Scintillator material

Patent metadata

Field	Value
Publication number	US-9598638-B2
Application number	US-201314440681-A
Country	US
Kind code	B2
Filing date	Oct 31, 2013
Priority date	Nov 14, 2012
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

A gamma photon detector for detecting 511 keV PET radiation includes a scintillator host material doped with cerium. The cerium is present in a concentration of 0.1 to 1.0 mol %. Lower concentrations increase light output but also decay times which can lead to pile up issues. The higher light output enables the read out area to be decreased which reduces the pile up issues. Embodiments with a cerium concentration as low as 0.15 to 0.2 mol % and a read out area as low as 0.1 cm 2 are contemplated.

First claim

The invention claimed is:

1. A gamma photon detector for detecting individual 511 keV gamma photons in a PET imaging system, the gamm photon detector comprising:
an optical detector; and
a garnet scintillator material with a substantially ceramic or polycrystalline structure and a decay time of less than 300 ns having the composition represented by (Gd 3-x-y Lu x Ce y )(Al 5-z Ga z-a Lu a )O 12 , wherein:
x is in the range 0 to 0.6,
y is in the range 0.003 to 0.03,
z is in the range 1.5 to 3.5,
a is in the range 0 to 0.3,
z-a is in a range of 2.41 to 2.51,
cerium (Ce) has a concentration of 0.15 to 0.6 mol %,
the scintillator material has a density in excess of 7 g/cm 3 , and
a gamma photon read out area is less than 5 cm 2 .

2. The gamma photon detector according to claim 1 , wherein the garnet scintillator material has a composition represented by (Gd 2.7-y Lu 0.3 Ce y )(Al 2.5 Ga 2.47 Lu 0.03 )O 12 wherein y is in the range 0.003 to 0.03.

3. The gamma photon detector according to claim 2 , wherein the garnet scintillator material has a decay time of less than 300 ns.

4. The gamma photon detector according to claim 1 , wherein the scintillator composition is controlled such that the scintillator material has a density in excess of 8 g/cm 3 .

5. A PET imaging system having an imaging region and comprising:
a plurality of gamma photon detectors according to claim 1 disposed radially about the imaging region and configured to receive gamma photons from said imaging region, wherein each gamma photon includes a solid state semiconductor optical detector.

6. A method of generating a PET image indicative of the distribution of a radiotracer within an imaging region, the method comprising: administering a radiotracer to a subject; waiting for a predefined uptake period after administering the radiotracer; and imaging at least a portion of the subject with the PET imaging system according to claim 5 .

7. The PET imaging system according to claim 5 , wherein:
the cerium concentration is 0.15 to 0.4 mol %, and
the gamma photon read out area is less than 0.5 cm 2 .

8. The PET imaging system according to claim 7 , wherein:
a=0.03.

9. The PET imaging system according to claim 5 , wherein:
the cerium concentration is 0.15 to 0.2 mol %, and
the read out area is less than 0.2 cm 2 .

10. The gamma photon detector according to claim 1 , wherein the cerium concentration is 0.15 to 0.4 mol %.

11. The gamma photon detector according to claim 10 , wherein the gamma photon read out area is less than 0.5 cm 2 .

12. The gamma photon detector according to claim 10 , wherein the gamma photon read out area is less than 0.2 cm 2 .

13. The gamma photon detector according to claim 1 , wherein the cerium concentration is 0.15 to 0.2 mol %.

14. The gamma photon detector according to claim 13 , wherein the gamma photon read out area is less than 0.2 cm 2 .

15. The gamma photon detector according to claim 13 , wherein the gamma photon read out area is less than 0.1 cm 2 .

16. The gamma photon detector according to claim 1 , wherein the gamma photon read out area is less than 2 cm 2 .

17. The gamma photon detector according to claim 1 , wherein the gamma photon read out area is less than 1 cm 2 .

18. The gamma photon detector according to claim 1 , wherein the gamma photon read out area is less than 0.5 cm 2 .

19. The gamma photon detector according to claim 1 , wherein the gamma photon read out area is less than 0.2 cm 2 .

20. The gamma photon detector according to claim 1 , wherein the gamma photon read out area is less than 0.1 cm 2 .

Assignees

• Koninklijke Philips Nv

Inventors

• Ronda Cornelis Reinder
• Boerekamp Jacobus Gerardus
• Spoor Sandra Johanna Maria Paula
• Van Dongen Anne-Marie Andree
• Wieczorek Herfried Karl
• Keur Wilhelmus Cornelis

Classifications

• 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

• C04B2235/3215

  Barium oxides or oxide-forming salts thereof · CPC title

• C04B35/44

  based on aluminates · CPC title

• G01T1/2023

  Selection of materials · CPC title

• C04B35/547

  based on sulfides or selenides {or tellurides} · CPC title