Parenchymal bands are a HRCT finding. They can be commonly encountered among patients with asbestosis.
They are typically over 2 cm in length (up to 5 cm), 1-3 mm thick and run through the lung parenchyma and usually extend from a visceral pleural surface 6. They are formed in a number of ways 1:
They are thought to reflect pleuroparenchymal fibrosis and are usually associated with distortion of the lung architecture.
- thickening of interlobular septae of a number of adjacent secondary pulmonary lobules
- fibrosis of peribronchovascular interstitium
Parenchymal bands are encountered in a wide range of pulmonary diseases and represent one of the many end-stage fibrotic findings. To mention a few causes:
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