The Role of CT-Angiography in the Acute Gastrointestinal Bleeding: A Pictorial Essay of Active and Obscure Findings

Abstract

Gastrointestinal bleeding is a potentially life-threatening abdominal emergency that remains a common cause of hospitalisation. Although 80–85% of cases of gastrointestinal bleeding resolve spontaneously, it can result in massive haemorrhage and death. The presentation of gastrointestinal bleeding can range from asymptomatic or mildly ill patients requiring only conservative treatments to severely ill patients requiring immediate intervention. Identifying the source of the bleeding can be difficult due to the wide range of potential causes, the length of the gastrointestinal tract and the intermittent nature of the bleeding. The diagnostic and therapeutic approach is fully dependent on the nature of the bleeding and the patient’s haemodynamic status. Radiologists should be aware of the appropriate uses of computed tomography angiography and other imaging modalities in patients with acute gastrointestinal bleeding, as well as the semiotics of bleeding and diagnostic pitfalls in order to appropriately diagnose and manage these patients. The learning objective of this review is to illustrate the computed tomography angiography technique, including the potential role of dual-energy computed tomography angiography, also highlighting the tips and tricks to identify the most common and uncommon features of acute gastrointestinal bleeding and its obscure form.

Colonoscopic Findings in Patients with Bleeding Per-rectum in Colonoscopy Center at Rizgary Teaching Hospital, Erbil, Iraq

“…Acute bleeding per rectum will cease spontaneously in about 80% of patients [5] and in a study done by Farell et al [16] the bleeding stopped spontaneously in about 83% of patients, while in another study, bleeding per rectum will cease spontaneously in 85% of patients [17], and in a study done by Boley SJ et al [18]; the acute bleeding stopped in 90% of the patients spontaneously. Only 17 (18.7%) of the patients in our study had active bleeding stop after conservahttp://doi.org/10.33091/amj.2023.178354 tive treatment prior to the endoscopy.…”

“…The chronic type manifests as occult blood in the stool, iron deficiency anemia, intermittent attacks of melena, hematochezia, or maroon stools, or visible small amounts of rectal bleeding [4]. Therefore, LGIB can be classified into two forms; occult or revealed hemorrhage [5].…”

Extravasated contrast volumetric assessment on computed tomography angiography in gastrointestinal bleeding: A useful predictor of positive angiographic findings

“…In order to perform an effective TAE, CTA plays a critical role in the detection of bleeding site, delineating the underlying vascular anatomy and providing information about possible vascular variants, with a reported sensitivity of nearly 100%[ 2 , 35 ]. Furthermore, due to the relatively high rate of intestinal ischemia following TAE in lower GIB (up to 4% of cases), especially in cases of blind embolization, CTA positivity is crucial before performing TAE[ 19 ].…”

“…Despite that CTA has been reported to be more sensitive than catheter angiography in the detection of active GIB signs, the need for angiography should not be exclusively based on a positive CTA as several patient related factors have to be considered[ 19 ]. Furthermore, a large portion of GIB cases detected by CTA are occult on catheter angiography[ 21 ].…”

Practical Aspects of Upper Gastrointestinal Bleeding in Children

“…This method can locate the source of bleeding, differentiate venous bleeding from arterial bleeding, and is usually available in emergency settings. In UGB this method is considered a second-line choice in patients with negative endoscopy or in cases where the bleeding source was not identified during an endoscopy [12].…”