Precise segmentation of the left atrium in C-arm CT volumes with applications to atrial fibrillation ablation

A patient-specific left atrium (LA) model extracted from intra-operative C-arm CT plays an important role in planning for transcatheter left atrial fibrillation ablation. Overlaying the LA model onto 2D fluoroscopic images provides valuable visual guidance during the intervention. However, automatic segmentation of the LA, together with the left atrial appendage (LAA) and the pulmonary vein (PV) trunks, is challenging due to the large structural variations and imaging artifacts. In this paper we exploit a part based LA model to handle the structural variations and different parts are then merged into a consolidated mesh. The connection region between the PV/LAA and the LA chamber is segmented precisely by enforcing both image boundary delineation accuracy and mesh smoothness. Furthermore, the boundary between parts is optimized to improve the mesh part labeling accuracy.