CR DR 8 Flashcards
any false visual feature on a medical image that simulates tissue or obscures tissue
artifact
interfere with diagnosis and must be avoided
Artifacts
In screen-film radiography, three classifications of artifacts occur—processing
processing, exposure, and handling or storage
digital radiography (DR), three classifications of artifacts
image receptor, software, and object.
Artifacts produced by ___can be corrected easily with proper cleaning unless
DUST
Dust on any section of the ____—cannot be corrected by the radiologic technologist and will require professional service.
CR optical path—mirrors and lenses
require replacement of the image receptor.
Scratches or a substantial malfunction of pixels
occurs because of incomplete erasure of a previous image on a CR IP.
ghost images
can contribute to ghost artifacts
Environmental radiation
a CR IP has not been used for ___ it should be erased again before use.
24 hours
There is no such thing as “_____” on these IPs.
radiation fatigue
the mathematical process of assigning a value to a dead pixel based on the recorded values of adjacent pixels.
Interpolation
With this irregular pattern, a pre-processing manipulation known as ___” is performed,
“flat-fielding
software correction that is performed to equalize the response of each pixel to a uniform x-ray beam.
flat- fielding
can be reconstructed to be exactly the same as the original image.
lossless mode
true or false: If a CR cassette has not been used for several days, it should be inserted into the reader for re-erasure.
true
Lossless compression
10% (10 : 1) to 50% (2 : 1) of
Lossy compression
to 100 : 1 or greater,
can be used on images in which exact measurement or fine detail is not required, such as video recordings that are to be replayed on a standard domestic television.
Lossy compression
