Gamma-ray Compton TOF camera system

Patent metadata

Field	Value
Publication number	US-10281594-B2
Application number	US-201815970174-A
Country	US
Kind code	B2
Filing date	May 3, 2018
Priority date	Nov 4, 2015
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

A gamma ray Compton TOF camera system includes multiple detector modules, each comprising a gamma radiation sensitive material and arranged in layers formed by one or more detector modules. The layers are placed such that they interfere an incoming gamma ray in order to completely or partially absorb it after one or more Compton interactions and are spatially separated in order to allow for the determination of the temporal order of each gamma ray interaction inside the camera system. The camera system also includes read out electronics and a Data Acquisition System where signals from the detector modules will be readout, digitized and sent to a processing unit, which is capable to obtain the 3D position, energy and temporal sequential order of the individual interactions produced by a single incident gamma ray.

First claim

The invention claimed is:

1. A gamma ray Compton TOF camera system comprising
a plurality of detector modules, each detector module comprising a gamma radiation sensitive material,
said detector modules are arranged in layers formed by individual detector modules, or by sets of detector modules, said layers are placed in such a way that they interfere an incoming gamma ray, in order to completely or partially absorb it after one or more Compton interactions, and are spatially separated in order to allow for the determination of the temporal order of each gamma ray interaction inside the camera system,

read out electronics and Data Acquisition System where signals coming from the detector modules will be readout, digitized and sent to a processing unit for further analysis, and that is capable to obtain the 3D position, the energy and the temporal sequential order of the individual interactions—Compton and photoelectric-produced by a single incident gamma ray, allowing the determination of the full timing sequence of all gamma ray interactions inside a gamma ray detector volume.

2. The system according to claim 1 , wherein at least one detector module comprises scintillation crystal as gamma radiation sensitive material, optically coupled to arrays of photosensors.

3. The system according to claim 2 , wherein the photosensors are coupled to the scintillation crystal through at least one of a plurality of thinner side surfaces of each scintillation crystal.

4. The system according to claim 2 , wherein the scintillation crystal is a monolithic scintillation crystal.

5. The system according to claim 4 , wherein the monolithic scintillation crystal is selected from organic crystal scintillator, inorganic crystal scintillator, liquid scintillator, gas scintillator or combination of them for the different detector modules.

6. The system according to claim 4 , wherein the monolithic scintillation crystal is selected from LaBr 3 (Ce) or liquid Xe or combination of them for the different detector modules.

7. The system according to claim 2 , wherein the scintillation crystal is a pixelated scintillation crystal.

8. The system according to claim 2 , wherein the scintillation crystal is a combination of pixelated scintillation crystal for at least one detector module and at least one monolithic scintillation crystal for at least another one of the detector modules.

9. The system according to claim 2 , wherein the photosensors are arrays of silicon photomultipliers (SiPms), single photon avalanche diodes (SPADs), digital SiPms, avalanche photodiodes, position sensitive photomultiphers, photomultipliers, phototransistors, photodiodes, photo-ICs or combinations of them, for the different detector modules.

10. The system according to claim 2 , wherein at least one of the detector modules comprises Wave Length Shifter (WLS) fibers coupled to one or several of its scintillator surfaces to drive the light from the scintillator crystal towards the photosensors.

11. The system according to claim 2 , wherein at least one of the detector modules has at least one larger scintillator surface optically coupled to a reflector surface.

12. The system according to claim 11 , wherein at least one of the detector modules has a faceplate optically coupled between the reflector surface and the at least one larger scintillator surface.

13. The system according to claim 11 , wherein the reflector surface in at least one of the detector modules is selected between a retroreflector and a light absorbing surface.

14. The system according to claim 2 , wherein the detector modules include at least two larger scintillator surfaces and wherein at least one of the detector modules has one of its larger scintillator surfaces covered with WLS fibers coupled to photosensors on one or both WLS fiber ends, while the opposite larger scintillator surface is coupled to a reflector surface.

15. The system according to claim 2 , wherein the detector modules include at least two larger scintillator surfaces and wherein at least one of the detector modules has one of its larger scintillator surface covered with WLS fibers coupled to photosensors on one or both WLS fiber ends, while the other one of the larger scintillator surface is covered by a faceplate optically coupled between a reflector and the scintillator face.

16. The system according to claim 1 , wherein at least one of the detector modules are made of solid state detector.

17. The system according to claim 1 , wherein at least one of the detector modules comprise Cherenkov radiators as gamma radiation sensitive material.

18. A device for imaging gamma ray sources comprising a gamma ray Compton TOF camera system comprising
a plurality of detector modules, each detector module comprising a gamma radiation sensitive material,
said detector modules are arranged in layers formed by individual detector modules, or by sets of detector modules, said layers are placed in such a way that they interfere an incoming gamma ray, in order to completely or partially absorb it after one or more Compton interactions, and are spatially separated in order to allow for the determination of the temporal order of each gamma ray interaction inside the camera system,

read out electronics and Data Acquisition System where signals coming from the detector modules will be readout, digitized and sent to a processing unit for further analysis, and that is capable to obtain the 3D position, the energy and the temporal sequential order of the individual interactions—Compton and photoelectric-produced by a single incident gamma ray, allowing the determination of the full timing sequence of all gamma ray interactions inside a gamma ray detector volume.

19. The device according to claim 18 , that is a Positron Emission Tomography device.

20. The device according to claim 19 , that is a Positron Emission Tomography device wherein the detector modules form concentric cylinders.

21. The device according to claim 18 , that is a Single Photon Emission Computed Tomography device.

22. The device according to claim 18 , that is a Positron Emission Tomography wherein the detector modules form concentric cylinders surrounding an object under study.

23. A method for obtaining images by nuclear techniques comprising detecting and processing radiation with a gamma ray Compton TOF camera system comprising
a plurality of detector modules, each detector module comprising a gamma radiation sensitive material,
said detector modules are arranged in layers formed by individual detector modules, or by sets of detector modules, said layers are placed in such a way that they interfere an incoming gamma ray, in order to completely or partially absorb it after one or more Compton interactions, and are spatially separated in order to allow for the determination of the temporal order of each gamma ray interaction inside the camera system,

read out electronics and Data Acquisition System where signals coming from the detector modules will be readout, digitized and sent to a processing unit for further analysis, and that is capable to obtain the 3D position, the energy and the temporal sequential order of the individual interactions—Compton and photoelectric-produced by a single incident gamma ray, allowing the determination of the full timing sequence of all gamma ray interactions inside a gamma ray detector volume.

Assignees

• Consejo Superior Investigacion
• Univ Valencia Politecnica

Inventors

• Benlloch Baviera José María
• Sánchez Martínez Filomeno
• González Martínez Antonio Javier

Classifications

• G01T1/17

  Circuit arrangements not adapted to a particular type of detector {(pulse-selection circuits H03K, G01R)} · CPC title

• G01T1/2006

  using a combination of a scintillator and photodetector which measures the means radiation intensity · CPC title

• G01T1/2002

  Optical details, e.g. reflecting or diffusing layers · CPC title

• G01T1/247

  Detector read-out circuitry (for processing gain or off-set correction H04N) · CPC title

• G01T1/2985

  In depth localisation, e.g. using positron emitters; Tomographic imaging (longitudinal and transverse section imaging; apparatus for radiation diagnosis sequentially in different planes, steroscopic radiation diagnosis); (using external radiation sources A61B6/02) · CPC title