DOSE-AREA PRODUCT AND BODY DOSES

Dose-area product, a quantity easily measured in the X ray room, has b een proposed for use as a dose index for patient exposure in diagnosti c radiology. The most important aspect of the dose-area product is tha t it facilitates in practice the exposure dose assessment of individua l patients. Furthermore, empirical functions relating dose-area produc t to organ doses or to effective dose, quantities supposingly expressi ng the radiation detriment, were estimated by some authors. In this wo rk, a thorough study is attempted to investigate the relation of dose- area product likely to be measured, with the corresponding organ doses for a series of common radiographic examinations. For each examinatio n, the influence of beam quality, field size and shifts of the positio n of the field on the above relation are also studied. This is achieve d by means of organ doses obtained using MIRD-type human phantoms of a male and a female adult and a voxel phantom of a baby. A discussion o n the suitability of dose-area product as a quantity to assess dose de livered to the critical tissues of the patient will be included, highl ighting the conditions and uncertainties. The correlation of dose-area product and effective dose will be critically discussed.