Electronic Stool Subtraction Algorithm for CT Colonography Without Bowel Preparation

Reference #:

2005-022

Inventors/Contributors

C. Daniel Johnson M.D., Armando Manduca Ph.D., Robert J. Wentz, Michael J. Carston

Description

CT colonography (CTC) offers advantages for colon examinations such as lower risk and less patient discomfort. However, CTC requires complete bowel preparation (cleansing). The inconvenience and discomfort of this process greatly reduces patient compliance and is a major obstacle to widespread colorectal screening. An alternative is to tag the stool with an opacifying agent so that it is brighter than soft tissue and can be automatically recognized and reset to air values. However, such electronic stool subtraction is difficult to perform accurately, due to poorly labeled areas of stool, partial volume effects, and noise, particularly if the stool is in normal solid form. Some approaches combine tagging with dietary changes and mild forms of bowel preparation, resulting in primarily liquid stool which is easier to subtract, but the issue of patient compliance remains. We have developed a novel algorithm to electronically subtract stool prior to radiologist review that requires neither dietary changes nor any form of bowel preparation.

Patent Status

Pending