Imaging System Characteristics

Question 1

Dual focus Tubes mm small and large:

Answer 1

small
- 0.5mm
- 0.6mm
- 1.0 mm

large
- 1.0mm
- 1.2mm
- 2.0mm

Question 2

• 0.3/1.0mm is typically used for :
• 0.1/0.3mm is typically used for:

Answer 2

• angiography and magnification procedures
• mammography

Question 3

What is Microfocus Tubes:

Answer 3

FSS of 0.3mm or less

Question 4

Large focus

Answer 4

• normal imaging
• higher mA can be impressed for larger/dense body parts

Question 5

What is the main advantage of large FSS in relation to detail?

Answer 5

Shorter exposure times to minimize motion

Question 6

Small focus

Answer 6

• given amount of electrons cover smaller area on anode
• cannot use high mA due to limited heat capacity
• used for magnificatoin radiography where detail is required
• for smaller and thinner body parts

Question 7

Filtration

Answer 7

Filtration

Question 8

X-ray beam is ___________ and ___________

Answer 8

• polyenergetic
• heterogeneous

Question 9

Filtration __________ the beam

Answer 9

hardens

• makes beam more uniform by removing softer rays

Question 10

What are the two classifications of filtration?

Answer 10

1. Inherent
2. Added

• does not have ability to manipulate

Question 11

What is inherent filtration made of?

Answer 11

glass or metal envelope (0.5mm Aluminum equivalent)

Question 12

What is added filtration?

Answer 12

mirror in collimator box (1.0mm Aluminum equivalent)

• another 1.0mm AI eq added between x-ray tube housing and collimator

Question 13

What is the total of inherent and added filtration?

Answer 13

.5mm of Inherent Filtration+ 2.0mm of Added Filtration=

2.5mm of Total Filtration AI equivalent

Question 14

Half-Value Layer (HVL)

Answer 14

• improves quality of the beam
• is the amount of material that reduce the intensity of the x-ray beam to half its original value
• used for shielding and filtration
• increase in HVL increases the quality of the beam

Question 15

Compensation Filter

Answer 15

Different shapes of Aluminum mounted under the variable light aperture (collimator)

Question 16

Compensation filter _________ intensity of x-ray beam for a more uniformed exposure to the image receptor

Answer 16

Balances

Question 17

What are the two different shapes of compensation filter?

Answer 17

1. Wedge filter
2. Trough Filter

*does have ability to manipulate

Question 18

Wedge filter is good for:

Answer 18

body parts thick on one end and thin on the other
ex) foot, hips

Question 19

Trough Filter is good for:

Answer 19

chest

Question 20

Anode Heel Effect

Answer 20

• phenomenon which intensity of x-ray beam is greater towards the cathode side of the tube
• the loss of intensity is a result of the electrons traveling farther to the anode heel portion of the target

Question 21

Where would you place the thicker part of the body?

Answer 21

At the cathode end