Predictive value of 99mTc-DTPA renography studies under conditions of maximal diuresis for the functional outcome of reconstructive surgery in children with obstructive uropathy.

Renographic studies under standardised conditions of maximal diuresis provoked by infusion of hypotonic saline and frusemide were made on 51 patients with 54 dilated upper urinary tract systems in order to distinguish obstructed from non-obstructed systems. Of the 23 systems judged on clinical and radiological grounds to be obstructed only 12 were in fact obstructed following infusion of hypotonic saline and frusemide. In 10 of these systems (10 patients) an Anderson-Hynes pyeloplasty was carried out. All systems showed improved renal function after operation and the renographic pattern became non-obstructed.