A computerized three-dimensional treatment planning system utilizing interactive colour graphics

A new computerized radiation treatment planning system has been developed to aid in three-dimensional treatment planning. Using interactive colour graphics in conjunction with a DPD 11/45 computer, the system can take multiple transverse contours and construct a perspective display of the treatment region showing organ surfaces as well as cross-sectional contours. With interactively selected orientations, the display allows easy perception of the relative positioning of the treatment volume and neighbouring anatomy. For external beam treatment planning, interactive computer simulation is used to select diaphragm sizes which best conform to the target area while avoiding sensitive structures. Dose calculations for the selected beams are carried out on multiple transverse planes. The calculational planes and surfaces are displayed in perspective with radiation dosage displayed in an interactively manipulated colour display. Altogether the system provides an easy assessment of the volume to be irradiated, interactive selection of optimal arrangements of treatment fields and a means for visualizing and evaluating the resulting dose distributions.

A computer-assisted three-dimensional treatment planning system

The three-dimensional treatment planning system developed at the Rhode Island Hospital visualizes the spatial interrelationships of the radiation beam, the tumor, and the adjacent organs within the patient. It is possible to rotate and vary the scale of the display to better comprehend the extent of these structures. By viewing the display as if from along the radiation beam, one can design shaped treatment fields which best suit the three-dimensional nature of the disease. With this system, it is possible to reduce the volume of normal tissue which would typically be irradiated if two-dimensional treatment planning techniques and assumptions were employed.