Radioisotopic transit parameters in obstruction of pelviureteral junction.

Cortical and whole kidney radionuclide transit parameters were studied in 16 patients who underwent a pyeloplasty for unilateral pelviureteral junction (PUJ) obstruction. As expected, the whole kidney mean transit time was found to be very sensitive but, due to the low specificity, not very helpful in the distinction between obstructed and nonobstructed kidneys. The cortical transit reflected, in some cases, the favorable surgical outcome. In other cases, however, it could not be considered as a reliable parameter of the clinical status, since it was found to be normal preoperatively and prolonged postoperatively in patients whose parenchymal function improved significantly after surgery and who had their clinical symptoms relieved.