PET and PET/CT Instrumentation

Subgroup IV: Instrument Operations and Quality Control

PET QC procedures

daily blank scan, tomographic uniformity, normalization scan, well counter / cross calibration, resolution

PET blank scan procedure

• sinograms produced for every possible detector pair in each detector ring

• printout showing acquisition parameters

PET blank scan source

Ge-68 source

What acquisition parameters are included in the PET blank scan printout?

coincidence count rate, singles count rate, dead time, coincidence timing, energy response

What is the problem with this blank scan?

bad detector block

What is the problem with this PET blank scan printout?

bad detector block

tomographic uniformity source

Ge-68 cylinder

How often is PET tomographic uniformity performed?

weekly

How often is PET normalization scan performed?

monthly or quarterly

PET normalization scan purpose

evaluate differences in sensitivity of the crystals in each pair of detectors

When should PET normalization factors be updated?

only after major service or deteriorating image quality

PET well counter / cross calibration procedure

• measure a known amount of activity in the dose calibrator

• correlate cps/voxel and uCi/mL

PET well counter / cross calibration source

cylindrical phantom with known amount of activity