System and method for endo-rectal retraction and organ immobilization for radiotherapy of the pelvis

Patent metadata

Field	Value
Publication number	US-10874879-B2
Application number	US-201515517776-A
Country	US
Kind code	B2
Filing date	Oct 8, 2015
Priority date	Oct 8, 2014
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

A system for monitoring doses from an ionizing radiation source to a treatment region of a patient and immobilizing a body cavity relative to the treatment region, is provided. The system includes a probe body for insertion into the body cavity. The probe body separates the body cavity from the treatment region to reduce exposure to doses from the ionizing radiation source. Radiation detectors are disposed along the probe body to measure at least one dose. A slot disposed adjacent the radiation detectors receives a dosimetry film that, upon exposure to the one or more doses from the ionizing radiation source, indicates a quantification of the doses. A coupling is in fluid communication with a removable sheath having coupled thereto a vacuum or a pump to remove fluid or gas from the body cavity and ensure inner wall of the body cavity is in contact with the sheath.

First claim

The invention claimed is:

1. A system for monitoring doses from an ionizing radiation source to a treatment region of a patient, the system comprising:
a probe body for insertion into a body cavity near the treatment region of the patient;
a plurality of radiation detectors disposed along a proximal end of the probe body to measure at least one dose from the ionizing radiation source; and
a slot disposed adjacent the plurality of radiation detectors, the slot configured to receive a dosimetry film that, upon exposure to the at least one dose from the ionizing radiation source, indicates a quantification of the at least one dose from the ionizing radiation source;
wherein the probe body is dimensioned to separate a portion of the body cavity from the treatment region to reduce exposure of membranous tissue surrounding the body cavity to the at least one dose from the ionizing radiation source.

2. The system as recited in claim 1 wherein at least one of the probe body, the plurality of radiation detectors, and the dosimetry film are compatible with at least one of magnetic resonance imaging systems and computed tomography imaging system.

3. The system as recited in claim 1 wherein the body cavity is a rectum, and the probe body is dimensioned to immobilize the rectum so that the rectum does not move into a high dose treatment region.

4. The system as recited in claim 1 wherein the plurality of radiation detectors are optically stimulated luminescence (OSL) detectors.

5. The system as recited in claim 1 wherein the dosimetry film is at least one of a radiochromic film and a radiographic film.

6. The system as recited in claim 5 wherein the radiochromic film is a GafChromic film.

7. The system as recited in claim 6 wherein the GafChromic film is a GafChromic EBT3 film.

8. The system as recited in claim 1 further comprising:
a vertical stage including a docking socket for receiving a docking plunger coupled to the probe body; and
wherein the vertical stage includes at least one of a height adjustment, a lateral adjustment, a rotational adjustment and an anterior-posterior adjustment for the probe body.

9. The system as recited in claim 8 wherein the probe body and the vertical stage are configured for coupling to a treatment couch to limit incorrect set up of the probe body.

10. The system as recited in claim 1 further comprising:
a vertical stage coupled to the probe body, the vertical stage including a plurality of adjustments for the probe body; and
wherein the plurality of adjustments for the probe body correspond to a plurality of measurement guides to limit incorrect set up of the probe body.

11. The system as recited in claim 10 wherein the plurality of adjustments are adjusted using at least one of a thumb screw and a manual technique.

12. The system as recited in claim 1 further comprising:
a removable sheath including a plurality of perforations fluidly coupled to a passageway to passively remove gas from the body cavity.

13. The system as recited in claim 12 wherein the removable sheath includes a coupling in fluid communication with the passageway and configured to connect to a pump to actively remove gas from the body cavity.

14. The system as recited in claim 12 wherein the removable sheath provides active adherence of an inner wall of the body cavity to the probe body to increase immobilization of at least one of the body cavity and the treatment region.

15. The system as recited in claim 12 wherein the removable sheath includes a measurement guide disposed on an outer surface to provide reproducible set up of the probe body relative to the body cavity.

16. The system as recited in claim 1 wherein the probe body is constructed from a material that is at least one of capable of withstanding steam sterilization for reusability of the probe body and compatible with at least one of magnetic resonance imaging and x-ray imaging.

17. A method for providing end-to-end quality assurance, the steps of the method comprising:
providing a dosimetry film to the system recited in claim 1 ;
measuring a dose distribution by exposing the dosimetry film to radiation;
providing a planned dose distribution;
resampling the planned dose distribution to a plane of the dosimetry film; and
assessing quality assurance by comparing the resampled planned dose distribution with the measured dose distribution.

18. A device for immobilizing a body cavity relative to an anatomic region-of-interest, the device comprising:
a probe for insertion into the body cavity;
a removable sheath including a plurality of perforations formed in a surface thereof, the removable sheath configured to receive the probe; and
a coupling in fluid communication with the removable sheath, the coupling configured to be coupled to a pump to actively remove at least one of fluid and gas from the body cavity.

19. The device as recited in claim 18 wherein the body cavity is a rectum, and the probe is dimensioned to immobilize the rectum so that the rectum does not move into a high dose treatment region adjacent the anatomic region-of-interest.

20. The device as recited in claim 18 wherein probe includes a plurality of radiation detectors disposed along a proximal end of the probe to measure at least one dose from an ionizing radiation source.

21. The device as recited in claim 20 wherein the plurality of radiation detectors are optically stimulated luminescence (OSL) detectors.

22. The device as recited in claim 20 wherein the probe includes a slot disposed adjacent the plurality of radiation detectors, the slot configured to receive a dosimetry film that, upon exposure to the at least one dose from the ionizing radiation source, indicates a quantification of the at least one dose from the ionizing radiation source.

23. The device as recited in claim 22 wherein the dosimetry film is at least one of a radiochromic film and a radiographic film.

24. The device as recited in claim 23 wherein the radiochromic film is a GafChromic EBT3 film.

Assignees

• Sunnybrook Res Inst

Inventors

• Ravi Ananth
• Easton Harry

Classifications

• A61N2005/1094

  Shielding, protecting against radiation · CPC title

• A61N2005/1097

  Means for immobilizing the patient · CPC title

• G01T1/10

  Luminescent dosimeters · CPC title

• A61N5/1071 Primary

  for verifying the dose delivered by the treatment plan · CPC title

• A61N5/1075

  for testing, calibrating, or quality assurance of the radiation treatment apparatus · CPC title