The trachea, or windpipe in layman’s terminology, begins on its upper end just below the larynx and extends inferiorly into the chest where it splits into the right and left mainstem bronchi; delivering inspired air to the right and left lungs, respectively.
The tracheal rings comprise approximately two-thirds of the circumference of the trachea, anteriorly and laterally. The remaining posterior one-third “membranous” tracheal mucosa is the anterior surface of the “party wall” it shares with the esophagus.
Photos:
Trachea (1 of 2)
View from just below the vocal cords. Note the u-shaped cartilaginous tracheal rings that give the trachea some firmness and resistance to collapse. The membranous third of the circumference puts a flat "lid" on the trachea, but can bulge inward when a person coughs.
Trachea (2 of 2)
View from the middle of the trachea in a different patient. Here the tracheal rings are shaped more like an “o” but the top of the “o” is completed by the membranous tracheal wall marked by the blue line. Also, the carina is seen distally and marked by an "x". This is where the trachea divides into right and left mainstem bronchi.
Trachea (1 of 1)
Radiographic view at the upper chest level. The horseshoe-shaped anterior segment of the trachea’s wall, two-thirds of the total circumference, is the trachea’s cartilaginous component. The posterior one-third is the membranous trachea, which also constitutes the anterior one-third of the esophagus, and is also called the tracheoesophageal party wall. The esophagus is dilated with air; this patient has undergone a total laryngectomy.
View into mid-trachea, diagnosis unknown (1 of 4)
View into the middle of the trachea in a man being evaluated for an unrelated problem. Note the remarkable projections (compare with normal trachea elsewhere on site). At initial examination the diagnosis was not known. The 'X' in subsequent photos marks the same place on the carina.
Spicules found in the tracheal wall (2 of 4)
A little farther down the trachea, and a closer view of the spicules projecting from the tracheal wall, whose nature at this examination was still unknown.
Diagnosis revealed (3 of 4)
View within the trachea just above the carina, where the trachea divides into right and left mainstem bronchi. Attempted biopsy revealed the extremely hard and unyielding nature of the projections, subsequently shown to be “bone.” Literature review revealed the diagnosis of tracheobronchopathia osteochochondroplastica, which essentially means “disease in trachea and bronchi due to bony change/ growth in cartilage rings.”
Biopsy reveals bone tissue (4 of 4)
Attempt to biopsy these projections with a flexible scope was unsuccessful due to their bony nature. Biopsy in the operating room made the diagnosis by revealing bone tissue. Copy and paste the link below to view the definition of tracheobronchopathia osteochochondroplastica: http://www.ncbi.nlm.nih.gov/pubmed/25013916
Mild tracheobronchopathia osteochochondroplastica (1 of 2)
A milder expression of this disorder. This person has been followed for years for a different problem, so these are incidental findings. Across the years, there has been no change in the lesions seen here in the trachea.