Crazy Paving is a appearance that is basically a linear network or reticular pattern in the crazy-paving sign is believed to result from a thickening of the interlobular septa, while areas of ground-glass opacity result from partial alveolar filling processes. Auntminnie or Classic association is with pulmonary alveolar proteinosis.
However, there are many etiologies of Crazy-paving sign such as:

* Pulmonary alveolar proteinosis
* Pneumocystis carinii pneumonia
* Mucinous bronchoalveolar carcinoma
* Sarcoidosis
* Lipoid pneumonia
* Adult respiratory distress syndrome
* Pulmonary hemorrhage
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