RAD 350 Chapter 19 Image Artifacts
Artifact = something that shows on the image that is NOT actually a part of the body being imaged.
Can come from MANY things; Improper patient preparation – i.e. leaving articles of clothing or jewelry on; art on clothing – like painted items or decorative designs (check out the little heart on the panties on a pelvis radiograph in Chad’s office); bra clips, snaps and underwire; zippers; one of the craziest I’ve seen was when a guy took out his “loops” from his ear – unbeknown to me he placed them in his T-shirt pocket – his sinus series looked GREAT, but the CXR looked like he had SIX NIPPLE RINGS all in ONE nipple on his chest image!
Other artifacts can be caused by MOTION – either the patient or the equipment moving – perhaps with the I.R./film NOT secured in the reciprocating bucky – the I.R./film moves; grid cut off; wrong film loaded into a cassette; foreign objects inside the cassette (dust, dirt, paper, etc.,); double exposure is also considered an artifact.
Processor induced/handling artifacts:
Guide shoe lines (leading and trailing edge of the film)
Pi lines (3/14” across the film from left to right or right to left)
Fog (chemical, light, etc)
“Curtain effect” – caused by chemical rundown (also called “DICHRONIC STAIN”)
Various roller induced artifacts: uneven squeegee of chemicals by the rollers; “blotches” caused by separating portions of the roller material, etc.
Improper processing of the image: chemical caused – “exhausted/contaminated” developer; improper replenishment (too much or too little); improper fixing (milky look) due to not “clearing” the film of unexposed/undeveloped silver halide/bromide crystals from the emulsion; “greasy appearance” due to improper or NO washing (fixer will turn brown over time = called fixer retention).
Static artifacts (usually with changes in humidity and handling the film) – “tree static” and handling “kink” (quarter moon shaped) are all common.