METHOD AND DEVICE FOR DETERMINING A RADIOTHERAPY TREATMENT PLAN

• US 20130072743A1
• Filed: 03/13/2012
• Published: 03/21/2013
• Est. Priority Date: 03/17/2011
• Status: Active Grant

• Current Assignee: Siemens Healthineers AG (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Fieres, Johannes, Thilmann, Oliver
• Granted Patent: US 9,033,859 B2
• Time in Patent Office: Days
• US Class Current: 600/1
• CPC Class Codes: A61N 5/103 Treatment planning systems
• CPC Class Codes: A61N 5/1031 using a specific method of dose optimization

Abstract

A radiotherapy treatment plan for irradiation of an object to be irradiated is determined. The object to be irradiated includes a number of irradiation areas and the object to be irradiated is irradiated with a number of beams from different directions. The method includes determining a number of total dose conditions. One of the number of total dose conditions is assigned to a respective one of the number of irradiation areas. The method further includes determining a number of single beam dose conditions. One of the single dose conditions is assigned to a respective one of the number of beams and a respective one of the number of irradiation areas. The method also includes determining irradiation parameters for the number of beams as a function of the number of total dose conditions and the number of single beam dose conditions.

Claims

1. A method for determining a radiotherapy treatment plan for an irradiation of an object to be irradiated, wherein a number of irradiation regions are determined in the object to be irradiated, and wherein the object to be irradiated is irradiated with a number of beams from different directions, the method comprising:

determining a number of total dose conditions, wherein at least one of the number of total dose conditions is assigned to a respective one of the number of irradiation regions, and wherein each total dose condition defines a condition for the total radiation dose for the respective irradiation region;

determining a number of single beam dose conditions, wherein one of a number of single beam dose conditions is assigned to a respective one of the number of beams and a respective one of the number of irradiation regions, and wherein the single beam dose condition assigned to the respective beam defines a condition for a beam dose as a function of the beam for the respective irradiation region; and

determining irradiation parameters for the number of beams as a function of the number of total dose conditions and of the number of single beam dose conditions.

2. The method as claimed in claim 1, wherein determining the irradiation parameters for the number of beams comprises minimizing a target function F(p), where

3. The method as claimed in claim 1, wherein determining the number of total dose conditions comprises capturing a user input of the total dose condition for a respective one of the number of irradiation regions.

4. The method as claimed in claim 1, wherein determining the number of single beam dose conditions comprises capturing a user input of the single beam dose condition for a respective one of the number of beams and a respective one of the number of the irradiation regions.

5. The method as claimed in claim 1, wherein determining the number of single beam dose conditions comprises automatically determining the number of single beam dose conditions as a function of a predetermined beam homogeneity factor, wherein the beam homogeneity factor defines for one of the number of irradiation regions a maximum difference between radiation doses introduced by the number of beams into the respective one of the number of irradiation regions.

6. The method as claimed in claim 5, further comprises capturing a user input that specifies the beam homogeneity factor.

7. The method as claimed in claim 5, wherein the beam homogeneity factor comprises a fixed value.

8. The method as claimed in claim 5, further comprising capturing a user input of a beam homogeneity weighting, wherein determining the irradiation parameters comprises determining the irradiation parameters for each of the number of beams as a function of the number of total dose conditions, the number of single beam dose conditions, and the beam homogeneity weighting, and wherein the beam homogeneity weighting defines an importance of the single dose conditions in the determination of the irradiation parameters.

9. The method as claimed in claim 6, further comprising capturing a user input of a beam homogeneity weighting, wherein determining the irradiation parameters comprises determining the irradiation parameters for each of the number of beams as a function of the number of total dose conditions, the number of single beam dose conditions, and the beam homogeneity weighting, and wherein the beam homogeneity weighting defines an importance of the single dose conditions in the determination of the irradiation parameters.

10. The method as claimed in claim 8, wherein determining the irradiation parameters for the number of beams comprises minimizing a target function F(p), where

11. The method as claimed in claim 10, wherein the evaluation function F_i(p,HF) determined by the beam homogeneity factor HF_{for the beam} i is determined based on a predetermined minimum total dose level and a predetermined maximum total does level, and further comprising determining a dose evaluation function for the beam using a maximum dose level D_max,i, where D_max,i=D_max,tot*(1−

HF/B), and a minimum dose level D_min,i, where D_min,i=D_min,tot*HF/B, wherein B is the number of beams.

12. The method as claimed in claim 1, further comprising detecting a user input of a single beam weighting, wherein determining the irradiation parameters comprises a determining the irradiation parameters for each of the number of beams as a function of the number of total dose conditions, the number of single beam dose conditions, and the single beam weighting, and wherein the single beam weighting defines a relationship between the single beam dose conditions and the total dose conditions in the determination of the irradiation parameters.

13. The method as claimed in claim 12, with determining the irradiation parameters for the number of beams comprises minimizing a target function F(p), where

14. The method as claimed in claim 1, further comprising determining a number of beam-specific irradiation regions in the object to be irradiated, wherein the irradiation parameters for the number of beams are, for irradiation areas in which the beam-specific irradiation regions overlap, determined as a function of the total dose conditions, and for irradiation areas in which the beam-specific irradiation areas do not overlap, determined as a function of the single beam dose conditions.

15. The method as claimed in claim 1, wherein the total dose condition comprises a maximum dose, a minimum dose, a dose-volume histogram, an average dose, an equivalent uniform dose (EUD), a biological target value, or a dose homogeneity.

16. The method as claimed in claim 3, wherein the total dose condition comprises a maximum dose, a minimum dose, a dose-volume histogram, an average dose, an equivalent uniform dose (EUD), a biological target value, or a dose homogeneity.

17. The method as claimed in claim 1, wherein the single beam dose condition comprises a maximum dose, a minimum dose, an average dose, or a dose homogeneity.

18. The method as claimed in claim 4, wherein the single beam dose condition comprises a maximum dose, a minimum dose, an average dose, or a dose homogeneity.

19. A device configured to determine a radiotherapy treatment plan for an irradiation of an object to be irradiated, wherein the object to be irradiated includes a number of irradiation areas, and wherein the object to be irradiated is irradiated with a number of beams from different directions, the device comprising:

a first determination unit configured to determine a number of total dose conditions, wherein at least one of the number of total dose conditions is assigned to each respective one of the number of irradiation areas, and wherein the total dose condition assigned to the respective irradiation area defines a condition for the total beam dose for the respective irradiation area;

a second determination unit configured to determine a number of single beam dose conditions, wherein at least one of the number of single beam dose conditions is assigned to a respective one of the number of beams and a respective one of the number of irradiation areas, and wherein the single beam dose condition assigned to the respective beam defines a condition for the radiation dose based on the beam for the respective irradiation area, and

a processing unit configured to define irradiation parameters for the number of beams as a function of the number of total dose conditions and the number of single beam dose conditions.

20. The device as claimed in claim 19, wherein the device is part of a particle therapy system.

21. A computer program product comprising a program operable to be loaded directly into a memory of a programmable processing unit of a device for determining a radiotherapy treatment plan for irradiation of an object to be irradiated, wherein the object to be irradiated includes a number of irradiation areas, and wherein the object to be irradiated is irradiated with a number of beams from different directions, the computer program product comprising instructions for causing the program to:

determine a number of total dose conditions, wherein at least one of the number of total dose conditions is assigned to a respective one of the number of irradiation regions, and wherein each total dose condition defines a condition for the total radiation dose for the respective irradiation region;

determine a number of single beam dose conditions, wherein one of a number of single beam dose conditions is assigned to a respective one of the number of beams and a respective one of the number of irradiation regions, and wherein the single beam dose condition assigned to the respective beam defines a condition for a beam dose as a function of the beam for the respective irradiation region; and

determine irradiation parameters for the number of beams as a function of the number of total dose conditions and of the number of single beam dose conditions.

22. In a non-transitory computer-readable data medium having stored thereon program instructions for determining a radiotherapy treatment plan for irradiation of an object to be irradiated, wherein the object to be irradiated includes a number of irradiation areas, and wherein the object to be irradiated is irradiated with a number of beams from different directions, wherein execution of the program instructions by a processing unit of a device causes the processing unit to carry out the steps of:

determining a number of total dose conditions, wherein at least one of the number of total dose conditions is assigned to a respective one of the number of irradiation regions, and wherein each total dose condition defines a condition for the total radiation dose for the respective irradiation region;

determining a number of single beam dose conditions, wherein one of a number of single beam dose conditions is assigned to a respective one of the number of beams and a respective one of the number of irradiation regions, and wherein the single beam dose condition assigned to the respective beam defines a condition for a beam dose as a function of the beam for the respective irradiation region; and

determining irradiation parameters for the number of beams as a function of the number of total dose conditions and of the number of single beam dose conditions.