Congenital Arteriovenous Malformation of the Pancreas : Its Diagnostic Features on Images

Summary: To analyze diagnostic features on images of congenital arteriovenous malformation (AVM) of the pancreas, we analyzed the diagnostic findings in six patients with the disease, using gray-scale ultrasonography (US), color Doppler US, computed tomography, and angiography and analyzed previously reported cases. AVM characteristic findings on images were multiple, small hypoechoic nodules on US, mosaic appearance of the lesion and pulsatile wave form in the portal vein on color Doppler US, conglomerated small nodular enhancement of the lesion and early appearance of the portal vein on CT, and a racemose network and early appearance of the portal vein on angiography. Five of the six patients underwent surgery, and all resected specimens were histologically found to be AVMs of the pancreas; however, one with developed portal hypertension at surgery died of repeated bleeding from esophageal varices. From analysis of total of 35 cases including our six cases, a mosaic appearance of the lesion was found in 100% and a pulsatile wave form in the portal vein in 77.8% on color Doppler US. Color Doppler US is noninvasive and useful for detecting congenital AVM of the pancreas at an early stage, preventing the portal hypertension causing esophageal varices and their rupture.