An interactive application for removal of bone information in CT-angiography

In this paper we present a method that allows removing bony structures and calcifications from CT angiography (CTA) data. It relies on two data sets, one with (CA) and one without (NCA) contrast agent. In contrast to current approaches, the algorithm uses local rigid matching of each single object. Therefore, it allows compensating motion of the patient during acquisition. Furthermore, the method uses a highly accurate surface-matching procedure so that local mismatches can be as small as 3 voxels and therefore even arteries near the bone are mostly separated correctly. The overall system requires about 20 minutes on a Pentium 4 2.4 GHz with 1 GByte RAM for a 700 MByte data set (CA+NCA) and is currently used in the clinic for evaluation purposes.