Image-Enhanced Endoscopy (IEE) for Diagnosis of Non-Erosive Reflux Disease

When treating persistent heartburn from gastroesophageal reflux disease (GERD) that does not respond to conventional treatment (a class of medications called proton pump inhibitors), it is important to be able to distinguish between erosive GERD and non-erosive GERD (called NERD). Currently the best method the investigators have to make this distinction is esophageal 24-hour pH and impedance testing. The test involves inserting a catheter into the esophagus through the nose and having the catheter maintained in this position for 24 hours This test is invasive, can be uncomfortable, and it is expensive and time consuming. The investigators are hoping that image enhanced technology will identify characteristics that are found more commonly in patients with non-erosive GERD compared to controls and therefore provide evidence that may allow us to replace pH and impedance testing with the image enhanced endoscopy as the best way to diagnose NERD. Participants will be either patients undergoing an upper endoscopy as part of their standard clinical evaluation for heartburn that does not respond to PPIs or patients undergoing standard clinical evaluation endoscopy for other reasons.