II. Definitions
- Pulmonary Bleb
- Small (<1-2 cm), thin walled (<1 mm) air containing spaces within the lung
- Pulmonary Bullae
- Larger (>1-2 cm) air containing spaces within the lung
- A Pulmonary Bulla may be a coalescence of Pulmonary Blebs
III. Pathophysiology
- Blebs and Bullae form as a result of subpleural alveolar rupture
IV. Risk Factors
- Tobacco Abuse
- Thin Patient
- COPD
V. Differential Diagnosis
- Pneumatocele (post-Pneumonia)
- Pneumothorax
- Cystic Bronchiectasis
- Cavitary Lung Disease
-
Cystic Lung Disease
- Lymphangioleiomyomatosis (LAM)
- Pulmonary Langerhans Cell Histiocytosis (PLCH)
- Birt-Hogg-Dube Syndrome (BHD)
- Lymphoid Interstitial Pneumonia (LIP)
VI. Complications
- Pneumothorax
- Bullae secondary infection
- Giant Bullous Emphysema (Vanishing Lung Syndrome)
- Large bullae, in some cases filling the entire hemithorax
- May impair lung function
VII. Resources
- Lung Bleb (Radiopaedia)