Term
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Definition
| -controls contrast, affects quality and quantity |
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Term
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Definition
| Grid ratio-Increasing grid ratio produces more scatter absorption which results in increased contrast. |
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Term
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Definition
| Intensifying screens increase contrast. Film exposed to light from IS decrease contrast. |
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Term
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Definition
| Developer time/temperature- Increasing film developer time, temperature or replenishment rate from optimal range will increase chemical fog , which decreases contrast. |
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Term
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Definition
| If mAs is too high, contrast decreases. If mAs is too low, contrast increases. |
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Term
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Definition
| increase in collimation (smaller field size) irradiates less tissue, reduces scatter and therefore increases contrast. |
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Term
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Definition
Fifteen% Rule: 15% increase in kVp=1/2 mAs
Five % Rule: 5% increase=30% reduction in mAs |
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Term
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Definition
| Contrast controlled by window width (gray scale). Window width increased-contrast decreased. (Inverse). |
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Term
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Definition
| degree of difference in densities. |
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Term
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Definition
| - Primary Controlling factor. Increasing mAs increases exposure which increases density (and vice versa). mAs must be changed by at least 30% to produce a visible difference in density. |
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Term
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Definition
| Increasing kVp increases the quantity of radiation the energy of the beam and the strength of the electrons and therefore increases density. kVp must be changed by at least 4% to produce a visible change in density. |
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Term
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Definition
| 15% increase in kVp=1/2 mAs, 15% decrease in kVp=2x mAs |
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Term
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Definition
| 15% increase in kVp=2x mAs |
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Term
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Definition
| 15% decrease in kVp=1/2 mAs |
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Term
| Black lungs, white bones indicates high or low subject contrast? |
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Definition
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Term
| Abdomen w/ gray images, no clear or black or white indicates high or low subject contrast? |
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Definition
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Term
| Does x-ray quality remain fixed with mAs? |
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Definition
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Term
| Only ____ is affected by changes in mAs |
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Definition
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Term
| Only ____ is affected by changes in mAs |
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Definition
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Term
| Does distance have an effect on quality? |
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Definition
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Term
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Definition
| OD. An inc in dist=dec in density |
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