[The application of sonography in the differential diagnosis of space-occupying renal lesions (author's transl)].

Two dimensional ultrasound echography is a reliable method for demonstrating the topography of retroperitoneal space-occupoing lesions which causes little inconvenience to the patient. This is particularly the case in the upper abdomen, where the differentiation between renal, suprarenal, pancreatic and splenic lesions has been difficult. The criteria for the differential diagnosis of sonographic findings are described and discussed. Echography should be used before invasive methods, particularly angiography, are employed.