An Algorithm for Analyzing Computed Tomography Images in Case of Suspected Strangulation in Adhesive Intestinal Obstruction

Introduction. Adhesive intestinal obstruction is responsible for up to 2.4% of all laparotomies. The choice of patient management strategy directly depends on whether there are indications (including CT findings) of intestinal obstruction and/or ischemia of the intestinal wall.

The Aim of Our Study. Identification of CT signs that are reliably associated with ischemic intestinal changes, and CT predictors of irreversible intestinal changes that may require surgical resection.

Material and Methods. The study used 53 retrospective CT scans of the abdomen with intravenous contrast enhancement, performed at the time of admission on patients undergoing surgery for adhesive obstruction. These scans were evaluated for the following signs: the presence of the “beak” sign in the transition zones, the thickness of the intestinal wall, a decrease in contrast of the intestinal wall, local edema of mesenteric tissue, the presence of “closed-loop” obstruction, a small-bowel faeces sign, and the “fat-notch” sign.

Results. The study found that a thickened intestinal wall, a prominent “beak” at two adjacent points, the presence of a “closed loop” obstruction, and poor contrast between the intestinal wall and a small-bowel faeces sign were all independent predictors of the need for intestinal resection. Based on the obtained results, an algorithm for visual assessment of the intestine on CT of abdominal organs in patients with adhesive intestinal obstruction was proposed.

Conclusion. Using the method of computed tomography with intravenous contrast enhancement and visual analysis of the obtained tomograms according to the proposed algorithm, it is possible to detect signs of strangulation and adhesive intestinal obstruction with sensitivity of 69%, specificity of 97%, and accuracy of 88%.

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