measures how quickly in space, an object changes 7 p) is expressed in line pair per millimeter (lp/mm).
The ability to distinguish one soft tissue from another without regard for size or shape.
detective quantum efficiency
how efficient a system converts the x-ray input signal into a useful output image
modulation transfer function
is the ratio of the recorded contrast of an image to the real objects subject contrast; ratio of image to object as a function of spatial frequency.
k-shell binding energy
The energy that holds a K-shell electron in its orbit around the nucleus
bar pattern test tool
A test tool consisting of lead bars and equal interspace of different sizes. Used to evaluate imaging system spatial resolution.
contrast detail curve
A graphical method of displaying the spatial resolution and contrast resolution of an imaging system. Used to compare various imaging systems and changes in their display.
The gray scale. p) The number of shades of gray that can be rendered by an imaging system.
Digital Mammography Imaging Screening Trial
Manipulation of digital data to improve image contrast and other features; allows visualization of all shades of gray.
an imaging system with higher spatial frequency has better ___________ ____________; digital imaging is limited by pixel size.
imaging system spatial frequency at _______
image noise limits _____________ ______________
by system MTF
How is image detail determined?
noise or SNR
What limits contrast resolution?
is a black line & an equal interspace space (white line) higher spatial frequency = high spatial resolution.
What value of modulation transfer function (MTF) is often used by imaging system vendors to describe their imaging system?
As an object gets smaller, which of the following gets bigger?
ability to image rate of change
Modulation in imaging is a term that is best described as the:
higher detective quantum efficiency (DQE)
Why does radiography have a higher modulation transfer function at low spatial frequencies than does screen-film imaging?
low spatial frequency
Objects high spatial frequency are more difficult to image than those with _______ _____________ _______________.
contrast, high spatial frequencies
at low spatial frequencies, the _________ of the object is preserved, but at _________ ___________ ______________, contrast is lost; this limits the spatial resolution of the imaging system.
Ratio of magnitude of the analytical signal to the magnitude of the background noise signal.
the signal in a radiographic image is that portion of the _________ __________x-rays that represents anatomy.
the __________ represents the difference between those x-rays transmitted to the image receptor and those absorbed _____________.