<prompt> CT dose index, True is:By reducing KVP by 50 radiation dose is reduced to halfIn pediatric patients dose should be reducedCT dose index is not useful for control exposure in multi-slice CTKV has no control over CT dose index  <response>: B. i.e. In pediatrics patient dose should be reduced Because ionizing radiation causes more biological effect in children, it is impoant to adapt CT technical parameters to minimize radiation doseQ. CT Dose index CTDI - Is most common parmeter to estimate and minimize patient dose in CTQ. - Integrates the dose delivered both within beyond the scan volume. Factors that influence radiation dose from CT: KVp Kilovoltage - has nonlinear relationship with radiation doseQ - An t in 120-130 KVp can double radiation doseQ. Tube current mAs - has linear relationship with radiation dose - I mAs by 50 : ies radiation twice Pitch Slice - is inversely propoional to radiation thicknessTable speed dose. 