System and method of calculating dose uncertainty

• US 8,363,784 B2
• Filed: 08/28/2009
• Issued: 01/29/2013
• Est. Priority Date: 08/28/2008
• Status: Active Grant

• Current Assignee: Accuray Incorporated
• Original Assignee: TomoTherapy Incorporated (Accuray Incorporated)
• Inventors: Sobering, Geoff, Schnarr, Eric, Ruchala, Kenneth J.
• Primary Examiner(s): SONG, HOON K
• Application Number:
  US12/550,184
• Publication Number:
  US 20100054413A1
• Time in Patent Office: 1,250 Days
• Field of Search: 378 64- 65
• US Class Current: 378/65
• CPC Class Codes: A61N 5/1031 using a specific method of dose optimization
• CPC Class Codes: G16H 20/40 relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture
• CPC Class Codes: G16H 40/63 for local operation

Abstract

A dose calculation tool operable to generate a variance map that represents a dose uncertainty. The variance map illustrates on a point-by-point basis where high uncertainty in the dose may exist and where low uncertainty in the dose may exist. The dose uncertainty is a result of an error in one or more data parameters related to a delivery parameter or a computational parameter.

Claims

1. A method of evaluating dosimetric uncertainties for a radiation delivery, the radiation delivery performed pursuant to a treatment plan and the treatment plan comprising machine delivery instructions, the method comprising:

identifying a data parameter for the radiation delivery device;

identifying uncertainty in the data parameter related to the delivery instructions;

generating a dose map using the delivery instructions and a dose calculation module; and

generating a statistical uncertainty map utilizing the uncertainty in the data parameter, the delivery instructions, and the dose calculation module, the statistical uncertainty map representing an uncertainty indication in the dose map related to the uncertainty in the data parameter.

2. The method of claim 1 further comprising optimizing the treatment plan for the patient to reduce the uncertainty indication.

3. The method of claim 2 wherein optimizing the treatment plan includes using the uncertainty indication for the data parameter as a constraint when determining a setting of the data parameter.

4. The method of claim 2 wherein optimizing the treatment plan includes reducing reliance on a particular leaf of a multi-leaf collimator that has a greater uncertainty.

5. The method of claim 2 wherein optimizing the treatment plan includes adjusting an isocenter of the treatment plan to reduce impact of uncertainties due to one of multi-leaf collimator position and jaw position.

6. The method of claim 2 wherein optimizing the treatment plan includes adjusting a fraction of leaf open time in projections to reduce uncertainties in leaf timing.

7. The method of claim 2 wherein optimizing the treatment plan includes reducing the treatment plan'"'"'s dependence on gantry angles that have higher radiation delivery device output uncertainty or shoot through regions of space that are affected by couch top position uncertainty.

8. The method of claim 2 wherein optimizing the treatment plan includes reducing the uncertainty indication for a particular area in the patient.

9. The method of claim 2 further comprising evaluating deliverability of the optimized treatment plan.

10. The method of claim 2 wherein optimizing the treatment plan includes selecting a different radiation delivery device to deliver the treatment plan to the patient.

11. The method of claim 1 further comprising generating a plurality of treatment plans and selecting one of the treatment plans to deliver to the patient based on the statistical uncertainty map.

12. The method of claim 1 wherein the data parameter is related to a delivery parameter of the radiation delivery device.

13. The method of claim 1 wherein the data parameter includes a combination of multiple single data parameters.

14. The method of claim 1 wherein the data parameter is fluence.

15. The method of claim 1 wherein the data parameter is linac output.

16. The method of claim 1 wherein the data parameter is leaf timing.

17. The method of claim 1 wherein the data parameter is jaw position.

18. The method of claim 1 wherein the data parameter is spectral changes in attenuation/energy components of a radiation beam.

19. The method of claim 1 wherein the data parameter is couch position.

20. The method of claim 1 wherein the data parameter is gantry position.

21. The method of claim 1 wherein the data parameter is related to a modeling parameter of the radiation delivery device.

22. The method of claim 1 wherein the data parameter is one of leaf size and shape.

23. The method of claim 1 wherein the data parameter is jaw shape.

24. The method of claim 1 wherein the data parameter is related to tongue and groove information of two adjacent leaves.

25. The method of claim 1 wherein the data parameter is source-to-axis distance.

26. The method of claim 1 wherein the data parameter is related to a change in beam shape.

27. The method of claim 1 further comprising generating an alert when the statistical uncertainty map indicates that the uncertainty indication in the dose exceeds a predetermined threshold.

28. The method of claim 1 wherein the radiation delivery device delivers photon-based radiation therapy.

29. The method of claim 1 wherein the radiation delivery device delivers ion-based or particle-based radiation therapy.