Combined imaging detector for x-ray and nuclear imaging

Patent metadata

Field	Value
Publication number	US-10942282-B2
Application number	US-201716329824-A
Country	US
Kind code	B2
Filing date	Sep 6, 2017
Priority date	Sep 13, 2016
Publication date	Mar 9, 2021
Grant date	Mar 9, 2021

Abstract

The invention relates to a combined imaging detector for detection of gamma and x-ray quanta comprising an x-ray detector ( 31 ) for generating x-ray detection signals in response to detected x-ray quanta and a gamma detector ( 32 ) for generating gamma detection signals in response to detected gamma quanta. The x-ray detector ( 31 ) and the gamma detector ( 32 ) are arranged in a stacked configuration along a radiation-receiving direction ( 33 ). The gamma detector ( 32 ) comprises a gamma collimator plate ( 320 ) comprising a plurality of pinholes ( 321 ), and a gamma conversion layer ( 322, 324 ) for converting detected gamma quanta into gamma detection signals.

First claim

The invention claimed is:

1. A gamma detector for generating gamma detection signals in response to detected gamma quanta, the gamma detector comprising:
a gamma collimator plate comprising a plurality of pinholes, wherein the pinholes of the gamma collimator plate have a first pitch in a first direction;
a gamma conversion layer adapted to convert detected gamma quanta into gamma detection signals, wherein the gamma collimator plate and the gamma conversion layer are in contact with each other, and are arranged in a stacked configuration along a radiation-receiving direction; and
an actuator configured to provide a relative displacement between the gamma collimator plate and the gamma conversion layer, wherein the displacement has a magnitude that is less than or equal to the first pitch.

2. A gamma imaging method for use with the gamma detector according to claim 1 , the gamma imaging method comprising:
generating gamma detection signals with the gamma detector with the gamma collimator plate and the gamma conversion layer in a first mutual arrangement;
causing the actuator to provide the displacement between the gamma collimator plate and the gamma conversion layer such that the gamma collimator plate and the gamma conversion layer are in a second mutual arrangement;
generating gamma detection signals with the gamma detector with the gamma collimator plate and the gamma conversion layer in the second mutual arrangement; and
reconstructing a gamma image based on the gamma detection signals generated with the gamma collimator plate and the gamma conversion layer in the first mutual arrangement and the second mutual arrangement.

3. A tangible, non-transitory computer readable medium that stores instructions which, when executed on a processor controlling the gamma detector, cause the processor to carry out the gamma imaging method according to claim 2 .

4. A gamma imaging system comprising the gamma detector according to claim 1 , and further comprising an actuator control system;
wherein the gamma imaging system has an imaging region and an imaging axis passing therethrough for receiving a patient along the imaging axis;
wherein the gamma detector is disposed along a radius with respect to the imaging axis;
wherein the displacement direction is perpendicular to the radius; and
wherein the actuator control system is configured to control the actuator to cause either i) a relative displacement between the gamma collimator plate and the gamma conversion layer, or ii) a displacement of the gamma detector such that the gamma detector generates gamma detection signals in each of two displacement positions for use in reconstructing a gamma image.

5. The gamma imaging system according to claim 4 , wherein the displacement direction is parallel to the imaging axis.

6. A combined imaging detector for detection of gamma and x-ray quanta, the combined imaging detector comprising the gamma detector according to claim 1 ; and an x-ray detector for generating x-ray detection signals in response to detected x-ray quanta, wherein the x-ray detector is arranged in a stacked configuration with respect to the gamma detector along the radiation-receiving direction.

7. The gamma detector as claimed in claim 1 ,
wherein a number of pinholes of said gamma collimator plate is equal to or smaller than a number of gamma detector elements of the gamma conversion layer, wherein one pinhole and one or more corresponding gamma detector elements are arranged in a stacked configuration along the radiation-receiving direction and the pinhole is centered with respect to the one or more corresponding gamma detector elements.

8. The gamma detector as claimed in claim 1 ,
wherein said gamma collimator plate is made from a lead or tungsten plate, in which the plurality of pinholes are formed.

9. The gamma detector as claimed in claim 1 ,
wherein said gamma collimator plate is made from an absorption plate, in which a plurality of pinhole inserts including said pinholes are integrated.

10. The gamma detector as claimed in claim 1 ,
wherein said pinholes are knife-edge or tapered pinholes.

11. The gamma detector as claimed in claim 1 ,
wherein the plurality of pinholes each have a projection area having a round, square, or hexagonal shape.

12. The gamma detector as claimed in claim 1 ,
wherein projection areas of neighboring pinholes overlap or wherein projection areas of neighboring pinholes are separated by septa.

13. The gamma detector as claimed in claim 1 ,
wherein said gamma conversion layer includes a direct gamma conversion layer or an indirect gamma conversion layer.

14. A combined imaging detector for detection of gamma quanta and x-ray quanta, the combined imaging detector comprising:
an x-ray detector adapted to generate x-ray detection signals in response to detected x-ray quanta, the x-ray detector comprising: an x-ray conversion layer adapted to convert detected x-ray quanta into x-ray detection signals; read-out electronics; and a foil substrate, the x-ray conversion layer and the read-out electronics being arranged on the foil substrate such that the read-out electronics are disposed laterally with respect to the x-ray conversion layer; and
a gamma detector adapted to generate gamma detection signals in response to detected gamma quanta, the gamma detector comprising: a gamma collimator plate comprising a plurality of pinholes, wherein material of the x-ray conversion layer adjacent to one or more of the plurality of pinholes is removed, or is thinner than in other areas not adjacent to the pinhole; and a gamma conversion layer adapted to convert detected gamma quanta into gamma detection signals, wherein the x-ray detector and the gamma detector are arranged in a stacked configuration along a radiation-receiving direction.

15. The combined imaging detector as claimed in claim 14 ,
wherein the gamma detector is controlled to generate gamma detection signals when no x-ray quanta are incident on the combined imaging detector.

16. The combined imaging detector as claimed in claim 14 ,
wherein said x-ray detector further comprises
an x-ray anti-scatter grid.

17. An imaging system comprising:
an x-ray source adapted to emit pulsed x-ray radiation comprising two split x-ray beams at different angles, and
a combined imaging detector adapted to detect gamma and x-ray quanta, the combined imaging detector comprising:
an x-ray detector adapted to generate x-ray detection signals in response to detected x-ray quanta; and
a gamma detector adapted to detect gamma detection signals in response to detected gamma quanta, the gamma detector comprising: a gamma collimator plate comprising a plurality of pinholes; and
a gamma conversion layer for converting detected gamma quanta into gamma detection signals, wherein the x-ray detector and the gamma detector are arranged in a stacked configuration along a radiation-receiving direction..

18. The imaging system as claimed in claim 17 , further comprising a control unit configured to control said combined imaging detector to detect gamma quanta during intervals between x-ray pulses.

19. The imaging system as claimed in claim 18 , wherein the control unit is further configured to either i) identify gamma detection signals generated by the gamma detector during x-ray pulses for exclusion from a reconstruction of a corresponding gamma image or ii) control the gamma detector to inhibit or suppress the generation of gamma detection signals during said x-ray pulses.

20. The imag

Assignees

• Koninklijke Philips Nv

Inventors

• Wieczorek Herfried Karl
• Jacobs Johannes Wilhelmus Maria
• Stegehuis Herman
• Radaelli Alessandro
• Kok Christiaan
• Alving Peter Lex

Classifications

• A61B6/037 Primary

  Emission tomography · CPC title

• G01T1/1611

  using both transmission and emission sources sequentially (SPECT imaging G01T1/1642; PET imaging G01T1/2985; detecting prohibited goods, e.g. weapons, explosives, hazardous substances, contraband or smuggled objects G01V5/20) · CPC title

• A61B6/4441

  the rigid structure being a C-arm or U-arm · CPC title

• A61B6/4417

  related to combined acquisition of different diagnostic modalities · CPC title

• A61B6/487

  involving fluoroscopy · CPC title