) CT Enterography There is no significant literature supporting the use of CT enterography in patients with overt UGIB. CT enterography requires the administration of large volumes of neutral oral contrast, which can mask GIB by dilution. Additionally, a large volume of oral contrast is often not tolerated by acutely ill patients. CT enterography is recommended by the Society of Abdominal Radiology Gastrointestinal Bleeding Disease-Focused Panel for patients with occult GIB or suspected small bowel bleeding, which often uses a multiphase technique [5]. CTA Abdomen and Pelvis With IV Contrast There is no significant literature supporting the use of CTA abdomen and pelvis with IV contrast only. The literature primarily reflects studies with CTA examinations without and with IV contrast. Dual-energy CT allows for the generation of virtual noncontrast images from a CTA data set. However, the use of these virtual unenhanced images in place of true unenhanced images is still limited to certain sites and remains a user-specific preference. So, they are not discussed in this document. CTA Abdomen and Pelvis Without and With IV Contrast CTA without and with IV contrast can help with the detection of a source for GIB [7,18]. CTA has been shown to be able to detect bleeding rates as slow as 0.3 mL/min, compared with 0.5 to 1.0 mL/min for conventional angiography and 0.2 mL/min for Tc-99m-labeled red blood cell (RBC) scintigraphy [19]. Faster acquisition, thin collimation, and greater availability have led to greater utilization of this study. The noncontrast images are useful for the detection of intraluminal high-attenuation material that may mimic intraluminal blood on contrast-enhanced images and may be necessary for the identification of sentinel clot [7]. The Society of Abdominal Radiology Gastrointestinal Bleeding Disease-Focused Panel published a consensus on CT imaging protocols for the detection of overt GIB [20].
Nonvariceal Upper Gastrointestinal Bleeding. ) CT Enterography There is no significant literature supporting the use of CT enterography in patients with overt UGIB. CT enterography requires the administration of large volumes of neutral oral contrast, which can mask GIB by dilution. Additionally, a large volume of oral contrast is often not tolerated by acutely ill patients. CT enterography is recommended by the Society of Abdominal Radiology Gastrointestinal Bleeding Disease-Focused Panel for patients with occult GIB or suspected small bowel bleeding, which often uses a multiphase technique [5]. CTA Abdomen and Pelvis With IV Contrast There is no significant literature supporting the use of CTA abdomen and pelvis with IV contrast only. The literature primarily reflects studies with CTA examinations without and with IV contrast. Dual-energy CT allows for the generation of virtual noncontrast images from a CTA data set. However, the use of these virtual unenhanced images in place of true unenhanced images is still limited to certain sites and remains a user-specific preference. So, they are not discussed in this document. CTA Abdomen and Pelvis Without and With IV Contrast CTA without and with IV contrast can help with the detection of a source for GIB [7,18]. CTA has been shown to be able to detect bleeding rates as slow as 0.3 mL/min, compared with 0.5 to 1.0 mL/min for conventional angiography and 0.2 mL/min for Tc-99m-labeled red blood cell (RBC) scintigraphy [19]. Faster acquisition, thin collimation, and greater availability have led to greater utilization of this study. The noncontrast images are useful for the detection of intraluminal high-attenuation material that may mimic intraluminal blood on contrast-enhanced images and may be necessary for the identification of sentinel clot [7]. The Society of Abdominal Radiology Gastrointestinal Bleeding Disease-Focused Panel published a consensus on CT imaging protocols for the detection of overt GIB [20].