Large-volume scintillator detector for rapid real-time 3-d dose imaging of advanced radiation therapy modalities

Patent metadata

Field	Value
Publication number	US-2016103227-A1
Application number	US-201414893872-A
Country	US
Kind code	A1
Filing date	May 30, 2014
Priority date	May 31, 2013
Publication date	Apr 14, 2016
Grant date	—

Abstract

An apparatus and method for measuring three-dimensional radiation dose distributions with high spatial and temporal resolution using a large-volume scintillator. The scintillator converts the radiation dose distribution into a visible light distribution. The visible light is transported to one or more photo-detectors, which measure the light intensity. The light signals are processed to correct for optical artifacts, and the three-dimensional light distribution is reconstructed. The reconstructed light distribution is post-processed to convert light amplitudes to measured radiation doses. The high temporal resolution of the detector makes it possible to observe the evolution of a dynamic dose distribution as it changes over time. Integral dose distributions can be measured by summing the dose over time.

First claim

1 . A radiation dose detector device, comprising:
a scintillating element; a plurality of light detectors configured to detect light emitted from the scintillating element; and a computer, wherein the computer is configured to receive data from the plurality of light detectors and configured to generate a three-dimensional map of light emitted from the scintillating element.

2 . The radiation dose detector device of claim 1 wherein the plurality of light detectors are configured to simultaneously detect light emitted from the scintillating element.

3 . The radiation dose detector device of claim 1 wherein at least one of the plurality of light detectors are selected from the group consisting of: charge-coupled device (CCD) cameras, complementary metal-oxide sensor (CMOS) cameras, light field cameras, photodiode arrays and photomultiplier tube arrays.

4 . The radiation dose detector device of claim 1 wherein the plurality of light detectors are coupled to a housing.

5 . The radiation dose detector device of claim 1 further comprising a collimator between the scintillating element and at least one of the plurality of light detectors.

6 . The radiation dose detector device of claim 1 further comprising one or more optical fibers between the scintillating element and at least one of the plurality of light detectors.

7 . The radiation dose detector device of claim 1 wherein the computer comprises a computer readable medium comprising software configured to execute a pre-processing algorithm, a tomographic reconstruction algorithm and a post-processing algorithm.

8 . The radiation dose detector device of claim 7 wherein the pre-processing algorithm is configured to correct for both optical and dosimetric artifacts.

9 . The radiation dose detector device of claim 7 wherein the tomographic reconstruction algorithm converts data received from the plurality of light detectors into a three-dimensional dose distribution.

10 . The radiation dose detector device of claim 9 wherein the tomographic reconstruction algorithm comprises a filtered backprojection algorithm.

11 . The radiation dose detector device of claim 9 wherein the tomographic reconstruction algorithm comprises an iterative algorithm.

12 . The radiation dose detector device of claim 7 wherein the post-processing algorithm is configured to convert grayscale levels of three-dimensional light distribution into actual dose values by comparison with a reference measurement.

13 . A three-dimensional radiation dose detector device, comprising:
a large continuous volumetric scintillating element; and means for measuring the light emission from said scintillating element from multiple positions or directions simultaneously and with high temporal resolution.

14 . The radiation dose detector device of claim 13 wherein the continuous volumetric scintillating element has a volume of about 500 to 15,000 cubic centimeters.

15 . The radiation dose detector device of claim 13 wherein the temporal resolution is up to 100 samples per second.

16 . The radiation dose detector device of claim 13 , wherein said scintillating element is an organic or inorganic material in solid, liquid, or gelatinous state.

17 . The radiation dose detector device of claim 13 , wherein said means for measuring light emission comprises one or more charge-coupled devices, complementary metal-oxide-semiconductor devices, light field cameras, photomultiplier tubes, photodiodes, avalanche photodiodes, or other devices capable of light detection.

18 . The radiation dose detector device of claim 13 , wherein said means of measuring light emission comprises one or more light-field imagers or plenoptic cameras.

19 . The radiation dose detector of claim 13 , wherein said means for measuring light emission includes detectors equally spaced at an angle θ, with the sum of all angles equal to 360 degrees.

20 . The radiation dose detector device of claim 13 , wherein said means for measuring light emission includes detectors unequally-spaced at angles θi, where the sum of all θi equals 360 degrees or less.

21 . The radiation dose detector device of claim 13 , wherein said means for measuring light emission includes detectors in non-planar distributions, including spherical, cubic, and other three-dimensional detector distributions.

22 . The radiation dose detector device of claim 13 , wherein said volumetric scintillating element is formed in the shape of a cube, cylinder, sphere, ellipsoid, prism, or other geometric shape.

23 . The radiation dose detector device of claim 13 , wherein said volumetric scintillating element is formed in a shape similar to one or more parts of a human body.

24 . The radiation dose detector device of claim 13 , wherein said volumetric scintillating element is encased in a body that is transparent to the scintillation light.

25 . The radiation dose detector device of claim 24 , wherein said transparent encasing body is formed in a cube, cylinder, sphere, ellipsoid, prism, or other geometric shape.

26 . The radiation dose detector device of claim 24 , wherein said transparent encasing body is formed in a shape similar to one or more parts of a human body.

27 . The radiation dose detector device of claim 13 , wherein the surface of said volumetric scintillating element is treated to prevent light reflection at the interface between said volumetric scintillating element and any adjacent components or the surrounding medium.

28 . The radiation dose detector device of claim 13 , further including a light-guiding apparatus which directs light from said volumetric scintillating element to said means for measuring light emission.

29 . The radiation dose detector device of claim 28 , wherein said light-guiding apparatus includes fiber optics with low numerical aperture.

30 . The radiation dose detector device of claim 28 , wherein said light-guiding apparatus includes lenses and/or mirrors.

31 . The radiation dose detector device of claim 28 , wherein said light-guiding apparatus includes gaps at one or more angles whereby radiation from an external source may enter said volumetric scintillating detector without passing through said light-guiding apparatus.

32 . The radiation dose detector device of claim 13 , further including a collimator grid between said volumetric scintillating element and said means for measuring light emission.

33 . The radiation dose detector device of claim 32 , wherein said collimator grid includes gaps at one or more angles whereby radiation from an external source may enter said volumetric scintillating detector without passing through said collimator grid.

34 . The radiation dose detector device of claim 13 , wherein the measurement of light emission is performed with high temporal resolution.

35 . The radiation dose detector device of claim 34 wherein the temporal resolution is up to 100 samples per second.

36 . The radiation dose detector device of claim 13 , wherein said means for measuring the light emission is activated and/or deactivated by a signal from a radiation generating device or a radiation source control or monitoring mechanism.

37 . The radiation dose de

Assignees

• Univ Laval
• Univ Texas
• UNIVERSITé LAVAL

Inventors

• Beddar A Sam
• Archambault Louis
• Robertson Daniel

Classifications

• G01T1/2042

  Composition for liquid scintillation systems · CPC title

• A61N5/1071

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

• G01T1/10 Primary

  Luminescent dosimeters · CPC title

• G01T1/29 Primary

  Measurement performed on radiation beams, e.g. position or section of the beam; Measurement of spatial distribution of radiation · CPC title