One Anastomosis Gastric Bypass 
(AKA omega, mini bypass)

This procedure is performed though 5 small incisions, 5mm - 12mm in size.  It involves the division of the stomach into a small pouch which is then joined (anastomosed) to the small bowel.  A second join is then formed small bowel to small bowel.  This procedure produces significant changes in gastro-intestinal hormones leading to significant weight loss.  Whilst there are some increased risks of this procedure over other weight loss surgeries, it remains a popular and effective procedure for weight loss and treatment of reflux disease.