Radiobiology COPY COPY COPY Flashcards
What is the linear theory?
That any amount of radiation is harmful.
Exposure to the entire body. (More detrimental than exposure to specific part.)
Whole body dose
Amount of exposure to the skin.
Skin entrance dose.
The skin entrance dose is always ______ than structures below the skin.
higher
The ______ the part, the ____ exposure due to absorption.
Deeper
less
The exposure of a specific organ of interest.
Organ dose
Exposure causing tissue damage of the exposed individual (early or late).
Somatic dose
What are the earliest effects of somatic dose?
Temporary erythema and hair loss.
Does somatic dose happen in diagnostic levels?
no
Exposure potentially causing damage to future generations of the exposed individual.
Genetic dose
Genetic dose attributed to _____ _____ of radiation exposure to gonads.
Low levels
Can genetic dose happen with diagnostic x-rays?
yes
What are the greatest effects of genetic dose?
Leukemia and mutations.
The amount of exposure that the unborn receives usually determined after the irradiation of a pregnant female.
Fetal dose
Fetal exposure up to _____ rads is not expel ted to cause any effects on the new born.
10 rads
Is 10 rads a usual dose in diagnostic filming?
NO, very unusual.
Actual dose a fetus receives can be calculated by whom?
Radiation physicist
Probability of harmful effect increases as dose increases.
Stochastic somatic effect
This will show long term effects of cancer and cataracts.
Stochastic somatic effect
KNOWN effects that increase with dose. Has a threshold at which effects are predictable.
Deterministic somatic (non-stochastic) effects.
Show short term effects such as erythema, infertility, blood forming damage, cataracts.
Deterministic somatic (non-stochastic) effects.
If exposed at a low level continuously, effects are reduced. This is called?
protraction
Non-continuous exposure to high dose reduces effect. This is called?
fractionation
Used in radiotherapy.
Protraction and fractionation
Used in radioactive implants.
protraction
The apparent beneficial effects of radiation.
Radiation hormesis
Theorized that small to moderate doses of radiation may reduce ____ and _________ and may prolong life.
Infections
Fatal malignancies
Theorized that small-moderate doses of radiation may also ___________ aiding in recovery of infections and other maladies.
Boost immunity
Radiation’s various effects from large acute exposures is called?
Acute radiation sickness (ARS)
How much radiation causes hematological syndrome?
200-1000 rads acute whole body
How much radiation causes gastrointestinal syndrome? Death will happen when?
1000-5000 rads
2 weeks
How much radiation causes CNS syndrome? How long to live?
5000 rads and over
Less than a week.
What are the four stages of ARS?
prodromal stage
Latent stage
Manifest stage
Healing or death
In ARS, what is the stage showing initial symptoms?
Prodromal stage
In ARS, this is the stage showing improvement of symptoms.
Latent stage
This is the stage of ARS where the symptoms return worse than before.
Manifest stage
This is the stage of ARS where you either live or die.
Healing or death
Acute whole body exposure that would kill 50% of the people in 60 days? Traditionally what?
LD 50/60
LD 50/30
LD 50/30 is how many rads for us?
300 rads
Lethal dose means a human has an LD ____ of ____rads with without medical intervention.
50/60
350
At ____ rads 100% would die without medical intervention.
600
Above ____ rads (__ Gy) all will die no matter what without medical intervention.
1000
10
