Gastrointestinal Bleeding Scintigraphy in the Early 21st Century

Abstract

Gastrointestinal bleeding scintigraphy performed with (99m)Tc-labeled autologous erythrocytes or historically with (99m)Tc-sulfur colloid has been a clinically useful tool since the 1970s. This article reviews the history of the techniques, the different methods of radiolabeling erythrocytes, the procedure, useful indications, diagnostic accuracy, the use of SPECT/CT and CT angiography to evaluate gastrointestinal bleeding, and Meckel diverticulum imaging. The causes of pediatric bleeding are discussed by age.

Inverted Meckel’s diverticulum: Two case reports and a review of the literature

“…Intermittent and/or small amounts of GI bleeding can be easily detected by Tc 99m RBC scintigraphy, where the minimum detectable bleeding rate was reported as 0.05-0.2 mL/min; relatively stable persistence in the circulation made it possible to monitor patients with intermittent bleeding[ 11 ]. Scintigraphy could have been used to locate the bleeding focus in the first case.…”

“…CT angiography can be considered if the GI bleeding is active. The detection limit of CT angiography for active bleeding was 0.3 mL/min in porcine models[ 11 ]. Our cases were regarded as having chronic and intermittent GI bleeding, not active bleeding.…”

A Pelvic Meckel Diverticulum Mimicking the Urinary Bladder on a Meckel Scan

“…Bleeding is more common in children but also occurs in adults. In some cases, it can be severe or even life-threatening (2,3). Although a Meckel diverticulum is usually in the right lower quadrant of the abdomen, its location can be anywhere in the abdomen or pelvis (4).…”

Two decades of SPECT/CT – the coming of age of a technology: An updated review of literature evidence

“…Timing of 99m Tc-RBC SPECT/CT acquisition needs further evaluation. There is also concern that during the relatively long SPECT/CT acquisition, patient motion or bowel artefacts can affect correct localization of the bleeding site [239,240].…”