Instrumentation

Question 1

How does the spread of septa affect spatial res?

Answer 1

wider spread = lower res

Question 2

How does positron-sensitivity on PMT detector affect spatial res?

Answer 2

higher spatial res

Question 3

What are the advantages/disadvantages of the different collimator designs?

Answer 3

parallel: high sensitivity (450), most efficient

converging: high sens (300)
–> magnification (ex. heart)

diverging: mid sens (150)
–> whole body

pinhole: lowest sens (75), least efficient
–> large magnification (ex. animals)

Question 4

Scintillator materials and properties (density, light output, decay time) [PET]

Answer 4

LSO: 7.3 g/cc | 75% | 40 ns
BGO: 7.1 g/cc| 15% | 300 ns
GSO: 6.8 g/cc | 25% | 60 ns
Nal: 3.7 g/cc | 100% | 230 ns