CT diagnosis of the nature of bowel obstruction: morphological evaluation of the transition point.

PURPOSE: This study evaluated transition-point morphology for defining the nature of bowel obstructions. MATERIALS AND METHODS: Computed tomography (CT) examinations of 95 patients affected by severe bowel obstruction (23 neoplastic, 72 nonneoplastic) were retrospectively reviewed. RESULTS: The transition point was identified in 89 patients (94%); morphology in relation to the proximal loop was concave in 64 cases (68%), linear in five (5%) and convex in 20 (21%). Concave transition-point morphology was indicative of a nonneoplastic condition, with sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy values of 89%, 100%, 100%, 74% and 92%, respectively. A linear shape had almost identical incidence among neoplastic (60%) and nonneoplastic (40%) conditions. A convex appearance correlated with neoplastic disease with sensitivity, specificity, PPV, NPV and diagnostic accuracy values of 87%, 100%, 100%, 96% and 97%, respectively. CONCLUSIONS: In the case of bowel obstruction, transitionpoint detection indicates the obstruction site, whereas its morphological evaluation can contribute to defining the nature of the obstruction. A concave morphology indicates a nonneoplastic condition with a high probability; a convex morphology correlates with neoplastic disease, whereas linearity is not significant.

Prognostic value of MDCT in malignant large-bowel obstructions.

PURPOSE: This study aimed to correlate multidetector-row computed tomography (MDCT) findings and postoperative prognosis in malignant large-bowel obstructions. MATERIALS AND METHODS: Twenty-seven patients affected by malignant colonic obstruction underwent MDCT examination and were analysed for obstruction site, colon-wall morphology, intestinal content alterations and transverse diameter of ascending colon. RESULTS: Obstruction site was recognised in all cases (5/27 ascending colon; 1/27 transverse colon; 11/27 descending colon; 10/27 sigma-rectum). Intestinal content consisted of mainly air in 3/27 patients, mainly fluid in 11/27 and air-fluid levels in 13/27. In 9/27 cases, pneumatosis intestinalis was found. Mean maximum diameter of the ascending colon was 8.2 cm. Overall mortality rate was 37%. An intestinal content mainly consisting of air (3/3 living patients) or fluid (7/11 living patients) were indicative of good prognosis. Air-fluid level detection indicated poor prognosis in 7/13 cases. Pneumatosis intestinalis (7/9 deceased patients) and ascending colon diameter values > or =10 cm (7/7 deceased patients) were indicative of poor prognosis. CONCLUSIONS: MDCT can identify the presence and site of malignant large-bowel obstructions and may provide useful prognostic information.