crazy paving appearance

crazy paving appearance

Dermatology
A descriptive term for the mottled pigmented and depigmented skin, which is reminiscent of cracked pavement and angulated paving stones, which may be seen in children suffering from the kwashiorkor-marasmus complex.
 
Imaging
A term referring to a fine reticular (septal) pattern superimposed on areas of ground-glass opacity on high-resolution CT of the lungs. Crazy paving was once regarded as characteristic of alveolar proteinosis, but subsequently identified in bronchiolitis obliterans-organising pneumonia/cryptogenic-organising pneumonia (BOOP/COP), infection (PCP/PJP, viral, Mycoplasma, bacterial), neoplasm (bronchioloalveolar carcinoma), non-specific interstitial pneumonia (NSIP), pulmonary oedema (heart failure, ARDS, AIP), pulmonary haemorrhage, and sarcoidosis.

Pathology
(1) A term referring to the complex, disorderly cell arrangement seen in hyalinising trabecular adenoma of the thyroid, which is characterised by prominent diffuse peripheral staining of tumour cells, with lesser staining of the rest of the cytoplasm.
(2) A term of art referring to the appearance of “thin colloid” with cracking artefact, which is seen in aspiration cytology specimens from follicular thyroid neoplasia.