Brainscape's Knowledge GenomeTM

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


See full index

RT 204 > 3. Density > Flashcards

3. Density Flashcards

1
Q

2 photographic properties in assessing density

A

Density,

Visibility of detail

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

is one of the 2 photographic properties that comprise visibility of detail

A

Density

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

refers to the fact that the image is
visible to the human eye only because sufficient density
(and contrast) exists to permit the structural details to be
perceived

A

Visibility of detail

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

the degree of
overall blackening from the black metallic silver deposited
in the emulsion of film

A

traditional definition of density

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

describes the concept of density as it displayed

on a soft-copy monitor for digital images

A

Brightness

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

describes the digital processing that

produces changes in density/brightness, so it also appropriate to use when controlling image density

A

Window level

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

The majority consideration in assessing density is
verification that proper densities are ______ throughout the
anatomical area of interest on the image

A

visible

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

_______ and a _______ are the

primary tools of the radiographer when evaluating density

A

Common sense,

trained professional eye

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

Information is recorded on an image that is ________
but may not exist at all on a radiograph that is
________

A

overexposed,

underexposed

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

The _______ image has not received the information
in the first place and is not capable of being manipulated to
reveal details that were never recorded

A

underexposed

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

Whenever a choice must be made between excess and
insufficient density, the wise decision is always the choice
that will produce the _______ image

A

overexposed

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

device used to see details of overexposed image but makes it darker

A

hot/bright light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

affects visibility

A

density

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

acceptance limits

A

diagnostic value

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

The effects of mAs and other influencing factors on density
are ______ because of the multiple variables that are part
of the imaging system

A

not exact

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

Density changes can sometimes be seen from only a slight

nonlinearity in the _______

A

intensifying screen phosphor response curve,
film silver halide response,
thermionic emission of the x-ray tube filament

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

When unexpected density changes exceed the ____
necessary to become visible, they seldom place the image
outside the _______

A

30%,

acceptance limits

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

2 factors affecting density

A

controlling factors,

influencing factors

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

controlling factor of density

A

mAs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

expresses the relationship between exposure and density

A

D log E sensitometric curve or a digital response curve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

important region of the D log E curve in assessing density

A

Toe,

Shoulder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

overexposed region

A

Shoulder region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

underexposed region

A

Toe region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

it is where large changes in exposure results in small changes in OD (optical density)

A

Toe and shoulder region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

A common misnomer on radiography is that doubling the

exposure will ____ the film density

A

double

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

For digital image receptor systems, changes in _____ no

longer control density

A

mAs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

For digital image receptor systems, Image density/brightness on the
display monitor is controlled by ______

A

window levelling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

are graphic representations of the

exposure to the image receptor

A

Digital image histograms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

is use as the primary controller of

image receptor exposure and film density

A

mAs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

is primarily determined by the amount of

exposure a receptor receives

A

density

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

is directly proportional to mAs

A

exposure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

The minimum change necessary to cause a visible shift in
film density is _____ of mAs, or any other influencing factors
that would equal this change.

A

30%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Various authors over the years have set the minimum for a

visible density change at values between ______ of mAs

A

25-35%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

The general rule of thumb for mAs changes is to make

adjustments in _______

A

increments or doubles or halves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

mAs is incremented by

A

decimals

36
Q

Influencing Factors of Density:

A 
kVp,
Focal Spot Size,
Anode Heel Effect,
Distance (SID and OID),
Filtration,
Beam Restriction,
Anatomical Part,
Grids,
Image Receptor,
Film processing
37
Q

alters the intensity of the beam reaching the

image receptor in two ways

A

kVp

38
Q

a change in _______ alters the intensity of

the beam when the mAs and other factors remain the same

A

kilovoltage

39
Q

Both the quantity and quality of the x-ray beam will vary

significantly with changes in _______

A

kilovoltage

40
Q

A visible change in film density can usually be detected
with a _____ change in kVp in the lower ranges (30-50 kVp)
but an _____ change is required in the middle ranges (50-90
kVp), and a ____ change in the higher ranges (90-130
kVp)

A

4-5%,
8-9%,
10-12%

41
Q

the radiographer must have a method of using kilovoltage to adjust and compensate for film density changes, the rough guide known as the _______ has been developed

A

15 percent rule

42
Q

is another important

consideration in how kVp affects image receptor exposure/film density

A

configuration of the generator

43
Q

utilize a greater

incident electron stream than small focal spots

A

Larger focal spots

44
Q

The actual mA for a large focal spot is ____ than the actual
mA received when set at 100 mA for a small focal spot.

A

less

45
Q

will heat up fast but makes the image sharper

A

Short Focal Spot Size

46
Q

takes time to heat up but creates penumbra

A

Large Focal Spot Size

47
Q

Large focal spots tend to bloom more at _____
milliamperages and may occasionally reach a point where
they alter the image receptor exposure

A

higher

48
Q

Because properly calibrated units will not exhibit film
density changes when focal spots are changed, differences of
this type should be reported as a ______

A

quality control procedure

49
Q

alters the intensity of radiation and

therefore the density, between the anode and cathode ends of the x-ray tube

A

Anode Heel Effect

50
Q

is more pronounced when the
collimator is open wide than when it is closed because of a
greater portion of the peripheral beam

A

Anode Heel Effect

51
Q

The anode heel effect is more pronounced when the
collimator is open wide than when it is closed because of a
greater portion of the peripheral beam, and therefore a
greater portion of the intensity difference, reaches the IR
when the collimator is _____

A

wide open

52
Q

When the anode heel effect becomes apparent, it can be ______

A

minimized or converted to an advantage

53
Q

Anode heel effect
is _______ by collimating the beam and eliminating as
much of the intensity difference at the periphery as possible.

A

minimized

54
Q

The anode heel effect may be _______
in examinations of objects with greater subject density at
one end than at another

A

converted to an advantage

55
Q

alters the intensity of the beam reaching the image receptor, according to the inverse square law

A

Source-to-Image receptor

Distance

56
Q

affects exposure in inverse

proportion to the square of the distance

A

inverse square law

57
Q

expresses the change in

intensity when the distance changes

A

inverse square law formula

58
Q

the most common situation in radiography is a need to maintain an _______ image receptor exposure/film density while changing the distance

A

acceptable

59
Q

is only accurate within a

moderate acceptance range

A

exposure maintenance formula

60
Q

The _______ of some
components in the imaging system makes it impossible to
exactly quantify the relationship between radiation beam
intensity and film density

A

nonlinearity

61
Q

Distance doubling and halving will bring image receptor
exposure within roughly ____ of the original exposure and
usually within image acceptance limits

A

50%

62
Q

3 Cardinal Principles of Radiation Protection

A

Time,
Distance,
Shielding

63
Q

has an effect on image

receptor exposure/film density.

A

Object-to-Image receptor (OID)

64
Q

increase OID can ______ density

A

decrease

65
Q

its ability to alter beam intensity affect

image receptor exposure and film density

A

Filtration

66
Q

reduces the total

number of photons available

A

Restricting the beam, collimating, or

reducing the primary beam field size

67
Q

dramatically increased with large

anatomical size and high starting kVp levels

A

Scatter production

68
Q

Technical factor compensation for changes in film density is

required only under the following circumstances:

A
  1. ) Large anatomical part
  2. ) High kilovoltage
  3. ) Low grid efficiency
  4. ) Nongrid examinations
69
Q

is the prime

attenuator of the beam

A

Patient

70
Q

Because the patient is the prime
attenuator of the beam, the _________ being examined has a great deal of influence on image receptor
exposure and film density

A

anatomical part

71
Q

There is an _______ relationship between tissue thickness/type and image receptor exposure/film density

A

inverse

72
Q

absorb scatter, which would otherwise add

exposure to the image receptor and density to the film

A

Grids

73
Q

(Grids) factors that reduce image receptor exposure/film density

A

Grids with high ratios,
low frequency and dense interspace material;
moving grids and improperly used grids

74
Q

HTD

A

Height of the grid (H),
Thickness of the grid strip (T),
Width of the Interspace material (D)

75
Q

Grid ratio

A

h/D

76
Q

the primary purpose of a grid is the _________

A

improvement

of contrast

77
Q

compensating for film density changes by
varying the kVp is ______ because it may change
the contrast in the opposite direction, thus negating the
reason for using the grid in the first place

A

not recommended

78
Q

when using grids, do not change ____

A

kVp

79
Q

Both film and intensifying screens alter film density

A

Image Receptor

80
Q

When the silver halide crystals in the film emulsion form
________, they establish the physical foundation
for the black metallic silver that is the definition of density

A

latent image centers

81
Q

are the most useful

parameters for intensifying screen combinations

A

Relative Speed (RS) numbers

82
Q

As relative speed increases, the amount of exposure required to maintain the same film density ______

A

decreases

83
Q

Digital radiographic systems can be _____ in their sensitivity to the income of x-ray photons

A

varied

84
Q

The condition of the ________ solutions can dramatically alter film density

A

film processing

85
Q

Film density will increase when the ______ (Film processing)

A

developer solution temperature increases, immersion time increases or
replenishment rates increase

86
Q

With Grid, _____ Contrast, _____ Density

A

Increase C,

Decrease D

RT 204 (11 decks)

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