3. Density

Question 1

2 photographic properties in assessing density

Answer 1

Density,

Visibility of detail

Question 2

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

Answer 2

Density

Question 3

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

Answer 3

Visibility of detail

Question 4

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

Answer 4

traditional definition of density

Question 5

describes the concept of density as it displayed

on a soft-copy monitor for digital images

Answer 5

Brightness

Question 6

describes the digital processing that

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

Answer 6

Window level

Question 7

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

Answer 7

visible

Question 8

_______ and a _______ are the

primary tools of the radiographer when evaluating density

Answer 8

Common sense,

trained professional eye

Question 9

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

Answer 9

overexposed,

underexposed

Question 10

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

Answer 10

underexposed

Question 11

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

Answer 11

overexposed

Question 12

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

Answer 12

hot/bright light

Question 13

affects visibility

Answer 13

density

Question 14

acceptance limits

Answer 14

diagnostic value

Question 15

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

Answer 15

not exact

Question 16

Density changes can sometimes be seen from only a slight

nonlinearity in the _______

Answer 16

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

Question 17

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

Answer 17

30%,

acceptance limits

Question 18

2 factors affecting density

Answer 18

controlling factors,

influencing factors

Question 19

controlling factor of density

Answer 19

mAs

Question 20

expresses the relationship between exposure and density

Answer 20

D log E sensitometric curve or a digital response curve

Question 21

important region of the D log E curve in assessing density

Answer 21

Toe,

Shoulder

Question 22

overexposed region

Answer 22

Shoulder region

Question 23

underexposed region

Answer 23

Toe region

Question 24

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

Answer 24

Toe and shoulder region

Question 25

A common misnomer on radiography is that doubling the | exposure will ____ the film density

Answer 25

double

Question 26

For digital image receptor systems, changes in _____ no | longer control density

Answer 26

mAs

Question 27

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

Answer 27

window levelling

Question 28

are graphic representations of the | exposure to the image receptor

Answer 28

Digital image histograms

Question 29

is use as the primary controller of | image receptor exposure and film density

Answer 29

mAs

Question 30

is primarily determined by the amount of | exposure a receptor receives

Answer 30

density

Question 31

is directly proportional to mAs

Answer 31

exposure

Question 32

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.

Answer 32

30%

Question 33

Various authors over the years have set the minimum for a | visible density change at values between ______ of mAs

Answer 33

25-35%

Question 34

The general rule of thumb for mAs changes is to make | adjustments in _______

Answer 34

increments or doubles or halves

Question 35

mAs is incremented by

Answer 35

decimals

Question 36

Influencing Factors of Density:

Answer 36

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

Question 37

alters the intensity of the beam reaching the | image receptor in two ways

Answer 37

kVp

Question 38

a change in _______ alters the intensity of | the beam when the mAs and other factors remain the same

Answer 38

kilovoltage

Question 39

Both the quantity and quality of the x-ray beam will vary | significantly with changes in _______

Answer 39

kilovoltage

Question 40

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)

Answer 40

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

Question 41

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

Answer 41

15 percent rule

Question 42

is another important | consideration in how kVp affects image receptor exposure/film density

Answer 42

configuration of the generator

Question 43

utilize a greater | incident electron stream than small focal spots

Answer 43

Larger focal spots

Question 44

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

Answer 44

less

Question 45

will heat up fast but makes the image sharper

Answer 45

Short Focal Spot Size

Question 46

takes time to heat up but creates penumbra

Answer 46

Large Focal Spot Size

Question 47

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

Answer 47

higher

Question 48

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

Answer 48

quality control procedure

Question 49

alters the intensity of radiation and | therefore the density, between the anode and cathode ends of the x-ray tube

Answer 49

Anode Heel Effect

Question 50

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

Answer 50

Anode Heel Effect

Question 51

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 _____

Answer 51

wide open

Question 52

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

Answer 52

minimized or converted to an advantage

Question 53

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

Answer 53

minimized

Question 54

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

Answer 54

converted to an advantage

Question 55

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

Answer 55

Source-to-Image receptor | Distance

Question 56

affects exposure in inverse | proportion to the square of the distance

Answer 56

inverse square law

Question 57

expresses the change in | intensity when the distance changes

Answer 57

inverse square law formula

Question 58

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

Answer 58

acceptable

Question 59

is only accurate within a | moderate acceptance range

Answer 59

exposure maintenance formula

Question 60

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

Answer 60

nonlinearity

Question 61

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

Answer 61

50%

Question 62

3 Cardinal Principles of Radiation Protection

Answer 62

Time, Distance, Shielding

Question 63

has an effect on image | receptor exposure/film density.

Answer 63

Object-to-Image receptor (OID)

Question 64

increase OID can ______ density

Answer 64

decrease

Question 65

its ability to alter beam intensity affect | image receptor exposure and film density

Answer 65

Filtration

Question 66

reduces the total | number of photons available

Answer 66

Restricting the beam, collimating, or | reducing the primary beam field size

Question 67

dramatically increased with large | anatomical size and high starting kVp levels

Answer 67

Scatter production

Question 68

Technical factor compensation for changes in film density is | required only under the following circumstances:

Answer 68

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

Question 69

is the prime | attenuator of the beam

Answer 69

Patient

Question 70

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

Answer 70

anatomical part

Question 71

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

Answer 71

inverse

Question 72

absorb scatter, which would otherwise add | exposure to the image receptor and density to the film

Answer 72

Grids

Question 73

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

Answer 73

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

Question 74

HTD

Answer 74

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

Question 75

Grid ratio

Answer 75

h/D

Question 76

the primary purpose of a grid is the _________

Answer 76

improvement | of contrast

Question 77

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

Answer 77

not recommended

Question 78

when using grids, do not change ____

Answer 78

kVp

Question 79

Both film and intensifying screens alter film density

Answer 79

Image Receptor

Question 80

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

Answer 80

latent image centers

Question 81

are the most useful | parameters for intensifying screen combinations

Answer 81

Relative Speed (RS) numbers

Question 82

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

Answer 82

decreases

Question 83

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

Answer 83

varied

Question 84

The condition of the ________ solutions can dramatically alter film density

Answer 84

film processing

Question 85

Film density will increase when the ______ (Film processing)

Answer 85

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

Question 86

With Grid, _____ Contrast, _____ Density

Answer 86

Increase C, | Decrease D