Use of CTDI in comparative dosimetry
Protocol nCTDIw mAs CTDIw Pitch CTDIvol L DLP
mGy / mAs used mGy mGy cm mGy.cm
A 0.10 300 30 1 30 10 300
B 0.15 200 30 1.5 20 15 300
C 0.11 280 33 2 17 15 255
CTDIw = average absorbed dose in scan plane (x-y)
CTDIvol = average absorbed dose in scan plane and z-axis (x-y-z)
DLP = comparison of risk (‘ED’ w/o organ sensitivity)
DLP = CTDIvol ? protocol length (See CEC definitions for specific equations)