Ch. 1 & 11 Flashcards
(106 cards)
electromagnetic energy is also known as what
radiation
output of radiographic unit’s radiation measurement in air
coulomb/kilogram (c/kg)
we use these instead of parallel grids to prevent grid cutoff due to beam divergence
focused grids
grid that can be used on both 40” and 72” SID
dual focused grid
what do filters do
filter out low energy photons which decreases patient dose
x-ray tubes operated above 70 kVp are required a filtration of what
at least 2.5 mm aluminum
particulate matter capable of ionizing an atom
alpha and beta particles
radiation that is capable of removing an orbital electron from one of the subjects atom
ionizing radiation
what are all the names for kVp
strength, penetration, quality, potential difference, electric potential
who initially brought to light the dangers of x-ray and who else was the first casualty
Thomas Edison; Clarence Dally
what does CT stand for
computed tomography
what is penumbra
blurring of the edges (unsharpness)
direct square law is also called
maintenance law
what is the speed of light
3x10^8 m/s
how is the magnification factor (MF) calculated
SID/SOD=MF
to maintain optimal exposure while changing the SID you use
direct square law/maintenance law
increasing kVp does what to patient dose
decreases patient dose by increasing transmission and decreasing absoption
decreasing collimation does what to scatter and contrast
increases scatter and lowers contrast
using a grid does what to contrast
increases contrast by eliminating scatter
the head and neck of the anode are made of what
molybdenum
what do you do if your image is under exposed and under penetrated
increase kVp by 15%
what is the negative side of the tube head called
cathode
insufficient mAs will result in what
increased quantum noise (grainy image)
what does a grainy image indicate
not enough mAs