System and method for motion adaptive optimization for radiation therapy delivery

• US 8,467,497 B2
• Filed: 03/05/2009
• Issued: 06/18/2013
• Est. Priority Date: 10/25/2007
• Status: Active Grant

• Current Assignee: TomoTherapy Incorporated (Accuray Incorporated)
• Original Assignee: TomoTherapy Incorporated (Accuray Incorporated)
• Inventors: Lu, Weiguo, Chen, Mingli, Chen, Quan, Ruchala, Kenneth J., Olivera, Gustavo H.
• Primary Examiner(s): Midkiff, Anastasia
• Application Number:
  US12/398,869
• Publication Number:
  US 20090252291A1
• Time in Patent Office: 1,566 Days
• Field of Search: 378/64, 378/65, 378/68, 378/69, 378/210, 378/901, 600/1, 600427-429, 607/100, 604/20, 128/605
• US Class Current: 378/65
• CPC Class Codes: A61N 5/1037 taking into account the movement of the target, e.g. 4D-image based planning
• CPC Class Codes: A61N 5/1049 for verifying the position of the patient with respect to the radiation beam
• CPC Class Codes: A61N 5/1067 in real time, i.e. during treatment

Abstract

A system and method of optimizing delivery of a radiation therapy treatment. The system optimizes treatment delivery in real-time to take into account a variety of factors, such as patient anatomical and physiological changes (e.g., respiration and other movement, etc.), and machine configuration changes (e.g., beam output factors, couch error, leaf error, etc.).

Claims

1. A method of delivering a radiation therapy treatment, the method comprising:

generating a treatment plan for a patient, the treatment plan including a plurality of projections;

positioning the patient to receive radiation from a radiation source based on the treatment plan;

monitoring machine parameters during delivery of at least a portion of the plurality of projections in substantially real-time, the monitoring including analyzing information regarding the machine parameters and how the parameters affect dose delivered to the patient;

during delivery of at least a portion of the plurality of projections, calculating an accumulated radiation dose delivered to the patient in substantially real-time;

during delivery of at least a portion of the plurality of projections, optimizing at least a portion of the plurality of projections yet to be delivered to the patient in substantially real-time to incorporate the analyzed information from the monitored machine parameters and the accumulated radiation dose; and

delivering at least a portion of the plurality of projections yet to be delivered to the patient as optimized.

2. The method of delivering a radiation therapy treatment of claim 1 wherein accumulating the amount of radiation dose delivered to the patient includes using dose calculations on a 4D representation of the patient.

3. The method of delivering a radiation therapy treatment of claim 1 further comprising estimating an amount of radiation dose to be delivered to the patient in a future projection.

4. The method of delivering a radiation therapy treatment of claim 3 further comprising adjusting the treatment plan based on the estimated amount of radiation dose to be delivered to the patient in the future projection and the predicted position of a patient target during the future projection.

5. The method of delivering a radiation therapy treatment of claim 1, wherein calculating the accumulated radiation dose incorporates information relating to at least one of delivery instructions, delivery error detection and patient motion detection.

6. The method of delivering a radiation therapy treatment of claim 1, wherein calculating the accumulated radiation dose includes accumulating current dose plus previous dose delivered plus future dose to be delivered so that the optimized plurality of projections best matches or improves the planned dose.

7. The method of delivering a radiation therapy treatment of claim 1, wherein calculating the accumulated radiation dose incorporates real-time modification of treatments.

8. The method of delivering a radiation therapy treatment of claim 1, wherein optimizing at least a portion of the plurality of projections yet to be delivered to the patient includes optimizing an amount of radiation dose to be delivered in one of the plurality of projections to compensate for accumulated delivery errors that occurred in previous projections.

9. The method of delivering a radiation therapy treatment of claim 8 wherein the accumulated delivery errors are based on the calculated accumulated radiation dose, an estimated radiation dose to be delivered in future projections, and a predicted configuration of the patient during a next projection.

10. The method of delivering a radiation therapy treatment of claim 8 wherein the accumulated delivery errors include delivery errors from previous fractions.

11. The method of delivering a radiation therapy treatment of claim 8, wherein the accumulated delivery errors include linear accelerator output factor variations.

12. The method of delivering a radiation therapy treatment of claim 8, wherein the accumulated delivery errors include MLC leaf position errors.

13. The method of delivering a radiation therapy treatment of claim 8, wherein the accumulated delivery errors include one of linac position errors, couch position errors, jaw position errors, and compensator errors.

14. The method of delivering a radiation therapy treatment of claim 8, wherein the accumulated delivery errors are compensated in subsequent treatment delivery.

15. The method of delivering a radiation therapy treatment of claim 1 wherein optimizing at least a portion of the plurality of projections yet to be delivered to the patient incorporates changes to the treatment plan via a closed feedback loop.

16. The method of delivering a radiation therapy treatment of claim 1 further comprising monitoring changes to the patient in substantially real-time.

17. The method of delivering a radiation therapy treatment of claim 16, wherein monitoring changes to the patient in substantially real-time includes detection of patient breathing phases.

18. The method of delivering a radiation therapy treatment of claim 16, wherein monitoring changes to the patient in substantially real-time includes detection of tumor motion or tumor deformation.

19. The method of delivering a radiation therapy treatment of claim 16, wherein monitoring changes to the patient in substantially real-time includes prediction of patient breathing phases.

20. The method of delivering a radiation therapy treatment of claim 16, wherein monitoring changes to the patient in substantially real-time includes prediction of tumor motion or tumor deformation.

21. The method of delivering a radiation therapy treatment of claim 16, wherein optimizing at least a portion of the plurality of projections yet to be delivered to the patient in substantially real-time comprises predicting patient changes.

22. The method of delivering a radiation therapy treatment of claim 1, wherein optimizing at least a portion of the plurality of projections yet to be delivered to the patient in substantially real-time comprises predicting machine parameters.

23. The method of delivering a radiation therapy treatment of claim 22, wherein the prediction is based upon an a priori model about machine parameters.

24. The method of delivering a radiation therapy treatment of claim 22, wherein the prediction is based on a dynamic model about machine parameters.

25. The method of delivering a radiation therapy treatment of claim 1, wherein optimizing at least a portion of the plurality of projections yet to be delivered to the patient in substantially real-time includes utilizing dynamic programming for optimization of treatment delivery instructions.

28. The method of claim 1, wherein optimizing at least a portion of the plurality of projections yet to be delivered to the patient includes optimizing an open time of a plurality of leaves of a multi-collimator for at least a portion of the plurality of projections yet to be delivered to the patient in substantially real-time.

26. A method of delivering a radiation therapy treatment, the method comprising:

generating a treatment plan for a patient, the treatment plan including a plurality of projections;

positioning the patient to receive radiation from a radiation source based on the treatment plan;

monitoring machine parameters during delivery of at least a portion of the plurality of projections in substantially real-time, the monitoring including analyzing information regarding the machine parameters and how the parameters affect dose delivered to the patient;

monitoring changes to the patient during delivery of at least a portion of the plurality of projections in substantially real-time, the monitoring including analyzing information regarding the patient changes and how the changes affect dose delivered to the patient;

during delivery of at least a portion of the plurality of projections, calculating an accumulated radiation dose delivered to the patient in substantially real-time;

during delivery of at least a portion of the plurality of projections, optimizing at least a portion of the plurality of projections yet to be delivered to the patient in substantially real-time to incorporate the analyzed information from the monitored machine parameters, the monitored changes to the patient, and the accumulated radiation dose; and

delivering at least a portion of the plurality of projections yet to be delivered to the patient as optimized.

29. The method of claim 26, wherein optimizing at least a portion of the plurality of projections yet to be delivered to the patient includes optimizing an open time of a plurality of leaves of a multi-collimator for at least a portion of the plurality of projections yet to be delivered to the patient in substantially real-time.

27. A method of delivering a radiation therapy treatment, the method comprising:

generating a treatment plan for a patient, the treatment plan including a plurality of projections;

positioning the patient to receive radiation from a radiation source based on the treatment plan;

monitoring machine parameters during delivery of at least a portion of the plurality of projections in substantially real-time, the monitoring including analyzing information regarding the machine parameters and how the parameters affect dose delivered to the patient;

during delivery of at least a portion of the plurality of projections, calculating an amount of accumulated radiation dose delivered to the patient in substantially real-time;

during delivery of at least a portion of the plurality of projections, optimizing at least a portion of the plurality of projections yet to be delivered to the patient in substantially real-time to incorporate the analyzed information from the monitored machine parameters and the accumulated radiation dose, the optimizing including predicting machine parameters; and

delivering at least a portion of the plurality of projections yet to be delivered to the patient as optimized.

30. The method of claim 27, wherein optimizing at least a portion of the plurality of projections yet to be delivered to the patient includes optimizing an open time of a plurality of leaves of a multi-collimator for at least a portion of the plurality of projections yet to be delivered to the patient in substantially real-time.