Module 11 - Week 17 - Imaging Errors and Artifacts Flashcards
What causes detector drop errors?
Mishandling or dropping wireless DR detectors.
How do you correct major detector drop errors?
Remove and replace the detector.
What is a common way to prevent detector drop errors?
Use protective cases and proper carrying techniques.
What type of contamination can damage DR detectors?
Fluid contamination.
How can backscatter errors be prevented?
Use tight collimation and place lead behind the detector.
What causes detector contamination artifacts?
Exposure to fluids or poor bagging.
What is the main cause of image lag?
Residual image signal from a prior high-dose or rapid exposure.
How is image lag corrected?
Perform offset calibration.
When should offset calibration be done?
After high-dose exposures or battery changes.
What causes flatfield calibration errors?
Ignoring manufacturer setup instructions.
How do you avoid calibration artifacts?
Ensure the detector is clear and flat during calibration.
What is the cause of automatic shuttering failure?
Poor collimation or excessive scatter.
How do you fix an automatic shuttering error?
Reshutter and reprocess the image.
What causes VOI (Value of Interest) errors?
Excessive field size or inclusion of raw radiation in histogram.
How is a VOI error corrected?
Reprocess the image with a corrected exposure field.
What causes receptor management errors in CR?
Background radiation on unused CR plates.
How do you prevent background fog on CR receptors?
Perform secondary erasure before use.
What happens if a receptor is placed backwards?
Receptor hardware appears on the image.
What is exposure clipping?
Saturation that results in loss of anatomy from overexposure.
What causes quantum mottle?
Underexposure resulting in a noisy, grainy image.
How do you correct exposure selection errors?
Adjust technical factors or AEC settings appropriately.
What causes partitioning errors?
Uneven split exposures or lack of 4-sided collimation.
How do you prevent histogram errors in partitioning?
Use even-numbered exposures with lead shielding and 4-sided collimation.
