Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
Know
remaining cards
Save
0:01
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
Retries:
restart all cards
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

RADT 465: radbio/saf

BR: rad bio& physics

QuestionAnswer
this can be discribed as wave like fluctuations of electric and magnetic fileds electromagnetic radiation
refers to the distance between two consecutive wave crests wavelenght
refers to the number of cycles per second frequency
what is frequencys unit of measurement hertz (Hz)
what is the velocity of electromagnetic radiations 3 x 10^8 m/s
some radiations are energetic enough to rearrange atoms in the materials through which they pass, and they can therefore be hazardous to living tissue. this is known as ionizing radiation
ionizing radiation has the potential to break apart electrically neutral atoms
___ photons are man-made infinitesimal bundles of energy that deposit some of their energy into matter as they travel through it. xray
what are the 2 PRODUCTION xrays Bremsstrahlung and characteristic
High speed electron is deflected from it path and the loss of kinetic energy is emitted in the form of an xray photon bremsstrahlung
Bremsstrahlung comprises what percentage of the primary xray beam 70-90
A high speed electron ejects a tungsten K-shell electron, leaving a k-shell vacancy. An electron from the L-shell fills the vacancy and emits a ray characteristic
When is the xray created in the bremsstrahlung the energy loss is given up in the form of an xray
K-characteristic xrays from a tungsten target xray tube have ____keV evergy 69
what are the 3 INTERACTION xrays Compton, photoelectric, coherent
The incoming (low-energy) photon releases all of its energy as it ejects an inner shell electron form the orbit photoelectric
The photoelectric effect is more likely to occur in absorbers having what high atomic number
what interaction significantly effects patient dose photoelectric
incoming (high energy) photon uses part of its energy to eject an outer shell electron; in doing so, the photon changes direction (scatters) but retains much of its original energy compton
what interaction do us technologists have to be concerned about compton
an incident photon that does not have enough energy to remove an inner shell electron, due to low binding energy, it is deflected and turned into scatter radiation coherent
relationships are those in which the response is directly proportional to the dose received, that is, id the dose is increased, the biologic response is increased linear/straight line
the effects are not proportional to the dose nonlinear
a dose must be received before a response can occur threshold
responses that are proportional to the radiation dose received only after some particular dose is received. linear, threshold
this effect occurs randomly and are "all or nothing" stochastic or probabilistic
no safe dose- even one photon can cause a response nonthreshold
is the SI unit of ionizing radiation absorbed in matter (absorbed dose) Air kerma (kinetic energy released in matter)
The quantity that measures risk to human tissue is termed effective dose (EfD)
the SI unit of effective dose to biologic tissue Sievert (Sv)
SI unit of radioactivity; it's symbol is Bq The Becquerel
he rate at which particulate or photon energy is transferred to the absorber. Because different kinds of radiation have different degrees of penetration in different materials, it is also a useful way of expressing the quality of the radiation LET
the amount of material necessary to decrease the intensity of the beam to one-half HVL
What 2 factors affect both the quality and the quantity of the primary beam? Kv & HVL
Why are muscle and nerve tissue insensitive to radiation? they do not divide; remember, the most sensitive tissues to radiation are tissues that are constantly dividing (mitosis) Epithelial cells
If the center photocell were selected for a lateral projection of the lumbar spine that was positioned with the spinous processes instead of the vertebral bodies centered to the grid, how would the resulting radiograph look? The image would be underexposed.
when you want to make an exposure longer, you would decrease... mA
A decrease in kilovoltage will result in a decrease in receptor exposure & a shorter-scale, or higher/increased, contrast.
risks have a threshold, are nonlinear, includes all early effects, and includes some late effects nonstochastic/deterministic
risks have no threshold, are linear, have genetic effets, cause cancer, and includes most late effects stochastic/propbabilistic
effect occurs when the ioniziing particle (an electron) interacts directly with the key molecule (DNA) or another critical enzyme or protein direct effect
radiation interaction with water; ionization water radiolysis
the more frequent occurring effect happens when ionization takes place away from the DNA molecule, in cellular water indirect effect
this effect creates free radicals indirect effect
small doses delivered over a long period of time produce a lesser effect (the greatest effect of irradiation will be observed if a large quantity of radiation is delivered in a short time to the whole body fractionation and protraction
the greater amount of what makes tissues greater in their radiosensitivity oxygen // aerobic
during the first trimester, specifically the 2nd to 10th weeks of pregnancy what can appear skeletal and/or organ anomalies
fetal irradiation during the first 2 weeks of gestation can result in embryonic resorption or spontaneous abortion
what are 3 ways to reduce risk to recently fertilized ovum elective scheduling/10 day rule, patient questionnaire, posting (posters)
the average annual gonadal dose to the population of childbearing age is estimated to be 0.2 mSv (20mrem)
____ effects are described as being early or late somatic effects
are manifested within minutes, hours, days, or weeks of irradiation early somatic effects
appear years after initial exposure and are caused by low, chronic exposures late somatic effects
Acute radiation syndrome (3) hematopietic, gastrointestinal, central nervous system
this ARS can cause nausea, vomiting, diarrhea, decreased blood count, infection and hemorrhage hematopoietic
this ARS syndrome generally occurs between 10 and 100 Gy (1000 and 10,000 rad) & causes severe damage to the stem cells lining, resulting in nausea, vomiting, diarrhea, blood changes, and hemorrhage; death occurs within 2 weeks GI syndrome
this ARS syndrome causes collapse of the circulatory system, as well as increased pressure in the crnial vault, vasculitis, atazia and shock. death occurs in 3 days CNS
what are the 4 stages of acute radiation syndorme prodromal (few hours following radiation), latent (symptoms fade), manifest illness (symptoms return), recovery or death
occupational: annual dose 50 mSI (5 rem)
occupational: lens of the eye 150 mSI (15rem)
occupational: skin, hands and feet 500 mSI (50 rem)
occupational: cumulative radiation 10x age for mSI or 1 x age for rem
Public: anual dose 5 mSI (0.5rem)
Public: lens of the eyes, skin, hands and feet 50 mSI (5rem)
minimum lead equivalent: lead aprons 0.5 mm
minimum lead equivalent: gloves 0.25 mm
minimum lead equivalent: thyroid shield 0.5 mm
minimum lead equivalent: glasses 0.35 mm
minimum lead equivalent: bucky slot covers 0.25 mm
minimum lead equivalent: fluoroscopy drapes 0.25 mm
minimum lead equivalent: clear lead plastic overhead protective barrier 0.5 mm
minimum thickness of filtration requirement for operating kv: below 50 0.5 mm
minimum thickness of filtration requirement for operating kv: 50 - 70 1.5 mm
minimum thickness of filtration requirement for operating kv: above 70 2.5 mm
Embryo: radiation per month 0.5 mSV (0.05 rem)
Embryo: entire gestation 5 mSV (0.5 rem)
min SSD fixed fluoro unit 15 in
min SSD mobile fluoro unit 12 in
cumulative fluoro time every 5 mins
primary barrier 1/16 in
secondary barrier 1/32 in
Created by: 2024767030873700