CT of Small-Bowel Ischemia Associated with Obstruction in Emergency Department Patients: Diagnostic Performance Evaluation

Abstract

Diagnostic performance assessment of CT for the diagnosis of small-bowel ischemia revealed poor prospective interpretation sensitivity.

Multidetector CT findings in patients with mesenteric ischaemia following cardiopulmonary bypass surgery

“…Previous studies have also highlighted poor interreader agreement for the assessment of differential mural enhancement [18]. The poor result for venous thrombosis is likely explained by its low prevalence in the patient group; the two readers each identified the sign once in separate patients, but on consensus, this was deemed to be owing to artefact.…”

“…Although small bowel faeces sign is typically associated with bowel obstruction, some studies have also shown a significant association of the sign with the presence of small bowel ischemia [18,19]. Differential mural enhancement had the highest sensitivity for diagnosis (0.92), but specificity was only 0.50.…”

“…Signs, such as pneumatosis, superior mesenteric artery occlusion, portal venous gas and reduced mural enhancement, have been shown to have specificities of 1.00 but sensitivities not .0.57 and more typically ,0.30 [12,14,18,20]. The choice of a control group in which the diagnosis of ischaemic bowel was a clinical possibility serves to better parallel daily practice; undoubtedly, the respective specificities would be higher if a healthy patient control group was selected.…”

Early diagnosis of bowel obstruction and strangulation by computed tomography in emergency department

“…Other fi ndings suggestive of ischemia and risk of strangulation, but not independently sensitive and specifi c, include bowel wall thickening, mesenteric edema with fat stranding appearance, ascites, mesenteric vascular congestion, intramural pneumatosis, and portal venous gas. [1,22] CT scan also provides a global evaluation of the abdomen and this is especially relevant in the emergency department when evaluating a patient with acute abdomen when multiple etiologies are being considered in the differential diagnosis. [10,17] Thrombus can be seen in the mesenteric artery or vein in central occlusion on CT performed after intravascular contrast administration.…”

“…Bowel content serves as a contrast agent and oral contrast will also hamper the ability to assess the enhancement of the bowel wall. [1,22] The limitation of CT scan is its low sensitivity for detecting partial SBO. Enteroclysis (small bowel enema) is regarded as one of the most accurate radiographic tests for the diagnosis of SBO, with a sensitivity and specifi city being approximately 100%.…”