[The accuracy of sonography in the diagnosis of renal disease (author's transl)].

The accuracy of sonography in the diagnosis of spaceoccupying renal lesions was evaluated by a retrospective study of 221 patients. There were 15 incorrect diagnoses. In 93% of cases the sonographic diagnosis was correct. Erroneous diagnoses, which would have been difficult to avoid even retrospectively, were usually due to complex lesions which were partly cystic and partly solid. In order to differentiate cysts from solid lesions it is considered essential to use both A- and B-scans and step-wise variations of sound energy. These results emphasise the great value of ultrasound in the differentiation of renal abnormalities. Sonography should be used, during the clinical work up, after the urogram, but before angiography or other invasive methods are employed.