Digital imaging week 3 terms Flashcards
adjusting brightness and contrast
windowing
what controls the contrast
window width
what type of relationship between window width and contrast
inverse relationship
what controls the brightness (density)
window level
what type of relationship between window level and density
direct relationship
brightness values of adjacent pixels can be brought closer together
smoothing
all or part of image can be magnified
magnification
brightness can be increased along edge to increase visibility
Edge enhancement
removal of background anatomy to allow visualization of contrast enhanced anatomy
subtraction
dark and light pixel values are reversed
image reversal
adding text to an image
annotation
highly complex mathematical formulas applied to a data set for digital imaging
algorithm
representative of the number of shades of gray that can be demonstrated by each pixel, determined by the manufacturer based on the imaging procedures the equipment is required for, most common available are 10, 12 & 16
Bit-depth
the intensity of light that represents the individual pixels in the image on the monitor
Brightness
solid state device that converts visible light photons the electrons
CCD charge coupled device
a method of acquiring radiographic images digitally;
computed radiography (CR)
CR’s main components
PIP
IP reader
tech workstation
an imaging system’s ability to distinguish between similar tissues
contrast resolution
a method of acquiring radiographic images digitally; DR detector replaces the film screen system and the CR IP as the image receptor
Digital Radiography
series of “boxes” that give form to the image
Display matrix
pixel size of the monitor related to the display matrix
display pixel size
post processing technique that increases brightness along the edges of structures on an image to increase the visibility of the edges
edge enhancement
numeric value that is representative of the exposure the IR received in digital radiography
exposure index
range of exposure factors that will produce an acceptable image
exposure latitude
the image matrix size provided by digital x-ray imaging systems
field of view
computer system designed to support and integrate the operations of the entire hospital
hospital information system
random disturbance that obscures or reduces clarity in a radiographic image, grainy or mottled appearance
noise
picture element, an individual component of a matrix
pixel
changing or enhancing the electronic image in order to view it from a different perspective or improve its diagnostic quality
post processing
computer system that supports the operations of a radiology department
(RIS) Radiology Information System
random access memory (temporary)
RAM
read only memory (permanent)
ROM
a post processing technique that adjusts brightness values of adjacent pixels closer together
smoothing
the electronic transmission of diagnostic imaging studies from one location to another for the purposes of interpretation and/or consultation
Telaradiology
the user adjusting the window level and window width (image contrast and brightness)
windowing
controls the brightness of a digital image
window level
controls the range of gray levels of an image
Window width
final phase of image processing in digital during which the computer compares the image histogram with the selected LUT and applies to the raw data to align the image histogram with the LUT
Auto rescaling
post processing that adds a black background around the exposure field providing a perceived enhancement of image contrast
shuttering
