Deck 17: Digital Radiographic Technique

Question 1

Screen-film radiography has a dynamic range of _____.

A) 10
B) 100
C) 1,000
D) 10,000

Answer 1

1,000

Question 2

If there were such thing as a perfect imaging system,the MTF would be equal to _____.

A) 5
B) 1
C) 2
D) 4

Answer 2

1

Question 3

As spatial frequency increases the object size _____ and the spatial resolution _____.

A) increases, increases
B) decreases, decreases
C) decreases, increases
D) increases, decreases

Answer 3

decreases, increases

Question 4

Recent studies have shown that denser breast tissue is best imaged with _____.

A) xerography
B) computed tomography
C) screen-film mammography
D) digital mammography

Question 5

As mAs is increased the signal to noise ratio is _____.

A) decreased
B) increased
C) not affected
D) doubled

Question 6

If a digital radiography imaging system has a spatial resolution of 10 lp/mm,what is the pixel size of that system?

A) 0.05 mm
B) 0.5 mm
C) 0.1 mm
D) 0.01 mm

Question 7

The use of two screens in imaging results in a higher _____.

A) spatial frequency
B) pixel size
C) MTF
D) spatial resolution

Question 8

The bit capacity of each pixel identifies the _____ of a digital imaging system.

A) dynamic range
B) grey scale
C) spatial frequency
D) MTF

Question 9

Of all radiographic imaging systems,_____ has the best contrast resolution.

A) digital radiography
B) mammography
C) magnetic resonance imaging
D) computed tomography

Question 10

A _____ test tool is used to acquire data for an MTF curve.

A) bar pattern
B) post processing
C) signal-to-noise ratio
D) contrast-detail curve

Question 11

The two principal characteristics of a medical image are _____.

A) spatial resolution and noise
B) spatial resolution and contrast resolution
C) contrast resolution and modular transfer function
D) contrast resolution and dynamic range

Question 12

The number of gray shades that an imaging system can reproduce is called its _____.

A) spatial frequency
B) contrast
C) spatial resolution
D) dynamic range

Question 13

What is the spatial frequency of a digital system that can resolve 100 um?

A) 5 lp/mm
B) 10 lp/mm
C) 50 lp/mm
D) 100 lp/mm

Question 14

The portion of useful image-forming x-rays is referred to as the _____.

A) frequency
B) MTF
C) signal
D) noise

Question 15

The _____ digital imaging system uses the highest dynamic range.

A) computed tomography
B) mammography
C) magnetic resonance
D) angiography

Question 16

Spatial frequency is used to describe the quality of spatial resolution in terms of _____.

A) pixel size
B) modular transfer function
C) line pairs
D) contrast resolution

Question 17

In digital imaging,spatial resolution is ultimately limited by _____.

A) focal spot size
B) spatial frequency
C) contrast resolution
D) pixel size

Question 18

If a digital system has a spatial resolution of 4 lp/mm,it can resolve an object as small as _____ mm.

A) 8
B) 4
C) 0.25
D) 0.125

Question 19

The human visual system can distinguish _____ shades of gray.

A) 10
B) 30
C) 300
D) 1000

Question 20

Image detail is also called _____.

A) spatial resolution
B) spatial frequency
C) signal to noise ratio
D) dynamic range

Question 21

The use of an image receptor with _____ DQE can result in _____ patient doses.
I. low,lower
II. high,lower
III. high,higher
IV. low,higher

A) I
B) II
C) I & III
D) II & IV

Question 22

DQE is _____.

A) density quantum effect
B) direct quantum efficiency
C) detective quantum efficiency
D) detective quantum energy

Question 23

With digital imaging,patient dose can be reduced by using higher _____ techniques.

A) mAs
B) kVp
C) optical density
D) contrast

Question 24

Digital radiography images should be repeated if there is a problem with _____.

A) contrast
B) overexposure
C) brightness
D) none of the above

Question 25

If an image receptor has a high probability of interacting with the x-ray beam,then it has a high _____.

A) DQE
B) SNR
C) MTF
D) lp/mm