Oesophageal narrowing. Endoscopic view of a narrowing (stricture or stenosis, centre) of the oesophagus, caused by gastroesophageal reflux disease (GORD). GORD (reflux oesophagitis) occurs when stomach contents leak back (reflux) into the oesophagus. The acid in the stomach contents damages the mucosal layer (lining) of the oesophagus. The resultant cell damage causes the lining to harden and become less elastic. This results in the narrowing of the passage, making it difficult for food to pass through.