Modified technique for dilatation of difficult nephrostomy tracts.

Dilatation of a percutaneous nephrostomy tract often is a difficult step, especially in patients who had previous renal surgery. Initial use of the central rod of a telescoping metal dilator set with the backloaded first dilator allows us to avoid using the fascial dilators, which are not rigid enough to dilate the tough perirenal fibrous tissue. It also permits one-stage placement of the "safety" guidewire. This technique has proved so advantageous and convenient that we now use it routinely in all cases whether they are recent or recurrent.