Prospective Randomized Trial of Iohexol 350 Versus Meglumine Sodium Diatrizoate as an Oral Contrast Agent for Abdominopelvic Computed Tomography

Abstract

To compare the efficacy and patient tolerance of iohexol and meglumine sodium diatrizoate as oral contrast agents for computed tomography (CT). One hundred patients were randomly assigned to drink 1000 mL of either meglumine sodium diatrizoate or iohexol 350 before their abdominopelvic CT examination. The images were evaluated independently and in a blinded fashion by 2 radiologists who scored the extent and density of bowel opacification. Attenuation value measurements were obtained in representative areas of each gastrointestinal tract segment (stomach, duodenum, jejunum, ileum, and colon) by a research technologist. Patients' tolerance of the oral contrast agent was assessed through a questionnaire administered immediately after the CT and with a follow-up phone call 2 to 3 days later. For most of the bowel, there was no statistically significant difference in the extent or degree of opacification between the 2 contrast agents. Opacification of the ileum was better with iohexol. There was no statistically significant difference between the 2 agents in adverse effects. Patients had a small but statistically significant preference for the taste of iohexol. Iohexol 350 is a satisfactory oral contrast agent for abdominopelvic CT. It opacifies the gastrointestinal tract as well as meglumine sodium diatrizoate does, and patients prefer the taste of iohexol to that of diatrizoate.