A three dimensional digitzation system for conventional radiation therapy simulation

Abstract

While the majority of patients receiving external beam radiation therapy treatments are planned by CT-simulation, a significant number of them are still planned by using conventional simulators for various reasons. The information collection process in a conventional simulation is often fragmented and with primitive tools. For example, in many institutions patient body contours are still acquired by using solder wires and tracing papers, a time-consuming and error prone procedure. We have developed a three-dimensional digitization system to assist the information acquisition process at conventional simulations. The system consists of an infrared camera assembly, a wireless digitizer probe and a window based software. The system can provide 3D coordinates of any points in space accessible by the probe with sub-millimeter accuracy. It can be used to capture patient body contours, to record the coordinates of portal points, and to take various measurements for dose calculations as well as for patient setup. The software can display all the captured data together with the planned treatment fields to provide a comprehensive geometric verification of the treatment configuration. The system can also transfer all the information to dose planning programs in Dicom-RT format, providing an integrated information flow from simulation to dose planning.