Constrictions of oesophagus

The esophagus has 4 areas where the lumen is narrow compared to the rest of the oesphagus. They are:

1. Beginning of oesophagus (pharyngoesophageal junction) – 6 inches from incisor teeth
2. level where arch of aorta crosses oesophagus – 9 inches from incisor teeth
3. At the level where the left main bronchus crosses oesophagus – 11 inches from incisor teeth
4. At the end where it pierces diaphragm – 15 inches from incisor teeth

The distance from incisor teeth should be taken into consideration when passing endoscopes.