IGRT and its Quality Assurance at the DKFZ

Abstract

Modern treatment techniques like IMRT offer the possibility to deliver highly conformal dose distributions. Therefore accurate patient positioning is necessary. This, in turn, requires image guidance techniques. In-room CT and cone beam CT are two possibilities to realize image-guided radiation therapy. At the DKFZ we have the opportunity to work with both techniques. Special software delivers offset vectors for table movement to compensate possible misalignment in positioning. This issue needs a daily quality assurance, which is done with the help of the QUASA^TM Penta-Guide Phantom. The QA procedure simulates a misalignment, which has to be detected and corrected by our TPS Virtuos or by Siemens RTT . A special adapter feature the possibility to use this phantom outside of the laser marked isocenter, but in a special stereotactic setup commonly used for imaging at the DKFZ.