Polyethylene glycol solution as an oral contrast agent for MR imaging of the small bowel

The development of fast single-shot heavy T2-weighted sequences that are able to provide motion-free images of static fluids has greatly increased interest in MR imaging of the small bowel. Various authors have advocated the use of a half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence as a reliable technique for imaging both the normal and abnormal small bowel [1,2,3]. However, poor distention of normal bowel loops in basal conditions has led researchers to perform small-bowel MR imaging using an oral contrast agent to distend the bowel lumen. Recently, two reports [4, 5] showed the utility of using tap water as an oral contrast agent in conjunction with the acquisition of a heavy T2-weighted sequence. However, the use of an absorbable agent, such as water, may not lead to optimal distention and visualization of distal ileal loops. We evaluated an oral isosmotic polyethylene glycol solution as an oral contrast agent for MR imaging of the small bowel in a population of healthy volunteers. Polyethylene glycol solution simulates the properties of water as it relates to signal intensity, with the added advantage of nonabsorbability, thus providing good distention of all the small-bowel loops from the jejunum to the terminal ileum.