Phantom for intensity modulated radiation therapy

• US 20040228435A1
• Filed: 05/14/2003
• Published: 11/18/2004
• Est. Priority Date: 05/14/2003
• Status: Abandoned Application

• Current Assignee: M.D. Anderson Cancer Center (University of Texas System)
• Original Assignee: M.D. Anderson Cancer Center (University of Texas System)
• Inventors: Russell, Kevin J.
• Application Number:
  US10/438,303
• Publication Number:
  US 20040228435A1
• Time in Patent Office: Days
• US Class Current: 378/18
• CPC Class Codes: A61B 6/583 using calibration phantoms
• CPC Class Codes: A61N 2005/1076 using a dummy object placed in the radiation field, e.g. phantom
• CPC Class Codes: A61N 5/1048 Monitoring, verifying, controlling systems and methods
• CPC Class Codes: A61N 5/1075 for testing, calibrating, or quality assurance of the radiation treatment apparatus

Abstract

Disclosed is a phantom for dose verification for intensity-modulated radiation therapy having a base of substantially tissue-equivalent material and a two-dimensional array of cavities formed in the base with each the cavities being configured and dimensioned to receive a radiation detector.

Claims

1. A phantom for dose verification in intensity-modulated radiation therapy, comprising:

a base of substantially tissue-equivalent material; and

a two-dimensional array of cavities formed in said base with each said cavity being configured and dimensioned to receive a radiation detector.

2. The phantom according to claim 1, wherein each dimension of said two-dimensional array has an odd number of said cavities so as to define a center cavity.

3. The phantom according to claim 2, further including:

at least one radiation detector being disposed in one of said cavities, and

a plug of substantially tissue-equivalent material being disposed in all of said cavities not containing one of said radiation detectors.

4. The phantom according to claim 3, wherein said cavities are spaced apart from each other by no more than 3 centimeters.

5. The phantom according to claim 3, wherein said array of cavities is dimensioned to be equal to or greater than a field of treatment used in the intensity-modulated radiation therapy.

6. A radiation therapy device for intensity-modulated radiation therapy, comprising:

a radiation source providing a radiation beam;

a collimator having an opening for shaping said radiation beam;

a phantom for dose verification of said radiation beam;

said phantom having a base of substantially tissue-equivalent material and a two-dimensional array of cavities formed in said base, with each said cavity being configured and dimensioned to receive a radiation detector; and

said opening of said collimator 38 having a cross section dimensioned to be equal to or less than a cross section of said two-dimensional array of cavities.

7. The radiation therapy device in accordance with claim 6, wherein said cross section of said opening is substantially parallel to said section of said two-dimensional array and both said cross sections are substantially perpendicular to a center axis of said radiation beam.

8. The radiation therapy device according to claim 6, wherein each dimension of said two-dimensional array has an odd number of said cavities so as to define a center cavity.

9. The radiation therapy device according to claim 8, further including:

at least one radiation detector being disposed in one of said cavities, and

a plug of substantially tissue-equivalent material being disposed in all of said cavities not containing one of said radiation detectors.

10. A method of using a phantom for radiation dose verification in a field of treatment of an intensity modulated radiation therapy device, comprising the steps of:

providing a phantom with a two-dimensional array of cavities, each said cavity being dimensioned and configured to receive a radiation detector;

positioning said phantom in said field of treatment;

generating at least one treatment plan which includes an image of said field of treatment with a plurality of isodose lines for the said radiation dose;

superimposing an image of said array of cavities over said treatment plan; and

selecting one of said cavities for placement of said radiation detector.

11. The method according to claim 10, wherein said step of selecting one of said cavities is based upon the disposition and concentration of said isodose lines relative to a cavity image of said selected cavity, said cavity image being part of said image of said array in said treatment plan.

12. The method according to claim 11, wherein said step of selecting one of said cavities includes selecting one of said cavity images of said treatment plan that is in a low gradient area of said isodose lines.

13. The method according to claim 10, further including the step of:

scanning said phantom to generate said image of said array of cavities, said image of said array comprising a CT scan of said phantom.

14. The method according to claim 11, wherein said step of generating said treatment plan further includes the steps of generating a CT-scan of the patient and superimposing said isodose lines over said CT-scan of said patient.

15. The method according to claim 14, further wherein said step of generating at least one treatment plan includes generating an original treatment plan and a hybrid treatment plan and said step of selecting one of said cavities for placement of said radiation detector being based upon said hybrid treatment plan.

16. The method according to claim 15, further including the steps of:

locating a first point of interest in said original treatment plan;

moving the center of said phantom to said first point of interest;

generating said hybrid treatment plan based upon a new point of interest; and

superimposing said CT scan of said array over said hybrid treatment plan.