A method for selective removal of out-of-plane structures in digital tomosynthesis

The quality of the reconstructed images in Digital Tomosynthesis is often limited by the presence of artifacts due to blur from planes other than the fulcrum plane. A technique has been developed for the separation and subsequent removal of unrelated structures from the reconstructed plane. The method involves the reconstruction of the blur originating in user-selected "noisy" planes as it appears on the plane of interest. This is achieved by projecting the reconstructed images of the selected plane on the image formation plane for all viewing angles, and subsequently, synthesizing its blurred image on the plane of interest. There are no restrictions as to the identity of the planes to be removed. Reproduction of the noise is performed using the tomosynthesis algorithm itself, thus the technique can be modified to suit any reconstruction algorithm. The proposed technique was implemented on the Multiple Projection Algorithm and was experimentally evaluated using a radiotherapy simulator unit.