Chapter 13 - Screen Film Radiographic Technique

Question 1

What are the 4 main exposure factors?

Answer 1

Kilovoltage peak (kVp)
Miliamperage (MA)
Time (fractions of seconds)
Source Image Distance (SID)

Question 2

Ability for the beam to penetrate

Answer 2

X-ray beam quality

Question 3

KVp controls what 3 things?

Answer 3

X-ray beam quality (ability for beam to penetrate)

Reduces quantity (of xray production to a lesser degree - directly related)

Image contrast - absorption is decreased as kVp increases therefore contrast decreases

Question 4

Absorption is ____ as kVp increases therefore contrast ____

Answer 4

Decreased

Decreases

Question 5

What determines how many xrays are produced?

Answer 5

Miliamperage

Question 6

Only xray beam ____ is affected by changes in miliamperage or time

Answer 6

Quantity

Question 7

Determines the area impacted by projectile electrons

Answer 7

Focal spot size

Question 8

Fixed amount of filtering that is built into xray machine. (Some occurs passing through envelope of tube)

Answer 8

Inherent filtration

Question 9

Additional al or leaded plexiglass filters attached to the columninator

Answer 9

Added filtration

Question 10

What are the 3 basic types of high voltage generation?

Answer 10

Single phase
3 phase
High frequency

Question 11

What happens when frequency is increased?

Answer 11

Voltage ripple is reduced
x-ray production is more efficient
Patient dose decreases

Question 12

What are the 4 patient factors?

Answer 12

Body Habitus
Part thickness
Composition of tissue
Pathology

Question 13

Over exposed = too ____

Under exposed = too ____

Answer 13

Black

White

Question 14

What is the primary control of optical density?

Answer 14

MAS

Question 15

What is the 15% rule?

Answer 15

A 15% increase in KVp will approximately double exposure of image receptor

Question 16

What are the two components of resolution?

Answer 16

Spatial resolution

Contrast resolution

Question 17

Line pairs per mm

Answer 17

Spatial resolution

Question 18

Ability to produce perceptive difference between background and object

Answer 18

Contrast resolution

Question 19

Image “sharpness” is most often a reference to what type of resolution?

Answer 19

Spatial resolution

Question 20

Spatial resolution of x-ray film is ____ than the resolution of the ____ ____

Answer 20

Greater, intensifying screen

Question 21

What are the 4 components of noise?

Answer 21

Film grain
Structure mottle
Quantum mottle
Scatter