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Artifacts
Diagnostic Imaging - VTT 224
Question | Answer |
---|---|
What is an artifact? | Any unwanted radiograph density that forms a blemish on the film. |
What is fogging? | An overall grey appearance. The film was either exposed to excessive scatter radiation or exposed to prolonged safe light, or excessive heat during storage. |
How are black crescents or lines formed? | Rough handling of the film, creased or scratched. Fingerprint smudge from too much pressure. |
How is a black irregular border caused? | By light exposure while still in the box or film bin. |
Static electricity discharge may appear as...? | A tree or lightning strike. |
How are film guide scratches caused? | The film was fed crooked into the processor, and jammed when it was caught in the drive gears. |
What is a kissing artifact? | When more than one film is fed into the processor at once, only one side of the emulsion will be completely processed. |
How are roller artifacts caused? | Developer being on the entrance rollers, or pulling a film out of the processor feed tray. |
What are white areas? | Foreign materials (artifacts or dirt) that exist between the film and the screen, or chemical spills that cause permanent damage to the phosphor layer. |
Overdeveloped film | Increased density with poor contrast. Caused by being in developer too long, or chemicals too hot. |
Underdeveloped film | Decreased density with poor contrast. Caused by chemicals being too cold or old chemicals. |
Uneven development | Caused by unstirred, settled chemicals or light exposure during developing or uneven chemical levels. |
Identical black spots on two films | Caused by film sticking to each other in the fixer. |
A brown image is caused by...? | Old developer or if the wash tank is not properly filled, the fixer is retained on the the emulsion. |
What is a run back artifact? | When excess chemicals remain, it creates a streaky artifact. |
Processor water marks are...? | Water spots on the film. |
What is Sante's Rule? | 2 x (tissue thickness in cm) + FFD + Grid factor = kVp |
When developing a technique chart, start with....? | Determining a baseline mAs. |