The critical role of CT angiography in the detection and therapy of lower gastro-intestinal bleeding.

Lower gastro-intestinal bleeding (LGIB) is defined as a bleeding site localised in the colon or anorectum. (1) In the past, the diagnosis of LGIB has been a serious challenge for the radiology department because of its possible intermittent character, making it difficult to pinpoint the bleeding site. Patients with a LGIB will typically have undergone a long diagnostic work-up before they end up on the interventional radiology department. The development of multi-detector computed tomography (CT) has made radiological diagnosis of LGIB easier. CT is not only able to localize the active bleeding site but may also demonstrate the vascular anatomy and the underlying cause, hereby directing further management and guiding therapeutic interventions, as will be illustrated in both of our cases.