Renal replacement lipomatosis: ultrasonography and computed tomography findings.

Replacement lipomatosis of the kidney is the result of severe atrophy or destruction of the renal parenchyma often caused by calculous disease with secondary marked proliferation of renal sinus, renal hilus, and perirenal fatty tissue. The diagnosis is difficult to establish with conventional radiographic methods. Although ultrasonography may show highly suggestive findings, computed tomography seems to be the most accurate method for demonstrating the distinctive features of replacement lipomatosis. Ultrasonographic and computed tomographic features in three cases of replacement lipomatosis of the kidney are reported.