METHOD FOR EVALUATING RADIATION MODEL DATA IN PARTICLE BEAM RADIATION APPLICATIONS

• US 20120056109A1
• Filed: 01/08/2010
• Published: 03/08/2012
• Est. Priority Date: 03/17/2009
• Status: Active Grant

• Current Assignee: Paul Scherrer-Institut (Schweizerische Eidgenossenschaft)
• Original Assignee: Paul Scherrer-Institut (Schweizerische Eidgenossenschaft)
• Inventors: Lomax, Antony
• Granted Patent: US 8,461,559 B2
• Time in Patent Office: Days
• US Class Current: 250/492.3
• CPC Class Codes: A61N 2005/1087 Ions; Protons
• CPC Class Codes: A61N 5/1031 using a specific method of dose optimization
• CPC Class Codes: A61N 5/1048 Monitoring, verifying, controlling systems and methods

Abstract

A method for evaluating radiation model data in particle beam radiation applications, in particular in proton beam therapy of a determined target volume of malignant tissue within a patient, includes the following steps: a) gaining diagnostic data for a determined target volume to be irradiated; b) calculating a particle range in the predetermined target volume based on the diagnostic data for the determined target volume; c) designing a radiation model with particle beam characteristics based on the calculated particle range and optionally on a calculated dose depth distribution; d) applying a single pencil beam shot to the determined target volume at an elevated beam energy as compared to the particle beam characteristics of the radiation model; e) measuring the beam range of the single pencil beam shot downstream of the determined target volume; and f) comparing the measured beam range to a reference beam range calculated on the basis of the radiation model.

Claims

1-6. -6. (canceled)

7. A method of evaluating radiation model data in a particle beam radiation application, the method which comprises

a) gaining diagnostic data for a determined target volume to be irradiated;

b) calculating a particle range in a predetermined target volume based on the diagnostic data for the determined target volume;

c) designing a radiation model having particle beam characteristics based on the calculated particle range and optionally on a calculated dose depth distribution;

d) applying a single pencil beam shot to the determined target volume at an elevated beam energy, elevated in comparison with the particle beam characteristics of the radiation model;

e) measuring a beam range of the single pencil beam shot downstream of the determined target volume; and

f) comparing the measured beam range to a reference beam range calculated on the basis of the radiation model.

8. The method according to claim 7, wherein the particle beam radiation application is a proton beam therapy of a determined target volume of malignant tissue within a patient.

9. The method according to claim 7, which comprises calculating the particle range on the basis of a calibration curve converting CT Hounsfield Units to particle stopping power.

10. The method according to claim 9, which comprises using a result of a comparison in step f) to amend the calibration curve in case the result exceeds a predefined threshold.

11. The method according to claim 7, which comprises determining a location of an entry point of the single pencil beam shot in dependence on the inhomogeneities of the determined volume.

12. The method according to claim 7, wherein the step of measuring the beam range includes measuring one or both of a Bragg peak and its fall-off of the single pencil beam shot.

13. The method according to claim 12, wherein the step of measuring the beam range is performed with a spatial resolution of less than 10 mm.

14. The method according to claim 13, which comprises measuring the beam range with a spatial resolution of less than 5 mm.