221 Final review

Question 1

With digital imaging, patient dose can be reduced by using higher___.

Answer 1

kVp

Question 2

In digital imaging, spacial resolution is ultimately limited by ____.

Answer 2

pixel size

Question 3

Overexposure in digital radiography results in ___.

Answer 3

plate saturation and decreases contrast

Question 4

A different x-ray unit must be bought to take digital x-rays
T/F

Answer 4

False

Question 5

This type of digital radiography requires a cassette and processor.

Answer 5

Computed Radiography

Question 6

What is the cause of most retakes in digital radiography?

Answer 6

Poor positioning

Question 7

T/F - kVp does not control contrast on a digital image?

Answer 7

True

Question 8

In digital imaging, brightness is called…?

Answer 8

Window Level

Question 9

What is noise in digital imaging?

Answer 9

exposure and scatter

Question 10

Backscatter on a digital image can cause an artifact called___

Answer 10

Phantom image artifact

Question 11

When are film intensifying screens used?

Answer 11

Conventional

Question 12

Intensifying screens do what?

Answer 12

emit light when struck by x-rays

Question 13

CR aquires a image through the use of

Answer 13

storage phosphor plates

Question 14

In the DR system, what is need to produce the radiographic image?

Answer 14

CCD, x-ray absorber

Question 15

What is the x-ray absorber in DR?

Answer 15

photoconductor

Question 16

It takes ___ seconds to aquire the image in conventional and only ___ seconds in DR.

Answer 16

90 and 3-5

Question 17

What is active element in storage phosphor plate?

Answer 17

Barium Fluorohalide

Question 18

What is scanned over the phosphor plate to release the image?

Answer 18

focus laser light

Question 19

Sequence for PSP image capture?

Answer 19

Phosphor plates, focus laser light scanner, photomultiplier, analog digital converter, review station

Question 20

The two elements needed to convert light signals into an electrical signal while using indirect capture DR are TFT and

Answer 20

photodiodes

Question 21

X-ray energy related to direct capture Dr will stimulate a _______ which eventually is changed into an electrical signal

Answer 21

Scintillator

Question 22

What does a photoconductor do?

Answer 22

converts energy into a digital electric signal

Question 23

Exposure latitude in conventional rad is equivalent to what in DR?

Answer 23

Dynamic range

Question 24

Optical density is primarily controlled by ___ in CR.

Answer 24

mAs

Question 25

What are examples of preset image annotations?

Answer 25

date and time

Question 26

T/F - When switching from a conventional diagnostic radiography room to one that incorporates CR, major equipment changes are to be expected

Answer 26

False

Question 27

T/F - Indirect capture DR converts absorbed x-ray energy into visible light

Answer 27

True

Question 28

Is the Bucky required?

Answer 28

No, just recommended

Question 29

T/F - Changing the matrix and field of view does not change the pixel size

Answer 29

False

Question 30

What is each square in a matrix called?

Answer 30

picture element

Question 31

What is bit depth?

Answer 31

Number of bits per pixel

Question 32

What does exposure index refer to?

Answer 32

Amount of radiation to the IR

Question 33

What is deviation index?

Answer 33

The difference between the actual exposure and the target exposure

Question 34

What is the result in the failure or reader to identify collimated edges?

Answer 34

misinterpretation of the image and will be too light/dark

Question 35

How does kvp affect the histogram?

Answer 35

Makes it narrow

Question 36

The ability to respond to varying levels of exposure

Answer 36

dynamic range