25-3
the principal reason for image integration is to ______?
improve contrast resolution
a conventional radiograph is which of the following?
an analog image
during digital fluoroscopy, the_______?
the x-ray beam is pulsed
the combination of temporal subtraction and energy subtraction techniques is called_______?
hybrid subtraction
an advantage of digital imaging over conventional imaging is which of the following?
postprocessing
the maximum frame acquisition rate in digital fluoroscopy is about______?
30 frames per second
which of the following components found in digital fluoroscopy is not found in conventional fluoroscopy?
an analog-to-digital converter (ADC).
digital fluoroscopy is conducted in________?
in the progressive TV mode.
the minimum acceptable TV signal-to-noise ratio for digital fluoroscopy is________?
1000:1
a pixel is a _______?
two-dimensional digital image cell
the signal-to-noise ratio of a conventional TV camera tube is about______?
200:1
during digital fluoroscopy, the image receptor is which of the following?
the image-intensifier tube
how many video monitors are required for digital fluoroscopy?
2
interrogation time is_______?
is the time needed to switch on the x-ray tube
between the TV camera and the computer of a digital fluoroscopic system is a/an_______?
analog-to-digital converter.
compared with conventional fluoroscopy, digital fluoroscopy is conducted at________?
at much higher x-ray tube current
a principal advantage of digital fluoroscopy over conventional fluoroscopy for subtraction studies is_____?
contrast enhancement
the time-interval difference mode is best used for which of the following?
dynamic studies
a digital imaging system with a dynamic range of 210 will be able to reproduce how many shades of gray?
1024 shades of gray
the mask image is usually the_________?
first image
digital imaging systems can display images on a 1024 x 1024 matrix. how many pixels are present in such matrix?
1,048,576
the approximate pixel size for a 12-inch image intensifier tube and a 256-reconstruction matrix is______?
1.0 mm
reregistration of an image is used to do which of the following?
correct for motion
an advantage of temporal subtraction over energy subtraction angiography is________?
higher contrast at lower dose
energy subtraction is based on which of the following?
K-edge absorption