Arteriovenous malformation simulating Meckel's diverticulum on 99mTc-pertechnetate abdominal scintigraphy

Area of Science:

• Nuclear medicine imaging
• Gastrointestinal diagnostics
• Interventional radiology

Background:

• Chronic gastrointestinal bleeding necessitates accurate diagnosis.
• Meckel's diverticulum is a common cause of obscure GI bleeding.
• Technetium-99m pertechnetate scintigraphy is a standard diagnostic tool.

Observation:

• A 67-year-old woman presented with chronic gastrointestinal bleeding.
• Scintigraphy revealed increased activity in the right lower quadrant, concurrent with gastric visualization.
• This finding was initially suspected to be a Meckel's diverticulum.

Findings:

• Superior mesenteric angiography identified a small arteriovenous malformation as the bleeding source.
• Laparotomy confirmed the arteriovenous malformation as the cause of bleeding.
• The scintigraphy finding was a false positive for Meckel's diverticulum.

Implications:

• This case highlights the potential for false-positive results in Meckel's diverticulum scintigraphy.
• Comparative evaluation of early and late scintigraphic images is essential for accurate diagnosis.
• Arteriovenous malformations should be considered in the differential diagnosis of gastrointestinal bleeding when scintigraphy is equivocal.