1.52k likes | 5.88k Views
Image Artifacts. Bushong Ch. 17 & 31 Carter Ch. 7. ARTIFACTS: AN UNWANTED DENSITY ON THE FILM. http://www.xray2000.co.uk/. Artifacts. Any irregularity on an image that is not caused by proper shadowing of tissue by the primary x-ray beam.
E N D
Image Artifacts Bushong Ch. 17 & 31 Carter Ch. 7
ARTIFACTS:AN UNWANTED DENSITYON THE FILM http://www.xray2000.co.uk/
Artifacts • Any irregularity on an image that is not caused by proper shadowing of tissue by the primary x-ray beam. • Are undesirable optical densities or blemishes on a radiograph. • Can be very interesting at times. You become the detective, what caused that?
Exposure Artifacts • Exposure artifacts are generally associated with the manner in which the radiographer conducts the examination • Incorrect screen-film match, poor screen-film contact, warped cassettes, improper positioning of the grid, Improper patient position, patient motion, double exposure, and incorrect radiographic technique • Largest area for repeat exposures
ExposureArtifacts • Usually easy to detect And correct
Double Exposure 2 exposures made on top of each other – exposure artifact
Lack of contact between film and cassette can cause “blurring” of the image
? Hands over upper abdomen
Dust in imaging plate can cause white marks on image – Both in film/screen and computed radiography
What do you See? 2 exposures
CR plate tube side down
PROCESSING ARTIFACTS • Most often caused by pressure. Pressure artifacts increase OD • Scratches or scrapes remove emulsion appear as low OD • Roller Marks, Pi lines, Dirty rollers, Chemical fog
Guide shoe marks Improperly placed Turnaround assembly
Pi Lines scratches
Handling & Storage Artifacts • Image fog – temperature, humidity, radiation, light • Pressure marks – film being stacked • Kink marks • Static • Hypo Retention
Discolored film due to hypo (fixer) retention. Chemicals not washed off – over time will turn film brown
Roller marks from film stuck – then pulled from processor
Image Receptor Artifacts • Debris on image receptor in DR can be confused with foreign bodies
Image Receptor Artifacts Line caused from dirt collected in a CR Reader
IR Artifact - Digital • Pixel Failure = CR & DR plates should last for thousands of exposures. Interpolation can be used to fix defects in a small area. • Ghosting artifacts = exposure to environmental radiation or incomplete erasure.
imaging plate was not fully erased before the chest examination was performed