Positron Emission Tomography Chapter 8

Match the following phrases with the term

singles events

one 511keV photon from a single annihilation event strikes a detector and the other is absorbed by surrounding tissue

Match the following phrases with the term

random events

two 511keV photons arising from separate annihilation events striking opposing detectors simultaneously

Match the following phrases with the term

true coincidence events

two 511keV photons arising from a single annihilation event striking opposing detectors simultaneously

Which of the following characteristics are desirable for the crystalline materials used to detect 511keV photons

high atomic number

high light yield

True or False: coincidence circuitry can more readily differentiate singles events from true coincidence events than random events from true coincidence events

true

What is one factor that tends to reduce resolution in PET imaging

the positrons can travel a significant distance prior to annihilation

What is a second factor that tends to reduce resolution in PET imaging

511keV photon emissions are not always exactly 180 degrees apart following an annihilation reaction

What is a 3rd factor that tends to reduce resolution in PET imaging

proximity of the source to the edge of the ring of detectors

Which of the following are true about current time of flight annihilation detection technology on PET scanners

approximate localization of an annihilation event along a line of response can be used to improve image quality

True or False: standard uptake value (SUV) measurements based on body surface area may be more accurate than those based on weight alone in obese patients because adipose tissue does not concentrate FDG as much as the rest of the tissue in the body

True