Randall's plaques are described as subepithelial calcification of the renal papilla which are <2 mm in their greatest dimension. They act as an anchor for calcium oxalate crystals and are considered to be a predisposing factor for renal stone formation.
Usually asymptomatic and may not always result in stone formation in the course of time.
In any imaging modality, these calcifications are seen as tiny foci with at least 50% of the surface covered by renal parenchyma.
Presence of urine all around the foci may point to the diagnosis of calyceal microlithiasis which are seen within the calyces.
History and etymology
Originally described by Alexander Randall (1883-1951) , an American urologist, in 1937 as part of a postmortem case series using a hand lens.