Marnix Christiaan Maas1, Corijn Kamerling1, Simon van Kranen1, Sara Muller2, Jelle Teertstra2, Floris Pos1, Christoph Schneider1, Jan Jakob Sonke1, Marcel van Herk1
1Radiotherapy, NKI-AVL, Amsterdam, Netherlands; 2Radiology, NKI-AVL, Amsterdam, Netherlands
Using an endorectal coil (ERC) greatly improves the quality of prostate MR images, but results in displacements and deformations of the organ and its surrounding tissues, causing systematic errors in intensity modulated radiation therapy (IMRT) planning. We have implemented an image based method for the deformable registration of endorectal to non-endorectal MR images. Here we present a validation of this method using markers placed on corresponding anatomical structures in pairs of fixed and deformed images. The registration method was found to be feasible, and our results suggest that sufficient accuracy for use in radiotherapy planning is attainable.