Spatial Correspondence between Prone and Supine CT Colonography Images: Creating a Reference Standard

Matching corresponding locations between prone and supine CT colonography CTC images is difficult due to colonic deformations that occur between patient repositioning. We propose a novel method to allow a set of interpreting readers to establish a reference standard by matching corresponding locations in the prone and supine acquisitions. Independent matching of haustral folds was carried out for 17 CTC datasets by three readers, with the final reference standard being achieved in consensus. This resulted in 1743 reference standard points which have been made publicly available, along with the original CTC data at http://cmic.cs.ucl.ac.uk/CTC .