Ch. 9 Test

Question 1

Image brightness can be adjusted by adjusting:

Answer 1

window level and exposure factors

Question 2

____ can occur when an image receptor is over exposed.

Answer 2

saturation

Question 3

These are numeric values that indicate the amount of radiation an image receptor receives.

Answer 3

EI and S numbers

Question 4

The exhibited difference in brightness levels within an image.

Answer 4

contrast

Question 5

Digital imaging uses a _____ dynamic range

Answer 5

wide

Question 6

The absorption characteristics of the tissues being imaged.

Answer 6

subject contrast

Question 7

T/F - Effective atomic number has no impact on subject contrast.

Answer 7

false

Question 8

T/F - An abdomen has greater subject contrast than a chest.

Answer 8

false

Question 9

T/F - The quality of a radiographic beam effects the way it may be attenuated.

Answer 9

true

Question 10

An image of high contrast is mostly _____

Answer 10

black and white

Question 11

An image of low contrast has ____

Answer 11

lots of shades of gray

Question 12

Pixel size =

Answer 12

FOV/matrix size

Question 13

The term used to evaluate the accuracy of anatomical structural lines.

Answer 13

spatial resolution

Question 14

T/F - Pixel size is the primary factor that affects spatial resolution.

Answer 14

true

Question 15

T/F - Spatial frequency has no impact on spatial resolution.

Answer 15

false

Question 16

T/F - Larger objects have larger spatial frequency.

Answer 16

false

Question 17

The measurement of how efficiently an image receptor is in converting x-ray exposure it receives into a quality radiographic image.

Answer 17

DQE

Question 18

The measure of an imaging systems ability to display the contrast of anatomic objects varying in size.

Answer 18

MTF

Question 19

The misrepresentation of the anatomic part in imaging, resulting in an image that represents the anatomy with altered shape or size.

Answer 19

distortion

Question 20

T/F - Increasing OID reduces magnification.

Answer 20

false

Question 21

T/F - Increasing SID reduces magnification.

Answer 21

true

Question 22

T/F - Increased SID with reduced OID is ideal.

Answer 22

true

Question 23

T/F - Decreased SID with increased OID is ideal.

Answer 23

false

Question 24

T/F - It is possible to completely eliminate OID.

Answer 24

false

Question 25

T/F - The radiographer should use as much SID as possible at all times.

Answer 25

false

Question 26

T/F - Elongation means that the imaged part appears shorter than it is.

Answer 26

false

Question 27

T/F - Foreshortening means that the imaged part appears shorter than it is.

Answer 27

true

Question 28

T/F - When aligning the part to the IR, the part should always be perpendicular to the IR.

Answer 28

false

Question 29

T/F - When aligning the CR to the IR, the CR should be as close to parallel to the IR as possible.

Answer 29

false

Question 30

In general, the ___ should strike the ___ and the anatomic part perpendicularly, and the ___ should be as close to parallel with the IR as possible, to avoid shape

Answer 30

CR, IR, anatomic part

Question 31

A method of describing the strength of radiation exposure compared with the amount of noise present in a digital image.

Answer 31

SNR

Question 32

A method of describing contrast resolution compared with the amount of noise present in the image.

Answer 32

CNR

Question 33

Any unwanted brightness level in a radiographic image.

Answer 33

artifact

Question 34

T/F - Digital algorithms can correct any and all exposure errors made.

Answer 34

false

Question 35

T/F - Short dynamic range allows us to use less radiation to produce a diagnostic image.

Answer 35

false