Sonography achieves an accuracy of 93% (n = 55/59) in the localisation of space-occupying lesions in the kidney. Since the method is somewhat laborious, ultra sound, in the form of a slow B-scan, cannot be regarded as an alternative to radiology with an accuracy of 97% (n = 57/59). 2. For a pathological diagnosis, particularly in the distinction between tumours and cysts, sonography, with an accuracy of 98% (n = 54/55) is markedly better than radiology with an accuracy of 50% (n = 21/42). Sonography is approximately equal to angiography, which has an accuracy of 97% (n = 69/71). 3. Sonography is useful and is indicated for: a) the investigation of non-functioning kidneys, b) patients in whom radiographic contrast media are contra-indicated, and c) for puncture of renal cysts. (F. St.).
