Fistulogram and ultrasound images of radio-cephalic fistula. a: Fistulogram after attempted angioplasty and before tPA infusion. Clot is seen in the venous aneurysm. b: Ultrasound demonstrates a persistent large clot in the venous aneurysm. c: Fistulogram of venous aneurysm one week after tPA infusion, demonstrating significant decrease in clot burden.