Abnormal tracheal morphology Diverticulosis of trachea Tracheal diverticulum SNOMEDCT_US:14011008 UMLS:C0340213 Paratracheal air cyst HP:0006509 Tracheal diverticulosis Tracheocele Tracheal diverticula are blind-ended outpouchings arising from the trachea. They are usually an incidental finding. Occasionally they can mimic pneumomediastinum. Tracheal diverticula are either congenital or acquired, in the latter case the most common causes are prolonged increased intraluminal pressure, e.g. chronic cough, COPD, tracheomalacia, and iatrogenic (e.g. post-surgical).