Radiation detector calibration

• US 10,881,880 B2
• Filed: 04/10/2020
• Issued: 01/05/2021
• Est. Priority Date: 04/23/2015
• Status: Active Grant

• Current Assignee: Sun Nuclear Corporation (American Capital Limited)
• Original Assignee: Sun Nuclear Corporation (American Capital Limited)
• Inventors: Ramezanzadeh Moghadam, Amir, Kozelka, Jakub
• Primary Examiner(s): Song, Hoon K
• Application Number:
  US16/846,227
• Publication Number:
  US 20200238104A1
• Time in Patent Office: 270 Days
• Field of Search: None
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61N 2005/1054 using a portal imaging system
• CPC Class Codes: A61N 5/1045 using a multi-leaf collimator, e.g. for intensity modulated radiation therapy or IMRT
• CPC Class Codes: A61N 5/1049 for verifying the position of the patient with respect to the radiation beam
• CPC Class Codes: A61N 5/1071 for verifying the dose delivered by the treatment plan
• CPC Class Codes: A61N 5/1075 for testing, calibrating, or quality assurance of the radiation treatment apparatus

Abstract

A computer program product, method, system and device that acquires, by a radiation detector, exit radiation measurement information during delivery of patient treatment. Patient anatomy information is also received and a radiation detector response calibration is determined utilizing at least the exit radiation measurement information, the patient anatomy information, and at least a portion of a radiation treatment plan.

Claims

1. A system comprising:

at least one programmable processor; and

a non-transitory machine-readable medium storing instructions which, when executed by the at least one programmable processor, cause the at least one programmable processor to perform operations comprising;

receiving at least a portion of a radiation treatment plan;

acquiring, by a radiation detector, exit radiation measurement information during delivery of patient treatment;

deriving a measured collimator profile from the exit radiation measurement information;

determining at least one estimated collimator profile from at least a portion of the radiation treatment plan and an approximate image start time and an approximate image end time; and

comparing the measured collimator profile with at least one estimated collimator profile to determine an image start time and an image end time.

2. The system of claim 1, wherein the radiation detector is an EPID.

3. The system of claim 1, wherein the measured collimator profile and/or the estimated collimator profile comprise a boundary of an aperture formed by leaves of the collimator.

4. The system of claim 1, the at least one programmable processor further configured to perform operations comprising determining the start and end times by at least determining a best match between the measured collimator profile and more than one estimated collimator profile to determine a best matched collimator profile.

5. The system of claim 4, the at least one programmable processor further configured to perform operations comprising determining the best match by at least minimizing the distance between boundaries of the estimated collimator profile and the measured collimator profile.

6. The system of claim 4, the at least one programmable processor further configured to perform operations comprising:

calculating a difference between the measured collimator profile and the best matched collimator profile; and

increasing, in response to the difference exceeding a predetermined value, a range of times for the image start time and the image end time used to calculate the more than one estimated collimator profiles.

7. The system of claim 1, wherein the image start time and image end time correspond to times from the radiation treatment plan.

8. The system of claim 1, the at least one programmable processor further configured to perform operations comprising determining a patient entrance fluence utilizing the portion of the radiation treatment plan and the image start time and image end time.

9. A computer program product comprising a non-transitory, machine-readable medium storing instructions which, when executed by at least one programmable processor, cause the at least one programmable processor to perform operations comprising:

receiving at least a portion of a radiation treatment plan;

acquiring, by a radiation detector, exit radiation measurement information during delivery of patient treatment;

deriving a measured collimator profile from the exit radiation measurement information;

determining at least one estimated collimator profile from at least a portion of the radiation treatment plan and an approximate image start time and an approximate image end time; and

comparing the measured collimator profile with at least one estimated collimator profile to determine an image start time and an image end time.

10. The computer program product of claim 9, wherein the radiation detector is an EPID.

11. The computer program product of claim 9, wherein the measured collimator profile and/or the estimated collimator profile comprise a boundary of an aperture formed by leaves of the collimator.

12. The computer program product of claim 9, the operations further comprising determining the start and end times by at least determining a best match between the measured collimator profile and more than one estimated collimator profile to determine a best matched collimator profile.

13. The computer program product of claim 12, the operations further comprising determining the best match by at least minimizing the distance between boundaries of the estimated collimator profile and the measured collimator profile.

14. The computer program product of claim 12, the operations further comprising:

calculating a difference between the measured collimator profile and the best matched collimator profile; and

increasing, in response to the difference exceeding a predetermined value, a range of times for the image start time and the image end time used to calculate the more than one estimated collimator profiles.

15. The computer program product of claim 9, wherein the image start time and image end time correspond to times from the radiation treatment plan.

16. The computer program product of claim 9, the at least one programmable processor further configured to perform operations comprising determining a patient entrance fluence utilizing the portion of the radiation treatment plan and the image start time and image end time.