High Resolution CT > Findings > Centrilobular Nodules

CENTRILOBULAR NODULES

Nodules as small as 1-2 mm in diameter can be detected by HRCT. Nodules can be classified according to their appearance such as well-defined (likely interstitial) or ill-defined (likely air-space) or classified according to their distribution in relation to other lung structures (i.e. perilymphatic, random, or centrilobular).

Centrilobular nodules are often centered 5-10 mm from the pleural surface and do not occur in relation to interlobular septa. Typically centrilobular nodules are ill-defined, but can be well-defined. Centrilobular nodules can be identified in close association with centrilobular structures (i.e. small pulmonary artery branches).