Figure 4

Bronchoscopy (a): the tip of the scope is located just beyond the carina, at the level of the right mainstem bronchus. The right cranial lobar bronchus is at 11 o' clock, the right middle bronchus is at 7 o'clock and both the caudal and accessory lobar bronchi are at 6 o'clock. The right cranial bronchus is occluded by a serosanguinous fluid and there is narrowing and occlusion of its lumen even after the introduction of a small amount of sterile saline. The other bronchi are patent.(b): the mucosa of the right cranial bronchus is folded, with twisting of the folds in a clockwise direction.