A feasibility study on the use of digital tomosynthesis with individually-acquired megavoltage portal images for target localization

Purpose: To determine the feasibility of using megavoltage (MV) images and digital tomosynthesis to determine the three dimensional (3D) localization of different objects. Materials and methods: Different phantom geometries were imaged using an electronic portal imaging device and digital tomosynthesis was used to reconstruct tomograms. These were compared with corresponding computed tomography (CT) images. Results: While in-plane resolution of the tomograms was comparable as that of the CT images, definite out-of-plane (depth) localization was restricted to 5 mm. Conclusion: The results confirm that it is possible to perform 3D localization of objects by using digital tomosynthesis for volumetric reconstructions from individually-acquired MV-quality portal images.