Comparison Of Different Oral Contrast Agents To The Imaging Research Of Small Bowel MR Imaging In 1.5T

ObjectiveCompare three different oral contrast agents(0.1% barium sulfate, compound polyethylene glycol solution,2.5% mannitol solution) of the intestinal function expansion effect as well as the display of the intestinal wall to optimize oral contrast agents.Methods32 volunteers without abdominal surgery and gastrointestinal diseases participated in this test, and they have to take the contrast agents in blind. All the volunteers ate less food and cleaned intestines the day before the night. On the day of inspection they kept fasting, and they should eat oral contrast agents at a constant speed of 1500 ml an hour before checking (selected three contrast agents randomly:0.1%barium sulfate, compound polyethylene glycol solution,2.5% mannitol solution). They were given spasmolysis agent before checking, and butyl bromide scopolamine (specifications for 1 ml,10 mg) was intramuscular in 15 minutes before checking. MRI scanner was GE 1.5 T magnetic resonance imaging. The scanning position is supine; Scan sequences were the Cine sequences, SSFSE sequence, FIESTA sequence, diffusion weighted sequence (b=0 and 800 sec/mm2) and 2D Tl DualEcho sequence. Two radiologists read the images of MRE prospectively to obtain consistent results. Every paragraph of small intestine (duodenum, jejunum and ileum) was taken six-section diameters measuring expansion (outer wall-outer wall), and recorded the results. And in SSFSE sequence, FIESTA sequence and 2D T1 DualEcho sequence measured the signal-to-noise ratio of intestinal wall and lumen, and calculated contrast to noise ratio of the intestinal wall and lumen. In the process of scanning and after inspection, recorded the patients' adverse reactions. All data were processed by SPSS, analysis of variance were used to analysis. If p values< 0.05, we can think the difference was statistically significant.ResultsWithin 32 subjects,28 of them drank into the contrast agent in the allotted time and completed inspection.9 people were in mannitol group, polyethylene glycol group were 9 people, barium sulfate group were 10 people. Quantitative comparison showed that small intestine mean diameter of mannitol group was 23.57 mm; polyethylene glycol group was 27.29 mm; mean diameter of barium sulfate group was 23.85 mm. The best expansion of the small intestine was compound polyethylene glycol solution. The expansion of this group was better than mannitol and barium sulfate group (p< 0.05). Small intestine expansion degree of barium sulfate group was slightly better than mannitol group, but there was no statistical differences (p> 0.05). In SSFSE sequence, contrast to noise ratio of the colon wall and lumen of Mannitol group, polyethylene glycol group, and barium sulfate groups were 133.82,137.95, and 131.52, there was no significant statistical difference (p> 0.05). Contrast to noise ratio on the FIESTA sequence, three groups were 145.98, 164.62,158.64, and there was no significant statistical difference (p> 0.05). And contrast to noise ratio of three groups in 2D T1 DualEcho sequence were 69.82,72.99,72.15, there was also no significant statistical difference (p> 0.05). Each group found no serious adverse reactions.ConclusionThe expansion of the small intestine of compound polyethylene glycol solution was better than that of 2.5% mannitol solution and 0.1% barium sulfate. In SSFSE sequence, FIESTA sequence and 2D T1 DualEcho sequence, contrast to noise ratio of the colon wall and lumen of the three groups was no significant statistical difference. The small intestinal wall structure displayed clearly. Therefore, compound polyethylene glycol solution is an ideal oral contrast agent for MRE, should be the first choice.