Compensation for target rotation using a collimation system

Abstract

The method includes detecting a potential setup error in a radiation treatment delivery session of a radiation treatment delivery system, the setup error corresponding to a change in a current position of the treatment target relative to a prior position of the treatment target, the change including a rotation relative to the prior position of the treatment target. The method further includes modifying, by a processing device, one or more planned leaf positions of a multi-leaf collimator (MLC) of a linear accelerator (LINAC) of the radiation treatment delivery system to compensate for the potential setup error corresponding to the rotation of the prior position of the treatment target. [Selected figure] Figure 2

Claims

1. A helical radiotherapy delivery system that projects radiotherapy beams onto a treatment target area of ​​a patient sequentially from two or more different angles while rotating a radiation source around the patient, A binary multi-leaf collimator (MLC) for shaping the aforementioned radiation therapy beam, A sinogram for operating the aforementioned binary multileaf collimator (MLC), Memory and A processing device operationally connected to the aforementioned memory, Equipped with, The binary multi-leaf collimator (MLC) has a plurality of parallel leaves that change between open and closed leaf positions, and controls the radiation fluence of the radiotherapy beam by the leaf position and leaf opening time of each of these leaves. The sinogram represents the planning pattern of each leaf position of the plurality of leaves when the binary multi-leaf collimator (MLC) is in operation, expressed by the order of the leaf arrangement and the order of projection by the system, and the radiation fluence of the radiotherapy beam is determined by associating the leaf opening time corresponding to the treatment target region with each expressed leaf position. The processing device is configured to detect potential setup errors in a radiotherapy delivery session, the setup errors corresponding to a change in the current position of the treatment target relative to the pre-position of the treatment target planned in the sinogram, the change including rotation of the treatment target relative to the pre-position, Furthermore, in order to compensate for the potential setup error corresponding to the rotation of the therapeutic target relative to its pre-position, the binary multi-leaf collimator (MLC) is configured to correct one or more leaf positions and one or more leaf open times in the sinogram. In addition, the processing device modifies one or more leaf positions and one or more leaf release times in the sinogram of the binary multi-leaf collimator (MLC), In the sinogram, a shift pattern is generated that modifies the plan pattern by shifting the leaf position plan pattern corresponding to the pre-position of the treatment target by one or more leaves in the leaf arrangement direction so that it corresponds to the current position of the treatment target. Furthermore, a radiotherapy delivery system that modifies the leaf opening time associated with each leaf position included in this shift pattern to correspond to the current position of the treatment target.

2. The aforementioned changes further correspond to multiple rotational components of the therapeutic target relative to the prior position, The processing device further, The position of the radiation source of the radiotherapy delivery system is corrected to compensate for the potential setup error corresponding to at least one of the plurality of rotational components of the treatment target relative to the pre-position, and further The system according to claim 1, wherein one or more leaf positions and one or more leaf opening times in the sinogram of the binary multileaf collimator (MLC) are corrected to compensate for at least one remaining component of the rotation of the therapeutic target relative to the pre-position.

3. The system according to claim 1, wherein the treatment bed of the radiation therapy delivery system moves continuously during the radiation therapy delivery session.

4. The system according to claim 1, wherein the treatment bed of the radiation therapy delivery system remains stationary while the binary multileaf collimator (MLC) corrects one or more leaf positions and one or more leaf opening times in the sinogram.

5. The system according to claim 1, wherein the aforementioned pre-position is identified within the treatment planning image.

6. The system according to claim 1, wherein the current position is identified in a volumetric X-ray image.

7. The current position is identified within the MR image, according to claim 1.

8. The system according to claim 1, wherein the current position is identified within at least one two-dimensional X-ray image.

9. The system according to claim 1, wherein the current position is determined by optical tracking of externally visible features.

10. A non-temporary computer-readable medium in which instructions for causing a processing device of a radiation therapy delivery system to perform a predetermined process are stored, The aforementioned radiation therapy delivery system is A helical radiotherapy delivery system that projects radiotherapy beams onto the treatment target area of ​​a patient sequentially from two or more different angles while rotating a radiation source around the patient, A binary multi-leaf collimator (MLC) for shaping the aforementioned radiation therapy beam, A sinogram for operating the aforementioned binary multileaf collimator (MLC), Memory and A processing device operationally connected to the aforementioned memory, Equipped with, The binary multi-leaf collimator (MLC) has a plurality of parallel leaves that change between open and closed leaf positions, and controls the radiation fluence of the radiotherapy beam by the leaf position and leaf opening time of each of these leaves. The sinogram represents the planning pattern of each leaf position of the plurality of leaves when the binary multi-leaf collimator (MLC) is in operation, expressed by the order of the leaf arrangement and the order of projection by the system, and the radiation fluence of the radiotherapy beam is determined by associating the leaf opening time corresponding to the treatment target region with each expressed leaf position. When the aforementioned instruction is executed by the processing device of the radiation therapy delivery system, the processing device will: The system is designed to detect potential setup errors in a radiotherapy delivery session, the setup errors corresponding to changes in the current position of the treatment target relative to the pre-position of the treatment target planned in the sinogram, the changes including rotation of the treatment target relative to the pre-position. Furthermore, in order to compensate for the potential setup error corresponding to the rotation of the treatment target relative to the pre-position, the binary multi-leaf collimator (MLC) is configured to correct one or more leaf positions and one or more leaf opening times in the sinogram. In addition, the instruction is given to the processing device, In order to correct one or more leaf positions and one or more leaf opening times in the sinogram of the binary multi-leaf collimator (MLC), In the sinogram, a shift pattern is generated that modifies the plan pattern by shifting the leaf position plan pattern corresponding to the pre-position of the treatment target by one or more leaves in the leaf arrangement direction so that it corresponds to the current position of the treatment target. Furthermore, a non-temporary computer-readable medium that modifies the leaf release time associated with each leaf position included in this shift pattern to correspond to the current position of the treatment target.

11. The non-temporary computer-readable medium according to claim 10, wherein the processing device is configured to continuously move the treatment bed of the radiotherapy delivery system during a radiotherapy delivery session.

12. The non-temporary computer-readable medium according to claim 10, wherein the treatment bed of the radiation therapy delivery system remains stationary while correcting one or more leaf positions and one or more leaf opening times in the sinogram of the binary multi-leaf collimator (MLC).

13. The non-temporary computer-readable medium according to claim 10, wherein the pre-position is identified in a pre-treatment planning image and the current position is identified in a patient setup image.

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