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RAD 107
FINAL
218
Other
03/21/2011

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Term
What is the primary purpose of radiographic film processing?
Definition
to accumulate enough black metallic silver at sensitivity specks to yield a visible image
Term
With regards to the use of film as the image receptor, what aspect is considered to be the most sensitive and variable factor in the production of a radiograph?
Definition
Radiographic film processor; chemical activity; temperature
Term
Name the four steps of film processing:
Definition
1. developing
2. fixing
3. washing
4. drying
Term
The ________ image exist in the image receptor after exposure, but prior to processing.
Definition
Latent
Term
The action of the developer is controlled by three things:
Definition
1. Reducing agents (primary agent)
2. Activator
3. Restrainor
Term
As more and more silver ions are converted to black metallic silver, what is the resulting effect on density?
Definition
more black metallic silver = more density
Term
Phenidone, a reducing agent found in developer, performs what function?
Definition
produces shades of gray quickly
Term
Hyroquinone, a reducing agent found in developer, performs what function?
Definition
produces black areas slowly
Term
Glutaraldehyde, a hardener, performs three functions:
Definition
1. controls swelling of gelatin
2. prevents abrasion during processing
3. maintains uniform film thickness
Term
As part of the processor shut down procedure the lid is removed slightly and a crack or open slot remains relative to the top of the processor. What is the purpose for venting the processor in such a manner?
Definition
prevents fixer condensation from dripping into the developer tank
Term
What is used as a solvent for both the developer and fixer solutions?
Definition
filtered and treated water
Term
how long should radiographic film be kept in a patients file? How about mammography films?
Definition
usually 5-7 years; mammography - lifetime
Term
the turnaround rollers and equipment at the bottom of each tank consists of three things:
Definition
1. master roller
2. planetary roller
3. guide shoes
Term
what type of replenishment system is in use with the processor that we have in our darkroom?
Definition
volume replenishment
Term
the circulation system performs three functions:
Definition
1. stabilizes temp
2. agitates and mixes chemistry
3. filters solutions
Term
___________ measures the characteristic response of film to exposure and processing.
Definition
sensitometry
Term
what piece of equipment is used to measure or "read" the densities put on a film by the sensitometer?
Definition
densitometry
Term
regarding optical density numbers, if 100% of light is transmitted through the film the resulting OD # is _____. If 0% of light is transmitted through the film the resultng OD # is ______
Definition
100% = 0
0% = 4
Term
______ is density on a film without exposure, or density inherent to film.
Definition
Base + Fog
Term
Base = ____
Definition
.1
Term
Base + Fog should never exceed ____ OD
Definition
.25
Term
The toe of the D log E curve is controlled by what chemical in the developer?
Definition
phenidone
Term
The area of the D log E curve between the toe and the shoulder is called what?
Definition
straight line portion or slope
Term
what is the function of the straight line portion of the curve? by this, what does it represent?
Definition
used to demonstrate the relationship to the films exposure vs. the density transmitted (the range of useful densities)
Term
The shoulder of the D log E curve is controlled by what chemical in the developer?
Definition
Hydroquinone
Term
After a film has been exposed to Dmax, what will happen to density after further exposure? What is this called?
Definition
-It will begin to lose density after further exposure
-This is called Reversal or Solarization
Term
Contrast is controlled by what chemical of the developer solution?
Definition
Hydroquinone
Term
T or F: A dark radiograph has recieved too few photons.
Definition
False
Term
T or F: A dark radiograph has recorded too much information.
Definition
True
Term
T or F: Doubling the mAs doubles the density.
Definition
True
Term
T or F: an AEC system influences mAs
Definition
True
Term
T or F: An AEC system controls time, not milliamperage
Definition
T
Term
T or F: density increases as kVp is increased
Definition
T
Term
T or F: Scatter adds density to a radiograph
Definition
T
Term
T or F: the use of a grid increases radiographic density
Definition
False
Term
T or F: As the tissue density increases, radiographic density decreases
Definition
True
Term
T or F: Only when a density change is desired, the 15% rule should be used.
Definition
False (for test purposes 30%)
Term
T or F: As SID increases, density decreases.
Definition
True
Term
T or F: As OID increases, density increase
Definition
False
Term
T or F: As filtration increase, density decreases.
Definition
True
Term
T or F: Restricting the primary beam increases density
Definition
False
Term
T or F: in digital image systems, changes in mAs no longer control density
Definition
true
Term
The density of the radiographic image is the:
Definition
-easiest prime technical factor to evaluate
-result of black metallic silver deposited on the radiograph
-degree of overall blackening
Term
the optical density range visible to the human eye is:
Definition
0.25 to 2.50
Term
the ____ factors should be used as the principal method for adjusting radiographic density
Definition
controlling
Term
the controlling factor for density is:
Definition
mA
Term
as mAs _______; exposure increases
Definition
decreases
Term
the minimum change necessary to cause a visible shift in density is ____ % of mAs.
Definition
30
Term
which generator produces the least amount of radiographic density?
Definition
single-phase, 2-pulse
Term
which generator produces the greatest amount of radiographic density?
Definition
a high-frequency generator
Term
which rule is used as a guide to maintain the same density when kVp changes?
Definition
15% rule
Term
Which factor influences the number of photons reaching the radiographic film?
Definition
mA and time
Term
which factor influences the average energy of photons reaching the radiographic film?
Definition
kVp
Term
the 15% rule changes:
Definition
density and contrast
Term
the relationship between exposure and SID is:
Definition
inversely proportional to the square of the distance
Term
the density maintenance formula mathematically resembles the:
Definition
direct square law
Term
T or F: Any change in density affects contrast
Definition
T
Term
T or F: As the differences between adjacent densities increase, the contrast decreases
Definition
False
Term
T or F: A radiograph can have contrast and no density
Definition
False
Term
T or F: A radiograph can have density and no contrast
Definition
True
Term
T or F: the range of density values that can be perceived by the human eye is called visible contrast
Definition
True
Term
T or F: Intensifying screens create an inherently lower contrast image
Definition
False
Term
T or F: As kVp increases, contrast decrease
Definition
True
Term
T or F: Increasing kVp causes density differences that were previously undetectable to become visible
Definition
False
Term
T or F: As compton scatter increases, contrast decreases
Definition
True
Term
T or F: as body part thickness decreases, contrast increases
Definition
true
Term
T or F: as field size increase, contrast increases.
Definition
false
Term
T or F: Contrast evaluation can be made only when sufficient density exists
Definition
True
Term
T or F: at the 100 kVp range, a visible change in contrast will not be perceived until kVp is changed 10% or more.
Definition
true
Term
T or F: kilovoltage controls the relationship between photoelectric versus compton interactions
Definition
true
Term
T or F: milliamere-seconds influences contrast
Definition
true
Term
T or F: as focal spot increases, contrast increases
Definition
false
Term
T or F: as grid ratio increases, contrast increases
Definition
true
Term
T or F: the primary method for adjusting contrast with digital imaging systems is through window width manipulations
Definition
true
Term
Photoelectric vs. comptons have a ratio of ____:_____
Definition
1:1
Term
The detail of a radiographic image is visible because of _____ and _____
Definition
sufficient contrast and density
Term
the difference between two adjacent densities is:
Definition
contrast
Term
a radiograph with few shades of gray exhibits
Definition
high contrast
Term
which type of radiograph provides the most information?
Definition
low contrast
Term
the controlling factor for contrast is:
Definition
kVp
Term
a radiograph that demonstrates considerable differences between densities is called:
Definition
short scale; high contrast; increased contrast
Term
a radiograph that demonstrates minimal differences between densities is called:
Definition
long scale; low contrast; decreased contrast
Term
image receptor contrast is expressed as the ___ of the D log E curve.
Definition
slope
Term
contrast decreases with:
Definition
excessive density; inadequate density; a wider range of densities
Term
As the slope of the D log E curve ____, contrast ____.
Definition
increases, increases
Term
As kVp ____, a _____ range of photon energies is produced.
Definition
increases; wider
Term
contrast increases with each of the following except:
-decrease kVp
-decreased field size
-decreased part thickness
-increased scatter
Definition
increased scatter
Term
high contrast is directly related to _____
Definition
the number of photoelectric interactions
Term
which generator type results in the greatest decrease in contrast?
Definition
high frequency
Term
which does not increase contrast?
-increasing grid ratio
-increasing the amount of irradiated tissue
-decreasing filtration
-decreasing kVp
Definition
increasing the amount of irradiated tissue
Term
The concept of contrast as it is displayed on a soft-copy monitor for digital images is described as:
Definition
dynamic range
Term
When you increase the # of photons, the number of photoelectric interactions is _______ and the penetrability of the beam is __________
Definition
increased; increased
Term
When a lower kVp is used there is (more/less) photoelectric absorption.
Definition
More
Term
When a higher kVp is used there is (more/less) Compton Scatter?
Definition
More
Term
At 40 kVp the ratio of Photoelectric:Compton is:
Definition
1:1
Term
The higher the # of the relative speed; the (faster/slower) the system
Definition
faster
Term
The slope displays:
Definition
contrast
Term
when WW is increased; contrast is:
Definition
decreased
Term
controlling factor for density
Definition
mAs
Term
influencing factor for density
Definition
kVp, distance
Term
15% rule controls _____ and influences _____
Definition
controls contrast; influences density
Term
when kVp is increased; quality and quanity are ______
Definition
increased
Term
you must increase or decrease mAs by ____% to see a visible density difference
Definition
30%
Term
what absorbs low energy photons which increases the average energy of the beam. this causes film density to decrease
Definition
filtration
Term
intensifying screens _____ contrast
Definition
improve
Term
Grids ______ density and _______ contrast
Definition
decrease density; increase contrast
Term
which automatic processor solution is most affected by contamination?
Definition
developer
Term
contrast decreases with:
-inadequate density
-excessive density
-a wider range of densities
-all of the above
Definition
all of the above
Term
the restrainer added to the developer is:
Definition
potassium bromide
Term
the primary chemical agents in the fixer are called _____ agents
Definition
clearing agents
Term
the max density that the film is able to record is the:
Definition
Dmax
Term
which type of film is pre-exposed to Dmax so that additional exposure will cause a reversal of the image?
Definition
duplication
Term
as phosphor crystal size increase, resolution ______
Definition
decreases
Term
T or F: distortion is a geometric property affecting radiographic image quality
Definition
true
Term
T or F: objects that are farthest from the image receptor are magnified
Definition
true
Term
T or F: objects that are farthest from the image receptor are minimized
Definition
false
Term
T or F: shape distortion is the misrepresentation by unequal magnification of the actual shape of the object being examined
Definition
True
Term
T or F: shape distortion is the misrepresentation by unequal magnification of the actual size of the object being examined
Definition
False
Term
T or F: changes in the tube angle cause elongation
Definition
true
Term
T or F: the long axis of the anatomical part is intended to be positioned perpendicular to the CR and parallel to the IR
Definition
T
Term
T or F: Angulation of the tube is designed to cause a controlled amount of shape distortion
Definition
True
Term
T or F: Minification and magnification are not possible in digital image receptor systems
Definition
false
Term
Distortion is a misrepresentation of:
Definition
size and shape
Term
size distortion in radiography can be ____ only.
Definition
magnification
Term
size distortion is controlled by:
Definition
SID, OID, radiographic distances
Term
As size distortion decreases, the resolution of recorded detail _______
Definition
increases
Term
The ____ the SID, the ____ the magnification
Definition
greater, smaller
Term
examinations of body parts with a large inherent OID use ___ whenever possible
Definition
large SID
Term
which exam does not exhibit any inheritly large OID
Definition
AP lumbar spine
Term
As OID increases and SID remains constant, entrance skin exposure
Definition
increases
Term
large patients receive a greater exposure than small patients because their:
Definition
SOD is decreased
OID is increased
entrance skin surface is closer to the source
Term
the magnification factor for a procedure is 1.25. It may be assumed that there is a _____ magnification of the object size
Definition
125%
Term
which occurs when the tube or the IR is not properly aligned?
Definition
elongation
Term
which occurs when the part is improperly aligned?
Definition
foreshortening
Term
Proper alignment is achieved when the CR is ____ to the part and _____ to the IR
Definition
perp and perp
Term
when the position of the patient is reversed, the direction of the tube angle must be ___ to maintain the relationship.
Definition
reversed
Term
T or F: double emulsion film must be loaded with the notch in the lower left corner
Definition
F
Term
T or F: single-emulsion film must be loaded with the emulsion toward the intensifying screen
Definition
T
Term
T or F: the gelatin found in the emulsion chimically reacts with silver halides
Definition
F
Term
T or F: double-emulsion film is sometimes called duplitized
Definition
T
Term
T or F: the supercoat is a layer of hard, protective adhesive material
Definition
false
Term
T or F: primarily, it is x-ray photons that interact with the film
Definition
false
Term
T or F: the ejected halide electron is attracted to and trapped by a sensitivity speck
Definition
T
Term
T or F: when the sensitivity speck traps a free electron, it becomes negatively charged
Definition
True
Term
A negatively charged sensitivity speck attracts a free silver cation
Definition
True
Term
When a silver cation is attracted to the negatively charged sensitivity speck, the speck is ionized.
Definition
False
Term
T or F:direct exposure film has a double emulsion
Definition
false
Term
the complete construction of diagnostic radiographic film includes:
Definition
a polyester base; an adhesive material; an emulsion
Term
qualities of a good film base include:
Definition
flexibility; stability; uniform lucency
Term
adhesive is used to:
Definition
glue the emulsion to the base
Term
emulsion is composed of gelatin and:
Definition
silver halide crystals; silver salt; photosensitive crystals
Term
The gelatin is used to:
Definition
distribute the crystals evenly over the surface of the film
Term
the photosensitive agents used in diagnostic radiographic film include silver...
Definition
bromide, chloride, iodid
Term
the most commonly used silver halide is silver:
Definition
bromide
Term
which one of the radiographic films is not a single-emulsion film?
Definition
fluoroscopic
Term
the waste product formed during crystal production is:
Definition
potassium nitrate
Term
each crystal is a cubic lattice of each of the following attoms except:
Definition
potassium
Term
the crystal lattice is bound together with which type of bond?
Definition
ionic
Term
the impurity added to the crystal lattice is:
Definition
gold-silver sulfide
Term
the impurity added to the crystal lattice is called the:
Definition
sensitivity speck
Term
the purpose of the sensitivity speck is to:
Definition
attract free silver ions
Term
which type of film is sensitive to all colors
Definition
panchromatic
Term
which photons primarily interact with the radiographic film?
Definition
light
Term
the unseen change in the atomic structure of the crystal lattice is called the ____ image
Definition
latent
Term
according to the gurney-mott theory, the incident photon interacts with one of the halides and ejects a/an:
Definition
electron
Term
a single incident photon may free ____ electrons for deposition at sensitivity specks
Definition
thousands of
Term
which type of film has the fastest speed
Definition
screen film
Term
a small crystal size will produce _____ resolution and ____ speed
Definition
high, slow
Term
radiographic film should be stored:
Definition
-at a temp below 68* F
-in 30-60 % humidity
-on end
Term
T or F: the primary reason rare-earth phosphors have gained widespread acceptance is because they offer increased speed while maintaining resolution
Definition
F
Term
T or F: to ensure max latent image formation, it is important that film sensitivity and spectral emission match
Definition
T
Term
T or F:the predominant phosphor used in intensifying screens is the rare-earth phosphor
Definition
T
Term
T or F:as conversion efficiency increases, the radiation dose to the patient increases
Definition
f
Term
T or F:a high atomic # phosphor is desirable to decrease the probability of an incident x-ray photon interaction
Definition
F
Term
T or F: intensifying screens and film exhibit the same types of characteristics
Definition
T
Term
T or F:an increase in kVp will cause a decease in screen speed
Definition
F
Term
T or F: smaller crystals and a thinner layer decrease resolution and increase speed
Definition
F
Term
T or F: the naked eye can resolve approximately 50 lp/mm
Definition
F
Term
to eliminate quantum mottle
Definition
increase mAs
Term
intensifying-screen resolution is controlled by each of the following except phosphor _____
Definition
adhesion
Term
when a phophor is struck by an xray photon, it will emit light
Definition
in all directions
Term
the rare-earth screens use phosphors with atomic #s of
Definition
57 - 71
Term
cassettes should be stored
Definition
empty
Term
When an insufficient quantity of photons strikes the intensifying screen, ___ will appear on the film as graininess.
Definition
Quantum Mottle
Term
Intensifying screens are used to
Definition
-reduce patient dose
-produce light photons
-amplify the incoming xray beam
Term
The protective layer of an intensifying screen is easily damaged by
Definition
fingernails
Term
the normal life of an intensifying screen is ____ years
Definition
5-7
Term
the ability of a material to emit light in response to excitation is:
Definition
luminescence
Term
the precise wavelength of light emitted by the phosphor is termed the
Definition
spectral emission
Term
what % of the latent image is formed by the light photons produced on the intensifying screen?
Definition
99%
Term
an intensifying screen consists of each of the following except the
Definition
lead strips
Term
delayed phosphorescent emission is called
Definition
screen lag and afterglow
Term
the ability of the phosphor to emit as much light per xray photon interaction as possible is a measurement of the
Definition
screen speed
Term
when light emitted from a phosphor is delayed, it is called
Definition
phosphorescence
Term
intensifying screens are typically used with which type of film?
Definition
duplitized
Term
until the 1970s, the most commonly utilized phosphor in radiography was
Definition
calcium tungstate
Term
to increase the speed of an intensifying screen,
Definition
increase phosphor size
Term
which one of the following is not related to resolution?
Definition
base material
Term
the active layer of the intensifying screen is the
Definition
phosphor layer
Term
an important component of the base of an intensifying screen is
Definition
uniform radiolucency
Term
when light is emitted from a phosphor instantaneously, it is called
Definition
flourescence
Term
poor screen/film contact can produce
Definition
lack of detail
Term
the type of interaction that takes place between the x-ray photon and the high-atomic-number phosphor is
Definition
photoelectric and compton
Term
What % of the latent image is formed by x-ray photons?
Definition
1%
Term
Which of the following is NOT one of the layers of radiographic film?
Definition
Reflective Layer
Term
Good characteristics of screen phosphor material include:
Definition
-High atomic #
-Minimal afterglow
-Emits a large amount of visible light when struck by x-ray photons
Term
As speed screen increases, image quality ______
Definition
decreases
Term
As phosphor layer thickness increases, screen speed ______
Definition
increases
Term
Orthochromatic is sensitive to all except for ____
Definition
red
Term
An increase in temperature of an intensifying screen will ______ screen speed
Definition
decrease
Term
T or F: the faster the screen speed, the less radiation required to properly expose the film.
Definition
True
Term
What is the purpose of the sensitivity speck?
Definition
to attract a free silver ion
Term
what is the purpose of adding blue tint:
Definition
reduce eye strain and improve diagnostic accuracy
Term
which types of information are used by computers?
Definition
operating instructions and collected facts
Term
Computed Radiography first became available in
Definition
the 1980s
Term
Computed Radiography detectors can detect information from which source?
Definition
Ionizing radiation
Term
the use of high kVp settings will result in ______ scatter production
Definition
increased
Term
T or F: Changes in tube angle cause foreshortening, never elongation.
Definition
False