Acute massive gastrointestinal bleeding: Detection and localization with arterial phase multi-detector row helical CT

Purpose: To prospectively evaluate accuracy of arterial phase multidetector row helical computed tomography (CT) for detection and localization of acute massive gastrointestinal (GI) bleeding, with angiography as referecne standard. Materials and Methods: Institutional review board approved this study; written informed consent was obtained from each patient or patient's family after procedures, including radiation dose, were explained. Twenty-six consecutive patients (17 men, nine women; age range, 18-89 years) had acute massive GI bleeding (defined as requirement of transfusin of at least 4 units of blood during 24 hours in the hospital or as hypotension with systolic blood pressure < 90 mm Hg) and underwent arterial phase multi-detector row CT before angiography. Scans were obtained during arterial phase to identify extravasation of contrast materialwith attenuation greater than 90 HU within bowel lumern; this finding was considered diagnostic for active GI bleeding. Presence of contrast medium extravasation in each anatomic location was recorded. Sensitivity, specificity, positive and negative predictive values, and accuracy of multi-detector row CT for detection of acute GI bleeding was assessed. Accuracy for localization of acute GI bleeding wasassessed by comparing locations of acute GI bleeding at both multi-detector row CT and angiography in each patient who had active bleeding. Results: Arterial phase multi-detector row CT depicted extravasation of contrast material in 21 of 26 patients. Overall location-based sensitivity, specificity, accuracy, and positive and negative predictive values of multi-detector row CT for detection of GI bleeding were 90.9% (20 of 22), 99% (107 of 109), respectively. Overall patient-based accuracy of multi-detector row CT for detection of acute GI bleeding was 88.5% (23 of 26). The location of contrast material extravasation on multi-detector row CT scans correspond exactly to that of active bleeding on angiograms in all patients with contrast medium extravasationat both multi-detector row CT and angiography. Conclusion: Arterial phase multi-detector row CT is accurate for detection and localization of bleeding sites in patients with acute massive GI bleeding. (c) RSNA, 2006.