The Golf Ball–on-Tee Sign

The golf ball–on-tee sign is seen during excretory urography and appears as a contrast agent–filled cavity (the golf ball) that lies adjacent to a blunted calyx (the tee).

Excretory urogram (frontal view) displaying the left side of the collecting system shows contrast material in a large papillary cavity, the “golf ball” (∗). A blunted calyx, the “tee,” is adjacen (arrow).                          

Photograph of a golf ball on a tee.

The collecting tubules within the medullary pyramid come together to form the papillary ducts that penetrate the papillary tip and drain into a calyx. Normally, individual collecting tubules are not visualized; rather, the normal papilla has a distinctive blush that fades with time. In papillary necrosis, however, central necrosis and sloughing of the papilla create a cavity, which is occasionally large, that fills with contrast material and communicates with the calyceal concavity. Thus, the golf ball–on-tee sign is created, indicating necrosis.  

The common etiology of papillary necrosis can be conveniently remembered with Dunnick's mnemonic NSAID: nonsteroidal anti-inflammatory medications, sickle cell hemoglobinopathies, analgesic nephropathy (specifically aspirin and phenacetin), infection (specifically tuberculosis), and diabetes. Some less-common causes include renal vein thrombosis, hypotension, and obstructive uropathy. The papillary necrosis seen in tuberculosis and severe pyelonephritis is a direct result of the infection.