Flashcards in 2015 FALL FINAL!!!!!<3 Deck (86)
amount of metal that cuts intensity to half its initial output.
Half Value Layer (HVL)
*Thicker HVL=stronger beam
thick part of filter at thin part of anatomy
Cut SID in half
4x greater radiation intensity
1/4 radiation intensity
attenuation = _______ + _______
absorption + scatter
total absorption of incoming photon
xray gives up all of it's energy-knocks out an inner shell electron
released as electrons drop down to fill holes in shells.
White or Clear on radiograph
photoelectric effect/characteristic radiation
less than 30 kV (not in diagnostic)-TOO LOW
Modified scatter. Wray gives up some but not all of it's energy to knock out an outer shell electron.
Compton makes it's presence known through
Scatter is _____ on the radiograph
Are Pair Production and Photodisintegration in diagnostic?
No, too high
when xrays pass through without interacting with the atoms in the body. Shows up black
picture element that makes up the Matrix
larger matrix & greater number of pixels=
improved spatial resolution
Increasing pixel density and decreasing pixel pitch ________ spatial resolution
A. OD of 1=
B. OD of 2=
C. OD of 3=
COUNT THE ZEROS
Density (Screen Film)=
Recorded detail (Screen Film)=
Spatial Resolution (Digital)
Contrast (Screen Film)=
Grayscale/dynamic range (Digital)
utilizes a plate that is put in a reader to retrieve image
utilizes a digital plate or digital bucky that sends image directly to computer
Main advantage of CR/DR
Post processing (window and leveling)
1. overall darkness on radiograph
2. controlled by
To double density you must...
To cut density in half you must...
cut mAs in half
kVp controls _________