Dose in Diagnostic Radiology: The Effect of Changes in Kilovoltage and Filtration

It has been shown that, in practice, with many intensifying screens and screen type films, gonad dose need not increase when total filtrations of up to 3 mm of Al or when kVps up to 130 are used. Above this kVp, up to 180, slight increases may occur but are not such as to exceed those at 120 kVp: these slight increases need not deter those who wish to use high kilovoltage techniques for other reasons. Explanations are given for the conflicting statements in the literature. The importance of good beam limitation and the reduction of radiation leaks and off-focus radiation is stressed. The effects of scatter from filters and the component parts of light-beam diaphragms are discussed.