TREATMENT PLANNING APPARATUS AND PARTICLE THERAPY SYSTEM

• US 20120264998A1
• Filed: 04/17/2012
• Published: 10/18/2012
• Est. Priority Date: 04/18/2011
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: FUJII, Yusuke, FUJIMOTO, Rintaro, AKIYAMA, Hiroshi, FUJITAKA, Shinichiro, HIRAMOTO, Kazuo
• Granted Patent: US 8,847,179 B2
• Time in Patent Office: Days
• US Class Current: 600/1
• CPC Class Codes: A61N 2005/1087 Ions; Protons
• CPC Class Codes: A61N 5/1036 Leaf sequencing algorithms
• CPC Class Codes: A61N 5/1043 Scanning the radiation beam, e.g. spot scanning or raster scanning
• CPC Class Codes: A61N 5/1045 using a multi-leaf collimator, e.g. for intensity modulated radiation therapy or IMRT

Abstract

A charged particle beam reduces treatment time in the uniform scanning or in the conformal layer stacking irradiation. In the uniform scanning, an optimum charged particle beam scan path for uniformly irradiating a collimator aperture area is calculated. In the conformal layer stacking irradiation, an optimum charged particle beam scan path for uniformly irradiating a multi-leaf collimator aperture area of each layer for each of the layers obtained by partitioning the target volume is calculated. Alternatively, a minimum irradiation field size that covers the multi-leaf collimator aperture area of each layer is calculated, and a scan path corresponding to the irradiation field size, prestored in a memory of a particle therapy control apparatus, is selected. The charged particle beam scan path is optimally changed in the lateral directions in conformity with the collimator aperture area in the uniform scanning or in each layer in the conformal layer stacking irradiation.

Claims

1. A treatment planning apparatus for planning a uniform scan in which a dose distribution uniform in lateral directions is formed by scanning a charged particle beam with electromagnets, wherein:

the treatment planning apparatus comprises a treatment planning operation unit that calculates an optimum scan path in the lateral directions in consideration of a collimator aperture.

2. The treatment planning apparatus according to claim 1, wherein the scan path in the lateral directions is a raster scan path.

3. The treatment planning apparatus according to claim 1, wherein the scan path in the lateral directions is a line scan path.

4. A treatment planning apparatus for planning conformal layer stacking irradiation in which a target volume is partitioned into layers, a bolus for adjusting the dose distribution to the shape of the target volume is used, and each layer of the layer-partitioned target volume is successively irradiated with a charged particle beam while changing the irradiation field shape in lateral directions for each layer by using a multi-leaf collimator, wherein:

the treatment planning apparatus comprises a treatment planning operation unit that changes the scan path of the charged particle beam for each layer by calculating a multi-leaf collimator aperture area of each layer and calculating a minimum scan path of the charged particle beam suitable for the calculated aperture area.

6. The treatment planning apparatus according to claim 4, wherein the lateral irradiation of each layer is conducted by means of the raster scan.

7. The treatment planning apparatus according to claim 4, wherein the lateral irradiation of each layer is conducted by means of the zigzag scan.

8. The treatment planning apparatus according to claim 4, wherein the lateral irradiation of each layer is conducted by means of the circular wobbling.

9. The treatment planning apparatus according to claim 4, wherein the lateral irradiation of each layer is conducted by means of the spiral wobbling.

10. The treatment planning apparatus according to claim 4, wherein the lateral irradiation of each layer is conducted by means of the line scan.

5. A particle therapy system for conducting conformal layer stacking irradiation in which a target volume is partitioned into layers, a bolus for adjusting the dose distribution to the shape of the target volume is used, and each layer of the layer-partitioned target volume is successively irradiated with a charged particle beam while changing the irradiation field shape in lateral directions for each layer using a multi-leaf collimator, wherein:

the particle therapy system comprises;

a treatment planning apparatus that calculates a multi-leaf collimator aperture area of each layer and calculates an irradiation field size covering the calculated aperture area, and

a control apparatus that previously holds a plurality of scan paths corresponding to the calculated irradiation field sizes and changes the scan path of the charged particle beam for each layer based on the scan path corresponding to the calculated irradiation field size.

11. The particle therapy system according to claim 5, wherein the lateral irradiation of each layer is conducted by means of the raster scan.

12. The particle therapy system according to claim 5, wherein the lateral irradiation of each layer is conducted by means of the zigzag scan.

13. The particle therapy system according to claim 5, wherein the lateral the irradiation of each layer is conducted by means of the circular wobbling.

14. The particle therapy system according to claim 5, wherein the lateral irradiation of each layer is conducted by means of the spiral wobbling.

15. The particle therapy system according to claim 5, wherein the lateral irradiation of each layer is conducted by means of the line scan.