Tree-in-bud
In centrilobular nodules the recognition of 'tree-in-bud' is of value for narrowing the differential diagnosis.
Tree-in-bud describes the appearance of an irregular and often nodular branching structure, most easily identified in the lung periphery. 
It represents dilated and impacted (mucus or pus-filled) centrilobular bronchioles. #Diagnosis #Pathophys #Radiology #Pulmonary #CTChest #TreeInBud #Diagram #RadiologyAssistant