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The Best of the Best Presentations list 2011

"Trash Talk Humor"

 "Pictures Never Seen Before-NEVER FORGET"-911

"Déjà Vu ©"

Love for all time-(When Your Hot ©)

Amazing Drug Lord  Photos and Story

The Muddied Shoes Blues ©

The Best of the Best Presentations list 2010

American Rising

The Patriotic War

Strangers on my Flight

Fauna music and love

Ancient Hanging Monastery

What Tiger should have seen first!

Another Senior moment in Police Science History

Patriots in action

US Marine Corps Answering Machine

Best Train vs. Tornado

Bud Light Clothing Drive Commercial Banned from the Super Bowl

Who packs your parachute?


Frank the Duck

Obama Man Can.

B-17 fighter pilots in World War II

Worlds Most Expensive Catastrophes

Worlds largest spectacular entities

Enjoy fabulous and spectacular 3D Trick of the Eye Murals

View the largest and most terrifying holes in our Universe.

911Aerial Surveillance Photos

View this amazing town with their more amazing road sign

A330 Air France photo with passengers being sucked out of the gaping hole in the plane

Homeland Security Warnings.

"When its was not your time to die"

Your homeland security at work for you

Are you safer in a 1959 Chevy or 2009 Chevy

Barry the Fishermen

Airplane Disasters with Airline Humor

The Family Grizzly knows but did you know?

Advice for InfoJustice Readers


State the level of exposure where there is no genetic or somatic damage. 0
Once a pregnancy becomes known, radiation dose of the embryo-fetus shall be no greater than___? 0.05 rem (50 mrems) in any month or knowing 0.5 rem at time of pregnancy, she shall not exceed .05 rem during the remainder of the pregnancy.
What is the whole body non-occupational exposure allowed for the general public in an unrestricted area? 0.1 rem per year, 1.0mSv/year, 0.002 rem/hr or 2mrem hr (continuous or frequent exposure)
High radiation area for the public can not get ___? >0.1 rem/hr at 30 cm distance from the source.
When under 18, the max permissible dose is___of the adult? 1/10
For shielding purposes, the maximum permissible exposure for controlled area is? 0.1 R/week
What is the average energy of an X-ray beam produced at 80 kVp? (1/3)*80 = 26.67 kVp
The maximum allowable yearly dose to the general population is? 0.5 rem/year (Technician 5 rem/year) for infrequent exposure.
Lead apron should be no less than___? 0.25 mm lead equivalent
Out of total filtration required, how much is considered? 0.5 mm (X-ray tube) add 1 mm A and mirror=1 =2.5 mm total=Inherent + added
Total filtration is? 0.5 mm inherent, 2 mm aluminum equiv = 2.5mm equiv
Gonad shield should be no less than___? 0.5 mm lead equivalent
State the MPD for the general public per year 0.5 REM
State the MPD for pregnant occupational workers exposure? 0.5 REM per gestational period
In terms of REM, what is the quality factor of x-rays and gamma rays? 1
What two things must pregnant workers do in regards to taking x-rays?
1. They do not take x-rays.  2. Get a new radiation badge - fetal badge
100 Rem = ______Sievert. 1Sv
100 Rad = _____Gray 1Gy = 1 joule/kg. 
How much of the electric and kinetic energy of the projectile electrons are converted to x-ray? 1%
___ mRem = 1 Rem 1,000
In x-ray: ____R = _____Rad = _____Rem 1,1,1
X-rays are produced by two methods.  Please name them? 1. Bremstrahlung (braking) radiation - polychromatic and 2. Characteristic radiation which is monochromatic. (All X-rays are a combination of the two).
Percentage for repeat films associated with a foreign object? 2%
Out of total filtration required, how much added by manufacturer? 2mm A1 equivalent
What is the average number of films per examination? 2.2
The amount of aluminum filtration recommended for diagnostic x-ray tube operating above 70 kVp should be at least? 2.5 mm including the inherent filter
What is the average exposure per year in the USA?
A cervical spine radiograph requires 12 mAs at 72" SID. What mAs is required to achieve the same radiographic density if the SID is changed to 40"? 3.7 mAs
How far should the safe light be from the work station? 4 feet
Developer temp. is 72º, how long do you develop? 4 min.
What is the old cumulative life time exposure formula? (5n-18) where n = age
Time and Temperature of manual developer processing? 5 minutes at 68°F
For maximum speed and contrast, films in a 68 F developer should be developed for? 5 minutes (Manuel Processor) Developer.  Fixer time is 10 minutes and Wash time is 20 minutes.  5, 10, 20.
What is the occupational (MPD) whole body exposure dose (Tech)? 5 REM/year (Technition) or 0.05 Sv = 50mSv
State MPD for pregnant occupational exposure? 5 Rem per gestation period (9mo.)
What is the dose limit for a fetus? 5mSv
What is the skin entrance radiation dose for the Chest 400 speed? 5-15 mrad
J\1PD for pregnant employee? 5 REM per gestation period
State annual MPD for your friendly neighborhood Radiology Tech? 5 Rem/year
Annual Whole body MPD for occup. exposed people? 5REM
Percentage for repeat films associated with processing errors? 6%
What percentage of X-rays are taken in Medical Groups? 7%
An upper GI exam is performed at 3 mA for 2 minutes.  What is the total exposure if the patient's exposure rate is 1.2 R/mA/minute? 7.2
With upper cervical tech, what is recommended grid ratio 8:1
What is the skin entrance radiation dose for the extremity (elbow, shoulder...)? 8-30 mrad
Upper cervical practitioner should purchase what grid ratio? 8:1
The exposure rate 3 feet from a source of radiation is 40mR per hour. What is the exposure rate at 6 feet?  10

When do you use grids?

>10cm patient parts
If a technique is based on 200 speed imaging system and requires 30 mAs, 80 kVp, 40" SID, what must be done to compensate if a new 600-speed system is used? 10 mAs
Level of fetal exposure below which no abortion is recommended? 10 RAD
Regular full spine (14 x 17), what is grid ratio? 10:1
What size grid is appropriate for 14x17 films? 10:1
When is it necessary to use a grid? > 10 cm Thickness and > 60kVp
Percentage for repeat films associated with patient motion? 11%
Full spine x-rays are taken with what grid ratio of? 12:1
What size grid is appropriate for 14 x 36 films? 12:1 or 16:1
What is the maximum Watts for a safe light? 15 Watts
What is the annual permissible dose for the Eye? 15 rem
State the maximum safe light voltage? 15 Watts
How much must the kv change to double radiographic density? 15%
If you decrease your exposure time by 1/2 you can increase your kVP by_______ and still obtain the same overall film density? 15%
For RAO projection of the neck the central ray has? 15 degrees caudal tilt. (RPO-15 up)
What procedure is used to perform a AP view of the sacrum? 15 degree cephalad tube tilt
Maximum allowable dose for the lens of the eye? <15 rem/year or 0.15 Sv/y
What is the percentage of extremity X-rays? 17%
What percentage of X-rays are taken in Private Practice? 18%
20 mRad of x-ray exposure = ____mRem . 20
If 5 MAS is required at 40 SID what MAS do you need at 80 SID? 20 MAS
Percentage for repeat films associated with poor positioning? 25%
What is the percentage of lumbar/abdominal X-rays? 25%
Acute dose temporary infertility in males? >30 rads.
This amount of change in this factor is required to see change in radiographic density? 30%
X-rays produced during diagnostic radiography have energies of approximately what?
40KeV to 120KeV
Proper range of humidity for film storage? 40 - 60%
Embryological effect for absorbed abortion? 50 rad asorbed=>abortion
What is the annual permissible dose for the skin & extremities? 50 REM/year or 0.5 Sv/year
J\1PD for any extremity? 50 REM/year
What is the optimum KVP for extremities under 10cm of thickness? 50 to 60 if non bucky
What percentage of X-rays taken are of the chest? 50%-25% lumbar/abdomen, 17% extremities, 9% neck with 2.2 films/exam.
Percentage of repeat films  with exposure calculation error? 50%
Operating portable x-ray equipment requires ___between technologist and patient, x-ray tube and useful beam? 6 ft.
Range of temperature manual processing limited to? 60 - 75 degrees (Automatic processing 92-95 degrees).
The maximum lifetime accumulated exposure for a technician 30 years old is? 60 rems (30-18=12, 5 (5 rem/year) x 12=60 rems)
What percentage of all X-rays are taken in a Hospital setting? 64% -  7% in med group, 19% in private practice and 10% other.
What % Attenuation is expected of 75kVp primary beam by a lead apron of 0.25 mm lead, .5 mm gonadal shield and 1.0 lead block? 66.0%, 88% and 99.99%
At least _____ kVp is required to produce useful energy K-
characteristic  X-rays of tungsten?
What is the optimum KVP for spine imaging? 70 to 90
Which FFD should the Chest, AP full spine and Neutral lateral cervical be taken at? 72 FFD
X-ray taken at 100mAs at 90kVp can be changed to 200mAs___and still maintain the same radiographic density? 72 kVP (90 x .2=180, 90-18=72)
How much of radiographic image is produced by intensifying screen? 95%
About___% of recorded density (blackening) on the film exposed with intensifying screen is photographic in origin? 98%
How much of the electric and kinetic energy of the projectile electrons are converted to heat? 99%
In an x-ray tube, fast moving electrons collide with matter to produce x-rays. When the electrons interact with the atoms of the target what are two ways that the energy is given off?
99% given off as heat, 1% able to give up their energy in one step that produces a photon
1 rad = 0.01 Gy = ? 100 ergs/gm (100 rad = 1Gray=1 joule/kg)
State the average annual exposure that medical personnel receive. < 100 mREM
Diagnostic X-ray tube housing must be sufficiently shielded to limit exposure one meter from housing to____? 100 mR/hr or .1 R/hr
How many REM = 1 Sievert? 100
Difference of exposure between controlled/uncontrolled area 100 mr/ 10 mr per week allowable exposure
1 Gray (1Gy) = 100 rad
1 Sievert (1Sv) = 100 rem
Which imaging system would result in the most radiation exposure to the patient? 100 speed
Which imaging system would you choose if you were imaging extremities? 100 speed
Cataractogenic effect occurs at? Several hundred rads
A lumbar spine radiograph requires 30 mAs at 40" SID.  What mAs will be required to achieve the same radiographic density if the SID is changed to 80"? 120 mAs
What is the skin entrance radiation dose for an AP and Lateral Cervical spine? AP=95 mrad with the lateral 125 mrad.
What is the skin entrance radiation dose for the thoracic spine? 200 mrad
What is the skin entrance radiation dose for the abdomen? 300 mrad
What is the acute dose for female infertility? >300 rad=>infertility in female (again >30 rad=>temporary infertility in male).
Define isotropic? 360 degree emission of light or 360 degrees divergence of x-rays and other types of light
What is the lowest film-screen system speed that you should consider using for routine spinal radiographs? 400 speed
The lowest dose given in a single exposure to permanently sterilize a male is: 500 rads
The lowest dose given in a single exposure to permanently sterilize a female is? 1000 rads
Which imaging system would result in a radiograph with the most quantum mottle? 1200 speed
Which imaging system would result in the least radiation exposure to the patient? 1200 speed
Which imaging system is the most consistent with the ALARA concept? 1200 speed
State the annual whole body MPD for occupationally exposed persons in mRem. 5,000 mRem
What device is used to test for film screen contact? A copper screen, wire mesh
To maintain the same radiographic density, increase of 10 kVp for an exam operating in the 70kVp range can be compensated by? A reduction of exposure time by 50% (Cut time in 1/2).
How does a grid work? A thin sheet of metal (lead) has a high atomic number and it absorbs protons and electrons.
Explain effects of using oxidized developer on Non-Threshold Effect? a) Density is b) Contrast is ↓. (Gets Whiter)
What are the three things that can happen to an x-ray photon? Absorbed, scattered, no interaction (pass through)
Why is the back of the room lined with lead? Absorb back scatter
Why is the back of the cassette lined with lead? Absorb backscatter
Sodium carbonate to soften and swell the emulsion so that the reducers can reach exposed grains is the function of? Activator during the Developing stage.
Name a practice that is not advisable? Advertise free x-ray exams during health fairs.
Compare the cost of Full Wave Rectification to High Frequency Rectification. Add $3000
If a lumbar spine x-ray was accidentally taken during her first term of pregnancy, what should the doctor do? Advise the patient not to take unnecessary x-rays anymore.
What is the current cumulative life time exposure formula? Age times 1
Yellowish and brownish discoloration suggests? Aged fixer.
Method of reducing scatter Radiation but ↑'s magnification? Air Gap Technique
What are the 5 radiographic opacities from most radiolucent to the most radiopaque?
Air, fat, soft tissue (fluid), mineral (bone), and metal
As low as reasonably achievable? ALARA
This radiation can be stopped by a piece of paper, what kind is it? Alpha
What has the highest specific x-ray ionization? Alpha particle
How is film manufactured to increase its' speed? Amount of crystals, size and shape
Coherant Scattering photon interacts with? All electrons of the atom - found in diagnostic x-ray
What is the measure of current flow?
Ampere - since current flow is small milliampere mA
The ____ side of the x-ray tube emits x-rays that are relatively perpendicular to the film. Anode
What is the Anode heel effect? An x-ray beam is not uniform as it exits anode. There is decreased intensity on anode side of tube. The energy increases toward the cathode side. The right side of the tube is typically the cathode
How should you have your tube installed? (Which side up?) Anode
Which side of the radiograph will be the sharpest? Anode
Describe the use of "split screens" Anode --> Thin part of the body

Cathode --> Thick part of the body
That the Cathode side of the tube has more radiation intensity (104%) and the Anode side has less radiation intensity distribution (of only 97%) is called___? Anode Heel effect
What are the associated charges with an anode and cathode?
Anode (+), cathode (-)
Where is the anode during an Lateral Thoracic Anode down
Where is the anode during AP Thoracic Anode up
Name one view which has a caudal tilt of the x-ray tube? AP coccyx
Controlled area: Area where x-rays are taken
Crossover exposure related to detail: As crossover increases, detail decreases
Define ALARA As low as reasonably achievable
Developer begins to age? As soon as it is mixed.
How does collimation to the film size or smaller effect the production of scatter radiation? As the collimated field size decreases, compton scatter interactions also decrease (less atom at the path of travel).
If the film is severely underexposed how do you fix it? At least double mAs
What is PBL? Auto collimation - positive beam limitation
Automatic vs. manual processing chemical difference: Auto has hardener
Selects the kVp? Autotransformer
Increasing time and temperature in the developer solution will increase? Average gradient, film contrast and increased fog.
Describe how developer should be mixed. Avoid over oxygenating the liquid. Run it down the side of the tank to minimize oxidation.
Control badge monitors: Background and transport radiation
Comparing annual radiation exposure to the population in the U.S., most exposure comes from this source? Background: cosmic, terrestrial
Which environments have the highest background radiation? Beach area and high mountain areas.
What are the two methods to control scatter? Beam restriction or collimation and grids
Why is there a floating lid on the developer replenisher chemistry? Because as the developer ages the oxidized developer tends to rise to  the underbelly of the rust color and then settle back down to the bottom of the container contaminating the liquid
Why is a free electron in human tissue a worry? Because they are highly reactive and believed to be involved in degenerative diseases and cancers.
A small focal spot produces? Better details.
Improper grid radius results in this pattern of grid cutoff? Bilateral
Developer converts silver halide crystals to? Black metallic silver
The developer converts exposed silver crystal halide to? Black metallic silver
The visible image of the radiograph is composed of? Black metallic silver grains.
Dark room should not be painted this color? Black. Dark Rooms needs color to reflect safe light.
What color of light do calcium tungstate screens emit?  What type film must be used with them? Blue-violet. Blue sensitive film
This occurs if screen-film contact is poor? BLUR! (geometric).  Remember Fog is a photographic issue.
What 5 things is each technique chart specific for?
Body region, cassette/screen type (speed), grid vs. table top, x-ray unit, FFD
What type of tissue is most likely to undergo photoelectric absorption? Bone Enamel
When improper SID is used on a grid, what does grid cut off look like? Both lateral side of the film are cut off an underexposed
Improper SID used on focus grid; Pattern of grid cutoff looks like? Both sides are cutoff; so the film is underexposed
Improper grid radius results in this kind of cut off? Both sides are underexposed.
What are the two ways that diagnostic x-rays are produced?
Bremsstrahlung radiation "breaking radiation" and characteristic radiation.
This x-ray production process produces the majority of x-rays in the beam? Bremsstrahlung
What is the predominant mode of radiography? Bremsstrahlung radiation
Occurs when an electron penetrates the anode metal and passes close to the nucleus of the tungsten atom where it is deflected and slowed down by the attractive forces of the nucleus? Bremsstrahlung radiation
Occurs when an electron is slowed down due to a nuclear force field? Bremsstrahlung
When projectile electron is slowed by nuclear force field, these x-rays are called? Bremsstrahlung
Intensifying screens are made up of? Calcium tungstate.
What causes a dark band on the long edge of a film? Cassette hinge is defective or cassette cover not tightly closed.
Shadows of cassette hinges along one side will show up on the film only when? Cassettes are inserted into the cassette tray backside toward the front.
Give a disease example of RAD reduced response that follows threshold response? Cataracts
This side of the radiograph will exhibit the most blur? Cathode
This side of the tube produces the most xrays? Cathode
X-rays travel from _______ to _______ to make x-rays Cathode to anode
Electrons travel from: Cathode to anode to make x-rays
What is the cause of quantum mottle?  What does it look like? Caused by too few x-rays, low mAs/fast speed film.  Quantum mottle is the proper name for film graininess.
What does a rectifier do? Changes AC current to DC current
Which of these methods produces X-rays when electrons shift energy levels/shells within the atom? Characteristic Radiation

Occurs when the incoming electron strikes an orbital electron and ejects it from its shell?

Characteristic Radiation
What relationship between exposure and density is plotted on a curve called? Characteristic curve
What view would be benefited from short exposure time? Chest film (Careful not to see motion artifact/blur film-hold breath)
Full inhalation is used in which view? Chest view.
Which type of examinations utilize longer FFD or SID? Chest and, lateral cervical .
Coherent Scatters is also known as? Classical Scattering or unmodified scattering.
Two purposes of fixing? Clear off undeveloped silver halide and harden film
Ammonium or sodium thiosulfate is used to remove underdeveloped silver halide grains from the film.  The unexposed grains leave the film and dissolve in the fixer.  This is called? Clearing  (The clearing activity can recover the accumulated silver and then electroplate it onto a metallic surface within the silver recovery unit).
Which x-ray interaction is the most likely to occur at energies below 10 KeV? Coherent Scatter
Thompson (photon interacts with a single electron) & Rayleigh are? Coherent Scattering types.
Film Fog can be caused by? Coherent Scatter
Oxidized developer looks like? Coke or used motor oil
Where does a pregnant women wear film badge (s)? Collar and waist over lead apron
Name two things that can reduce Compton backscatter Collimating and lead in the back of the cassette
2 devices used to reduce Compton scatter: Collimation and bucky or compression band
Define Total Filtration Combination of added which is equivalent to 2 mm of Al and inherent which is .5 mm from the Pyrex tube itself therefore giving you 2.5 mm of Al equivalent.
Besides using the anode heel effect properly there are two other options that may help to produce a more uniform film density. They include? Compensating Filters and Slow Speed where area is thin; faster speed where is thickest.
What are the two types of digital imaging?
Computed radiography and digital radiography
A partial transfer of energy upon collision is characterized by the? Compton effect.
Which x-ray interaction with matter is related to the energy of the x-ray photon? Compton - increasing energy, increases the probability of it occurring.  It is totally independent of atomic number of the material it is interacting with. 

Photoelectric - decreasing KVP increases the probability of it occurring.

Classical - decreasing energy will lead to increase in probability.
Which interactions with matter discussed are important in diagnostic level radiography? Compton Effect and Photoelectric Effect
Name of X-ray reaction with matter and Fog? Compton Scatter
Which x-ray interaction with matter is most likely to occur at energies greater than 60 keV? Compton Scatter
How does kVp effect the production of scatter radiation? Compton scatter interaction increases as kVp increases.  The ideal is no scatter as Scatter leads to poor contrast, fog, and dull film.  Increasing kVp will give long scale of contrast and thus lots of shades of gray.
Thermionic emission or 99% of the energy are converted to heat and dissipated by a rotation anode made of? Copper
What is the anode made of and why? Copper with tungsten target. Copper because it's a good heat conductor and anode is covered by tungsten because it as a high atomic number and a high melting point.
Why does the path the x-ray travel matter? Concentration of chemistry
The focusing cup is to? Concentrate the electron stream toward the anode.
Differential absorption results in this photographic property? Contrast
What are three examples of natural radiation?
Cosmic rays (sun), terrestrial (uranium, radon, thorium) and internally deposited radionucliotides.
Inside a cassette cabinet is? Counter weight balance.
Why is density expressed in logarithm? To conveniently express large differences in small numbers.
What is the function of the developer? Converting silver halide crystals to black metallic silver.
What does a rectifier do? Converts AC to DC current
State the unit that a physicist would use to describe ionizations in air in Systems?  International nomenclature. Coulombs/kg
What is the measurement of radiation exposure in air?
Coulombs (used to be Roentgen)
Why do we leave the developer lid open at night? Cross contamination of fixer and developer due to condensation
Why does a double-coated film emulsion result in a decrease in sharpness? Cross over
What chemical can replace sodium sulfite as a preservative in automatic processing? Cycon
Crescent or moon shaped areas on an x-ray film is caused by? Bending the film before exposure.
What type of current is required to produce x-rays? DC
How do you Q. Mottel? system speed ( film screen speed) Or... Use higher MAS
Effect of reflective layer on sharpness? Decrease
Purpose of intensifying screens? Decrease patient exposure and extend tube life?
What are the two purposes of collimation? Decrease patient dose of radiation and decrease scatter (thus improve radiographic quality)
Describe the effect of oxidizing developer has on the density of films. Decrease density so films get lighter.
If a tube overload occurs? Decrease mA, increase time
What is the purpose of intensifying screens? Decrease patient exposure
What is the purpose of the air gap technique? Decrease scatter
As TFD increases what happens to blur? Decrease TFD = SID
With tube overload, what must be set? ↓mA ↑time
What is the advantage of a high frequency grid? Decreased line visibility and no need for a moving grid mechanism.
As FFD, TFD, & SID Increases blur does what? Decreases
How can you decrease the heel effect? Decreases with small field size and increased film-focal spot distance
An increase of 10 kVp can be compensated by? Decreasing the exposure time by 1/2 (↑ 10 kvp 1/2 mass)
Poor screen film contact results in? Definition reduction.
Effect of using oxidized developer on density and contrast? Density decreases and contrast decrease
Effect of using a higher than appropriate developing temperature on both density and contrast? Density increases, contrast decreases
Males receiving radiation for ankylosis spondylolisthesis: Develop leukemia
Which type of x-ray equipment requires no cassette/image storage device? DR digital x-ray unit.
What is the processing order to "fix" a film? Fixer, Acidifier/activator (Acetic Acid), Clearing agent (Ammonium thiosulfate), Hardener (Potassium alum), and Preservative (Sodium sulfite)
List the times for the various processes in a 90 second Automatic Processor beginning with the Developer? Dev-20-25 sec, Fixer-20 sec, Wash-20 sec, Dry-25-30 seconds.
This processing solution is alkaline? Developer
What are Hydroquinone and Elon?  What is their function? Developer.  Act as reducing agent.
Where is the hardener in auto developer? Developer and Fixer
Which chemical prevents rapid oxidation of the developer? Sodium sulfite (Preservative).
The function of the preservative is to? Prolong life of developer.
What is radiographic contrast? Differential absorption of tissues; Results in different degrees of white and black on the film.
Replenishment rates in automatic processing are dependent on this? Direction of film travel thru film processor
How is the grid ratio related to patient exposure? Directly
Density SID Equation Directly Proportional (old/new = old2/new2)
Kvp and compton scatter: Directly related
Scratch marks of the films are usually caused by? Dirty rollers.
This type of grid has strips that converge with angle of ray? Divergence
Stochastic effect? Does not have a threshold
Reproducibility: Doing the exact same exposure over and over and getting the exact same results
What are advantages to have a  \high grid frequency? Don't need moving grid and no lines on the film
When you need to double the density, what do you do to mAs? Double mAs
An increase in the log exposure to the film of 0.3 always increases film density by? Doubling
Where should the anode side of the tube be placed when performing a lateral thoracic spine radiograph? Down
Which edge of the processor feed tray should be used and why? Either the top or bottom edge. To insure that the chemistry is evenly distributed over the entire film and to allow for the entire radiograph to be developed.
What is an X-ray? Electromagnetic Energy
What is an X-ray and elaborate? Electromagnetic energy is the transport of energy through space as a combination of electric and magnetic fields.  X-Ray wavelength is measure in billionths of an inch, thus has high frequency and reacts with atoms
What is another name for a single x-ray in the beam? Electromagnetic Radiations; Proton
Radio waves, microwaves, ultraviolet, infrared, and visible light are? Electromagnetic Radiation.
Electrical energy in the x-ray system is used to produce what? Electromagnetic energy which is converted to chemical energy in the radiographic film or detector.
In the x-ray tube, how are the x-rays produced? Electrons are boiled off from cathode to anode/
Describe how and when crossover rollers should be cleaned. Every day.  Pull up the developer (rubber) and fixer (wood) rollers and using a plain old sponge to clean them. Have one color spong for the developer and one for the fixer.
TLD badges should be changed? Every three months
When heat is produced in the tungsten target, what type of reaction is that called? Excitation
Is heat production an excitation interaction or is it an ionization interaction? Excitation
Who receives somatic effects of radiation? Exposed patient; these effects are increased incidence of cancer, effects on the developing embryo, cataracts, and life span shortening.
Use of a non-grid technique is implemented in? Extremity examinations.
Where are compensatory filters placed? Face of the collimator
What is the result of film speed on image resolution?
Faster speed = shorter exposure time but less resolution, Slower speed = longer exposure time but greater resolution.
State 2 AKA's for SID? FFD and TFD
The total amount of radiation received by a patient during radiography is chiefly affected by___? Field size being exposed.
Cathode's 2 primary parts: Filaments and focusing cup
X-ray of a thin mesh wire is to detect? Film screen contact.
Which part of the x-ray tube has to be heated if radiographs were to be taken? Filament (tungsten)
What are the four steps of film processing?
Film, developer, fixer, wash.
What should be done instead of using "split screens"? Why is this consistent with the concept of ALARA? Filters, to reduce exposure
Define inherent filtration. Filtration the pyrex gives you
The greatest radiation hazard to an embryo or fetus occurs during the? First trimester.
This processing solution is acidic? Fixer
Where does silver recovery happen? Fixer
Where would you find the clearing agent, hardener, and preservative? Fixer
Hypo is another name for? Fixer
This processing chemistry must be passed through a device to reclaim silver? Fixer
This processing solution is considered an environmental hazard? Fixer b/c of the silver involved
Sodium thiosulfate in a processing solution serves as a? Fixing agent (known as a clearing agent).
After leaving the developer the film is transported into a second tank, which contains_? Fixing contents
What causes radiographs to stain brown with age? Fixer problem / problem with fixer retention
What causes processed radiographs to stain w/ age and turn brownish-yellow? Fixer retention
Archival quality of film is established in this stage of processing? Fixing
What type of luminescence do our screen exhibit? Fluorescence
What are the four exposure factors involved in producing a radiograph?
Focal film distance (FFD), kVp, mA, and time.
At what specific point are x-rays formed/produced in the tube? Focal spot on the target of the anode
Describe the make up of the cathode? Focusing cup as well as the short and long filaments
What occurs if film screen contact occurs? Fog and Blur
What's most likely to occur with x-ray? Free radicals
In the X-Ray tube X-Rays travel from what to what? From cathode to anode
Describe the use of a compensating filter for a lateral spine shot. Utility if from L1 to L4 or 5
Name the projection which shows the L5 disc spaces with the best clarity? Frontal lumbosacral spot.
Which rectification is most consistent with ALARA. Full Wave Rectification
Which of these types of rectifiers produces the highest contrast radiograph? Full Wave Rectification
Which of the types of energies in the electromagnetic spectrum have the ability to ionize? Gamma and X-Ray
Red safe light is considered universal; name of safe light? GBX
This color safe light is used with other chromatic (green) film? GBX Red
How is a safe light filter installed? With the Gel substance on the outside so you should be able to read the letters.
What will happen to film if developing temperature is to warm? Gets Darker
What will happen to film if it spends excess time in the developer? Gets Darker
What are the general characteristics of an x-ray tube? Glass tube containing an anode and cathode. Cathode (-) end has a coiled tungsten wire filament within a focusing cup.
What happens to the original x-ray following the Compton scatter interaction? Goes on to other reactions and creates fog.
What type of chiropractic practice would require a relatively high grid ratio? Gonstead
State the unit of absorbed dose in Systems International nomenclature. Gray

What is the measurement of an absorbed dose of radiation (how much enters a patient)?

Films improperly washed after fixing would result in? Greasy appearance.
The advantage of a rotating anode over stationary anode x-ray tube is? Greater tube capacity for heat.
What color of light do rare earth crystals typically emit? Green and Yellow
Type of luminescence appropriate for intensifying screens? Green/yellow, rare earth type
What is the most common method of reducing scatter?
A thin sheet of metal (lead) which has a high atomic number and absorbs protons and electrons defines how a___works? Grid
Where is the radiographic grid placed? Grid is a.k.a. bucky so between patient and film
Efficiency of grid strongly dependent on? Grid ratio (Where efficiency = the cut in scatter)
Height of lead strips divided by width of lead strips is called? Grid ratio
The formula of kVp x mAs x 1.3 would be used for calculation of? Heat Unit.
Glutaraldehyde is used to retard the swelling of the emulsion necessary in automatic processors in which the film is transported by a system of rollers.  This is called? Hardener (During Developer stage)
Aluminum chloride functions to shrink and harden the emulsion.  This process is called? Hardener (During the Fixer stage)
In pediatric radiography, how should a child be stabilized? Have the parent/guardian hold the child still.
Number of electrons that pass through the x-ray tube for any given exposure is chiefly dependent on? Heat of the filament.
Variation of the x-ray intensity along the tube axis is known as the? Heel effect (One side strong the other side weaker)
Grid ratio is? Height of the lead strip divided by width of interspace
The collimator functions to? Help reduce scattered radiation.
What type of tissue most likely to undergo photoelectric interaction? High atomic #
Photoelectric absorption interaction = High atomic #
To maintain optimal film contrast in higher kVp exams, ___grid ratio is important. High
Which type of rectification has the highest energy beam, shortest exposure time? High frequency
Which rectifier will provide the least radiation exposure to the patient? HIGH FREQUENCY (30% less)
Which x-ray generators produce highest energy photon consistently? High frequency x-ray (Not single or triple phase and not digital)
Which rectifier will give the least radiation to the patient? High frequency (about 30% less)
Which of these types of rectifiers produces a beam with the highest energy x-rays? High Frequency Rectification
Which of these types of rectifiers can be plugged in to a 110 outlet? High Frequency Rectification
Which of these types of rectifiers will extend the tube life? High Frequency Rectification
Which of these types of rectifiers reduces patient exposure by at least 30%? High Frequency Rectification
What grid permits the least degree of error? High Ratio in terms of lateral angle
Quantam mottle is caused by? High speed/screen film combination
What is the relationship between grid ration and radiation exposure? Higher ratio, the more exposure. Higher grid ratio, less consistent with ALARA
Which is most consistent with quantum mottle? Higher speed
How is system speed related to detail? Higher speed, detail decreases
Name the two persons responsible for plotting of the characteristic curve? Huerter and Driffield
Define manifest image? Image on film after processing.
Define latent image? Image on film before developing
To avoid being exposed to x-rays, how long must you wait before entering the x-ray room, after the exposure is terminated? Immediately
In humans, what type of ionization is most likely to occur? Indirect effect.
Central ray may be angled in this direction when using a linear grid. In the direction of the strips, in our case, cephalad and caudal
Where is the hardener found in manual processing. In the fixer
Automatic processing, where is the hardener? In the fixer and developer. Please note that the fluids turn to a gelatin emulsion when it is wet, turns to jello, so its also in the developer to prevent this reaction.
What are three things that can increase scatter? Increased patient size, increased kVp, and increased field size.
Doubling the FFD during X-ray examination requires___ to maintain the same film density? Increase of the mAs by four times (2 x FFD x 4)
How is film contrast related to film latitude? Increase contrast - decrease latitude (Inversely related)
A decrease in grid ratio will? Increase film density.
How does mA effect radiographic density? Increased density (blackness)=mA controls number (quantity) of electrons produced and has most effect on blackening. Increased mA
How does kVp effect radiographic density?
Increased density (blackness)=Controls the voltage between cathode and anode.  Increased kVp
What occurs as kVp is increased?
Increased density (blackness)
The purpose of the rotating anode is to? Increase the tube capacity for heat.
Secondary radiation affecting the film is increased by? Increase in kilovoltage (Compton effect)
As room temperature increases, the speed of the film? Increases
Compton scatter increases with? Increase in kV, field size, and decreased image distance
When you need to double density what do you do to KVP? Increase it by 15%
Though kVp is not the controlling factor of radiographic density, to double radiographic density using kV? Increase kV 15%
What occurs when mA is increased?
Increased density (blackness)
If MAS is reduced by 50%, how much should you change KVP to get equal density? Increase KVP 15%
Double radiographic density using kvp? Increase kvp by 15%
Describe effect of crossover on blur? Increased Blur (crossover = light striking through all parts of screen as it crosses through).
Why is it a problem to use a bucky if one isn't needed? Increased Exposure
What is the effect of increased and decreased time in the developer on the exposure of the film?
Increased time = blacker, decreased time = lighter
As KVP increases what happens to Compton scatter? Increases - direct relationship between the two
Name one disadvantage to using a grid? Increases patient exposure.
What are two things that effect cosmic radiation?
Increases with altitude and latitude (north pole)
How does collimation to the smallest field size effect radiographic contrast? Increasing film size reduces scatter radiation.
Field size, thickness of the body part and kVp all do what to scatter? Increase scatter-↑ body part thickness, ↑ Field size and to a lesser degree ↑ kVp, all ↑ Scatter (Low kVp increases dose so in practice we maximize kVp.
What is the Relationship between SID and Distortion? Indirect
Which is most likely to occur in human tissue? Indirect effect (Mutate to change rather then directly changing genes)
Describe the relationship between photon, wavelength and energy? Indirect relationship
Which shell level is ionized in the photoelectric absorption interaction? Inner Shell
Photoelectric effect involves? Inner Shell electrons-involved in diagnostic x-ray
I/I*=(D*)2 / (D)2 = Inverse Square Law
Double the FFD will give 1/4 of exposure? Inverse Square Law thus increase mass by 4 times
One half of the FFD will increase exposure 4 times? Inverse Square law thus decrease mass by 4 times
Triple the FFD will give 1/9 of the exposure? Inverse Square law
One third of the FFD will increase exposure 9 times? Inverse Square law
The film latitude varies___with film contrast? Inversely
What is the relationship between crossover exposure and blur? Inverse, decrease crossover = increased blur
Describe the relationship between SID and magnification distortion? Inverse
Describe the relationship between film screen system speed and sharpness? Inverse
How is a photons wavelength related to its energy? Inverse
What is the relationship between x-rays and wavelength? Inverse
What is the relationship between voltage ripple and x-ray energy? Inverse (as ripple increases, x-ray decreases)
What is the relationship b/w frequency and wavelength?: Inverse relationship
What is the relationship between Compton Scatter and collimator field size? Inverse, as you increase collimation you decrease scatter.
How is photon wavelength related to it's energy? Inversely
How is a photon related to its energy? Inversely
How are contrast and latitude related?
Inversely. High contrast = low latitude (few shades of gray), low contrast = high latitude (increased number shades of gray)
What is the relationship between SID and magnification? Inverse
What is the Relationship between frequency and wavelength? Inversely proportional
Intensity Equation Inversely Proportional (old/new = new2/old2)
What agent is commonly used in studies of the vasculature? Iodine.
State at least 2 advantages of performing PA lumbar spine examinations instead of AP. It decreases radiation dose to the gonadal region, decreases scatter and Improves detail.
Application of what principal/rule minimizes radiation exposure dose to the patients? Inverse square law.
As quality assurance of our X-ray units & darkroom equipments___? It is acceptable to take experimental x-ray films of either phantom parts or other objects first, run it through the processor, before accepting the first patient.
State at least 2 advantages of tissue compression It decreases the number of atoms in the path of the travel of the x-ray.
Decreased patient thickness = Decreased Compton Scatter
Where should the anode side of the tube be placed when performing a lateral cervical spine radiograph? It doesn't matter on a 10x12" film at 40"
Why is the processor lid left open when the processor is off? It gives the liquid the opportunity to cool off to room temperature and
allows the developer and fixer to rise to the top without settling back down and avoids cross contamination of developer to fixer.
Purpose of using an airgap?. It increases OID, to decrease scatter without using a grid
What is a gamma ray? It is a high energy ray that comes from inside the nucleus.
What is differential absorption? It is the difference between what is absorbed vs. what is transmitted.  Helps to determine radiographic contrast.
What does kVp do inside the tube to produce x-rays? It is the technical factor that controls the energy of the electron.
What happens to the original x-ray following the photoelectric interaction? It is totally absorbed resulting in the bright areas on the radiograph
How does placing the anode / cathode side in the proper place affect the radiograph's overall density? It produces uniformity in density
What is radiographic density? It refers to the film's degree of blackness.
What is ionizing radiation capable of doing to an orbital electron?
It can remove an orbital electron from the atom with which it interacts - the result is an ion pair. This occurs when an x-ray passes close to an orbital electron of an atom and transfers enough energy to remove it.
Which Characteristic X-rays of tungsten are energetic enough to be useful? K-Characteristic
Which characteristic x-ray are useful in tungsten target? K-shell
For every degree increase in the developer for manual developing? You have to add 15 more seconds
Which exposure factor controls differential absorption? kVp

What exposure factor controls the voltage differential between the cathode and anode?

Kilovoltage anode-cathode circuit (kVp)
The exposure factor that produces the longest scale of contrast? kVp
Secondary radiation is increased with higher___? Kilovoltage (Increased compton effect)
Why does high kVp give less contrast?
kVp photons are less discriminating and pass through all materials easily with less difference between tissues
Technical factor that controls wavelength of x-rays in the beam? kVp
What is the wavelength of an x-ray dependent on? kVp
What factors control x-ray energy? kVp
What is the highest energy X-ray in the beam dependent on? kVp
State the formula for heat units? kVp x mA x time
What is the formula for heat units? kVk x MAS
Radiographic contrast is controlled by? kvp/mAs relationship
Where should the compensating filter be placed for a lateral lumbar? L1-L3
When does the anode heel effect become important in terms of film size and source image distance (SID). Large film sizes at short SID
How does increasing the distance from the film affect the sharpness of the image on a large and small focal spot? Large focal spot = fuzzier and more distorted while a small focal spot = still sharp image,
What are the two filament sizes and how does filament size determine the focal spot size (how compact the x-ray beam will be)? Large and small. A small compact beam gives a sharper image but can tolerate less heat.
Which view best depict lumbar IVF's? Lateral view
Describe a radiograph taken at the improper grid radius? Laterally underexposed (white)
Radiosensitivity of tissues depends on the degree of undifferentiation of cells i.e. Lymphocytes more sensitive then nerve cells is called? Law of Bergonie & Tribondeau
Radiation that comes from tube housing in areas other than port? Leakage
What is the radiation that comes from the tube housing (other from the port) of the tube? Leakage radiation
For any given film dose, skin entrance dose for the patients is___when the films are taken with a longer FFD? Less.
Two benefits to using compensating filtration? Less exposure to the patient and a more uniform density on the film
Why is a cross hatch grid not recommended? Less room for error, and you have to aim the beam perfectly, no angling in any direction, much more sensitive to short or long SID's
What is the level of female exposure for which there is no risk of having an abortion/getting an abortion? Less than 10 RAD
Define LD 50/30? Lethal dose mean 50% of population dies in 30 days
Men who had ankylosing spondylosis had an increase in? leukemia
Shortest latent period of cancers? Leukemia
Name two radiation induced malignancies? Leukemia and thyroid cancer
Of Radical induced cancers, which has shortest latent period? Leukemia only 7 yrs.
Name two more radiation induced malignancies? Leukemia, skin, bone, lung, thyroid, and breast cancer.
State the wave equation? Light = wavelength x frequency
How do you know the dead man switch exposure is terminated? The light goes off
How do you know x-rays are produced and are terminated? The light goes off
Describe the appearance of grid cut off due to lateral exposure? Light on one side
Dust on an intensifying screen results in? Little white specks.
What reduces scatter radiation? Longer FFD, use of the air gap technique or use of a grid.
This type of contrast is produced by High KVP, Low MAS techniques: Long Scale
What does the term film latitude mean? Longer scale - tolerate error
Secondary radiation usually has___wavelength than the primary radiation? Longer
Which view demonstrates the lung apex the best? Lordotic chest (Pancoast tumor)
What procedure is used to perform a pulmonary examination? Lordotic view
Shallow breathing is recommended in which view? Lateral thoracic spine to blur out the ribs.
Full exhalation is recommended in which view? Lower ribs.
Two probabilities that an electron will undergo photoelectric absorption interaction? Low energy and high atomic number
Tube overload corrected by? Lower mA and increase time
The exposure factor that produces the least heat units would be? Lowest time
List the variation in cell sensitivity from most to least sensitive? Lymphocyte, erythrocyte, epithelium, endothelium, con tissue, bone, muscle nerve, brain.  Nerve and brain cells not turned over so less sensitive.
The exposure factor that produces the the greatest film density? mA
What factor is selected to select filament size? mA
The focal spot size is dependent on this exposure factor? mA
Air gap technique produces? Magnification of body parts.
One disadvantage to grids? Significantly higher patient exposure.
What are two sources of ionizing radiation?
Man made and natural.
Define linearity? Manipulating the MA and time to get the same MAS
Electrical unit that controls total number of x-rays? mAs
What is the controlling factor for Radiographic density? mAS
What controls the number of x-rays in the beam? mAS
This exposure factor controls the quantity of the x-rays in the beam? mAs
The # of x-rays in beam is controlled by? mAs
When collimating down "significantly", what must be done to maintain radiographic density? mAs must be increased by 50%
State the formula for heat units? mAs x kVp
LD 50/30: Means lethal dose where 50% of exposed population dies within 30 days
The view that shows the ankle mortise joint the best is? Medial Oblique.
Reduction of silver bromide into metallic silver during development is by? Metol and hydroquinone  which are reducing agents.
Film badge reports express occupationally exposed persons dosage in these units? Millirem seivert
Purpose of control badge? Monitors transport RAD
How often are film badges monitored? Monthly
Collimated field size and scatter production? More collimation, less scatter
A Bucky is also known as a? Moving grid
Ability to manipulate mA and time and get the same image? Linearity:
What charge is on the focusing cup? Negative
What is the disadvantage of using a grid? Need to increase mAs 2 to 3 times when using grids vs non-grids.
Which view best demonstrates a posterior dislocation of a metacarpal bone? Neutral lateral view.
As film is removed from the developer, development continues because of soaked up solution by the emulsion.  To stop this action and prevent overdevelopment and fogging of film, acetic acid is a? Neutralizer also called activator
Film badges should___ be worn by radiation workers when going to medical or dental x-ray's themselves? Never
How often must lead walls be replaced? NEVER; it is impossible to contain an X-ray
Is a gamma ray always higher energy than an x-ray? No
Will you, as a chiropractor, ever use gamma rays in your practice? No
Will exposure to x-radiation leave matter radioactive? No
Do all of the x-rays in the beam have the same energy? No, it's Heterogeneous
10:25 rule of thumb for fetal radiation exposure and abortion. No fetus should be aborted if haven't received more than 10 RAD, 11-25 gray area (parent's decision) and over 25 advised to abort.
Describe an x-ray photon in terms of mass, charge and velocity? No mass or charge and moves at speed of light.
Severity of symptoms depends on the number of exposures called? Non-stochastic effect because there is a threshold for somatic disease.
Is it really the x-ray that interacts with the film emulsion to produce the image? No, chemical processing is needed in order to convert the invisible latent image into a visible image.
Does the power company provide DC current? No, only AC
Do all of the electrons have the same velocity as they pass from cathode to anode? Why? No.  When the electrons from the cathode hit the tungsten anode they suddenly stop and give up their energy.
What should be used to clean an intensifying screen? Non lint screen cleaner
Describe electromagnetic energy in terms of:  Mass, Charge and Velocity None, None, Speed of Light
Hormesis: Notion that some radiation may be actually good for you.
Pair product interacts with? Nucleus or nuclear interaction-not in diagnostic but found in x-ray treatment
Which occupation expose the worker to the least amount of occupational exposure but seems counterintuitive? Nuclear power plant employees
Visualization of grid lines on an exposed radiograph suggest? Off-centering of the grid in relationship to the tube.
Which view show the Sacroiliac joint the best? Oblique lumbopelvic spine.
From a PA view of the hand, how is the thumb being projected? Obliquely.
What is contained inside the large transformer besides the coils? Oil
State 2 of the 3 grid motions? Oscillating, reciprocating
Where should personnel wear a dosimeter? On a collar (and on the outside of an apron if wearing one)
Literally, where are compensating filters placed in system? On collimator
Personnel dosimeter should be warn? On the collar or outside the apron
Where are compensating filters placed? On the face of the collimator
Where is the film's expiration date located? What is the result of using film that is out of date? On the packaging, fogging.
How often should the entire processor be drained, cleaned and replenished? Once a month. The most it should go is 6 weeks. Costs roughly $100
per clean up.
Describe grid cut off with lateral angulation error? One side underexposed
What is the 10 day rule? Non-urgent diagnostic radiography of the abdomen should be confined to the pre-ovulatory phase of the menstrual cycle, i.e., the ten days following the first day of the last menstrual period, on the assumption that ovulation occurs at about mid-cycle.
Another way to explain 10 day rule? 10-day interval following the onset of menstruation (1st ten days of menstrual cycle)
10 day rule from Appendix 4 page 74 Radiologic Health Branch California DHS? 10 or 14 days after the onset of menses it is improbable that a woman would be pregnant and thus are safer times to perform X-ray examinations.
What is the difference between X-ray and gamma ray? Origin (gamma ray comes from nucleus).
Which shell level is ionized in the Compton scatter interaction with matter? Outer Shell-as found in diagnostic x-ray.
In Compton scattering the photon interacted with the? Outer Shell
If a technologist wears a lead apron, the dosimeter should be worn? Outside of the apron.
What would the image look like if the developer was too hot? Overexposed (Creates Developer Fog.
What would the image look like if the developer was too concentrated? Overexposed (Fog)
Poor film screen contact can be created by? Warped cassettes, loose hinges and foreign objects inside.
Tungsten is used as a target material.  It has electron shells from "K" near the nucleus out to___? P
Electron transmission in tungsten produces highest characteristic x-rays? P to K
The Characteristic X-ray with the most KEV of energy occurs with this electron transition? P TO K
This electron transition in tungsten produces the highest energy x-ray? P to K transition
Which electron transition in tungsten makes highest energy x-ray? P-K
Of Par, high, rare earth, short focal film distance or combination screens, which allows for the best definition and details? Par speed screen.
Which view demonstrates the pars? Oblique
What type of grid should you buy if you are using both 14x36 @ 72 SID and 14x17 @ 40 SID? Parallel
There are 3 types of grids - name them Parallel Linear, Crosshatch, Focused Linear
Compare particular matter to electromagnetic in path through matter. Particular has shorter path in matter.
TheTunnel view of the knee should be take? With the patient prone.
The transmission of the x-ray beam through a thick protective barrrier is closely related to___of the tube? Peak operating potential (Peak kVp)
Calibration of the x-ray unit? Penetrometer
Describe degree and direction with crosshatch grid: Perpendicular and no angle
Describe the degree and direction that can be used with a single cross hatched grid? Perpendicular, no degrees
Which x-ray interaction with matter is more likely to occur with high atomic number tissues? Photoelectric Absorption
Which x-ray interaction with matter is most likely to occur at energies between 10-60 keV? Photoelectric Absorption
What x-ray interaction results in inner shell ionization? Photoelectric absorption
Interaction w/ matter that results in inner shell ionization? Photoelectric absorption
What happens to the X-Rays in photoelectric interaction? Photoelectric absorption
White areas on film are a result of this X-Ray with matter? Photoelectric absorption
In this interaction the photon is totally absorbed? Photoelectric absorption interaction
Use of contrast agent in diagnostic x-ray (Barium) is dependent on their ability to enhance___? Photoelectric effect
Photon interacts with bound inner shell electron,electron is liberated from the atom (ionization), with Photon disappearance is called? Photoelectric effect (Electrons in higher energy shells cascade down to fill energy void of inner shell).
Describe classical scatter in terms of energy loss and change of direction? Photon strikes the atom, it interacts with the outer shell and gives up no energy but does change direction
Describe pair production? Photon hits the nucleus an disappears but and electron and positron are created.
What is the film base made of? Polyester-Plastic
Define what a PBL? Positive Beam Limitation, its a collimator
Sodium sulfite helps protect the reducing agent from oxidation because of their contact with air.  It also reacts with oxidation products to reduce their activity.  This is called a? Preservative (During Developer and Fixer in Automatic Processing)
What different types of exposure are allowed in a controlled area vs. uncontrolled? Primarily occupied by radiation workers, people who also may have a benefit
rather than a risk.  The controlled area can receive up to 10 times the exposure of
the uncontrolled area
Define grid radius? Proper SID range or  (Grid radius applies to focused linear grids)  it is the distance from the surface of the grid to the point above the grid where all of the strips would meet.
What two things does kVp control?
Quality and quantity of electrons (energy)
Proper name for film graininess? Quantom Mottel
State the unit that a physicist would use to describe ionizations in air in classical nomenclature? R
State the unit of absorbed dose in classical nomenclature. RAD-Radiation Absorbed Dose
State the formula for Rem. Rem = _____ x _____. RAD x QF
What is the formula for REM? rad x quality factor
Define leakage radiation. Radiation other than the primary beam
Orthocromatic film matches with these screens. Rare earth
State three other names for the Coherent scatter interaction: Rayliegh, Thompson, and Classical
What is remnant radiation? Rays that interact, make the image. Transmitted and scattered rays
State 2 of 3 grid Motions: Reciprocate, Single Stroke, Oscillating
What color safe light do you need for orthochromatic film screens? RED
Color safe light required to be used w/ rare earth film screen combos? RED
What color do safe lights need to be? Red
This color safe light filter is required for rare earth film screen combinations? Red, GBX
X-ray films are least sensitive to___light? Red
Crystals of the Intensifying screens do not usually emit___light. Red
The primary purpose of a filter used in diagnostic x-ray machines is to? Reduce the skin dose
What is the purpose of radiographic grid? Reduce Compton Scatter
What is the advantage of using air gap technique? Reduce patient exposure
What is the main purpose for intensifying screen? Reduce patient exposure
Three advantages of tissue compression? Reduce scatter, less exposure, improves contrast, improves detail, can decrease ovarian disease
Exhausted developer will have? Reduced alkalinity.
What is the processing order to "develop" a film? Reducer/developer (phenidone, hydroquinone), Accelerator/activator (Sodium carbonate), Preservative (Sodium Sulfite), Restrainer (Potassium bromide), and Hardener (glutaraldehyde).
Chemical reduction of exposed silver bromide grains to convert them into visible metallic silver.  Phenidone for mid to lower gray scale and hydroquinone for dense, or dark areas.  This is? Reducer in the Developer stage
Relationship between the reflective layer and screen speed? Reflective layer and screen redirect isotropic rays going away from the film. more light makes it to the film, so the speed of the system is greater.
State the unit for occupational exposure in classical nomenclature? Rem
Dose or radiation equivalent in man? Rem = unit of radiation-Roentgen-equivalent-man
Describe a long latitude film. Responds to a wide range of useful densities, but it has specific characteristics.
Potassium bromide is used in an x-ray processing solution as a? Restrainer (In Developer).
What is the function of the potassium bromide mentioned above? Restrainer use to moderate the rate of development.
Voltage occurring at different speeds at peak? Ripple
Classical x-ray unit for intensity of x-ray in air? Roentgen
What does developer roller look like? Rubbery and the other one is Wood
Old formula for determining the maximum cumulative exposure for a occupationally exposed person? S(n-I8)
Why is the inverse square law important?
Safety issue = increased distance = less intensity and less exposure to staff.
What is continued emission of light after the energy has been turned off from the crystal? Screen lag, or afterglow.
What is the major source of radiation exposure to restraining personnel and cause of poor radiographic detail?
Grids and Air Gap Technique (gap between pt and film) help control? Scatter radiation
Secondary barriers are built to be exposed to___? Scattered radiation and leakage radiation.
According to Gurney-Mott theory, this is the latent image formation center? Sensitivity spec
The greater the grid ratio, the greater is the? Secondary radiation absorbed.
Independently, both grid ratio and ↑ KVP cause? Secondary radiation increase.
↑ Compton effect is associated with higher KVP causing? Secondary radiation increase.
State the advantage of using small focal spot size? Sharper image
Name 4 RAD protection devices? Shielding, collimation, Increased developed system speed, opt. KVP, filters, intensifying screens
Use of high speed intensifying screens instead of direct film exposure results in? Shorter exposure time required.
Chest x-ray exam should have? The shortest exposure time, higher kVp than a thoracic spine exam and never excessively collimate.
Apply higher kVp to x-ray tube produces? Shorter wave length x-ray's.
Describe the relationship b/w x-ray wavelength and energy? Shorter the wavelength, higher the energy...therefore inverse
List other types of electromagnetic energies in order of their energies relative to x-ray? Shortest to longest wavelength: Gamma, X-Ray, UV, Visible Light, Infrared, Micro, Radio
Describe SID and sharpness relationship? SID increases, sharpness increases
State the unit for occupational exposure in Systems International nomenclature? Sievert
What is the measurement of radiation dosage?
Sievert (Sv)
What is the unit of occupational exposure in SI? Sievert
Film emulsion has these crystals suspended in gelatin? Silver halide crystals
What will form if fixer is not washed off?
Silver sulfide (brown color)
Focal spot size is dependant on? Size of the filament
Cathode has two primary parts, what are they? Small and large filament and focusing cup
Use of small focal spot produces? Smaller penumbra
Geometric un-sharpness can be diminished by what two methods?
Smaller focal spot and shorter object film distance.
Which chemical prevents rapid oxidation of developer? Sodium sulfite (preservative)
What chemical governs the reducing activities of the developer? Sodium Carbonate
State the wave equation? Speed of light = wavelength x frequency
What does an Electromagnetic induction motor do? Spins the anode (has a rotor and stator)
What is the focal spot? Spot on the anode target where x-rays are produced
Black tree light defects have been found due to low humidity and ___________? Static Electricity
What causes spider-like marks on the films? Static Electricity.
What may appear on the film if the humidity is too low? Static, tree, crown, etc.
What are the two types of radiation injury?
Stochastic and deterministic (non-stochastic)
Occurs by chance (random), probability increases with dose but severity is independent of dose, occurs in exposed and unexposed people?  Stochastic characteristic effects (Example - cancer, genetic defects)
This type of effect is a random effect from chronic low dose exposure? Stochastic
Random effects such as cancer are called? Stochastic
70 year old suseptible so no threshold called? Stochastic effect.
Why is it important to have ↑mAs, ↓time? Stop motion
Charge on the focusing cup? Strong negative
Define total filtration? Sum of adherent + added filtration
For an AP view of the elbow, how would the wrist be positioned? Supinated.
When an A-P thoracic is performed, which part of the body should the anode side of the tube be placed? T1-T6, the thinnest part of the body
What is the function of the fixer? Takes the emulsion and hardens it. It clears and hardens the film.  It cleans off the unexposed/undeveloped halide crystals off the film. They are dissolved off. When we do silver recovery to get it back and keep it out of streams of water we pass the fixer through a silver recovery device.
State the aka's for source image distance? Target film distance and Focal film distance (TFD & FFD)
What is a TVL? Tenth value layer, thickness of a material that will reduce the intensity of the beam to one tenth it's value
Linearity? The ability to change mA and time and get the same amount of mAs
Define ionize? The ability to give an atom or group of atoms a net electric charge by adding or removing one or more electrons
Latitude? The ability to make mistakes.
Which side of a radiograph will exhibit the least radiographic density? The anode
What is radiographic density? The blacks on the film
This side of the radiograph will have the most blur, what side is it? The cathode
Replenishment rates are dependent on? The direction of film
How much chemistry goes in versus how much goes out depends on? The direction of film feed on tray
The central ray is aimed in this direction using a linear grid? The direction of the strips...usually cephalic/caudal, vertical
What is the energy unit of a proton?
The electron volt (eV)

What is radiation?

The emission and transfer of radiation in space
A cathode has two primary parts, what are they? The filaments and the focusing cup.
Silver is reclaimed from? The fixer
What determines the energy of the x-ray? The frequency of the x-ray wavelength.
Law of triboneau and Buscuia? The more highly proliferative the more sensitive
Define hormesis? The notion that some radiation maybe good for you
What is the difference between gamma rays and x-rays? The only difference is their origin.  X-Ray = Electron Cloud & Gamma = Nucleus
What is the difference between x-rays and gamma rays? The origin
What would the film look like if all of the x-rays interacted with the emulsion and the film was then processed? The portion next to the film base remains largely unexposed/black.
The anode side of the tube can be located by? The positive label, listening for the spin and finding the wire for the AC current.
What does the mA circuit control?
The quantity of electrons produced in focusing cup
How does focal film distance effect radiographic density?
The smaller the FFD, the greater the intensity of the beam and therefore greater resolution.
Blackening of a film can be due to? The speed of the film, a low grid ratio and photon energy reaching the film.
What makes an x-ray photon higher energy than a microwave? The wavelength is shorter.
Gurney-Mott theory describes? Theory of latent image and manifest image formation.
What happens to the original x-ray following the Coherent scatter interaction? There is a change in direction but no change in energy, therefore no ionization.
What is the unique mutation to radiation exposure? There is no unique mutation
How are Characteristic X-Ray's produced? These are produced when outer shell electrons fill inner shell vacancies due to the projectile electron hitting an electron and ejecting it from an inner shell.
What is the only similarity between particulate radiations that result from radioactivity and x-ray? They can ionize
What is the relationship between photon energy and frequency?  What happens to photon energy when frequency is increased?
They are directly related. Increasing frequency corresponds to an increase in energy.  If frequency doubles, energy doubles.
What is the relationship between frequency and wavelength? They are inversely related as c is a constant. C=frequency x wavelength
Define Half Value Layer - HVL? Thickness of certain material that attenuate radiation to one half of the original dose.
What are the three variables in a technique chart?
Thickness of region, kVp, and mAs.
What are characteristics of non-stochastic effects?
Threshold dose, below which there is no effect. Severity proportional to dose above threshold. Example - cataracts, erythema, main problem in radiation accident.
Careless manual handling of films with excessive bending of the film cause? Thumbnail or crescent shaped dark shadows on films.
3 examples of things associated with ALARA? Time, distance, shielding (cardinal principals)
How much more time does the film stay in the fixer than the developer?
Twice as much time.
Why do we have contrast in an image?  How does that happen? To allow for increased clarity, detail and resolution on the film.  Occurs as a result of some x-rays being absorbed and others interacting with silver metallic crystals creating radiographic density via differential absorption.
Why is the film loading bench grounded? To avoid static
Why is the water tank in the processor drained when it is off? To avoid the possibility of stagnation and algae growth. The fixer will be retained in the emulsion causing a smell and also turns a sepia color (looks like a rust/nicotine stain)
Why is the direction of film transport through the processor considered important? To avoid to much chemistry being concentrated in one area of the film.
Why is there lead in the back of the cassette? To prevent backscatter
List at least 3 consumer products that contribute to background exposure? Tobacco, Television, Combustible Fuels
If X-Rays turn yellow or stain with age what cause that? Too much fixer
Where is the floating lid? Top of developer in replenishing tank
Floating lid is in the replenishment tank? True
If you have a fixed kVp chart then you must have a mAs that will change? True
For every 4cm of tissue thickness increase mAs should be doubled? True
Long latitude films respond to a wide range of useful density? True
By federal law the machine must have total of 2.5mm lead equivalent? True
Which part of the x-ray tube has to be heated if radiographs were to be taken? Tungsten filament
The disk of the anode is made up of___? Tungsten
What is the x-ray tube target made of? Tungsten
Describe grid cut off SID is too Long? Underexposed on both sides
Describe grid cut off SID is too Short? Underexposed on both sides
Describe grid cut off when CR is off center? Underexposed on one side
Focus grid with lateral angulation? Underexposed one side
What would the image look like if the developer was too Cold? Underexposed/Underreactive
What would the image look like if the developer was too
What would the image look like if the developer was too
Grid cutoff is? Undesirable absorption of primaries
Latent image is? Undeveloped, unprocessed image in the corner
Type or grid cutoff that would occur if the central ray was off centered to a focused grid? Unilateral
Where should the anode side of the tube be placed when performing a lateral lumbar spine radiograph? Up
Where should the anode side of the tube be placed when performing an AP thoracic spine radiograph? Up
If compensating filter is used on a lat lumbar spine where should it be, up or down? Up
Where should the anode side of the tube be placed when performing a full spine radiograph on a 14 x 36" film? Up
If a compensating filter is used on a lateral lumbar exposure, in what direction should the thinnest part of the filter be pointing? Up (want the thinnest part of the filter on the thinnest part of the patients body.)
Percentage of time a primary beam is aimed at a particular wall is called it's? Use factor
How do you clean intensity screens? Use manufactures' cleaner and gauze.
Describe the appearance of oxidized developer? Used motor oil.
What allows various patient structures to be recognizable on x-ray images? Varying attenuating capability of the different body tissue to incoming photons.
State the wave equation? Velocity = Frequency X Wavelength
Which way do you angle CR with linear grid? Vertically
Lead glove is important for radiographer during? Videofluoroscopy.
What is the clinical significance of the heel effect?

Want to position thorax and abdomen toward the cathode side since they need higher energy to penetrate.

Why is the use of "split screens" considered obsolete? Way too much exposure to the patient.
List the order from most sensitive to least sensitive tissues? WBC, Epithelial cells, muscle and nerve cells
Which filter is useful for the dorsoplantar view of the foot? Wedge filter
What film will show flat feet? Weight bearing lateral.
Define ionize? When an electron is totally removed from an atom.
When to use a gonad shield? When it won't interfere with shooting.
When is the exposure terminated when using the dead man's switch? When you remove your finger from the switch.
Describe reproducibility relative to radiology? When you take the same exposure over and over again; you should get the same results.
Describe grid cutoff? Where the primary beam gets absorbed by the grid.
How does a radiographically dense area appear on the radiograph? Wherever the body tissue is the most dense, that's where the radiographic density is the least dense. i.e. Most white = least radiographically dense.  Mass per volume of black metallic silver
What color should your dark room be painted? White or a light color.
Dust on an intensifying screen will cause what visual effect? White specks on the film.
When an artifact is demonstrated on a film as a result of something on the screen, what color will it appear?  Will it be sharp or blurred?  Why? White, Sharp, because it is close to the film.
Only 1% of the energy is converted to___while 99% is converted to heat? X-ray
What are three examples of ionizing radiation?
X-rays, gamma rays, and ultraviolet light
Coulombs/kg measure these types of radiation only? X-ray and gamma-ray.
Compare the mass of an x-ray to an alpha particle: X-ray has no mass
Compare the mass of an x-ray to that of an alpha particle x-rays have less-they have no mass
Compare wavelengths of X-rays to radio waves? X-rays have shorter wavelengths
How are radiographic density and anatomic density related? X-Rays that absorb vs. X-Rays that transmit.   They are opposites-Inversely related.
10 day rule: X-Ray after 10 days following 1st day of period
Where is the central ray for an AP full spine film? Xyphoid process (T10-T12)
Compare wavelength of X-Rays to radiowaves? X-rays have short wave length
For the tunnel view of the knee taken PA, is there tube tilt and if so to what degree? Yes.  45 degree caudal tilt.
Can pregnant women take X-Rays? Yes
Can human cells recover from RAD damage? Yes
Does non-stochastic effects have a threshold? Yes they do
Why would you not want to purchase a crosshatch grid? You can't angle the central ray.
In Bremsstrahlung X-Ray production, X-Ray energies range from? Zero To Peak Energy Electron.

Editor's note:  Special thanks to Dr. Victor Tong, DC DACBR.  Good Luck. 

  Read past articles by "little guy" Dr. Scott Neff, BA BS MSOM MPS-BT DC DABCO DE IDE CFE ABDA FFABS FAABT DABFE FABFE FFAAJTS-IAPS-2010 graduate of the University of Health Sciences Antigua School of Medicine, West Indies

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