Multidetector Computed Tomography Mesentericography for the Diagnosis of Obscure Gastrointestinal Bleeding

Purpose: To evaluate the diagnostic yield of 16-row multidetector computed tomography (CT) mesentericography in patients with obscure gastrointestinal bleeding. Materials and Methods: The radiological information system database was used to retrospectively identify all patients in whom CT mesentericography (CTM) was performed for the diagnosis of obscure gastrointestinal bleeding between July 2002 and September 2006. A subsequent prospective study was conducted between October 2006 and September 2009 to evaluate CTM in patients with major obscure gastrointestinal bleeding. The retrospectively identified patients (six patients) as well as the prospectively evaluated patients (seven patients) constitute the study population. Following mesenteric DSA the catheter was left in the superior mesenteric artery, the patient was transferred to the CT suite and am was carried out by scanning the abdomen after contrast material injection via the catheter. Active bleeding was suspected if a focal area of high attenuation consistent with contrast material extravasation was found within the bowel lumen. Results: CTM detected the site of active bleeding in three of 13 patients (23%). In the subpopulation of patients who were prospectively evaluated, CT mesentericography identified the site of active bleeding in one of seven patients (14%). Depiction of active bleeding by CTM prompted surgical intervention in each case and surgery confirmed the findings of CT mesentericography. Conclusion: Due to the relatively low rate of positive findings and inherent drawbacks, we feel that CTM cannot be recommended in general. However, in selected patients who are continuously bleeding at a low rate and in whom iv-CT was negative, CT mesentericography might be helpful.