LearningRadiology

COPD
Emphysema

• Proteolytic enzymes secreted by polys and alveolar macrophages are normally inhibited by serum a-1 antitrypsin—but not in emphysema

Centrilobular (centriacinar) Emphysema (CLE)

• Involves upper lobes

• Major pathology is in respiratory bronchioles which become dilated

Alveolar ducts and sacs are spared

• Slightly more common than PLE

• Characteristically found in heavy smokers

Panlobular Emphysema (PLE)

• Usually affects lower lobes

• Involves overinflation and destruction of the alveolar sacs

• More common in aged patients than CLE

• More common in women than CLE (although both more common in men)

• Type associated with a-1 antitrypsin deficiency

Roentgenographic Patterns

Arterial Deficiency pattern (AD)

• Overinflation

• Flattened diaphragm

Increased Marking pattern (IM)

• Less or no overinflation

• Prominent pulmonary vasculature

• Almost always has pulmonary artery hypertension

• Centrilobular emphysema usually associated with Increased Marking pattern

CLEIM

• Panlobular emphysema usually associated with Arterial Deficiency pattern

PLEAD

• IM are Blue Bloaters; AD are Pink Puffers