Purpose: We retrospectively evaluated the radiological findings observed at plain abdominal film, abdominal sonography and abdominal CT performed in 66 patients with surgically proven small bowel volvulus.
Material and methods: Sixty-six patients (35 women and 31 men, ranging in age 38-77 years) with surgically proven small bowel volvulus were submitted to plain film, sonography and CT of the abdomen. Abdominal plain film was performed in the upright position (postero-anterior view) in 46 cases, and in the supine position in 20 cases. On plain abdominal film we evaluated the following findings: bowel loops dilatation, air-fluid levels and site of obstruction. At abdominal US, performed with 3.5 e 7.5 MHz probes, we retrospectively searched for: bowel loop dilatation, bowel wall thickening, peristalsis alteration, extraluminal fluid. CT was performed with a helical unit (thickness 4 mm, reconstruction interval 4 mm, pitch 1.5), after intravenous contrast agent (120 ml) infusion (3 ml/s, 55 s acquisition delay from bolus starting) and using a power injector. The following CT findings were searched for: whirl sign, beak sign, extraluminal fluid, bowel loop dilatation, bowel wall thickening, bowel wall or mesenteric alterations.
Results: Plain abdominal film showed the following findings: air-fluid levels (92.4% of cases), bowel loops dilatation (71.2%), site of obstruction (42.4%). Abdominal sonography demonstrated bowel loop dilatation (48.5%), extraluminal fluid (48.5%), peristalsis alteration (27.3%), bowel wall thickening (27.3%). The most frequent CT findings were: bowel loop dilatation (95.5%), bowel wall thickening (78.8%), beak sign (69.7%), mesenteric alterations (66.7%), extraluminal fluid (54.5%), whirl sign (13.6%).
Conclusions: Air-fluid levels and bowel loop dilatation were the most frequent radiological findings in our series. Plain abdominal film allowed us to identify signs of obstruction, whereas signs of bowel wall necrosis were accurately shown by abdominal CT.