Term
| How is X-ray intensity measured? |
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Definition
| Intensity is measured in Roentgens (R or MGy a) or milliroentgens (mR) and is termed the x-ray quantity. |
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Term
| What is a roentgen (mGy a)? |
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Definition
| A measure of the number of ion pairs produced in air by a quantity of x-rays. |
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Term
| What are some other names for X-ray intensity? |
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Definition
| X-ray quantity, radiation exposure, X-ray quantity. |
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Term
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Definition
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Term
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Definition
| The number of x-rays in the useful beam. |
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Term
| What are the factors affecting x-ray quantity? |
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Definition
| Milliampere-seconds (mAs), Kilovolt Peak (kVp), and Distance. |
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Term
| Milliampere-seconds (mAs) |
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Definition
| X-ray quantity is directly proportional to mAs. |
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Term
| mAs x-ray quantity formula |
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Definition
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Term
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Definition
| X-ray quantity varies approximately as the square of the change in kilovolt peak (kVp). |
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Term
| kVp x-ray quantity formula |
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Definition
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Term
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Definition
| X-ray quantity varies inversely with the square of the distance from the target (the inverse square law). |
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Term
| Distance x-ray quantity formula |
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Definition
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Term
| X-ray exposure of a patient can be estimated to a reasonable approximation with the use of what equation? |
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Definition
| x-ray quantity (mR) = k (mAs) (kVp)2/D2 |
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Term
| When the mAs is increased, x-ray quantity: |
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Definition
| Incrreases proportionately. |
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Term
| When the kVp is increased, x-ray quantity: |
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Definition
| Increases in proportion to kVp2. |
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Term
| When distance is increased, x-ray quantity at that distance: |
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Definition
| Decreases in proportion to distance squared. |
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Term
| When x-ray tube filtration is increased, x-ray quantity: |
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Definition
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Term
| In general, x-ray quantity will increase with a/an: |
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Definition
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Term
| X-ray quantity is usually measured as which of the following? |
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Definition
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Term
| X-ray quantity can be measured in which of the following? |
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Definition
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Term
| Another meaning of "x-ray quantity" is x-ray: |
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Definition
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Term
| Factors affecting x-ray quantity |
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Definition
| Filtration, kVp, mA, and Time |
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Term
| To maintain a constant optical density, what percentage increase in kVp should be accompanied by a reduction of one half in mAs? |
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Definition
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Term
| An extremity radiograph requires 5 mAs and results in an exposure of 18 mR. What will be the exposure if the technique is changed to 7 mAs? |
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Definition
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Term
| An abdominal view is taken at 82 kVp and results in a patient exposure of 132 mR. To improve contrast, the kVp is reduced to 74 with no change in mAs. What is the new patient exposure? |
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Definition
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Term
| A portable chest x-ray is taken at 90 cm SID, and the patient exposwure is 28 mR. What will the eposure be if the distance s increased to 180 cm and there is no accompanying technique change? |
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Definition
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Term
| The output intensity for an x-ray imaging system operated at 70 kVp/400 mA and 50 ms is 70 mR. If the mA selector is changed to 600 mA and the exposure time is increased to 80 ms, what will be the output intensity? |
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Definition
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