CT differentiation between necrotic and nonnecrotic small bowel in closed loop and strangulating obstruction

Background: The purpose of this study was to evaluate computed tomographic (CT) findings for predicting the presence of intestinal necrosis in patient s with closed loop and strangulating obstruction of the small bowel. Methods: Twenty-five patients with surgically confirmed closed loop and str angulating obstruction were divided into two groups with (n = 16) and witho ut (n = 9) intestinal necrosis. By using univariate and multivariate statis tical procedures, we evaluated the differences in CT findings between the t wo groups on the basis of the following six findings: bowel dilatation of s trangulated loops (bowel dilatation), wall thickening of strangulated intes tines (wall thickening), ascites, vascular dilatation of affected mesenteri es (vascular dilatation), elevation of mesenteric attenuation (mesenteric a ttenuation), and radial distribution of the mesenteric vessels (radial dist ribution). Results: Of the six findings, ascites, vascular dilatation, mesenteric atte nuation, and radial distribution provided significant discriminating findin gs between the two groups on univariate analysis. On multivariate analysis, mesenteric attenuation was the most important discriminative factor, follo wed by radial distribution and ascites. Using these three parameters, the C T was correlated with the surgical findings in 15 of the 16 patients in the necrosis group (sensitivity = 93.8%) and in eight of the nine patients in the nonnecrosis group (specificity 88.9%). The overall accuracy was 92.0%. Conclusions: Mesenteric attenuation, radial distribution, and ascites, depi cted on CT differentiate well between necrosis and nonnecrosis of the small bowel in patients with closed loop and strangulating obstruction.