Decreased-Purgation CT Colonography: State of the Art

Abstract

In the setting of CT colonography (CTC), decreasing bowel preparation measures may help to optimize colorectal cancer screening compliance without compromising accuracy. Decreased-purgation or wholly noncathartic CTC, known as nonconventional CTC, may be accomplished in conjunction with fecal tagging. Image post-processing technologies such as electronic cleansing and computer-aided detection may boost accuracy and decrease the need for bowel preparation even further. We review pre-study preparation and image post-processing techniques that have been described in nonconventionalpreparation CTC studies over the past 10 years. We explore in detail specific aspects of nonconventional cathartic and fecal tagging regimens, including substance, dose, and time frame of ingestion.

Spectral material characterization with dual-energy CT: comparison of commercial and investigative technologies in phantoms

“…Two pairs of materials, iodine/barium and calcium/gadolinium, had near-equal DE slopes with every scanning technique. Of particular clinical interest may be the similarity between DE slopes of iodine and barium, materials which may be found in close proximity to one another in CT colonography (CTC), wherein concurrent oral barium and intravenous iodine administration may facilitate evaluation of colonic mucosa with decreased-purgation (20,33). Spectral bowel cleansing at CTC with DECT-based removal of ingested contrast material has been accomplished (19), but a technique for accurate separation of intraluminal barium from submucosal intravenous iodine at CTC remains to be established.…”