Omnipaque (iohexol, GE Healthcare), a low osmolar iodinated contrast agent has the potential to be better tolerated by patients than the more widely used high osmolality iodinated oral contrast agent, meglumine sodium diatrizoate (Gastroview, Mallinckrodt) for CT, according to a study presented Feb.21 at the Abdominal Radiology Course Meeting held by the Society of Gastrointestinal Radiology and the Society of Uroradiology in Orlando.
In the study, 100 patients were enrolled and 51 patients recieved diatrizoate and 49 received iohexol.
“Both oral contrast solutions were prepared in advance to achieve an iodine concentration of 8mg/mL and patients drank 1000 mL of contrast,” according to the lead author of the study, Christine M. Peterson, MD from Mallinckrodt Institute of Radiology, Washington University School of Medicine in St. Louis.
Peterson and colleagues found that patients reported a small but statistically significant preference for the taste of iohexol than when they were given diatrizoate (68 percent vs.50 percent).
The extent and density of GI tract opacification were similar between the two groups.“There was no statistical difference between mean attenuation value measurements in the stomach, duodenum, jejunum, or colon between the two study groups. There was, however, a small but statistically significant difference in mean attenuation value in the ileum, with a higher mean attenuation value in the iohexol group,” according to Peterson and colleagues.
With the cost, opacification properties and the frequency of adverse effects of the two agents being similar, iohexol may be helpful for ill patients who often have difficulty drinking oral contrast because of its taste being slightly better tolerated than diatrizoate.