THE INDICATIONS for visualization of the kidneys in the patient with renal failure are (1) to exclude a remedial cause of renal failure (eg, hydronephrosis), (2) to evaluate renal size, (3) to determine kidney position for biopsy, and (4) to confirm a specific disease entity (eg, polycystic kidneys).
Sonography
Sonography is a noninvasive diagnostic imaging modality that is ideally suited for the examination of the kidneys of the patient in renal failure.1-5 The procedure is applicable to all patients irrespective of the degree of renal failure, since renal function is not necessary for visualization. The technique is sufficiently accurate to be relied on as the initial and, at many times, the only diagnostic procedure. The demonstration of the anatomy is not as good as with urography but is sufficiently finite to identify accurately an obstructive uropathy as the cause of renal failure. Fine caliceal detail cannot be resolved, and