3D-imaging using mobile low-end C-arm systems

During the last years, three-dimensional X-ray imaging has become a well-established imaging modality, setting the golden standard for spatial resolution in three-dimensional X-ray imaging. Firstly introduced on a motorized C-arm system, it gained benefit from the high spatial resolution of the image intensifier. Using cone-beam reconstruction, it provided fast access to truly three-dimensional imaging with isotropic voxel dimensions. However, the non-rigid mechanics and the image distortion in the image intensifier required dedicated calibration processes and obligated the developers to use the most stable and reliable system in the C-arm device family. The need for system calibration also required the system to be able to reproducibly adjust the C-arm to the pre-calibrated positions, which seemed only possible with the motorized movement of a high-end system. On mobile, non-motorized C-arm systems, which are often used for guiding surgical procedures, however, 3D application has not been feasible due to the non-reproducibility of the mechanical movement. In this paper, first results regarding the feasibility of this approach are presented. The data were acquired on a Philips BV 26 surgical C-arm. This device is fully movable. The "C" arc is adjusted manually.