Physics

Question 1

Spatial resolution determinants in plain film radiography

Answer 1

1. Detector
2. Motion artifact
3. Effective focal spot size

Question 2

Causes of noise in plain film radiography

Answer 2

1. Shot noise (too few photons)

2. Compton scatter

Question 3

Resolution in line pairs per mm

Answer 3

1 / 2 x pitch

Question 4

Total MR acquisition time

Answer 4

TR x # phase encoding steps x # of excitations (NEX)

Question 5

Detector pitch for square detector

Answer 5

FOV length / Matrix length

Question 6

Spatial resolution (line pairs per mm)

Answer 6

1 / 2 x detector pitch

Question 7

ACR mammography phantom

Answer 7

Equivalent to a 4.2 cm thick breast with 50% glandularity

Question 8

Successful visualization of ACR mammography phantom (contains 6 fibers, 5 speck groups, and 5 masses)

Answer 8

Old: 4, 3, 3
New: 2,3,2 (as of 2018, can be used for digital and tomo)