How Are Blebs Formed on the Lung?

A bleb is caused by alveolar rupture, which allows air to travel through the interlobular septum that divides the secondary pulmonary lobules to the subpleural region. The subpleural region is displaced, and a subpleural emphysematous vesicle (i.e., a bleb) is thus formed.

Why do blebs form on lungs?

Blebs are thought to occur as a result of subpleural alveolar rupture, due to overload of the elastic fibers. Pulmonary bullae are, like blebs, cystic air spaces that have an imperceptible wall (less than 1 mm).

How common are lung blebs?

This condition occurs in 7.4 to 18 per 100,000 men each year and 1.2 to 6 per 100,000 women each year.