Tracheo-Esophageal Stripe
The posterior wall of trachea (T) and the anterior wall of esophagus (E) are in close contact and form the tracheo-esophageal stripe in the lateral view (arrow).
When it is wider than __ mm, it is abnormal.
Common causes for thickening of tracheo-esophageal stripe are esophageal disease and nodal enlargement.