fluoroscopy Flashcards
who is Clarence Dally? Why is he important to the history of fluoroscopy?
Edison’s assistant; died of excess radiation dose
5 main parts of an image intensifier
input phosphor
photocathode
electrostatic focusing lenses
accelerating anode
output phosphor
what does the input phosphor do?
converts energy to visible light
what does the photocathode do?
converts light stimulus to emitted electrons
in an image intensifier, the input phosphor and the photocathode (are/are not) bonded together
are
electrostatic focusing lenses are ________ in charge
negative
electrostatic focusing lenses ______________________
repel the electron stream
the accelerating anode in an image intensifier is _________ and maintains ________
positively charged; constant 25 kV
what does the output phosphor do?
produce light in response to electron interact
what is flux gain?
of output light photons/number of input x-ray photons
what is minification gain?
(diameter of input phosphor/diameter of output phosphor)²
what is brightness gain?
minification gain x flux gain
what is conversion factor?
output phosphor illumination/input exposure rate
Automatic brightness control (ABC) will automatically adjust _________________
kVp, mA, or both
Magnification mode tightens _________ of electron stream and shifts focal point ___________ output phosphor. This is done by ________________ to the electrostatic focusing lenses
diameter, father from, increasing voltage
