Fig. 2From: Enlarged mediastinal air cyst in a patient with bronchial diverticula localized in the left main bronchus: a case report with surgical and bronchoscopic findingsBronchoscopic image showing the left main bronchus. a The reddish membranous portion is concave, thereby resulting in a round-shaped lumen. b Bubbling from slits or indentations of the bronchial mucosa (arrow)Back to article page