Image diagnosis of renal angiomyolipoma

Five cases of renal angiomyolipoma without associated tuberous sclerosis were diagnosed by urography, ultrasonography, computed tomography (CT), and angiography before the operation. Urography demonstrated the existence of the mass in all cases without providing the pathological nature of the mass. Although ultrasonography revealed an internal high echo of angiomyolipoma in all cases, it was difficult to differentiate from other echogenic tumors. CT which identified fat density in the tumor was very valuable in making the accurate diagnosis in all cases. A small fatty area in the tumor and the association of the tumor of a different nature were pitfalls of CT diagnosis of renal angiomyolipoma. Ultrasonography and/or angiography complemented the accurate diagnosis in such cases. CT also identified the characteristic aneurysmal dilatation in two cases. The growth of the tumor was exophytic in all cases. The bleeding from the tumor was found in three symptomatic cases. The location and the extent of the bleeding were accurately demonstrated by CT and ultrasonography. (author)