Radiological appearance of pulmonary venous hypertension

Chest radiology changes vary with respect to the developing pulmonary hypertension.

Early changes include Kerley B lines.

Later changes include:

• fluffy appearance of horizontal veins in the lower zones. These veins are dilated due to increased venous pressure and may be mistaken for Kerley B lines.
  
  
• upper lobe diversion - both a visual illusion and a real phenomenon:
  • the increased venous pressure causes transudate to drain into the interstitium and so reduces the contrast between fluid filled blood vessels and the background
  • the flow to the veins in the upper lobes is increased as a result of the more voluminous interstitium putting pressure on veins in the lower zones
    
    
• peribronchial cuffing
  
  
• pleural effusion - occurs as a result of transudative fluid within the pleural cavity