Multiplanar Imaging Evaluation of Specific Signs in Identifying 'Closed Loop Small Bowel Obstruction' with Multidetector Computed Tomography

Objective: Closed-loop obstruction (CLO) is a relatively uncommon clinical entity. Ischemic changes are commonly associated with this type of obstruction. Early diagnosis becomes very critical to choose the pathway to manage the patients, surgical or medical and can be also lifesaving. The aim of this study was to determine the diagnostic impact of multiplanar evaluation of specific signs in identifying CLO with multidetector computed tomography (MDCT). Material and Methods: Between June 2012 and December 2017, a retrospective search has been done from medical records of hospital information system for the words “closed-loop, small bowel obstruction” on CT reports for adult patients (>18 years of age) undergoing MDCT imaging. One hundred and six patients, who meet the criteria, were included in the study. Multidetector computed tomography exams were performed with 16 slices scanner. Images were then evaluated by multiplanar reformatting on the workstation in terms of specific findings of CLO. The results were correlated with the surgical diagnosis. The sensitivity, the specifity and the accuracy of multiplanar MDCT evaluation were calculated. Results: We have diagnosed sixty-two patients with CLO with specific signs. All of the cases had dilated U/C shaped bowel loops. Forty patients had the beak sign, twenty-five had mesenteric congestion sign, ten had radial distribution, and four of them had the whirl sign. Sixteen patients had MDCT signs of strangulation including intestinal pneumatosis, thickening of the bowel wall, mesenteric congestion, engorgement of mesenteric vessels, increased haziness and blurring of the mesenteric structures. Twelve patients were excluded from the study due to missing surgical data. Fifty of the 62 patients underwent surgery in our hospital. There was no statistically significant difference between ischemia at the surgery and correct diagnosis of CLO at MDCT (p=0.88). The mean sensitivity, specificity, and accuracy for the detection of CLO were found to be 94%, 90%, and 95% respectively. Conclusion: Multidetector computed tomography with the capability of multi planar imaging is a valuable modality for demonstrating the specific signs of CLO.