Percutaneous nephrostomy for assessment of functional recovery of obstructed kidneys.

The use of percutaneous nephrostomy to evaluate the recoverability of function of the obstructed kidney is described and examined as a practical clinical method. Long-term drainage was used to assess the functional status of four kidneys and found to be of great value. The use of percutaneous nephrostomy to evaluate function has been mentioned previously but has not become established. In view of inaccuracy of other methods of assessment, we consider percutaneous nephrostomy to be the most accurate predictive test available today and suggest criteria for its use.