15% Rule for Radiology
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Contrast2c1525rule2candmAsreciprocity1.pptxContrast and 15% rule
This image is the base line image and was taken at 110 KVP and 2.5 mAs.
Contrast and 15% rule
This image was taken at 126 KVP and 2.5 mAs and shows that by raising KVP by 15% we decreased contrast and increased density.
Contrast and 15% rule
This image was taken at 126 KVP and 1.25 mAs and shows that by raising KVP by 15% and halving mAs, we decreased contrast while maintaining density. This proves the 15% rule to maintain density is true.
Contrast and 15% rule
This image was taken at 94 KVP and 2.5 mAs and shows that by decreasing KVP by 15% we increased contrast and decreased density.
Contrast and 15% rule
This image was taken at 94 KVP and 5 mAs and shows that by lowering KVP by 15% and doubling mAs, we increased contrast while maintaining density. This further proves the 15% rule to maintain density is true.
mAs Reciprocity
This image is the base line image and was taken at 50 KVP and 3.3 mAs with mA at 100 and time at 0.033 seconds.
mAs Reciprocity
This image was taken at 50 KVP and 3.3 mAs with mA at 50 and time at 0.067 seconds. This proves mAs reciprocity in that you can halve your mA and double your time and still have the same mAs.
mAs Reciprocity
This image was taken at 50 KVP and 3.3 mAs with mA at 200 and time at 0.017 seconds. This proves mAs reciprocity in that you can double your mA and halve your time and still have the same mAs.
