[Optimisation in brachytherapy]

Advances in technology have initiated a process of redefinition of planning and evaluation of brachytherapy. The new approach involves conformal positioning of a source configuration for which the treatment isodose contour is adapted to the shape of the target volume which is defined by 3D dimensional imaging. A good implant aims for a balance between good coverage of the target volume, a high dose uniformity inside the target volume and a steep dose fall-off outside the target volume. Computer hardware and software is now available to obtain a high level of sophistication, for instance in treatment planning. In addition, new after loading equipment became available allowing a large variety in source placement in the catheters. To facilitate optimisation procedures, new parameters for the judgement of the quality of the implant have been suggested.