Gastrointestinal ImagingE3331. Pancreatic Arteriovenous Malformation: A Case Study
Murphy L, De Jesus H, Hudson C, Spieler B, Cajigas-Loyola S. Louisiana State University, New Orleans, LA
Address correspondence to L. Murphy (firstname.lastname@example.org)
Background Information: A 37-year-old man with recent diagnosis of chronic hepatitis C presented for sonography with liver fibrosis staging. Incidental visualization of a pancreatic mass led to further evaluation with triple-phase CT and to the diagnosis of a pancreatic arteriovenous malformation. Of the fewer than 100 reported cases of pancreatic arteriovenous malformation, more than 80% are diagnosed during evaluation of patients experiencing symptoms such as abdominal pain, gastrointestinal bleeding, and jaundice.
Educational Goals/Teaching Points: Vascular malformations are commonly visualized and are often inappropriately diagnosed in reports as a simple hemangioma or arteriovenous malformation. However, the International Society for the study of Vascular Anomalies provides a useful classification system for vascular tumors and malformations. These distinctions are critical in regard to determining possible need for follow-up or intervention and subsequent options for treatment.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques: Arteriovenous malformations are the confluence of tortuous vessels that form a shunt due to the absence of intervening capillaries. Noninvasive sonography with color Doppler and contrast-enhanced CT and MRI are typically used in a stepwise fashion to diagnose and assess the extent of the lesion. Proper diagnosis and radiographic evaluation of a pancreatic arteriovenous malformation is imperative due to the anatomic relationships and likely involvement of large mesenteric vessels, tendency to cause bleeding, and shunting of portosystemic blood volume with increasing size.
Conclusion: Pancreatic arteriovenous malformation is typically rare on the list of differential diagnoses for a hypervascular lesion at the pancreatic head. Progression of this patient’s chronic hepatitis C increases his likelihood of portosystemic shunting, and gastrointestinal bleeding. The presence of this vascular malformation without confirmation of stability further increases that risk. Characterization of this lesion is essential to planning interventional and surgical procedures if the patient becomes symptomatic and can prompt early treatment of comorbidities, such as chronic hepatitis C, that increase that risk.