An object-oriented system for 3D medical image analysis

As part of a European Commission-funded research project on medical image analysis, we have developed a system aimed at solving a real clinical problem: the outlining of the target volume and organs at risk for three-dimensional conformal radiation treatment planning. The clinical requirement is to make this process less tedious and time-consuming. We show how object-oriented design techniques can be used to good effect in a collaborative project such as this, so that image segmentation and other algorithms from a number of different partners in the consortium can be integrated into one system for comparative evaluation by the clinical partners. We describe in some detail two of these algorithms, one a straightforward region and volume grower, in which particular attention has been paid to adapting the user interface to suit clinical needs, and the other an interactive tool using b-spline surface patches for direct three-dimensional segmentation. We report on the clinical feedback we have received, which indicates that the most technically advanced algorithms are not necessarily the most useful from a clinician's point of view.