Full 3d Roi Image Reconstruction from Highly Collimated Computed Tomography

We introduce a novel method for full 3D Region Of Interest (ROI) reconstruction in computed tomography (CT), called Searchlight CT, which reduces the overall radiation exposure when primarily the reconstruction of a specified ROI is required. To achieve this goal, the Searchlight CT approach restricts the acquisition essentially to X-rays passing through the ROI, yet the algorithm provides a stable and robust reconstruction inside the ROI. The Searchlight CT approach is not limited to a specific mode of acquisition. In fact, it is capable of converting virtually any 3D reconstruction formula into an ROI reconstruction which uses only the radiation which is intersecting the ROI.