Colour visualization as an aid to the comparison of treatment plans for prostatic carcinoma

The conventional treatment plan is usually presented as a longitudinal set of axial cross-sections showing the patient contour and selected anatomical features, together with a set of isodose lines. It is difficult to interpret the correlation between dose, target and organs at risk, and the comparison of several plans is time-consuming and highly subjective. This procedure has been improved by modifying a treatment planning system to provide 'images of regret', in which regions are shown in appropriate colour if the planned dose distribution is at variance with prescribed conditions defining limits of acceptability. The method has been used for planning treatment for localized prostatic cancer, and found to be useful for the rapid selection of the optimal treatment plan from a set of alternatives.