Chronic obstructive lung disease ( COPD) / Emphysema

Arcot Chandrasekhar, M.D.

Objectives:

  1. Diseases that are lumped together as COPD

  2. Pathology of emphysema and how it relates to image findings

  3. Image findings of hyper inflation

  4. Criteria for reporting emphysema

What is COPD?
Describe the characteristic pathologic changes in emphysema.

Emphysema

  • Note the clusters of dilated air spaces which are conspicuous in the middle and lower lobes of the right lung and the lower lobe of the left lung.
  • Both lungs are markedly enlarged.
Normal lungs.
What are the anticipated findings of COPD in CXR?

Hyperinflation

Hyperinflation of lungs occur in asthma, emphysema and chronic bronchitis.

Findings of hyperinflation are:

  • Dark lung fields.
  • Low set diaphragm in 11th or 12th posterior rib.
  • Heart is vertical and narrow. This is the result of downward push of diaphragm by lungs.
  • Flattened diaphragms in lateral chest.
  • Infra cardiac air: Left diaphragm is seen in its entirety.
  • Retrosternal air is increased.
  • Increased AP diameter.
What are the x-ray findings of emphysema?
  • Lungs are large and hyper inflated.
  • Signs of hyperinflation are:
    • Low set diaphragm
    • Flat diaphragm best determined by lateral chest
    • Hyper lucent lung fields
    • Increased AP diameter
    • Increased retrosternal air
    • Vertical heart
  • Signs of hyperinflation can be seen in emphysema, chronic bronchitis and asthma.
  • We can call it emphysema only when hyperinflation is associated with blebs and paucity of vascular markings in the outer third of the film.

Lateral chest is best to evaluate flattening of diaphragm, AP diameter and retrosternal air.

This lateral chest shows:

  • Increased AP diameter
  • Low set flat diaphragms
  • Hyper lucent lung fields
  • Increased retrosternal air encroaching on heart density
  • Multiple blebs: Avascular zones surrounded by thin wall
How to read suspected case of COPD
  1. Indicate the radio lucency of lung field. When it is darker that is when we consider COPD
  2. Identify all the signs of hyper inflation
  3. Look for signs of emphysema
    • avascularity in the peripheral one third of lung
    • zones of avascularity
    • bleb walls