RT 110 midterm stuff .txt
Card Set Information
RT 110 midterm stuff .txt
List particulate radiation
What % of medical radiation is responsible for radiation exposure today?
Roughly about 50%
The amount of energy absorbed becomes the absorbed dose which is measured in what?
Rads or Grays
What is this called when the beam interacts with tissue?
Attenuation can occur thru what types of effects?
Absorption (photoelectric effect)
Scatter (compton effect)
Does absorption (photoelectric effect) occur in the outer shell or inner shell electron?
Inner shell electron
Does scatter (compton effect) occur in the outer shell or inner shell electron?
Outer shell electron
Radiation produced in the tube and traveling is called the...
The higher the kVp, the _____ absorption to occur. less or more?
The higher the kVP, the ____ scatter to occur. less or more?
What are the three basic components of reducing radiation exposure?
When should the radiologic technologist be exposed?
During fluoroscopy exams
For the inverse square law, as the distance doubles, what happens to the exposure factor?
It decreases by a factor of 4
What is skin erythema dose and how many rads does it take to get skin erythema?
How much exposure it takes before the skin turns red
What is Roentgen?
Unit of exposure in air
How much air is being ionized
What is REM?
radiation equivalent man
any exposure that produces the same biologic effect as 1 rad of x-radiation
What is Rad?
what the patient gets
depends of types or tissues
100 rads = __ gray
100 rems = __ sievert
X-rays are a __ LET form of radiation. (low or high)
List these from lowest quality factor to highest quality factor (the higher, the more dangerous). x-ray photons (beta particles and gamma photons), thermal neutrons, fast neutrons, alpha particles
x-ray photons (beta particles and gamma photons)-1
Radiation weighting factors are based on?
RBE-relative biologic effectiveness
They take into account specific cells and tissues
For diagnostic radiography weighting factors are used
What takes into account that different types of radiation are more dangerous than others and applies a radiation weighting factor to them? Equivalent dose or effective does?
What takes into account that different types of tissues are more sensitive than others and can potentionally cause more damage when irradiated? Equivalent dose or effective does?
Low energy LET cause most damage thru _____ (indirect or direct) effect and is therefore _______ (repairable or irrepairable)?
High energy LET are ____ (more or less) destructive that low LET radiation?
Low LET x-rays have a ____ (low or hight) probability of interacting with DNA?
OER is less with ___ (low or high) LET radiation?
OER is higher with ___ (low or high) LET radiation?
When the x-ray photon strikes the DNA molecule directly, is this a direct or indirect effect?
When the photon strikes a water molecule and creates an ion pair, this is called?
Radiolysis of water
List 2 types of free radicals that result from radiolysis of water
When the x-ray photon strikes a water molecule which then produces a free radical which then strikes the DNA this is called? (direct or indirect?)
Point mutation commonly occurs with ___ (low or high) LET
What is the main factor for the target theory?
DNA is the target.
the DNA molecule is hit and inactivates the cell which then will most likely die
If you hit the DNA, something is going to happen
When cells die without attempting cell division is called?
When cell death occurs after cell division, this is called?
When mitosis occurs after missing a division cycle, this is called?
What is the lethal doese for humans?
300-400 rads; 3-4 grays
The lethal dose is expressed as LD _/_? What does the first number represent and what does the second number represent?
The first number is percentage of effect (death in people)
The second number is how many days for the effect to occur
Radiation protection uses a linear _______ curve. Non-threshold or threshold?
Any radiation has the potential for problems
Non-stochastic effects are based on a ______ curve. non-threshold or threshold? They are also called? Deterministic or probabilistic?
Nausea, fatigue, erythemia, and epilation are types of early non-stochastic, late non-stochastic, early stochastic, or late stochastic? What are these symptoms classified as?
ARS-acute radiation syndromes
What are the three stages of ARS?
Prodromal (flu-like symtoms)
Latent (symptoms will resolve or be dormant)
Manifest (present with many symptoms. You got problems)
What are three types of ARS?
Cerebrovascular-Up to 5000 rads. Death in 2-3 days
Cataracts, fibrosis, organ atrophy, and decreased fertility are types of early non-stochastic, late non-stochastic, early stochastic, or late stochastic?
Cancer and genetic defects are types of early non-stochastic, late non-stochastic, early stochastic, or late stochastic?
Stochastic effects are based on a ______ curve. Non-threshold or threshold? They are also called? Deterministic or probabilistic?
Radiation within 10 days of pregnancy will result in?
The embryo is most sensitive during organogenesis which is from _ weeks to _ weeks. This will result in an embryologic effect.
2 weeks to 8 weeks
The occupational MPD is __ mSv, __ rem, __ mrem annually.
The pregnancy MPD is __ mSv, __rem, __ mrem monthly.
The pregnancy MPD for the entire pregnancy is __ mSv, __ rem, __ mrem.
The public MPD is __ mSv, __rem, __ mrem.
The educational MPD is __ mSv, __rem, __ mrem.
Same as the public MPD
Radiation hormesis is?
The potential that small radiation exposure is actually beneficial
Collimator and light field is +/- __% of the SID