Peristalsis gap sign at cine magnetic resonance imaging for diagnosing strangulated small bowel obstruction: feasibility study

Jpn J Radiol. 2011 Jan;29(1):11-8. doi: 10.1007/s11604-010-0508-z. Epub 2011 Jan 26.

Abstract

Purpose: The aim of this study was to determine the feasibility of cine magnetic resonance imaging (MRI) for diagnosing strangulated small bowel obstruction (SBO).

Materials and methods: This study included 38 patients with clinically confirmed SBO who had undergone cine MRI. Cine MRI scans were evaluated regarding the presence of the "peristalsis gap sign" (referring to an akinetic or severely hypokinetic closed loop), indicating strangulation. Computed tomography (CT) was performed in 34 of 38 patients with (n = 25) or without (n = 9) contrast enhancement. CT images were evaluated using a combination of criteria (presence of hyperattenuation, poor contrast enhancement, mesenteric edema, wall thickening, massive ascites) indicating strangulation. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of cine MRI and CT for the diagnosis of strangulation were calculated and compared using surgical findings and the clinical course as the reference standard.

Results: Sensitivity, specificity, PPV, and NPV of cine MRI were 100%, 92.9%, 83.3%, and 100%, respectively; and those of CT (of which 26.5% was performed without contrast enhancement) were 66.7%, 92.0%, 75.0%, and 88.5%, respectively. There was no significant difference in diagnostic accuracy between the two methods (P = 0.375).

Conclusion: Cine MRI is a feasible and promising technique for diagnosing strangulation.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Contrast Media
  • Feasibility Studies
  • Female
  • Humans
  • Image Interpretation, Computer-Assisted
  • Intestinal Obstruction / diagnosis*
  • Intestinal Obstruction / pathology
  • Intestine, Small*
  • Magnetic Resonance Imaging, Cine / methods*
  • Male
  • Middle Aged
  • Peristalsis*
  • Predictive Value of Tests
  • Sensitivity and Specificity
  • Tomography, X-Ray Computed

Substances

  • Contrast Media