White pyramid sign (kidney)

The white pyramid sign refers to the CT appearance of the medullary pyramids of the kidney which can be seen normally on unenhanced CT scans as high-attenuation triangular structures. 

Bilateral high-attenuation renal pyramids are an occasional incidental normal finding.  In contrast, unilateral appearance of white pyramids is subtle secondary sign suggestive of contralateral urinary tract obstruction.

Inspired signs
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Article information

rID: 28362
System: Urogenital
Section: Signs
Synonyms or Alternate Spellings:

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