Update on interventional treatment of urinary obstruction.

During the last 20 years percutaneous nephrostomy has evolved as one of the basic procedures in the management of obstructive uropathy. This procedure is now widely available, it is relatively safe, and it offers rapid treatment of urinary obstruction regardless of underlying cause. Percutaneous nephrostomy is also the first step in a variety of antegrade ureteral procedures, including stent placement and ureteral dilation.