Radiation treatment planning based on dose rate

1. A computer system, comprising:

a processor; and

memory coupled to the processor and comprising instructions that, when executed, cause the processor to perform a method of radiation treatment planning, the method comprising:

accessing information in the memory, the information comprising an irradiation time received by a target volume;

generating an irradiation time-volume histogram for the target volume, wherein the irradiation time-volume histogram indicates a percentage of the target volume that is irradiated for a length of time;

storing the irradiation time-volume histogram in the memory; and

using the irradiation time-volume histogram to generate a radiation treatment plan for treating the target volume.

2. The computer system of claim 1 , wherein the target volume comprises a plurality of sub-volumes, wherein an irradiation time is determined for each sub-volume of the plurality of sub-volumes, and wherein the irradiation time for said each sub-volume is used to generate the irradiation time-volume histogram.

3. The computer system of claim 1 , wherein the irradiation time is determined using parameters comprising a number of irradiations of the target volume, a duration of each of the irradiations, and a dose deposited in each of the irradiations.

4. The computer system of claim 3 , wherein the parameters further comprise: directions of beams to be directed into the target volume, and beam energies for each of the beams.

5. The computer system of claim 4 , wherein the beams comprise a type of beam selected from the group consisting of: proton; electron; photon; atom nuclei; and ion.

6. The computer system of claim 3 , wherein the parameters further comprise: a period of time during which the irradiations are applied, and an interval of time between each period of irradiations.

7. The computer system of claim 3 , wherein the method further comprises adjusting the values of the parameters until objectives associated with the radiation treatment plan are satisfied.

8. The computer system of claim 3 , wherein the target volume comprises a plurality of sub-volumes, wherein the parameters comprise a number of irradiations for each of the sub-volumes, a duration of each of the irradiations for each of the sub-volumes, and a dose deposited in each of the irradiations for each of the sub-volumes, and wherein an irradiation time is determined for each of the sub-volumes based on the parameters.

9. The computer system of claim 1 , wherein the method further comprises determining isolines of dose rates relative to the target volume based on the irradiation time-volume histogram.

10. The computer system of claim 1 , wherein the target volume comprises tumor tissue and healthy tissue adjacent to the tumor tissue, and wherein the irradiation time-volume histogram indicates a percentage of the tumor tissue that is irradiated for a length of time and a percentage of the healthy tissue that is irradiated for a length of time.

11. The computer system of claim 1 , wherein the method further comprises:

generating a dose-rate volume histogram for the target volume, wherein the dose-rate volume histogram indicates a percentage of the target volume that receives the dose rate;

storing the dose-rate volume histogram in the memory; and

using the dose-rate volume histogram to generate the radiation treatment plan.

12. A non-transitory computer-readable storage medium having computer-executable instructions for causing a computer system to perform a method of generating a radiation treatment plan, the method comprising:

accessing information that identifies a target volume comprising a representation of tumor tissue and of healthy tissue proximate to the tumor tissue;

accessing parameters comprising a number of irradiations of the target volume, a duration of each of the irradiations, and a dose deposited in each of the irradiations;

generating an irradiation time-volume histogram for the target volume using an irradiation time determined using the parameters, wherein the irradiation time-volume histogram indicates a percentage of the target volume that is irradiated for a length of time; and

storing the irradiation time-volume histogram in the memory for use in generating the radiation treatment plan.

13. The non-transitory computer-readable storage medium of claim 12 , wherein the target volume comprises a plurality of sub-volumes, wherein the parameters comprise a number of irradiations for each of the sub-volumes, a duration of each of the irradiations for each of the sub-volumes, and a dose deposited in each of the irradiations for each of the sub-volumes, and wherein an irradiation time is determined for each of the sub-volumes based on the parameters, wherein the irradiation time for each of the sub-volumes is used to generate the irradiation time-volume histogram.

14. The non-transitory computer-readable storage medium of claim 12 , wherein the parameters further comprise: directions of beams to be directed into the target volume, and beam energies for each of the beams.

15. The non-transitory computer-readable storage medium of claim 12 , wherein the parameters further comprise: a period of time during which the irradiations are applied, and an interval of time between each period of irradiations.

16. A non-transitory computer-readable storage medium having computer-executable instructions for causing a computer system to perform a method of generating a radiation treatment plan, the method comprising:

accessing an irradiation time-volume histogram for a target volume, wherein the irradiation time-volume histogram indicates irradiation times and percentages of the target volume that are irradiated for a respective length of time, and wherein the irradiation time-volume histogram is determined using values for parameters that affect irradiation time; and

including the values for the parameters in the radiation treatment plan when, based on the irradiation time-volume histogram, a percentage of the target volume that is irradiated for a length of time that is below an irradiation time threshold value is above a percentage threshold value.

17. The non-transitory computer-readable storage medium of claim 16 , wherein the parameters comprise: a number of irradiations of the target volume, a duration of each of the irradiations, and a dose deposited in each of the irradiations.

18. The non-transitory computer-readable storage medium of claim 17 , wherein the parameters further comprise: directions of beams to be directed into the target volume, and beam energies for each of the beams.

19. The non-transitory computer-readable storage medium of claim 17 , wherein the parameters further comprise: a period of time during which the irradiations are applied, and an interval of time between each period of irradiations.

20. The non-transitory computer-readable storage medium of claim 16 , wherein the target volume comprises a plurality of sub-volumes, wherein the parameters comprise a number of irradiations for each of the sub-volumes, a duration of each of the irradiations for each of the sub-volumes, and a dose deposited in each of the irradiations for each of the sub-volumes, and wherein an irradiation time is determined for each of the sub-volumes based on the parameters, wherein the irradiation time for each of the sub-volumes is used to generate the irradiation time-volume histogram.

21. The non-transitory computer-readable storage medium of claim 16 , wherein the method further comprises adjusting the values of the parameters until the percentage of the target volume that is irradiated for a length of time that is below the irradiation time threshold value is above the percentage threshold value.