title: Multidetector CT angiography in acute gastrointestinal bleeding: why, when, and how.
abstract: Acute gastrointestinal (GI) bleeding remains an important cause of emergency hospital admissions, with substantial related morbidity and mortality. Bleeding may relate to the upper or lower GI tract, with the dividing anatomic landmark between these two regions being the ligament of Treitz. The widespread availability of endoscopic equipment has had an important effect on the rapid identification and treatment of the bleeding source. However, the choice of upper or lower GI endoscopy is largely dictated by the clinical presentation, which in many cases proves misleading. Furthermore, there remains a large group of patients with negative endoscopic results or failed endoscopy, in whom additional techniques are required to identify the source of GI bleeding. Multidetector computed tomography (CT) with its speed, resolution, multiplanar techniques, and angiographic capabilities allows excellent visualization of both the small and large bowel. Multiphasic multidetector CT allows direct demonstration of bleeding into the bowel and is helpful in the acute setting for visualization of the bleeding source and its characterization. Thus, multidetector CT angiography provides a time-efficient method for directing and planning therapy for patients with acute GI bleeding. The additional information provided by multidetector CT angiography before attempts at therapeutic angiographic procedures leads to faster selective catheterization of bleeding vessels, thereby facilitating embolization. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.313105206/-/DC1.
authors: Department of Radiology, Foundation Hôpital Saint-Joseph, Paris, France.
authors: Yann
authors: Y
authors: Geffroy
authors: Mathieu H
authors: MH
authors: Rodallec
authors: Isabelle
authors: I
authors: Boulay-Coletta
authors: Marie-Christine
authors: MC
authors: Jullès
authors: Marie-Christine
authors: MC
authors: Fullès
authors: Catherine
authors: C
authors: Ridereau-Zins
authors: Marc
authors: M
authors: Zins
mesh_terms: D000208:Acute Disease; D000792:Angiography / Q000379:methods*; D003287:Contrast Media; D003937:Diagnosis, Differential; D004621:Embolization, Therapeutic; D016099:Endoscopy, Gastrointestinal / Q000379:methods; D006471:Gastrointestinal Hemorrhage / Q000000981:diagnostic imaging* / Q000628:therapy; D006801:Humans; D011857:Radiographic Image Interpretation, Computer-Assisted; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media