Value of arteriography in the evaluation of a sonolucent pancreatic mass.

A pseudoaneurysm of the pancreaticoduodenal artery secondary to chronic pancreatitis was erroneously diagnosed as a pancreatic pseudocyst by abdominal plain films, barium gastrointestinal studies, and abdominal ultrasound. Because of the operative findings, it was necessary to interrupt surgery undertaken to drain the presumed pseudocyst. Angiography is strongly recommended as a preoperative study in patients with sonolucent pancreatic masses to distinguish pseudoaneurysms of pancreatic vessels from pseudocyts.