Expected headings
"Image quality"
"Dose"
"The ability to reduce mAs by a fifth-power relation is more than adequate to balance the second to third power direct effect of increasing kVp on photon quantity. The difference is related to how the probability of energy absorption in various biologic tissues declines dramatically over the range of photon energies used for diagnostic imaging 9. Thus, absorbed dose can be reduced while keeping the image receptor exposure constant by choosing a higher kVp and lower mAs. As this reduction is achieved with higher energy photons, however, the tradeoff is lower image contrast. Lower kVp techniques may be employed at lower dose when contrast is more important (e.g. CT angiography of the abdomen 10) or when noise related to attenuation is less of a problem (e.g. children 11)."