Supine and prone CT colonography registration by matching graphs of teniae coli

This paper proposes a registration method for supine and prone CTC scans. The method matches graphs built using the teniae coli, three muscles that run the length of the colon. The teniae are visible on CTC and were detected using fully-automatically software. Then key points of the teniae were obtained by non-uniformed sampling of the teniae. Graphs were built using these key points. The colon registration was formulated as a graph matching problem. Mean field theory was applied to match the graphs. The proposed method was tested on 10 pairs of supine and prone CTC scans. The average registration error was 2.5cm (±0.7 cm, 95% C.I. [2.1 2.9]), significantly improving the baseline graph matching method for CTC registration.