Virtual Contrast for Coronary Vessels Based on Level Set Generated Subvoxel Accurate Centerlines. - Ingmar Bitter; Robert L. Van Uitert Jr.; Ivo Wolf; Efstathia Tzatha; Ahmed M. Gharib; Ronald M. Summers; Hans-Peter Meinzer; Roderic I. Pettigrew (Int. J. Biomed. Imaging, 2006)