Chronic hypersensitivity pneumonitis
The key findings in chronic hypersensitivity pneumonitis are:
Mosaic pattern with areas of ground-glass atenuation and areas of low attenuation.
Fibrosis and parenchymal distortion in a mid zone distribution.
On the left a patient with chronic hypersensitivity pneumonitis. 
The HRCT shows a mosaic pattern with hyperaerated secondary nodules and secondry nodules of increased attenuation. 
Additionally there is septal and intralobular reticular thickening, indicating already existing irreversible fibrosis. #Clinical #Radiology #CXR #CTChest #Hypersensitivity #Pneumonitis #HypersensitivityPneumonitis #Chronic #Fibrosis #RadiologyAssistant