Teenager with an incidental renal cyst containing calcium on US

CT of renal milk of calcium cyst
Coronal (above left), sagittal (above right) and axial (below left) CT without contrast of the abdomen show a round low density lesion in the inferior pole of the right kidney that has a cresenteric calcification next to the wall of its inferior-posterior aspect. Axial CT with contrast of the abdomen (below right) more clearly shows the calcification next to the wall of the inferior-posterior aspect of the low density lesion in the kidney.

The diagnosis was renal milk of calcium cyst.