ABSTRACT

Angiomyolipoma is the most common benign mesenchymal tumor of the kidney. Eighty percent of the patients present sporadically, where 20% occur a component of tuberous sclerosis or lymphangioleiomyomatosis. Angiomyolipomas contain varying amounts of mature fat, muscle and vessels, and are divided into fat-rich, fat-poor and fat-invisible types. Imaging findings are mainly based on revealing the macroscopic or microscopic fat content of the lesions. Angiomyolipomas present as confusing lesions if they are in types of fat-poor or fat-invisible, and the ones complicated by hemorrhage.