Ch 26 Digital Fluoroscopy Flashcards
the difference bb/w conventional fluoroscopy and digital fluoroscopy is:
the nature of the image and the manner in which it is digitized
the advantages of DR over conventional are:
the speed of getting the image and the post processing to enhance image contrast
pixel size=
image intensifier size / matrix
during DF tube current is measured in _____ and functions in the ______ mode; images are obtained by _____
hundreds of mA and functions in the radiographic mode; images are obtained by pulsing the beam called pulse-progressive fluoroscopy
interrogation time:
the time it takes to switch the tube on and it reach the selected kVp and mA
extinction time:
the time it takes to switch the tube off (less than 1 ms)
duty cycle:
the time when the tube is energized
a major change from conventional to DF is:
the use of a CCD instead of a TV camera tube
the sensitive component to a CCD is:
the layer of silicon
the CCD is mounted on _____ and coupled through ____
the output phosphor of the I.I. and coupled through fiber optics
ABS:
automatice brightness stabilization
the spatial resolution of a CCD is determined by:
physical size and pixel count
the CCD has _____ and _______ than a TV camera tube
greater sensitivity to light and lower level of electronic noise
higher signal-to-nosie ratio (SNR) equals:
better contrast resolution and lower patient dose
