Head-to-head comparison of oral contrast agents for cross-sectional enterography: Small bowel distention, timing, and side effects

OBJECTIVE: To determine small bowel distention, scanning time, and side effects of commercially available oral contrast agents used in cross-sectional enterography. METHODS: Ten healthy volunteers ingested 2000 mL of water, methylcellulose, polyethylene glycol (PEG), or 1350 mL of low-concentration barium (LCB) followed by 500 mL water on different days. Magnetic resonance imaging occurred every 10 minutes from 30 to 90 minutes after ingestion. Small bowel distention was compared between time points and agents. Volunteers ranked side effects, drinking difficulty, and preference. RESULTS: By quantitative assessment, PEG and LCB distended small bowel loops better than water and methylcellulose (P < 0.0001). Time to optimal distention of the terminal ileum was from 51 to 72 minutes. Water and methylcellulose had the fewest side effects. Water was the most preferred contrast and PEG the least. CONCLUSIONS: Polyethylene glycol and LCB distend small bowel better than water and methylcellulose. Polyethylene glycol was the most difficult to drink and least preferred agent.