The O'Reilly-Mullins Procedure is an operation intended to control the reflux of acid and stomach contents into the esophagus.  It also encompasses the repair of hiatal hernias.  Dr. Michael O'Reilly and Dr. Spencer Mullins developed a procedure for this purpose that achieves this goal with a minimum of side-effects, and with an outstanding durability and success rate.  Patients are often referred to the ASG for repair of anti-reflux operations such as the Nissen Fundoplication that have failed.