Reliability and role of plain film radiography and CT in the diagnosis of small-bower obstruction

OBJECTIVE. We compare the reliability and define the role of plain film radiography and CT in the assessment of various severities of small-bowel obstruction. MATERIALS AND METHODS. A blinded retrospective analysis was done on 78 patients who underwent plain abdominal radiography, CT, and enteroclysis to assess for suspected small-bowel obstruction. The findings at enteroclysis and the clinical outcomes were used as standards of reference. RESULTS. The sensitivity of plain film radiography for revealing small-bowel obstruction was 69% (44/64), and its specificity was 57% (8/14). Overall accuracy of plain film radiography was 67% (52/78). The sensitivity and specificity of CT were 64% (41/64) and 79% (11/14), respectively. Overall accuracy of CT was 67% (52/78). When obstructions were classified as low- and high-grade partial obstruction, plain film radiography and CT had sensitivities of 86% (24/28) and 82% (23/28), respectively, for high-grade obstruction and 56% (20/36) and 50% (18/36), respectively, for low-grade obstruction. CT revealed the cause of the small-bowel obstruction in 95% (39/41) of those patients in whom CT correctly showed the obstruction. CONCLUSION. Plain film radiography and CT had similar overall accuracies in showing small-bowel obstruction of various severities. Plain film radiography should remain the initial method of imaging patients with suspected small- bowel obstruction. The ability of CT to show the cause of small-bowell obstruction makes CT an important additional diagnostic tool when specific management issues must be addressed.