Nuclear imaging supplementary to urography in obstructive uropathy.

In 50 patients with obstructive uropathy, nuclear imaging supplementary to excretory urography did not improve the detection of obstruction or the determination of the site or etiology of the lesion. However, rapid sequential radionuclide images showed decreased renal perfusion in 64%, more frequently than did an obstructive nephrogram (40%); this finding appeared to occur with more severe degrees of obstruction. Functional impairment of the obstructed kidney was demonstrated more often with 131I Hippuran (o-iodohippurate sodium) (91%) than with 99mTc glucoheptonate (68%) or excretory urography (66%). Neither nuclear nor urographic studies could predict the degree of functional recovery of the kidney until the increased intrapelvic pressures was relieved.