Islet cell transplantation (IT) has had excellent success and the long-term durability depends upon an acceptable safety profile (1, 2). We describe an unusual and previously only briefly reported complication. A 47-year-old female had an uncomplicated ultrasound guided first IT. A second ultrasound guided IT 3 months later resulted in a bile duct puncture, but the procedure was otherwise successful. The transhepatic track was embolized with Avitene microfibrillary collagen paste (MedChem Products, Woburn, MA). The patient was discharged on the third postprocedural day with a normal ultrasound. The patient was readmitted 2 days later with right upper-quadrant abdominal pain. Ultrasound demonstrated intrahepatic biliary dilatation, an endoscopic retrograde cholangiopancreatography was unremarkable, and hepatic biochemistry demonstrated an obstructive pattern. A diagnosis of biliary colic secondary to intrabiliary hemorrhage was made. With the patient's symptoms and hepatic biochemistry resolving, she was discharged with a follow-up abdominal ultrasound in 2 weeks. The follow-up ultrasound revealed a 1.5-cm well-defined hypoechoic segment VIII region with turbulent flow on Doppler that appeared to be supplied by a branch of the hepatic artery and drained by a hepatic vein. At angiography, a segment VIII high-flow fistula between a third-order branch of the right hepatic artery and a second-order branch of the right portal vein was identified (Fig. 1A). The fistula was occluded with 1 cc of Histoacryl glue to prevent progression. A small corkscrew type artery remained patent after this first injection, so a second injection was performed with success (Fig. 1B, C). No significant procedural complications occurred.FIGURE 1.: (A) Selective catheterization of the hepatic artery proper reveals an arteriovenous fistula (white arrow) to a branch of the right portal vein (black arrow). Arrowhead indicates the catheter tip. (B) Unsubtracted angiogram demonstrates radiopaque Histoacryl glue (white arrow) of arteriovenous fistula. (C) Completion digital subtraction angiogram demonstrating complete occlusion of the fistula. White arrow indicates end of the contrast column.The procedural-related complications of a percutaneous approach for pancreatic islet cells infusion into the portal vein include hemoperitoneum, subcapsular hematoma, portal vein thrombosis, hemothorax, and gallbladder or biliary system puncture (1, 3–7). Hepatic artery to hepatic vein or portal vein fistulae are well described in the context of penetrating or blunt trauma, and after surgery or percutaneous liver biopsy (8–10). The options for fistula treatment are variable. It has been suggested that small peripheral asymptomatic fistulas be followed with ultrasound unless portal hypertension or increase in size occurs, in which case treatment is suggested to avoid complications (11). For a small, low-flow fistula, thrombogenic or sclerosing material such as alcohol or gel foam particles can be used. The preferred treatment for high-flow fistulas are embolization coils and wires (12). If interventional radiology techniques are not possible or unsuccessful, hepatic artery ligation or fistula resection could be performed. Our patient responded well to glue embolization. Another patient in our series has a small asymptomatic hepatic arteriovenous fistula that is being followed with ultrasound. A future option is to intervene if signs of progression develop. One other case of an arteriovenous fistula in the context of IT has been mentioned in the literature, but without details (4). With only two cases in our series of 88 patients and 169 transplant procedures, it is important to be aware of this complication and keep it in the differential diagnosis for post islet cell transplant abdominal pain. Amar A. Suchak Kevin O'Kelly Department of Radiology and Diagnostic Imaging University of Alberta Edmonton, Alberta, Canada F. Al Saif A. M. James Shapiro Department of Surgery University of Alberta Edmonton, Alberta, Canada Richard J. Owen Department of Radiology and Diagnostic Imaging University of Alberta Edmonton, Alberta, Canada