Crazy paving refers to a pattern seen on computed tomography of the chest, involving lobular

septal In biology, a septum (Latin for ''something that encloses''; plural septa) is a wall, dividing a cavity or structure into smaller ones. A cavity or structure divided in this way may be referred to as septate. Examples Human anatomy * Interatr ...

thickening with variable alveolar filling. The finding is seen in

pulmonary alveolar proteinosis Pulmonary alveolar proteinosis (PAP) is a rare lung disorder characterized by an abnormal accumulation of surfactant-derived lipoprotein compounds within the alveoli of the lung. The accumulated substances interfere with the normal gas exchange and ...

, and other diseases. Its name comes from its resemblance to irregular

paving stone Pavement, in construction, is an outdoor floor or superficial surface covering. Paving materials include asphalt, concrete, stones such as flagstone, cobblestone, and setts, artificial stone, bricks, tiles, and sometimes wood. In landscape archite ...

s, called crazy pavings.

Causes

There are variety of causes for crazy paving patterns: infection, cancer, blood related disorders, diseases caused by inhalation of particles, and

idiopathic disease An idiopathic disease is any disease with an unknown cause or mechanism of apparent spontaneous origin. From Greek ἴδιος ''idios'' "one's own" and πάθος ''pathos'' "suffering", ''idiopathy'' means approximately "a disease of its own kin ...

. Specific lung disorders that can cause such patterns are: pneumocystis pneumonia, mucinous bronchioloalveolar carcinoma, pulmonary alveolar proteinosis,

sarcoidosis Sarcoidosis (also known as ''Besnier-Boeck-Schaumann disease'') is a disease involving abnormal collections of inflammatory cells that form lumps known as granulomata. The disease usually begins in the lungs, skin, or lymph nodes. Less commonly a ...

, nonspecific interstitial pneumonia,

organizing pneumonia Cryptogenic organizing pneumonia (COP), formerly known as bronchiolitis obliterans organizing pneumonia (BOOP), is an inflammation of the bronchioles ( bronchiolitis) and surrounding tissue in the lungs. It is a form of idiopathic interstitial pn ...

, exogenous lipoid pneumonia, adult respiratory distress syndrome, and pulmonary hemorrhage syndromes.

References

Radiologic signs Respiratory system imaging