Renal milk of calcium cysts refer to the appearance of a calcium precipitate found either within a calyceal diverticulum, that has lost communication with the collecting system, or within a simple renal cyst.
Renal milk of calcium cysts are typically asymptomatic.
Renal milk of calcium cysts are more common in the upper renal pole.
- on erect or decubitus films, renal milk of calcium cysts have a characteristic crescentic opacity with a sharp upper border
- will change shape to a more oval-shaped opacity on supine projections
- dependent echogenic material within a hypoechoic cyst that demonstrates reverberation artefact
- posterior shadowing is present when large volumes of milk of calcium are present
Treatment and prognosis
Considered an incidental benign finding that does not require further treatment unless symptomatic.
On supine plain radiographs, a renal milk of calcium cyst may be mistaken for a renal calculus. Milk of calcium can also occur within the gallbladder.
- 1. Yeh HC, Mitty HA, Halton K et-al. Milk of calcium in renal cysts: new sonographic features. J Ultrasound Med. 1992;11 (5): 195-203. Pubmed citation
- 2. MURRAY R. American Journal of Roentgenology. 1971;113 (3): . doi:10.2214/ajr.113.3.455
- 3. HENKEN EM. "MILK OF CALCIUM" IN A RENAL CYST: REPORT OF A CASE. Radiology. 1965;84 (2): 276-8. doi:10.1148/84.2.276 - Pubmed citation
- 4. Barbaric ZL. Principles of genitourinary radiology. Thieme. ISBN:0865774935. Read it at Google Books - Find it at Amazon
- 5. Baxter G, Sidhu P. Ultrasound of the Urogenital System. TIS. ISBN:B005KMEWS4. Read it at Google Books - Find it at Amazon
- 6. Chopra S. Genitourinary Imaging (Radcase). TNY. ISBN:B005WJJLIG. Read it at Google Books - Find it at Amazon