Positive oral CT contrast improves detection of malignant deposits in intraabdominal nonsolid organs

Yeh and team's retrospective study included 265 patients (133 men, 132 women; median age, 61 years) who underwent an abdominopelvic CT examination where the report did not suggest presence of malignant deposits and subsequent CT examination within 6 months where the report indicated at least one unequivocal malignant deposit. Examinations used positive (iohexol; n=100) or neutral (water; n=165) oral agents. While reviewing images to assess visibility of deposits, a board-certified abdominal radiologist also assessed adequacy of bowel filling with oral contrast material.

NPV of CT for detection of malignant deposits in intraabdominal nonsolid organs was 65.8% for examinations using positive oral contrast material with adequate bowel filling, 45.2% for positive oral contrast material with inadequate bowel filling (p=.07), and 35.2% for neutral oral contrast material regardless of adequacy of bowel filling (p=.002).

"Results may differ when studying other types of contrast material regimens," the authors of this AJR article noted, including barium-based, hyperosmolar iodine, sugar-alcohol neutral, or experimental dark oral agents.