Reconstruction of airway tree based on topology and morphological operations

3D reconstruction of airway trees can provide intuitive and useful information for understanding human lung structure and function as well as assessing the presence of disease and its response to therapy. However, due to the partial volume effects, small airways may be undetectable on some slices of lung CT images. As a result, airway tree reconstructed by the existing methods based only on segmentation results will have broken airway branches and exhibit discontinuities. This paper proposes a complete airway tree reconstruction scheme to resolve this problem, which consists of two major steps. First, the broken segments are detected by incorporating the airway tree topology with the a priori knowledge of anatomy. Topology analysis is employed to provide information related to the a priori anatomical knowledge, so that it can be applied to lung images as guidance. Then, morphology-based and linear interpolation are applied so that unconnected airway segments will gradually merge together so that a complete airway tree can be reconstructed. The process stops when all the detected discontinuities have been processed. 3D visualization is also provided to demonstrate the effectiveness of the proposed scheme.