Week 3 222 quiz

Question 1

When it comes to scatter radiation, what is it the result of?

Answer 1

Compton Interactions

Question 2

The area of collimation, pt thickness, and field size all determine what?

Answer 2

Dose - the tissue that gets exposed

Question 3

What will create the greatest amount of scatter?

Answer 3

High kvp with large field size

Question 4

What shape is a unrestricted beam?

Answer 4

round

Question 5

If the collimation is increased, what is it doing to the field size?

Answer 5

increasing and decreasing volume

Question 6

If collimation is increased, that amount that reaches the IR ___.

Answer 6

decreases

Question 7

If you go from a 14x17 IR to a 8x10 IR how do you adjust the mAs?

Answer 7

increase

Question 8

What is the most effective beam restriction device?

Answer 8

collimation

Question 9

This results in the most unsharpness.

Answer 9

aperature diaphragm

Question 10

When do we use a grid?

Answer 10

when part is thicker than 10 cm and and kvp is higher than 60

Question 11

Why do grids absorb scatter?

Answer 11

because the scatter photons travel at a angle

Question 12

What is grid frequency?

Answer 12

lines per inch

Question 13

What is grid ration?

Answer 13

height over distance

Question 14

If have a high grid ratio, what does it do to scatter?

Answer 14

increases scatter clean up and increases contrast

Question 15

why do we primarily use linear grids?

Answer 15

easier to line up when tube is at a angle

Question 16

What is the focal distance?

Answer 16

distance between the grid and convergent line

Question 17

To compensate for the reduction of radiation reaching the IR when using a grid you must increase the ____.

Answer 17

mAs

Question 18

When x-ray beam is angled along the grid strips what type of grid cut off?

Answer 18

off-level

Question 19

When grid absorbs transmitted photons due to grid misalignment

Answer 19

grid cut-off

Question 20

What is air gap technique based on?

Answer 20

increasing oid