Systems and methods for calibrating a nuclear medicine imaging system

A system, comprising:

• a gantry defining a bore;
• a calibration source comprising a radioactive line source and a fluorescence source, the calibration source positioned within the bore;
• a plurality of detectors coupled to the gantry and configured to detect radiation from the calibration source;
• and
• a processor communicatively coupled to the plurality of detectors and configured with instructions in non-transitory memory that, when executed, cause the processor to:
• detect, with the plurality of detectors, photons emitted by the calibration source while pivoting one or more detectors of the plurality of detectors;
• apply a geometrical correction to an energy spectrum of the detected photons by adjusting photon counts and energy measurements recorded by pixels of the one or more detectors according to the pivoting of the one or more detectors, wherein adjusting the photon counts and the energy measurements for a pixel includes increasing or decreasing the photon counts and the energy measurements according to a position of the pixel;
• and
• adjust a gain and an offset of at least one detector of the plurality of detectors based on the geometrically-corrected energy spectrum of the detected photons.

A system, comprising:

• a detector of a nuclear medicine (NM) imaging system with a length along an axial direction of the NM imaging system;
• and
• a calibration source positioned within the NM imaging system for calibrating the detector, the calibration source comprising:
• a radioactive line source shaped as a cylinder with a length equal to or greater than the length of the detector of the NM imaging system, the radioactive line source comprising a radioisotope with an energy spectrum including a first energy peak;
• and
• a fluorescence source, wherein an energy spectrum of the fluorescence source includes a second energy peak, the second energy peak distinguishable from the first energy peak by the detector.