Method and Apparatus for Automatic Calibration Check of PET Scanner Using Intrinsic Background Radiation of Scintillator Crystals

摘要

Gain values of PMTs of a PET scanner's detectors are balanced based on detected radiation from a radioactive calibration source placed in an FOV of the scanner. A time alignment is performed for scintillator crystals of the detectors based on TOF computations based on gamma photons associated with the radioactive calibration source. Baseline data is acquired using intrinsic background radiation of the scintillator crystals, without any object in the FOV. A first set of data, based on the baseline data, is stored in a memory of the scanner. After the acquisition of the baseline data, test data is acquired using intrinsic background radiation of the scintillator crystals, without any object in the FOV. A calibration status of the scanner or of an environment surrounding the scanner is automatically checked based on a comparison between the stored first set of data and a second set of data.

主权项

1. A method for operating a positron emission tomography (PET) scanner, the method comprising:
balancing gain values of a plurality of photomultiplier tubes of one or more detectors of the PET scanner based on detected radiation from a radioactive calibration source placed in a field of view of the PET scanner; performing a time alignment for a plurality of scintillator crystals of the detectors based on time-of-flight (TOF) computations based on gamma photons associated with the radioactive calibration source; acquiring baseline data using intrinsic background radiation of the plurality of scintillator crystals, without any object in the field of view; storing a first set of data, based on the baseline data, in a memory of the PET scanner; after the acquisition of the baseline data, acquiring test data using intrinsic background radiation of the plurality of scintillator crystals, without any object in the field of view; and automatically checking a calibration status of the PET scanner or of an environment surrounding the PET scanner based on a comparison between the stored first set of data and a second set of data, wherein the second set of data is based on the test data.