Intravenous Urography in the Patient with Renal Insufficiency

Abstract
IN the evaluation of patients with impairment of renal function it is often important to delineate the anatomic status of the urinary tract. For this purpose retrograde pyelography is customarily employed since it is generally believed that intravenous urography will not provide adequate visualization in the presence of renal insufficiency.1 2 3 4 5 6 7 8 Some authors state that in the presence of "azotemia," the procedure is useless; others indicate a specific level of blood nitrogen concentration above which visualization cannot be expected. There are no published data, however, defining the degree of renal insufficiency incompatible with satisfactory urographic examination. Only an occasional observer has . . .