Exam 1 Flashcards
Types of Radiation
Electromagnetic radiation (EMR)
Particle Radiation
Ionizing
Non-ionizing
Which type of energy is primary with the production of xrays
Electromagnetic energy
What unit is EMR energy measured in
Electron volts (ev)
What is EMR measured by frequency in
Hertz
What is EMR measured by wavelength in
Meters
Do X-ray have long or short wavelengths
Short
How fast does EMR travel at
Speed of light
What are the bundles that photons travel in
Photons or Quanta
Does intensity of EMR change the farther it travels
Yes
What determines if a wave is ionizing or non-ionizing
Wavelength
What type of radiation has a very short wavelength and high frequency
Ionizing
How are wavelength and frequency related
Inversly
X-rays and Gamma rays are examples of what type of radiation
Ionizing EMR
Can electrons be removed from Non-ionizing radiation
No
Viable light, Infrared, Radio, TV are examples of what type of radiation
Non-ionizing
What type of radiation has Long wavelength and low frequency
Non-ionizing
What type of radiation is not on the electromagnet but is ionizing
Particle radiation
what particles are produced by particle radiation
Alpha and beta
Are alpha and beta particles more or less harmful than X-rays to humans
More harmful
Radon produces what type of particle when inhaled
Alpha
Dosimetry is the measurement of
Radiation
What measures radiation
Dosimeter
What is radiation measured in
Roentgen
Coulombs
What unit is used to measure the amount of radiation absorbed
Rad
What unit of measurement is used to determine biological effects of radiation to organs and tissues
Rad
What unit of radiation is used for radiation detection in reporting exposure
radiation equivalent man (rem)
Sievert (Sv)
Workers that might be exposed to radiation ware what on them
Film badge
What does a Film badge measure radiation in
rem/Sv
What unit measures the quantity of radioactive material
Curie (Ci)
The average person gets how many mrads each year
360
Natural radiation makes up what percent of our yearly radiation exposure
82%
What are the different types of Natural radiation
Cosmic
Terrestrial
Internal
What gas is released from uranium and is part of terrestrial radiation
Radon
Radon makes up what percent of our total radiation exposure
55%
what is the natural radioactive substance in living tissues
Nuclides
What is the largest contributer to man made radiation exposure
X-rays
What are the most common types of man made radiation exposure
X-rays
Nuclear medicine
Consumer products (TV,Satellites)
Nuclear testing/reactors
Do diagnostic x-rays have enough radiation to cause acute effects
No
What is the name for exposure to the entire body
Whole body dose
What is the name for exposure to the skin
Skin entrance dose
What is the name for exposure to a specific organ
Organ dose
What is the name for exposure causing tissue damage of the exposed individual
Somatic dose
Who do you need to contact if you accidently xray a pregnant women
radiation physicyst
What is the main effect after taking 2-10 Gy of radiation (200-1000 rads)
Erythema
What type of radiation dose that can cause damage to future generation (repro damage)
Genetic dose
What are the greatest effects of Genetic dose
Leukemia
Mutations
What is the name of the effect that states probability of a harmful effect increases with an increase in dose
Stochastic somatic effects
What is Determinstic somatic
Known effects increase with increase in dose
What are the short term effects of radiation
Erythema
infertility
blood forming damage
cataracts
What is Protraction
If exposed at a low level continuously, effects are reduced
When is protraction used
Radiotherapy
Radioactive implants
What is Fractionation
Non continuous exposure to high doses reduces effects
What is radiation hormesis
The apparent beneficial effects of radiation
What is most likely to be caused by 200-1000 rads acute whole body
Hematological syndrome
What is most likely to be caused by 1000-5000 rads
Gastrointestinal syndrome
Death
What is most likely to be caused by 5000 or more rads
Central nervous system syndrome
Death
What are the stages of Acute radiation sickness
Prodromal stage
Latent stage
Manifest stage
Healing or death
What is LD 50/60
exposure that will kill 50% of the people in 60 days
What is LD 50/30
Exposure that will kill 50% of the people in 30 days
What is the LD 50/60 for humans
350
What is the LD 50/30 for humans
300
What was the first X-ray printed
Bertha’s Hand
Who discovered X-rays
Wilhelm conrad roentgen
Who was the first to use X-rays for chiropractic
BJ
What type of material absorbs X-rays
Dense material
What direction do x-rays travel in from their source
Diverging straight lines
What colour does the film turn when exposed to X-rays
Dark
Are X-rays stored in matter
No
Can X-rays be focused, reflected or refracted
No
What things are needed to produce an X-ray
A source of electrons
A way to accelerate them at a high speed and a hard surface to bounce them off of
Once X-rays are produced in the tube what do they hit next
A filter to remove weak electrons
What do we use to limit the amount of spray of electrons
Collimator
After passing through the patient what do X-rays hit next
A grid
What is the purpose of a Gird
remove secondary rays that out patients has produced
What is the metal encasement around the tube
Tube houising
What is the tube housing lined with
Led
What is between the tube housing and the tube glass
Oil (keeps it cool)
Where do x-rays exit the tube
Window/ port
Radiation leakage form the tube housing should be no more than what
100 mr/hr @ 1 meter
What hold the tube are in place
Tube arm
What hold the tube arm
Tube stand
What does the tube stand sit on and allows it to move horizontally
Tube track
What holds the tube arm and stand in place
Automatic locks
What contains the functional parts of the tube
Glass tube (glass envelope)
What is the name of the rays that exit the window
Useful beam
What is the center most ray, what direction is it compared to the patient
Central ray, perpendicular
Is there in any gas in the tube
No
What is the negative electrode called
Cathode
What are the 2 functions of the Cathode
Produces electrons
Focuses electrons
What are the two parts of the cathode
Filament
Focusing cup
What is the Filament made up of
Tungsten
What is it called when electrons are boiled off of tungsten
Thermionic Emission
What determines the amount of electrons released by the tungsten filament
Current
Most cathodes contain 2 filaments. Which filament is used to produce clearer images
The small filamaent
Which filament can handle more heat
Large filament
What do filaments sit in
Focusing cups
What do anodes produce
PHotons
What are the functions of the anode
Stops electrons = make xrays
Dissipates heat
Conducts electricity
What are the 3 parts of the anode
Target
Stem
Rotor
What part of the Anode emits xrays
Focal spot
How can you improve the clarity of the image using the focal spot
Make it smaller
What is the advantage of a large focal spot over a small spot
Handles heat better
What are the two types of Focal spots
Actual and effective focal spot
What focal spot is where electrons hit
Actual
What focal spot is where Photons exit
Effective
What is the term used to describe unclear boarders produced by xrays
Penumbra
What is the term used to describe clear boarders produced by xrays
Umbra
A large focal spot will produce what type of boarder
Penumbra
A Small focal spot will produce what type of boarder
Umbra
What type of tube has a small and large focal spot
Dual focus tube
What are the two types of anodes
Stationary
Rotating
When are stationary anodes used
Small exposures
What is the focal sport called on a rotating anode
Focal tract
What is the Line focus principal
Small angles = small effective focal spot
Large angle = large effective focal spot
What is the anode heel effect
Xrays that exit the heel and embedded in the target this reduced bean intensity and absorbs weaker rays
What direction should the anode and cathode be when doing full spine
Anode up
Cathode down
What are the two ways Xrays are produced
Bremsstrahlung radiation
Characteristic radiation
What is the Bremsstrahlung radiation effect
Electrons pass close to the nucleus of an atom, loss energy, the lost energy is converted into an Xray
What makes up the majority of Xray beams
Bremsstrahlung radiation
What is Characteristic radiation
The incoming electron hit an orbiting electron and bounces it out of orbit. Electrons in higher orbits then move to replace the knocked out on, this produces an Xray
What is it important to filter out soft rays out before they hit the patient
It would increase skin and organ radiation
What are the two types of Filtration for Xrays
Inherent
Added
What is Half value layer (HVL)
The amount of material needed to reduce the beam intensity by 1/2
What is the filter that is installed by the manufacturer
1-2mm of Aluminum
How much filtration is required for 70-100kV
2.5mm of aluminum
How much filtration is required for 125kV
3mm of aluminum
What is the function of the beam limiting device
Restrict the beam size
What is the beam limiting device used today called
Collimator
What are the shutters of the collimator made of
Led
What causes collimation cut off
when collimation is smaller than film size
What is it called when collimation is too tight
Over collimated
What is it called when collimation is too large
Under collimated
What are the 3 types of Collimators
Manual
Semiautomatic
Automatic
What types of collimators are Positive beam limitators (PBL)
semi and fully automatic
What type of collimation has the operator make all the adjustments
Manual
What type of Collimation tube distance must be set prior to collimation
Semiautomatic
What type of collimation tube has the shutters automatically set to film size after distance is set and film holder is put into the tray
Automatic
Where should compenstating filters be placed
Between patient and tube
What type of filter compensates for patients varied thickness
Compensating filter
What are the name of compensating filters that are placed on the front of the beam limiting device
Portal filters
What are compensating filters made of
Aluminum
Copper
What type of filters have a gradual taper
Wedge filters
What filter is most commonly used in chiropractic
Nolan filter system
What are underpart filters
Filtration between patient and film
What is and about underpart filters
They increase patient exposure
What is the most common form of Underpart filters
Split screen filters
What can cause Tube failure
Too much heat from holding rotor button down
What can excessive exposure cause or insufficient cooling
Anode pitting
How can you prevent thermal shock to a tube if it hasn’t been used in a while
Warm up procedure
Will a lower mA setting increase or decrease tube stress
Decrease tube stress
What do transformers do in a generator
Change incoming current
What does a high voltage transformer do
Converts volts to kilovolts
What does a Filament circuit transformer do
converts amps to miliamps
What do rectifiers do in generators
Convert AC to DC current
What type of current does the tube need to produce xrays
DC currents
What type of current do we get from the wall
AC
What is kVp
Kilovolt peak (max amount of energy per peak)
What is the difference between AC and DC current
AC = sin wave DC = Never cross 0, either only positive or negative
What type of generators have 1 line source and have maximum ripple
Single phase generators
What type of generator has 3 separate but intertwined lines that allows for more peaks and less dips
3 phase generators
What type of generators have no ripple and allows more accurate + predictable output
High frequency generators
What are advantages of High frequency generators
Fewer soft rays
Less exposure for patient
Affordable
What controls the length of the circuit
Time circuit
What is the usual exposure time
1/120th of a second to a few seconds
What are the different types of timers
Synchronous
Electonic
mAs + automatic exposure control
What times are more accurate and versatile
Electronic timers
What are the main factors controlling X-ray exposure
kVp
mA
Time of exposure
Distance
What is the distance from tube to film called
Source-image distance (SID)
Focal-film distance (FFD)
What controls the quantity of xrays hitting the target
Distance
WHen you increase distance what happens to the colour of the film
It is lighter
What is the law that causes image size to decrease as distance increases
Inverse square law
What are the two standard tube distances
72’
40’
What are secondary factors that control xray exposure
Field size
Compensating filtration
What must a patient do prior to being xrayed
Remove metal, or anything that might interfere with the xrays and create artifacts
How can we protect the patient with xray exposure
Only expose if needed Limit exposure Reduce retakes Shield radio sensitive parts don't xray a pregnant woman Monitor all patient exposures
What is the acronym used to keep patient dose as low as possible
ALARA (As low as reasonably achievable)
What is the agency is responsible for trying to keep patient exposure to a minimum
NCRP (cational council on radiation protection)
A gonadal shield on the collimator is called
Shadow shield
A gonadal shield on the patient is called
Contact shield
Which trimester is the fetus most radiosensitive
1st trimester
What characteristic of an organism determins rediosensitivity
metabolic rate
What is the name of the rule in which it is the safest to xray a female in child baring years
10 day rule
What is the 10 day rule
It is safest to xray a female the first 10 days after menstration
What is the most important way to protect yourself when xraying a female
Document that they say they are not pregnant in case they are and dont know it yet
