OC-0409: Deformable image registration with guaranteed local rigidity
Lars König, Alexander Derksen, Stefan Heldmann, Nils Papenberg, Jan Modersitzki, B. Haas · Radiotherapy and Oncology · 2015
3rd ESTRO Forum 2015 S197 shallow depths with a Markus parallel plate ionization chamber (PTW, type 23343).Second, the rotation of the Xray tube was implemented in the MC code to mimic the volumetric (3D) acquisition mode, whose dosimetric validation is currently undergoing.Results: Dose measurements and MC simulation are in agreement: a passing rate greater than 95% and 82 % was observed for depth dose curves and dose profiles respectively, for local gamma-index criteria of 2%/2 mm (cf.Fig. 1.).Some discrepancies were noticed, in the first millimeters of the depth dose curves, resulting of difficulties to perform accurate measurements at the surface, even with a plate chamber.Finally, the HVL values obtained by simulation were in close agreement with measured values (cf.Tab.1.).Tab. 1. Measured and calculated HVL values at 120 kV with and without bowtie filter. Conclusions:The XVI MC model developed with PENELOPE was successfully validated in 2D mode against an extensive set of measurements, and preliminary results for the 3D acquisition mode are very encouraging.Future work includes a comprehensive validation of the simulation tool by comparing simulation results with dosimetric measurements in anthropomorphic phantoms.