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Glossary of Radiographic exposure test 2

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kVp affects ______/_______ of the beam
quality/penetrability
You must select optimum kVp for adequate ________ and thus adequate _______ and ________
penetration; density; contrast
No amount of ___ will compensate for insufficient ___
mAs; kVp
Extremely low mAs->_______ can occur
Quantum mottle
kVp inc->Penetrability ___->Density ___
inc; inc
__% change in kVp yields a visible change in image density
5
__% change in kVp will change image density by a factor of 2 (doubles or halves density)
15
At 70 kVp, a 15% change is about __ kVp
10
To maintain density if you increase kVp by 15%:
Decrease mAs by 50% (1/2 mAs)
To maintain density if you decrease kVp by 15%:
Increase mAs by 100% (double mAs)
Using kVp to maintain density is possible but not desirable because:
Changing kVp also changes contrast and noise
15% rule for kVp and density (formula)
[(kVp2)^4]/[(kVp1)^4] = D2/D1
The ____ the kVp, the less change you need to see a visible difference in density
lower
What would have a greater effect on image density, a 50% change in kVp or a 50% change in mAs?
50% change in kVp
kVp inc->Noise ___
inc
kVp inc->Photoelectric effect ___ and Compton interactions ___->Scatter ___->Fog density ___
dec; inc; inc; inc
kVp inc->Light output from intensifying screen ___->Density ___
inc; inc
kVp inc->Energy of light from intensifying screen ___
stays the same
kVp inc->Contrast ___
dec
High kVp->_____-scale contrast->______ exposure latitude
long; wide
Low kVp->_____-scale contrast->______ exposure latitude
short; narrow
Hand/wrist
54 kVp
Elbow/foot
60-62 kVp
Ankle
64 kVp
Knee
70 kVp
Iodine procedures (IVP, cystogram)
70-76 kVp
Femur
74-76 kVp
Shoulder
74-76 kVp
Sinus
74-76 kVp
Ribs
74-76 kVp
Cervical spine
74-76 kVp
Thoracic spine
74-76 kVp
Pelvis
76-80 kVp
Abdomen
76-80 kVp
Lumbar spine
76-80 kVp
Non-grid chest
80 kVp
Air contrast/barium studies
90-94 kVp
Esophagram
90 kVp
Solid-column barium studies
116-120 kVp
Grid chest
110-120 kVp
Intensifying screen speed inc->Density ___ and contrast ___
inc; inc
film that is particularly sensitive to fluorescent light of x-ray intensifying screens
screen-type x-ray film
type of film that reacts more to radiation than to light
direct exposure film (no-screen film)
Film that is used with intensifying screens reacts more to ______, especially to a certain ________ of _______
light; color; light
What is it called when film reacts to a specific color of light?
spectral matching
The film emulsion is designed to be chemically sensitive to a specific ______ or _______ of light
frequency; wavelength
2 common color-specific films (for a specific intensifying screen)
Blue-sensitive film and green-sensitive film
What type of intensifying screens emit a blue light?
Calcium tungstate
What type of intensifying screens emit a green light?
Rare earth screens
__________ film is sensitive to all colors except red
Orthochromatic
What colors is orthochromatic film sensitive to?
All except red
What is the most common type of film used today?
Orthochromatic film
What color are safety lights?
Red
Orthochromatic film should be used with ________ screens
rare earth
X-ray film consists of an emulsion of ______ _______ crystals suspended in gelatin that is coated on both sides of a transparent blue-tinted polyester ______
silver bromide; base
What is the innermost layer of the film?
Film base
What provides support for the emulsion and also provides a degree of stiffness for handling?
Film base
What is the film base made of?
Polyester material, dyed a blue tint
Why is the film base tinted blue?
To help visualize contrast in the image
What is on both sides of the film base?
Adhesive subcoating
What is the purpose of the adhesive subcoating on both sides of the film base?
To help emulsion adhere to the film base
What occurs when the emulsion is exposed by light from the opposite side intensifying screen?
Crossover
What is the part of the film that contains light-absorbing dye to eliminate crossover?
Crossover control layer
What is the film emulsion made of?
Silver bromide crystals suspended in gelatin
Silver is added to ____ acid to produce _______ ______->Then combined with ________ ______ to form silver bromide crystals
nitric; silver nitrate; potassium bromide
What is it called when emulsion is placed on both sides of the film base, and why is it done?
"Dual-emulsion film;" for a more efficient exposure
How thick is the emulsion layer?
1/1000th of an inch
What is the purpose of the emulsion layer?
To absorb radiation and produce a latent image
An important aspect of the emulsion is its ability to _______ during processing
swell
Why is it important for the film emulsion to swell during processing?
So the processing chemicals can interact with the silver in the emulsion
What color is the gelatin in the emulsion, and why?
Clear/transparent, so no optical impairment of the image occurs (otherwise it would alter the color and contrast of the image)
What is the outermost layer of the film?
Protective coating (tough coat; T-coat; supercoat)
What protects the emulsion layer from scratches?
A thin coat of varnish called the protective coating (T-coat; tough coat; supercoat)
Does the protective coating of the film have to be thin or thick, and why?
Thin, because when the film is processed the protective coating must be removed so chemicals can get to the emulsion
Is mammography film usually single-emulsion or double-emulsion?
Single-emulsion
Film is stored enclosed in what type of bag?
Photo-inert or metal-foil (light tight and air tight)
Radiographic film has to be kept in a cool, dry place. What temperature and humidity level should radiographic film be stored in?
Temp range of 50-70 degrees F. Humidity level of 40-60%
Even though film is stored in a light-tight, air-tight package, it is still exposed to...
natural background radiation and becomes fogged the longer it is stored
Does film have an expiration date?
Yes
Use film by the ________________ principle. Does the older film or newer film get used first?
First In, First Out. Oldest film gets used first
Darkrooms (and other film storage areas) should be lined with...
lead
Where should you handle film to reduce the chance of finger marks and smudges on the film?
As close to the edge as possible
Before handling film, your hands should be...
clean and dry
Name the layers of double-emulsion film in order from one side to the other
Protective coating
Emulsion
Film base
Emulsion
Protective coating



What type of marks can occur when you remove film from a cassette or when you remove film from a box of film?
Static marks
Static marks can occur from rubbing on material such as...
silk, nylon, or rayon
Is static more likely when humidity is low or high?
Low
3 basic types of static
Crown, tree, smudge
Generally, a high speed film is _____ as fast as a medium speed film
twice
Film speed inc->Density ___, contrast slightly ___, and sharpness of detail ___
inc; inc; dec
Why is detail reduced when using a higher speed film?
Because of the increased amount or thickness of the emulsion or larger crystal size
How can film be made more sensitive or "faster"? What is the preferred method for changing film speed?
By increasing crystal size, crystal concentration, or emulsion thickness. Changing emulsion thickness
Is reciprocity law failure more pronounced when using low-speed films or high-speed films?
High-speed films
Films may be designed for a specific scale of contrast. For example, _____ contrast film may be used with a detail/extremity/slow screen
high
How do you determine total system speed?
Multiply film speed by screen speed and divide by 100
the inherent ability of the film emulsion to react to radiation and record a range of densities
film contrast
the inherent ability of the film to record a long range of density levels on the radiograph
film latitude
What will result in higher contrast, exposing film directly to x-rays or exposing film to x-rays in combination with intensifying screens?
Using intensifying screens
High latitude film will produce a _____ scale of contrast (____ contrast)
long; low
Low latitude film will produce a _____ scale of contrast (____ contrast)
short; high
______ image is formed by exposing silver halide crystals
Latent
To contribute to the image, a crystal in the film emulsion must meet 3 requirements:
1-Crystal must contain a sensitivity speck
2-Crystal must be struck with photons of energy (light or x-ray)
3-Crystal must be struck repeatedly with photons of energy to record patient info and contribute to image

What is a sensitivity speck?
An impurity in the crystal that allows the crystal to turn black; development center
Do all crystals have a sensitivity speck?
No. That is why gelatin in emulsion layer is saturated with crystals, so there is a greater probability of crystals with sensitivity specks being exposed
More photons strike crystal->The _______ the crystal becomes
blacker
What does the Gurney-Mott theory relate to?
Latent image formation
Crystal is struck by photon->__ are given off by crystal and then go to the _____________, where they attract ____________
e-; sensitivity speck; positive silver ions
After crystal is struck by x-ray, crystal gives off e-, e- go to sensitivity speck, and e- attract positive silver ions, the crystal is considered ______
broken
After crystal is broken, chemicals can...
react with crystal and make it turn black
Is a silver bromide crystal more sensitive to light/x-ray before or after it is broken?
After it is broken
Is film more sensitive to light/x-ray before or after it is exposed?
After
What is the processing room also called?
Darkroom
What is the light-tight area where films can be inserted into and removed from cassettes?
Darkroom (processing room)
What type of processor is cheap and used in smaller places?
Desktop processor
After you place film into a desktop processor...
you can turn on the light or open the door because the inside of the processor is light-tight
What is another name for a multiloader?
Daylight processor
Multiloader (daylight processor) is similar to...
a CR reader
Multiloaders are manufactured to be used with one specific type of ______
cassette
Darkroom must be well _________ because of chemicals. Optimal _____ and _______ ranges must also be maintained
ventilated; temp; humidity
Where is film kept?
Film bin
What is the box that opens from the outside of the darkroom to the inside?
Pass box
Can both sides of the pass box be open at the same time?
No
Are safelights 100% safe?
No; eventually safelights can fog film
An exposed film is __x more sensitive to safelight than unexposed film
8
What type of safelights should be used, if possible?
Indirect
How are safelights named? What are 2 names of safelights?
By name of safelight filter. Kodak GBX and Wratten 6B
Development of film changes silver bromide crystals into...
black metallic silver
What part of processing removes unexposed and undeveloped silver bromide from the emulsion?
Fixing process
What part of processing hardens the soft gelatin emulsion containing the metallic silver image?
Fixing process
What part of processing removes the fixing bath and silver salts from the film emulsion, and what does it use for removal?
Washing process; water
The transport system moves the film through different _____ in the processor
tanks
What turns the silver crystals black?
Chemicals in the developer
What is the solvent in the developer and fixer?
Water
Chemical reactions require that the chemicals...
be dissolved in water
the actual chemical that turns the exposed silver into black metallic silver
reducer
chemical that reduces silver bromide crystals to black metallic silver
reducer
What are the 2 types of reducers?
Hydroquinone and phenidone
Which reducer is responsible for the gray tones in the image?
Phenidone
Which reducer is responsible for the black tones in the image?
Hydroquinone
What softens the emulsion so reducers can interact with silver?
Activator
What acts as an alkaline catalyst for reducers?
Activator
What chemicals are included in the developer tank?
-Solvent
-Reducer
-Activator
-Preservative
-Restrainer
-Hardener




What chemicals are found in the fixer tank?
-Solvent
-Acidifier
-Clearing agent
-Hardener
-Preservative



What chemicals are found in both the developer tank and in the fixer tank?
Solvent, preservative, and hardener
What controls the activity of the reducing agents?
Preservative
What helps control oxidation?
Preservative
What maintains the life of the solutions in the developer tank and in the fixer tank?
Preservative
When solutions in the developer or fixer tanks are exposed to oxygen, the life of the solution is...
shortened
Developer solution is _______ as it ______ the film emulsion
oxidized; reduces
What limits the reducers to reacting with only those crystals that have been exposed?
Restrainer
What checks the action of the reducers and prevents over-development fog?
Restrainer
What limits the amount of softening of the emulsion caused by the activator?
Hardener
What neutralizes remaining developer solution in the emulsion?
Acidifier
What acts as an acid catalyst for clearing and hardening agents?
Acidifier
What changes the underexposed or unexposed/undeveloped crystals into silver salts that are removed from the emulsion?
Clearing agent
What removes unexposed silver bromide crystals from the emulsion?
Clearing agent
What restrains the swelling of the emulsion and completely hardens it so film can be handled?
Hardener
What shrinks and hardens emulsion for extended durability?
Hardener
What assists in clearing film and also helps prevent oxidation in the fixer?
Preservative
What are some processing variables?
Time, temp, and solution in developer; time, temp, and solution in fixer
Time in developer inc->Image density ___
inc
Temp in developer inc->Density ___
inc
If developer solution is weak or old, will film be underdeveloped (light) or overdeveloped (dark)?
Underdeveloped
If fixer solution is in the developer, will film be underdeveloped (light) or overdeveloped (dark)?
Underdeveloped
If developer solution is very strong or concentrated, will film be underdeveloped (light) or overdeveloped (dark)?
Overdeveloped because of chemical fog
Increasing development time, temp, or concentration increases image _____ and also image ______ (up to a certain point, past which excessive development time will turn the entire film black and destroy contrast)
density; contrast
Increasing development _____, ______, or ________ increases image density and image contrast up to a point
time, temp, concentration
Excessive time in fixer->Film will be too _____ and may become _____ and crack
hard; brittle
Fixer temp inc->Speed of fixation ___
inc
If fixer solution is old, weak, or insufficient, film will come out...
sticky and wet
If fixer solution is underconcentrated, film will come out...
sticky and wet
If fixer solution is too concentrated, film will come out...
overhardened
Insufficient fixation time, temp, and concentration can result in...
emulsion damage and discoloration
Excessive fixation time, temp, or concentration makes film...
brittle
Does film processing affect geometrical factors of the image?
No, just photographic (visibility) functions
Automatic processors allow more ________ results to be obtained in much ____ time
consistent; less
What type of processors greatly reduce time for film development?
Automatic processors
What tanks are included in an automatic processor?
Developer, fixer, washer, and dryer compartment
How long does it take an automatic processor to develop a film?
1-4 min (many take 90 sec)
Systems within the automatic processor
Transport, electrical, recirculation, replenishment, temperature control, silver reclamation
How should you place film in the feed tray of the processor?
Crosswise
Orientation of the film in the feed tray controls how much ________ is going to occur
replenishment
After film is completely inside processor, a ______ goes off and then you can...
buzzer; open door of darkroom
What is placed over the tanks in the processor to help prevent oxidation?
Dust covers
What is the first set of rollers the film comes into contact with?
Detection rack (feed rack)
When film passes through the rollers of the ___________, the rollers are pushed apart which activates a microswitch that turns on ____________
detection rack (feed rack); replenishment
Replenishment system pumps fresh replenisher solution into both _______ and _____ tanks
developer; fixer
When does replenishment stop?
After film has passed through rollers and rollers come back together, turning off the microswitch
What is at the top of the detection rack (feed rack) to direct the film down into the developer tank?
Guide shoes
Whenever film must turn in the processor, ______ are there to direct the film
guide shoes
What transports film up and down through the tanks?
Planetary rollers
What is the large roller at the bottom where the film turns back up?
Solar roller
What squeezes most of the solution off the film before it reaches the next tank in the processor?
Squeegee rollers
After squeegee rollers, what is located at the top of each tank?
Crossover rack
What is crossover rack made of?
Roller and 2 guide shoes
What is found in the dryer rack?
Rollers alternated with air tubes
What part of the automatic processor provides power to operate the motors, pumps, blowers, and heaters?
Electrical system
What part of the automatic processor has a dedicated pump and tubing lines that carry the tank solutions through a heat exchanger and back into the tanks?
Circulation system
What does the heat exchanger in the circulation system do?
Maintains temp, since it is best to keep the solutions at a certain temp
Recirculation lines of the developer solution have a special ________ to prevent debris from accumulating in the developer tank
filter
What will happen if dirt and debris accumulate in the developer tank?
Every time a film goes through the developer, dirt and debris on the rollers will stick to the film
As film goes through the automatic processor and uses up solution, the __________ puts new solution in the tank
replenishment system
What is the visual indicator that replenishment is taking place?
Replenishment indicator (black balls)
For one 14x17 CW film, the replenishment rate for the developer is _____ ccs and the replenishment rate for the fixer is _____ ccs
60-70; 110-120
Where are the replenishment tanks?
External to the processor
A float is on top of the developer solution to prevent...
oxidation
The water tank must also be replenished, since it uses about ____ gallons per minute. The water must also be mixed up or it will become...
1-3; stagnant and develop algae
The temperature gauge is on the front of the processor to tell the temperature of the ________. There may also be a temperature gauge for the _______
developer; dryer
Normal temp in processor is usually between ____ degrees Fahrenheit
92-96
Anything that heats up solution in the processor is part of the _______________ and is used to maintain a constant temperature for the solution
temperature control system
Why do we save the silver that is washed off the film?
-Worldwide supply of silver is dwindling
-Silver can be sold since it has monetary value
-Some states have laws that say you must save silver

Film that has been totally exposed is called _____ film, and it has ____ of the silver available to recover
black; some
Film that has been partially exposed is called _____ film, and it has ____ of the silver available to recover
exposed; some
Which has the most silver available to recover: green, clear, black, or exposed film?
Green
Where is the silver reclamation system?
Attached to processor
3 approaches to recovering silver from processor
-Metallic replacement
-Electrolysis
-Chemical precipitation

In ____________, the solution goes through a canister that contains iron. Silver in the solution reacts with iron and remains in the tank
metallic replacement
In _________, solution passes through a canister with an electric current. Silver attaches to cathode
electrolysis
In _____________, chemicals are mixed with the silver solution. A chemical reaction occurs and the silver drops to the bottom of the tank. The remaining solution is washed out of the tank
chemical precipitation
When a film is scratched, it appears like...
little white lines on film because of the emulsion that has been removed
Guide shoe marks appear like...
vertical white lines on film
What are the artifacts that occur because of dirt/debris on the planetary roller?
Pi lines (since they appear at 3.14" apart on the film)
the measurement of the response of x-ray film (emulsion) to exposure and processing
sensitometry
the quantitative measurement of film response to exposure and processing conditions
sensitometry
We measure sensitometric properties with...
a characteristic curve (H&D curve)
What is H&D?
Hurter and Driffield
H&D curve is a graph produced by exposing a film and plotting various _____ levels against the logarithm of ________ that produced them
density; exposures
2 different ways to make an H&D curve:
-Expose a regular film with a step wedge
-Expose a film with a sensitometer
Which is preferred for sensitometry, a sensitometer or a step wedge? Why?
Sensitometer. Sensitometer creates a uniform exposure each time you expose the film
What is D-min (minimum density) for an H&D curve?
Toe (bottom curve of graph)
The toe would represent the _________ part of the step wedge or the ______ step of the sensitometer
thickest; lightest
What is the slope of an H&D curve, and what does it represent?
The body or straight line portion. The slope represents film contrast
What is D-max (maximum density) on an H&D curve?
Shoulder (at top curve of graph)
The shoulder would represent the _________ part of the step wedge or the ______ step of the sensitometer
thinnest; darkest
Will the densitometer reading (optical density) of a film ever be zero?
No. The blue tint of the base and background radiation add density to the film
Where does base+fog density come from?
The blue tint of the film base and the background radiation
What are normal base+fog values?
0.18-0.22
Base+fog should never exceed...
0.25 (since the useful range of densities is 0.25-2.5)
What is the primary value of the H&D curve?
To compare different types of films or different processing conditions
the relative exposure required to produce a density of 1.0 + base+fog
film speed
The less exposure required to produce density on the film, the _____ the film
faster
On a graph of H&D curves, is the film furthest to the right or the film furthest to the left faster?
Left
the point where 1.0 + base+fog will interact with the H&D curve
speed point
On a graph of H&D curves, whichever film has a speed point furthest to the ______ is faster
left
Contrast formula
Contrast = (OD2-OD1)/(LRE2-LRE1)
-OD2 represents optical density of 2.0 + base+fog
-OD1 represents optical density of 0.25 + base+fog
-LRE is log relative exposure


The contrast of a line at a __ degree angle will always be 1
45
The contrast of a line at a 45 degree angle is always...
1
If the slope is steeper than 45 degrees, the contrast will be ____ than 1 (_____ contrast)
more; high
If the slope is less steep than 45 degrees, the contrast will be ____ than 1 (_____ contrast)
less; low
contrast that is measured between 2 points on the H&D curve (1 point being 0.25 + base+fog; the other point being 2.0 + base+fog)
average gradient
exposure range over which the IR responds with diagnostically useful optical density
film latitude
If H&D curve has a steep slope, film latitude is ______
wider
IGNORE CARD BEFORE THIS ONE! If H&D curve has a steep slope, film latitude is...
narrower
If H&D curve has a less steep slope, film latitude is...
wider
You must use _________ to create processor control charts
sensitometry
To compare different processing conditions, you must have a...
processor control chart
The processor control chart is a...
quality control method
4 components of a processor control chart
-Speed
-Contrast
-Fog
-Temperature (is also recommended)


To make a processor control chart, you should record speed, contrast, fog, and temp at the same time on a _______ basis for at least ______
daily; 1 week

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