Roux-en-O: How It Happens and How to Fix It.

The Roux-en-Y gastric bypass surgery improper technique can cause complications such as Roux-en-O, which is caused by an inadvertent anastomosis of the biliopancreatic limb to the gastric pouch, creating an "O" form to the bypass. We present intraoperative images of a mistaken Roux-en-Y's technique that caused the "O" anatomy and its successful reconstruction.