Non-acid reflux disease is more complicated to diagnose than acid reflux because there is no acid to test or confirm as the problem. Gastroenterologist, Dr. Donald Castell, explains how the use of impedance measurements will detect the movement of any liquid in the esophagus by using a catheter placed through the nose. Dr. Castell also talks about research projects at the Medical University of South Carolina and clinical trials in progress for non-acid reflux disease.