This document discusses tracheal anatomy and disorders. It provides details on the structure and dimensions of the trachea, as well as its relations to surrounding structures. Various congenital abnormalities, injuries, and diseases that can cause tracheal narrowing or stenosis are described. Post-intubation stenosis is highlighted as a common cause of acquired tracheal narrowing, often appearing as eccentric or concentric soft tissue narrowing on imaging while the cartilage remains intact.