Construction of XR unit and misc XR stuff

Question 1

Detail use of tungsten in xray tubes

Answer 1

Question 2

What is the approximate voltage / current of the filament circuit?

Answer 2

Question 3

Describe focal spots, including trade offs

Answer 3

Question 4

Describe the heel effect. What factors are important / can be modified to limit effect?

Answer 4

Question 5

Describe magnification radiography, including features that contribute to magnification, and how to calculate magnification factors

Answer 5

Question 6

Detail differences between stationary and rotating anodes

Answer 6

Question 7

What are standard anode angles in radiography?

Answer 7

Question 8

Factors managing heat production in the x ray tube

Answer 8

Question 9

Detail inherent and added beam filtration

Answer 9

Question 10

Briefly describe mechanisms for mA and kVp regulation

Answer 10

Question 11

Describe AC and DC current. What is the advantage of AC?

Answer 11

Question 12

Describe transformers. What is the law of transformers?

Answer 12

Question 13

Compare and contrast tube and filament circuits

Answer 13

Question 14

Define rectification

Answer 14

Question 15

Outline how semiconductors work. What contains a semiconductor in the xray unit? What materials are used?

Answer 15

Question 16

Describe three phase and capacitor generators

Answer 16

Question 17

Describe falling load principle

Answer 17

Question 18

Describe high frequency generators

Answer 18

Question 19

What is voltage ripple?

Answer 19

Question 20

Describe different types of exposure timer x 2

Answer 20

Question 21

How does voltage ripple vary between generator types?

Answer 21

Question 22

Approximate the different energies of superficial, diagnostic xrays; orthovoltage, megavoltage x rays; and gamma rays.

Answer 22

Question 23

What are power ratings? Know the appropriate formulae x 2

Answer 23

Question 24

Describe different collimator types

Answer 24

Question 25

Define heating units. How are they calculated?

Answer 25

Question 26

Explain cooling curves. Where is the MAXIMUM HEATING CAPACITY identified on the curve?

Answer 26

Question 27

What is normal line voltage? What is the role of a compensator?

Answer 27

Question 28

Give an overview of the flow of energy through an X-ray unit

Answer 28

Question 29

Comparing cylinders, cones and aperture diaphragms, which device reduces penumbra the most?

Answer 29

Question 30

Detail the components of the Image Intensifier. Describe the layers of the INPUT SCREEN and their roles.

Answer 30

Question 31

Describe features of the II output phosphor

Answer 31

Question 32

Describe 4 types of grid

Answer 32

Question 33

Detail grid ratio and grid frequency. How are both calculated?

Answer 33

Question 34

List two ways that grids can influence image

Answer 34

Question 35

Describe air-gap radiography and effects on image

Answer 35

Question 36

What are the two types of fluroscopy unit used?

Answer 36

Question 37

Detail magnification radiography

Answer 37

Question 38

Detail how CR systems work

Answer 38

Question 39

Describe the 3 main DR systems: 2 indirect and 1 direct. REMEMBER MATERIALS!!!

Answer 39

Question 40

Describe TFT

Answer 40

Question 41

Describe CCD

Answer 41

Question 42

Know your indirect and direct DR systems! Think about the diagram

Answer 42

Question 43

Describe effects of pixel, detector and matrix size on image quality

Answer 43

Question 44

Describe factors affecting spatial resolution in CR and DR systems. How is spatial resolution quantified?

Answer 44

Question 45

Describe dynamic range

Answer 45

Question 46

Describe noise

Answer 46

Question 47

Describe MTF

Answer 47

Question 48

Define DQE

Answer 48

Question 49

Describe some of the more common processing / postprocessing techniques. Describe some filters!

Answer 49

Question 50

Describe Look up tables

Answer 50

Question 51

Describe characteristic curves, including concepts of film speed and exposure latitude

Answer 51

Question 52

Describe differences between subject, film and radiographic contrast

Answer 52

Question 53

Define differences between OPTICAL DENSITY, RADIOGRAPHIC DENSITY, as well as film fog and Base optical density

Answer 53

Question 54

Describe quantitative measures of spatial resolution. How are full width half max measurements (FWHM) calculated?

Answer 54

Question 55

BRIEFLY explain Nyqvist frequency -\> how is it relevant to detector pitch and spatial resolution?

Answer 55

- SMALLEST STRUCTURE that can be detected is 50% the size of a detector element

Question 56

Compare mAs and kVp. What is the rule of thumb regarding changes to kVp?

Answer 56

Question 57

Describe relationships between kVp and mAs with RADIOGRAPHIC AND OPTICAL DENSITY. Also relationship with contrast

Answer 57

REMEMBER -\> kV DICTATES CONTRAST! mA dictates film blackness