Depiction of Bowel Wall Visualization and Dilation in Abdominopelvic MDCT: Comparison of High-attenuation Contrast Medium, Water and Whole Milk

Background: High-attenuation oral contrast agents in the form of iodine solutions or barium suspensions have been used traditionally and effectively for abdominal computed tomography (CT) examinations. Apart from the unpleasant taste, there are relatively few disadvantages that may affect interpretation, such as pseudotumor formation due to incomplete mixing of contrast material with the bowel contents and poor mural discrimination. Thus, low-attenuation oral contrast materials are needed. Purpose: The aim of this study was to evaluate the efficiency of whole milk as a low-attenuation contrast agent compared with water-soluble contrast medium and water for abdomi-nopelvic CT. Methods: A total of 152 patients were randomly assigned to receive whole milk (4%), water or water-soluble contrast medium (Optiral). All CT scans were performed using a 64-multidetector CT scanner with a 0.35-second rotation time. Two radiologists were responsible for reviewing the images to assess bowel wall enhancement and bowel dilation. Results: There were no differences in average dilation scores among the three groups for duodenum and jejunum. The average dilation score in the milk group was higher than that in the water-soluble contrast medium group in the antrum, and there was no difference between water and milk. For the ileum, there were no differences in the average dilation scores in the milk and water-soluble contrast medium groups, and milk produced better dilation compared with water. Bowel enhancement in the water and milk groups was stronger than that in the water-soluble contrast medium group. The major side effects of milk were nausea and flatulence. Conclusion: We concluded that abdominopelvic multidetector CT with whole milk provides better bowel dilation and wall visualization compared with high-attenuation contrast medium. Whole milk and water have potential as good oral contrast materials for bowel discrimination. However, whole milk should be considered as an alternative to water in cases of disease suspected in the pelvis.