Setup Of SIPM Based PET Detector Using LSO Background Radiation

Patent metadata

Field	Value
Publication number	US-2016299240-A1
Application number	US-201615075334-A
Country	US
Kind code	A1
Filing date	Mar 21, 2016
Priority date	Apr 7, 2015
Publication date	Oct 13, 2016
Grant date	—

Abstract

Systems and methods for configuring a radiation detector are provided. A first event is detected at a first scintillator crystal of a first detector unit. A second coincident event is detected at a second scintillator crystal of a second detector unit adjacent to the first detector unit. Operating parameters are calculated for the first detector unit based on the coincident events.

First claim

1 . A method for configuring a radiation detector including a plurality of detector units, the method comprising:
detecting a first radiation event at a first scintillator crystal of a first detector unit of the radiation detector, the first radiation event being assigned a first time mark; wherein the first radiation event is caused by a decay of a material in the first detector unit; detecting a second radiation event at a second scintillator crystal of a second detector unit of the radiation detector, the second radiation event related to and coincident to the first radiation event and being assigned a second time mark, wherein the first and second detector units are adjacent within the radiation detector; and calculating operating parameters for the first detector unit based on the coincident events.

2 . The method of claim 1 , wherein the first radiation event and second radiation event are caused by decay of Lu-176 in the first scintillator crystal.

3 . The method of claim 1 , wherein the first radiation event is related to a beta particle of the decay of the material and the second radiation event is related to a gamma particle of the decay of the material.

4 . The method of claim 1 , wherein detecting the first and second radiation events comprises detecting energy deposition information and position information for the first and second radiation events.

5 . The method of claim 4 , further comprising:
determining a time-walk correction calibration factor for the first and second scintillator crystals based on based on the energy deposition information, position information and time marks of one or more coincident events.

6 . The method of claim 4 , further comprising:
determining a time-walk correction calibration factor for the first and second detector units based on the energy deposition information, position information and time marks of one or more coincident events.

7 . The method of claim 4 , further comprising:
determining an energy calibration factor for the first and second detector units based on the energy deposition information, position information and time marks of one or more coincident events.

8 . The method of claim 4 , further comprising:
determining a photo-sensor bias voltage for the first and second detector units based on the energy deposition information, position information and time marks of one or more coincident events.

9 . The method of claim 4 , further comprising:
determining a discriminator trigger threshold for the first and second detector units based on the energy deposition information, position information and time marks of one or more coincident events.

10 . The method of claim 1 , further comprising:
acquiring a plurality of coincident events relating to the first scintillator crystal; and calculate a time offset for the first scintillator crystal based on the plurality of coincident events.

11 . A composite detector comprising:
a plurality of detector units, wherein each detector unit includes an array of scintillation elements and an array of photo-sensors; wherein a first detector unit of the plurality of detector units is configured to detect a first radiation event including detection of a first energy level and first position information; wherein a second detector unit of the plurality of detector units, adjacent to the first detector unit in the composite detector, is configured to detect a second radiation event related to the first radiation event, the second radiation event including detection of a second energy level and second position information; and a processing unit configured to: identify a coincidence of the first and second radiation events; and calculate operating parameters for the first detector unit and second detector unit based on the coincidence event.

12 . The composite detector of claim 11 , wherein the processing unit is further configured to:
calculate a relative time delay for each scintillation element in the first detector unit relative to an average time delay for the first detector unit.

13 . The composite detector of claim 11 , wherein the second energy level is different than the first energy level.

14 . The composite detector of claim 13 , wherein the first energy level and the second energy level are related to the decay of Lu-176 in a scintillator element in the first detector unit.

15 . The composite detector of claim 11 , wherein the processing unit is further configured to calculate operating parameters for the composite detector.

16 . A method comprising:
selecting initial operating parameters for a plurality of detector units in a positron emission tomography detector, wherein the plurality of detector units each include a plurality of scintillator crystals; acquiring self-activity data from the plurality of detector units; identifying one or more coincident events in adjacent detector units from the self-activity data; and calculating a timing offset for one or more of the plurality of scintillator crystals based on the coincident events.

17 . The method of claim 16 , further comprising:
selecting new operating parameters based on the one or more coincident events for each of the plurality of detector units, wherein the new operating parameters generate less jitter in the plurality of detector units than the initial operating parameters.

18 . The method of claim 16 , further comprising:
calculating average time differences between the plurality of detector units.

19 . The method of claim 16 , further comprising:
calculating a photo sensor bias voltage and a discriminator trigger threshold for each of the plurality of detector units.

20 . The method of claim 16 , wherein the self-activity data is generated from intrinsic radiation of the composite detector.

Assignees

• Siemens Medical Solutions Usa Inc

Inventors

• Cho Sanghee
• Mintzer Robert
• Breuer Johannes

Classifications

• G01T7/005

  calibration techniques (stabilization of spectrometer G01T1/40) · CPC title

• G01T1/2985 Primary

  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