Evaluation of obstructive uropathy in children. 99mTc-DTPA renography studies under conditions of maximal diuresis.

Renographic studies under standardised conditions of maximal diuresis provoked by hypotonic saline infusion and frusemide were used in 17 patients with dilatation of the upper urinary tract in order to distinguish between obstructed and non-obstructed urinary tracts. Of the six patients who were obstructed on clinical and X-ray evidence only three showed an obstructed pattern on the renographic curves after maximal diuresis. After operation these three patients showed improvement in both renographic curve and functional images of the renal parenchyma. A new method of identifying the parenchymal area is described.