An esophageal ring is exactly what it says. It is a fixed ring of fibrous tissue around the lower esophagus, also called Schatzki's ring after the doctor who first described it. It is often associated with a hiatus hernia which, in turn, causes reflux of stomach acid back into the esophagus. It never becomes malignant. No one knows for sure why they develop. Fortunately, they can be readily treated by simple dilation, which stretches and generally breaks this constricting ring, thereby allowing food to pass and relieving the feeling of food holdup.