Optical density, artifacts
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| When only soft tissue is beng imaged, __ kVp and __ mAs are used. | Low, High
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| ___ kVp and __ mAs results in an image with satisfactory contrast and low patient radiation exposure. | High, low
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| Radiolucent tissue appears ___ on radiographs. | Black
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| Radiopaque tissue appears __ on radiographs. | White
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| Destructive pathology causes tissue to appear __. | Radiolucent
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| Constructive pathology causes tissue to appear __. | Radiopaque
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| What is optical density? | Degree of blackening of the finished radiograph.
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| In OD, black is has an OD of what number? | 4 or greater
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| In OD, clear has an OD of what number? | Less than 0.2
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| OD is controlled by what 2 factors? | mAs and SID
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| In order to produce a visible change in OD, mAs must be changed by __%. | 30%
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| kVp must be change by __% to produce a perceptible change in OD. | 4%
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| A __% increase in kVp accompanied by a half reduction in mAs results in the same OD. | 15%
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| The simplest method for increasing or decreasing OD on an x-ray is to increase or decrease __. | mAs
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| High kVp produces? | LONG scale, LOW contrast, LESS contrast
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| Low kVp produces? | SHORT scale, HIGH contrast, MORE contrast
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| Detail is controlled by? | Focal-spot size
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| What are the three classes of artifacts? | Processing, Exposure and Handling
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| Pi lines, dichroic stains and chemical fog are examples of what type of artifact? | Processing artifacts
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| Motion, poor screen contact and improper grid position are examples of what type of artifact? | Exposure artifacts
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| Kink marks, radiation fog and scratches are examples of what type of artifact? | Handing and storage artifacts
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| What are two types of roller marks? | Guide-shoe marks and Pi lines.
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| What is the cause of dichroic stains? | Improper squeezing of processing chemicals from film
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| What is the cause of guide-shoe marks? | Improper position or springing of guide shoes in turn-around assembly.
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| What is the cause of pi lines? | Dirt or chemical stains on rollers
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| T/F: Dichroic stain is a type of chemical fog. | True
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| T/F: Processing artifacts in digital radiography are different from those with screen-film because the method of producing the image is electronic instead of chemical. | True
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| Name several handling and storage artifacts. | Fog, kink marks, crown
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| What causes pressure marks? | Improperly or roughly handled film
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| What causes fog? | High temperature or humidity
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| What are the 3 types of static artifacts? | Crown, Tree and Smudge
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