A case of tracheobronchopathia ostochondorplastica

Key message Tracheobronchopathia osteochondroplastica (TO) is a disorder caused by the accumulation of calcium phosphate in the submucosa of large airways. Benign proliferation of bone and cartilage lead to the narrowing of airways. Bronchoscopy is the diagnostic test for TO. It shows characteristic smooth nodules emerging from tracheal rings that never involves the posterior membranous wall.