Chapter 10 & 12 Quiz

Question 1

Amorphous silicon is used as the:

a.) photoconductor for indirect capture DR imaging
b.) photoconductor for direct capture DR imaging
c.) photodetector for direct capture DR imaging
d.) photodetector for indirect capture DR imaging

Answer 1

d.) photodetector for indirect capture DR imaging

Question 2

What are the effects of scattered radiaiton on a radiographic image?

1.) it produces fog
2.) it increases contrast
3.) it increases grid cutoff

a.) 1 and 2 only
b.) 1, 2 and 3
c.) 1 only
d.) 2 only

Answer 2

c.) 1 only

Question 3

A latent image describes:

a.) the number of photons leaving the patient
b.) interactions with xray photons and an imaging plate
c.) release of energy from fluorohalides
d.) stored energy with flurohalides

Answer 3

d.) stored energy with flourohalides

Question 4

Which grid error is the result of the CR not being aligned side to side with an IR?

a.) upside down
b.) off level
c.) off focus
d.) off center

Answer 4

d.) off center

Question 5

What type of grid design is used mainly in the xray suite?

a.) focused grids
b.) generally 6:1 grids
c.) grids with a lower ratio
d.) parallel (non focused) grids

Answer 5

a.) focused grids

Question 6

Characteristics of high ratio focused grids, compared with lower ratio grids include which of the following?

1.) they allow more positioning latitude
2.) theyre more efficient in collecting detail (SR)
3.) they absorb more of the useful beam

a.) 1 and 2 only
b.) 1, 2 and 3
c.) 2 and 3 only
d.) 1 only

Answer 6

c.) 2 and 3 only

Question 7

According to NCRP regulations, leakage radiation from the xray tube must not exceed:

a.) 10mR/h
b.) 10 mR/min
c.) 100mR/h
d.) 100 mR/min

Answer 7

c.) 100 mR/h

Question 8

Which of the following grid patterns will result in an image with the least amount of grid cutoff?

a.) cross hatched grid
b.) parallel grid
c.) focus grid
d.) crossed grid

Answer 8

c.) focus grid

Question 9

Which of the following are considered beam restricting devices? (choose all that apply)

a.) a cone
b.) a cylinder
c.) flat lead sheilding
d.) diaphragm aperture

Answer 9

a.) a cone
b.) a cylinder
d.) diaphragm aperture

Question 10

What is the main advantage of the use of a moving over a stationary grid?

a.) grid lines will be more visible with a moving grid
b.) grid lines will be blurred and not visible with a moving grid
c.) a moving grid will produce higher contrast images
d.) a moving grid is more efficient at absorbing scatter radiation

Answer 10

b.) grid lines will be blurred and not visible with a moving grid

Question 11

Which situation is most likely to result in grid errors?

a.) mobile radiography
b.) stationary radiography at the table bucky
c.) table top radiography
d.) stationary radiography in an upright bucky

Answer 11

a.) moble radiography

Question 12

Benefits of beam restrictions include: (choose all that apply)

a.) decreasing patient dose
b.) increasing FOV
c.) reducing the production of scatter
d.) limiting the area exposed to radiation

Answer 12

a.) decreasing patient dose
c.) reducing the production of scatter
d.) limiting the area exposed to radiation

Question 13

The fill factor of a detector element is the:

a.) full dimensions of the detector
b.) xray sensitive portion of the detector
c.) TFT of a detector
d.) storage capacitor of the detector

Answer 13

b.) xray sensitive portion of the detector

Question 14

An image demonstrating many brightness levels, or shades of gray, with only slight differences between the levels/shades is said to possess:

1.) long scale contrast
2.) low contrast
3.) short scale contrast

a.) 1 and 2 only
b.) 1 only
c.) 2 only
d.) 2 and 3 only

Answer 14

a.) 1 and 2 only

Question 15

The greatest detail sharpness is obtained by using
1.) a small focal spot
2.) the longest SID
3.) the smallest OID
4.) longer exposure times

a.) 1 only
b.) 1, 2 and 3
c.) 4 only
d.) 1, 2, 3 and 4

Answer 15

b.) 1, 2 and 3

Question 16

Types of grid errors include:

a.) off center error
b.) upside down focused grid
c.) off focus error
d.) off level error

Answer 16

a.) off center error
b.) upside down focused grid
c.) off focus error
d.) off level error

Question 17

The height of the lead strips within a radiographic grid compared to the distance between them is described as the:

a.) grid conversion
b.) grid ratio
c.) grid frequency
d.) grid efficiency

Answer 17

b.) grid ratio

Question 18

What is the main effect of grid cut off?

a.) overexposure to the IR
b.) reduced image resolution
c.) decreased image contrast
d.) under exposure to the IR

Answer 18

d.) under exposure to the IR

Question 19

Decreasing mAs will:

a.) increase IR exposure
b.) decrease spatial resolution
c.) decrease IR exposure
d.) increase contrast

Answer 19

c.) decrease IR exposure

Question 20

How does adding filtration to the xray tube assembly change the characterisitics of the xray beam?

a.) decreases quantity, increases quality
b.) increases quantity, decreases quality
c.) decreases quantity, decreases quality
d.) increases quantity, increases quality

Answer 20

a.) decreases quantity, increases quality

Question 21

WHich of the following types of grids will allow for the least amount of centering and or positionign latitude?

a.) 16 to1
b.) 12 to 1
c.) 5 to 1
d.) no grid

Answer 21

a.) 16 to 1

Question 22

What describes the number of lead lines per unit length?

a.) grid ratio
b.) grid height
c.) grid frequency
d.) grid convergence

Answer 22

c.) grid frequency

Question 23

Graphical representation of a set of data that represents pixel values according to IR exposure.

Answer 23

Histogram

Question 24

A process where the computer analyzes the histogram and compares it to a preestablished histogram.

Answer 24

Histogram analysis

Question 25

A digital process that adjusts the original histogram to match the expected histogram of a radiograph. This process adjusts for lsight under or over exposure to an IR.

Answer 25

Rescaling

Question 26

A processing function that will adjust the contrast of a radiograph.

Answer 26

Look Up Table

Question 27

The primary purpose of an analogue to digital converteer (ADC) to convert:

a.) xrays into a light signal
b.) electrical signals into digital signals
c.) electrical signals to xray energy
d.) light photons into an electrical signal

Answer 27

b.) electrical signals into digital signals

Question 28

Which term is used to describe the recommended range of SIDs that can be used with a specific grid?

a.) convergent point
b.) convergent line
c.) focal range
d.) focal distance

Answer 28

c.) focal range

Question 29

The primary cause of scatter radiation within a radiographic image is :

a.) photon transmission
b.) compton interactions
c.) photoelectric interactions
d.) classical interactions

Answer 29

b.) compton interactions

Question 30

A grid usually is used in which of the following circumstances?
1.) when radiographing a large or dense body part
2.) when using a high kvp
3.) when a lower patient dose is required

a.) 1, 2 and 3
b.) 1 only
c.) 1 and 2 only
d.) 3 only

Answer 30

c.) 1 and 2 only

Question 31

Which type of grid cutoff is the only one that can be demonstrated with both focused and non focused grids?

a.) upside down grid
b.) off center grid
c.) off focus grid
d.) off level grid

Answer 31

d.) off level grid

Question 32

As collimation increases, the quantity of scatter radiation decreases.

a.) true
b.) fasle

Answer 32

a.) true

Question 33

Which of the following statements best describes a focused grid?

a.) lead strips are perpendicular to each other
b.) lead strips are closer together in focused grids
c.) lead strips are angled to match the divergence of the xray beam
d.) two sets of lead strips are present at 90 degrees to each other

Answer 33

c.) lead strips are angled to match the divergence of the xray beam

Question 34

the relationship between a DEL and SR is:

a.) inversely proportional to the square
b.) inversely proportional
c.) directly proportional to the square
d.) directly proportional

Answer 34

d.) directly proportional