Theme |
CT colonography |
Title |
CT colonography using stool tagging method |
Author |
Junji Ueno |
School of Health Sciences, The University of Tokushima Faculty of Medicine |
Author |
Shoichiro Takao |
School of Health Sciences, The University of Tokushima Faculty of Medicine |
Author |
Toshiya Okahisa |
Institute of Health Biosciences, The University of Tokushima Graduate School |
Author |
Mitsuru Kubo |
Graduate School of Engineering, The University of Tokushima Graduate School |
Author |
Noboru Niki |
Graduate School of Engineering, The University of Tokushima Graduate School |
[ Summary ] |
With the administration of small amounts of oral contrast agents, residual fluids and feces in the colon become identifiable, due to their high density. Stool tagging or labeling with orally ingested high density contrast mediums are adequate to distinguish fecal materials from mucosal lesions, even without the routine administration of cathartics. In our experience, water-soluble iodinated contrast mediums work best for opacification of colonic contents. Software developed in-house is used to subtract the tagged colonic contents from the CT source images as a post-processing step, leaving soft-tissue element of the colonic wall. The result is an image data set suitable for virtual endoscopy in which significant colonic lesions are easily recognizable. Patients feel reluctant to have examinations of the colon if there is a need for bowel cleansing when having sigmoidoscopies, colonoscopies, or double contrast barium enemas. For these reasons, cathartic-free CT colonography is being investigated and used clinically to evaluate the colon for polyps and cancers. Stool tagging and digital subtraction bowel cleansing may contribute to a more easily tolerated method of examining the colon. |