A bulla in a lung lobe is an air-filled space measuring 1 cm or more in diameter within the lung, resulting from the destructive effects of emphysema on lung tissue.
Understanding bullae involves looking at their characteristics and how they form.
Defining a Lung Bulla
Based on the provided reference:
- A bulla is an air-filled space within the lung.
- It is specifically defined by its size, being 1 cm in diameter or larger.
- Its formation is attributed to emphysematous destruction of the lung parenchyma (the functional tissue of the lung).
This destructive process, characteristic of emphysema, leads to the breakdown of the tiny air sacs (alveoli) and surrounding structures in the lung. As these air spaces merge and enlarge, they can form bullae. These large air pockets don't function in oxygen exchange like healthy alveoli and can sometimes cause breathing difficulties or other complications.
Key Characteristics of Lung Bullae
Here's a simple breakdown:
- Location: Found within the lung lobes.
- Size: At least 1 cm in diameter.
- Composition: Filled with air.
- Cause: Developed due to the destruction of lung tissue associated with emphysema.
While the term "bulla" strictly refers to spaces 1 cm or larger, smaller spaces caused by similar destruction are often called blebs, though the terminology can sometimes overlap or be used differently depending on the context. However, the crucial point for a bulla is its size and the underlying emphysematous change.
