Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Exposure > Ch. 23 - Digital Equipment (Exp I & II) > Flashcards

Ch. 23 - Digital Equipment (Exp I & II) Flashcards

1
Q

Digital radiography (DR) is characterized by…

A

The use of reusable receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Computers operate using a ______ language.

A

Binary machine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Each binary number is called a…

A

Bit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

An eight-bit word is called a…

A

Byte

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

When the main power to the computer is turned off, ____ is erased.

A

RAM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

When the main power to the computer is turned off, ____ is maintained.

A

ROM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Computed radiography is also referred to as…

A

PSP technology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Indirect DR uses _______ as the detector material.

A

Amorphous silicon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

CR systems acquire clinical information by…

A

Laser scanning a PSP plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The window width controls…

A

Image contrast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The window level controls…

A

Brightness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Window width changes are sometimes called…

A
  • Gray scale expansion
  • Enhancing visibility of detail
  • Gray scale compression
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Resolution is controlled by ____ size.

A

Pixel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

A common feature between indirect and direct DR technology is…

A

Thin film technology (TFT)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Computerized digital images consist of a ____ of picture elements, each with a video display value or gray shade.

A

Matrix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Each pixel in a digital display matrix is located according to its…

A

Electronic address

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

In digital imagine, the limiting factor in spatial resolution is the…

A

Pixel size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

A pixel that has an 8-bit depth displays ____ shades of gray.

A

256

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which of the choices below would produce the highest spatial frequency and contrast?

a. ) Gall bladder
b. ) Contrast filled urinary bladder
c. ) 3mm renal calculi (stone)
d. ) Contrast-filled appendix

A

c.) 3mm renal calculi (stone)

20
Q

Which of the following is not related to the others?

a. ) Local processing
b. ) Manual processing
c. ) Point processing
d. ) Geometric processing

A

b.) Manual processing

21
Q

In digital image processing, the digital data set is arranged into a histograph distribution in order to determine the…

a. ) Display matrix
b. ) Exposure index
c. ) Values of interest (VOI)
d. ) Both b ad c

A

d.) Both b and c

22
Q

In digital image processing, an overexposed or underexposed image can be modified to achieve an acceptable “look” through a histogram analysis. This is the result of the digital processing technique of…

a. ) Histogram stretching
b. ) Histogram modification
c. ) Rescaling
d. ) All of the above

A

d.) All of the above

23
Q

The purpose of LUT is to…

A

Apply a predetermined scale of contrast to the digital data set.

24
Q

If the radiographer applied an ankle LUT to a chest radiograph data set, the image would demonstrate…

A

High contrast

25
Q

All of the following are true of local area processing EXCEPT:

a. ) It relies on the application of kernels to pixels
b. ) Kernels are ultimately applied to the entire pixel data set
c. ) Spatial filtering is an example of local area processing
d. ) Electronic magnification of the image is an example of local area processing

A

d.) Electronic magnification of the image is an example of local area processing

26
Q

the relationship between digital image resolution…

a. ) Is direct with matrix size
b. ) Is indirect with pixel size
c. ) Is direct with pixel bit depth
d. ) Both a and b

A

d.) Both a and b

27
Q

When matrix size is increased ad pixel size goes down,

A

Spatial resolution increases

28
Q

Of the many types of digital image procedures performed in a contemporary medical imaging department, the largest file sizes are typically generated by…

A

Digital fluoroscopy

29
Q

Noise on a digital image is the summation of inherent electron system noise and quantum mottle noise. Of these two, the radiographer can improve the noise on an image by…

A

Increasing the exposure technique.

30
Q

Of the following, the best S:N ratio is

a. ) 10:1
b. ) 100:1
c. ) 500:1
d. ) 1,000:1

A

d.) 1,000:1

31
Q

When the quality of a digital detector is inspected for purchase, the preferred detector for purchase would have a…

a. ) DQE of 65% and MTF of 0.55
b. ) DQE of 40% and MTF of 0.80
c. ) DQE of 68% and MTF of 0.80
d. ) DQE of 55% and MTF of 0.35

A

c.) DQE of 68% and MTF of 0.80

32
Q

The deviation index (DI)…

A

Compares entrance dose to the detector to a reference industry-standard target dose.

33
Q

An S value of 200 represents…

A

An exposure to the IP of 1 mR

34
Q

When changing the exposure technique from 9 mAs to 18 mAs using computed radiography, the radiographer should expect…

A

An EI number increase from 1500 to 1800.

35
Q

The response to radiation exposure with a digital receptor is…

A

Linear

36
Q

Grossly overexposed digital images will demonstrate…

A

A loss of contrast

37
Q

When using CR technology, it is important to remember that…

a. ) The IP is extrasensitive to exposure after the initial x-ray exposure
b. ) The IP will lose about 25% of its signal in 8 hours if not processed
c. ) The IP is very sensitive to scatter, making grids very important
d. ) All of the above

A

d.) All of the above

38
Q

An x-ray exposure taken at 80 kVp has an average energy of…

A

35 keV

39
Q

In the technology of CR, the latent image is actually…

A

Electron “holes” in Europium

40
Q

All of the following are true of pixel pitch EXCEPT:

a. ) It is defined as the distance between pixels
b. ) It is not related to spatial resolution
c. ) Is is determined by the size of the DEL in DR systems
d. ) It is measured from the center-to-center of the pixels

A

b.) It is not related to spatial resolution

41
Q

All of the following impact digital image spatial resolution EXCEPT:

a. ) Pixel pitch
b. ) Bits/pixel
c. ) DEL dimension
d. ) Sampling frequency

A

b.) Bits/pixel

42
Q

The size of the digital file size is determined by the:

a. ) Bit depth
b. ) Pixel size
c. ) Matrix
d. ) All of the above

A

d.) All of the above

43
Q

In CR technology, pre-processing of data includes:

a. ) Histogram analysis
b. ) Gray scale analysis
c. ) Exposure data recognition (EDR)
d. ) All of the above

A

d.) All of the above

44
Q

In digital image technology, once the image data is sent to PACS…

A

The data is fixed and not able to be reprocessed.

45
Q

When using a Fuji CR system in the fixed-mode of operation:

a. ) Exposure techniques are variable and adjustable by the computer to adjust density and contrast
b. ) The system will not correct for exposure inadequacies and adjust for density problems
c. ) Your exposure techniques must be accurate, similar to film/screen technology
d. ) Both b and c

A

d.) Both b and c

46
Q

All of the following are TRUE of Moire effect EXCEPT:

a. ) It results from a conflict in spatial frequencies between the grid frequency and laser scanning frequency
b. ) It produces useless diagonal dark lines across the finished image
c. ) It is most likely to occur with DR technology, particularly amorphous selenium
d. ) It is eliminated with ultra-high grid frequencies 178-200 lpi

A

c.) It is most likely to occur with DR technology, particularly amorphous selenium

Exposure (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions