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5 Cards in this Set
- Front
- Back
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Purpose of Grids
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Absorb (secondary) scatter radiation, thereby improving image contrast
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Grid Materials
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Radiopaque strips (usually lead)
Radiolucent interspace material (aluminum or plastic fiber) |
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Grid Ratio
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= height of lead strip/distance between strips
High grid ratio is best at removing scatter (though it requires greater accuracy and higher patient dose) |
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Grid Frequency
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# of lead strips/inch or cm
(60-200 lines/in normal) High frequency shows less grid lines High frequency needs higher technique/patient dose |
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Lead content
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Determined by grid ratio and frequency
As lead content increases, better at removing scatter, better contrast High lead content: high grid ratio and low frequency |
