Abstract
To draw the maximum advantage from accelerated heavy ions requires a treatment plan that enables us to concentrate sufficient dose to a target region and to spare surrounding critical organs. Powerful computer support is needed to implement such a plan because it is an iterative process in which we need quick changes of displayed images including threedimensional (3D) models, and high-speed computation of 3D dose distributions. Our treatment planning system, which is called HIPLAN (Heavy Ion Plan), is constructed on modern graphical workstations running UNIX and X Window System. It implements functions required for 3D treatment planning and enables us to determine the parameters to control the irradiation system of HIMAC. In this paper we describe the software specifications, system architecture, hardware platforms and operation examples of the present version of HIPLAN, and discuss future prospects.
