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

110 Unit 3 Sect B

QuestionAnswer
attenuation beam energy reduced when passing through tissue/material
contrast difference between adjacent densities
density degree of darkening of film
distortion misrepresentation of true size of object
dynamic with motion
half value layer filtration needed to reduce beam to half its original value
intensifying screen luminescent crystals inside cassette to expose film
Inverse square law formula desribing relationship betwwen intensity and distance
Kilovoltage peak (kVp) measure of electrical pressure, controls quality/quantity of photons in tube
latent image invisible image after exposure but before processing
Milliampere Second (mAs) milliamperage X seconds, controls quantity of photons produced in tube, exposure and density
penetrating ability beam ability to pass through object, controlled by kVp
penumbra fuzzy border
photon particle of radiant energy
Positive Beam Limitation (PBL) automatic collimation
primary radiation beam before hitting object
radiolucent permitting xray passage with little attenuation
radiopaque not easily penetrable by xrays
recorded detail representaion of objects true borders
relative speed speed of film and intensifying screen, slow film, sharper image and more radiation
remnant radiation radiation after beam exits object
resolution measurement of recorded detail on radiograph, aka sharpness of detail, definition
scatter radiation photon interacts with matter, goes in different direction, radiation produced
static unmoving
umbra true border of object as imaged
photographic qualities density and contrast
geometric qualities recorded detail and distortion
mAs formula mA x time = mAs
Exposure/density influencing factors patient factors, kVp, distance, beam modification, grids, film/screen combinations, processing
15% rule increase kVp 15% will double exposuredecrease kVp 15% will halve exposure
15% rule with no change in exposure increase kVp 15% and halve mAsdecrease kVp 15% and double mAs
inverse square law definition intensity of beam is inversely proportional to the square of the distance from the source
inverse square law formula I1/I2=D1squared/D2squared
inverse square law tip halve the distance, X intensity by 4
exposure maintenance formula mAs1/mAs2 = D1squared/D2squared
primary beam modification modified beam before entering patient
scale of contrast range of gray tones; few is high contrast, short scale and vica versa
Influencing factors of contrast patient factors, mAs, beam modification, film/screen combinations, contrast media, processing
factors affecting recorded detail motion, object unsharpness, focal spot size, SID, OID, and material unsharpness
SID greater SID better recorded detail
OID greater OID, decreased sharpness
size distortion magnification
shape distortion true distortion
shape distortion controlling factors alignment of beam, part and IR
spot imaging flouroscopy unit changes to radiographic mode
anode positive electode, target, method to accelerate
cathode negative electrode, filament
rotor exposure switch device that begins the exposure
ALARA (radiation exposure) as low as reasonably acheivable
Classic Coherent scattering low energy photon absorbed and released with only a change in direction
Compton effect scattering high energy photon strikes end removes electron from shell, remaining energy released as scatter photon, most harmful to RT
Curie (Ci), Becquerel (Bq) measures the rate a radionuclide decays, 1Ci=3.7 x 10(to the tenth)Bq
SI Units metric radiation measurement developed in 1948
Kilelectron Volt (keV) equal to 1000 electron volts
pair production interaction between matter and photon having 1.02 million electron volts, producing positron and negatron
photoelectric effect photon strikes inner shell electron ejecting it and absorbing photons energy, most harmful to patient
vaccuum tube housing
radiation forms of energy emitted and transferred through matter
Radiation Absorbed Dose(rad), Gray(Gy) units measure amount of energy absorbed 1 Gy=100 rads; Gy is SI units
Roentgen (R) measures ionization in air
Radiation equivalent man (rem), Sievert (Sv) measures biologic response of exposed individuals to same quantity of differing radiations 1Sv=100rem; Sv is SI unit;1rad=1rem
Somatic cell all of body's cells except germ cells
xray electromagnetic radiation traveling at the speed of light with the ability to penetrate matter
ionizind radiation capable of creating ions by removing orbital electrons with which it reacts
Natural background radiation uranium, radon; we get approx. 295 mrem/yr
man made radiation nuclear power, xrays, ect. we get approx. 65mrem/yr
properties of xrays penetrating electromagnetic waves, heterogenous(many energies), polyenergetic, travels in straight lines, can't be focused, electronically neutral, produce scatter, ionize gasses, cause biological change
absorbtion transfers energy
transmission xrays pass through matter with no reaction
photodisintegration occurs in nuclear industry; energy interacts directly with nucleus, causes excitement, emits nuclear fragment
Created by: sandonblaise