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Localization of small bowel bleeding by arterial injection of Tc-99m-labeled RBC.
1Department of Radiology, Musashino Red Cross Hospital, Japan. saito-k@mxy.mesh.ne.jp
Annals of Nuclear Medicine
|August 6, 1999
Summary
Technetium-99m-labeled red blood cell (Tc-99m-RBC) scintigraphy via superior mesenteric artery (SMA) injection accurately located small bowel bleeding. This arterial injection method improved diagnostic precision over conventional intravenous techniques for obscure gastrointestinal hemorrhage.
Area of Science:
- Nuclear medicine
- Gastroenterology
- Diagnostic imaging
Background:
- Small bowel bleeding presents a diagnostic challenge, often with negative conventional endoscopic findings.
- Melena in a 79-year-old male prompted investigation for obscure gastrointestinal bleeding.
Observation:
- Technetium-99m-labeled red blood cell (Tc-99m-RBC) scintigraphy was performed using arterial injection of the radiotracer into the superior mesenteric artery (SMA).
- Angiography initially showed no bleeding, but Tc-99m-RBC scintigraphy revealed extravasation in the ileum.
- Comparing the 2-minute arterial injection scintigram with the late capillary phase of balloon-occluded angiography enhanced anatomical localization.
Findings:
- Arterial Tc-99m-RBC scintigraphy via SMA successfully identified an ileal bleeding site.
- This technique demonstrated superior accuracy in pinpointing the small bowel hemorrhage compared to intravenous Tc-99m-RBC scintigraphy.
Implications:
- Direct arterial injection of radiotracers offers improved accuracy for Tc-99m-RBC scintigraphy in diagnosing small bowel bleeding.
- This method enhances anatomical precision, aiding in the management of obscure gastrointestinal bleeding when other modalities fail.
