NMTCB PET Questions With Correct Answers Graded A+

The exposure rate of an activity of 1 millicurie (mci) measured at 1 centimeter (cm) is called - The exposure rate constant (ERC) For positron emitters, the exposure rate constant (ERC) is about 6 R/h per milli- curie at 1 cm. The exposure rate of a 10 mci dose of F-18 is approximately six times greater than that of a 10 mci dose of Tc-99 m at a distance of approximately 8 inches. Quantitative bias that refers to the underestimation of counts density which differs from what they should be is called: Partial-volume effect PVE is caused by the finite spatial resolution of the imaging system which reveals how far the signal "spills out" around its actual location. The signal spreading falsely increases the object size and volume. Image sampling, where voxels in ROI include the signal from underlying tissues, also contributes to the phenomenon known as partial-volume effect. Truncation artifacts in PET/CT imaging are produced by Difference in size of FOV between PET and the CT Discrepancy between fields of view (FOVs) in a PET/CT scanner—70 cm causes a truncation artifact when imaging extends beyond the CT FOV-50 cm; as a result, no attenuation correction values for the truncated anatomy are being applied.