The calyceal crescent sign refers to the early IVP appearance of markedly dilated renal calyces. It is formed by contrast outlining the collecting ducts and ducts of Bellini which are distorted by the associated enlarged calyces. This appearance can be appreciated on IVP and CT contrast excretory phase.
It is a marker of elevated pressure within the renal pelvis and is an important indicator as to whether the renal function is recoverable.
- 1. Khanna Geetika. “The Calyceal Crescent Sign.” Radiology 236, no. 2 (August 1, 2005): 653-654. doi:10.1148/radiol.2362031411.
- 2. Dyer RB, Chen MY, Zagoria RJ. Classic signs in uroradiology. Radiographics. 2004;24 Suppl 1 (suppl 1): S247-80. Radiographics (full text) - doi:10.1148/rg.24si045509 - Pubmed citation