Intraluminal contrast enhancement and MR visualization of the bowel wall: Efficacy of PFOB

Abstract

Efforts to develop satisfactory intraluminal gastrointestinal contrast agents for magnetic resonance (MR) imaging have focused on depicting only the bowel lumen to exclude possible involvement by a pathologic process. To determine whether the bowel wall can be adequately imaged with use of the contrast agent and whether bowel wall visualization is a better index of the utility of the contrast agent for MR imaging, perfluoroocytlbromide (PFOB) was studied in human subjects. Twenty consecutive patients referred for abdominal or pelvic MR imaging were selected. All patients were given 400-1,000 mL of PFOB orally. MR imaging was performed at 0.38 and 1.5 T with T1- and T2-weighted spin-echo pulse sequences before and after administration of PFOB. The images were graded independently by three blinded readers. All readers reported significantly superior conspicuity of the bowel lumen and wall after PFOB than before PFOB administration (P less than .002). Among the post-PFOB studies, those with superior bowel wall visualization demonstrated superior overall image quality. In three patients, lesions were optimally demonstrated because the relationship of the process to the bowel wall, rather than just to the lumen, was identified. In two patients, masses arising within the bowel wall could be identified prospectively only when the bowel wall was adequately imaged. The authors conclude that while lumen identification is improved with PFOB, its greatest clinical utility may be in facilitating intestinal wall visualization.

Crohn's disease evaluation: Comparison of contrast-enhanced MR imaging and single-phase helical CT scanning

“…Kettritz et al (11) showed that the clinical severity of Crohn's disease correlated with the product of the degree of contrast enhancement with IV gadolinium, wall thickness, and length of diseased bowel segment. Negative intraluminal contrast agents for MR imaging have been described (12,15,20,21). Anderson et al (12) used oral perflubron in 12 patients with Crohn's disease, improving bowel wall visualization.…”

The value of hyoscine butylbromide in abdominal MR imaging with and without oral magnetic particles

“…The diamagnetic negative agent PFOB differs from OMP in that no susceptibility artifacts are expected to interfere with bowel-wall conspicuity [8,9]. However, using PFOB along with T1-weighted images at 1.0 T, Brown et al did not find a statistically significant improvement in bowel-wall conspicuity post-PFOB versus precontrast.…”

“…When negative MR bowel contrast agents were employed, investigators have found that peristalsis-related artifacts did not present a problem [4][5][6][7]. However, pharmacological motion suppression with glucagon has successfully been used to image the bowel wall after oral administration of the diamagnetic negative contrast agent perfluoroctylbromide (PFOB) [8,9]. The present study at 1.5 T was undertaken to evaluate the impact of anticholinergic hyoscine butylbromide upon motion artifacts, visualization of the bowel wall, and lesion delineation on T1-weighted SE images before and after oral administration of the negative bowel contrast agent oral magnetic particles (OMP) [Abdoscan, Ferristene (USAN), Nycomed Imaging AS, Oslo, Norway].…”

Formulation of radiographically detectable gastrointestinal contrast agents for magnetic resonance imaging: Effects of a barium sulfate additive on MR contrast agent effectiveness

“…Sedimentation would be more likely to occur in the colon. In a separate study, we found that the amount of intestinal filling seen radiographically using barium correlated with the distribution ofthe intraluminal contrast agent seen with MRI ( 12). Thus, barium can be used as an additive to establish small bowel filling radiographically prior to MR imaging.…”