 wherein the location indicated by the one or more location indications merits modifying the beam parameter and a mid-treatment modification to the beam parameter is performed in accordance with the location indicated by the one or more location indications.

40. The physical computer-readable storage medium of claim 39 wherein the mid-treatment modification to the beam parameter is performed while a radiation beam corresponding to the radiation beam parameter is off.

41. The physical computer-readable storage medium of claim 37 wherein the beam parameter is a beam shape parameter specifying a cross-sectional shape of a radiation beam to be projected toward the target.

42. The physical computer-readable storage medium of claim 37 wherein the beam parameter is a beam direction parameter specifying a direction in which a radiation beam is projected toward the target.

43. The physical computer-readable storage medium of claim 37 wherein the beam parameter is a beam intensity parameter specifying a radiation intensity with which the target is to be treated.

44. The physical computer-readable storage medium of claim 37 wherein the beam parameter specifies activating or terminating a radiation beam.

45. The physical computer-readable storage medium of claim 37 wherein the beam parameter is a beam collimator parameter for controlling leaves of a multileaf collimator.

46. The physical computer-readable storage medium of claim 37 wherein the beam parameter is a modulation parameter for modulating beam intensisty.

47. The physical computer-readable storage medium of claim 37 wherein the beam parameter is a modulation parameter for controlling leaves of a multileaf collimator to effect intensity-modulated radiation therapy.

48. The physical computer-readable storage medium of claim 37 wherein the beam parameter is a beam rotation parameter specifying a rotation of a radiation beam about an axis.

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

using a data receiver subsystem that is configured to cause a processor of the computing system to receive a stream of digital location indications while a patient is undergoing a continuous radiation treatment session in substantially real-time during administration of radiation treatment, each location indication identifying a location of a target in the 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 a data processing subsystem that is configured to cause the processor of the computing system to determine whether the locations indicated by one or more location indications merits modifying a parameter of the continuous radiation treatment session, wherein the determination is in response to one or more location indications of the stream received during the continuous radiation treatment session, in substantially real-time relative to the receipt of the position indication by the data receiver subsystem;

using a modification subsystem that is configured to cause the processor of the computing system to modify the parameter during the continuous radiation treatment session in substantially real-time during administration of radiation treatment, without interrupting the continuous radiation treatment session, in response to the data processing subsystem determining that the locations indicated by one or more location indications merits modifying the parameter;

and a data storage subsystem that is configured to cause the processor of the computing system to store the received stream of digital location

reading a stored set of digital location indications each identifying a location of a target while undergoing radiation therapy taken in real-time during a continuous therapy session without interrupting the radiation therapy session; and

using the read digital location indications to review the provision of radiation therapy during the continuous therapy session, wherein reviewing the provision of radiation therapy during the continuous therapy session comprises verifying that the continuous therapy session is conducted in accordance with a continuous radiation therapy plan.

50. The method of claim 49 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.

51. The method of claim 49 wherein reviewing the provision of radiation therapy during the continuous therapy session comprises displaying an indication of the location of the target throughout the continuous therapy session.

52. The method of claim 49 wherein reviewing the provision of radiation therapy during the continuous therapy session comprises determining a portion of the continuous therapy session during which the target location was outside a predefined volume.

53. The method of claim 49 wherein reviewing the provision of radiation therapy during the continuous therapy session comprises identifying the smallest volume containing all of the target locations.

54. The method of claim 49, 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.