Po‐Poster ‐ 23: The geometrical accuracy of 3D reconstructions from orthogonal views using distortion corrected image intensifier images

Three‐dimensional source localization in brachytherapy is integral to the treatment planning process. Many high dose rate (HDR) brachytherapy facilities employ a mobile C‐arm to accomplish this task. Digital images captured directly from an image intensifier are distorted and must be dewarped prior to their use in treatment planning. This preliminary study examines the accuracy of 3D reconstructions of a known object using digital images that have had the distortion removed using a simple mathematical model. Orthogonal images of a known test object were acquired and corrected, and were then used to reconstruct the object. The cumulative uncertainty in the reconstructed location of fiducial marks on the object over 18 cm length orientation was 1.2 mm, compared to 1.0 mm over a 16 cm length using CR film. Potential improvements to image processing methods employed in this study are also discussed.