Artery-vein separation of human vasculature from 3D thoracic CT angio scans

This paper presents vascular tree reconstruction and artery-vein separation methods from 3D thoracic CT-angiography (CTA) images. In the methods, the lungs, blood vessels and the heart are segmented by using intensity-based thresholds and morphological operations. After the distance transform for the regions of blood vessels and the heart, we compute seed points that are the maxima of distance values. At each seed point, spheres are inflated until hit a boundary. The spheres and the connections between overlapped spheres make a graph representation of the 3D image. Once the pulmonary trunk is detected by using directions in the graph, blood vessels are traversed toward the heart, while merging and verifying branches. If a branch is linked to the pulmonary trunk, then all subsegmental trees of the branch are classified into pulmonary arteries. Otherwise, it is a pulmonary vein.