Upper ureteral calculi: extraction via percutaneous nephrostomy.

Symptomatic calculi in the upper ureter are usually removed using surgical and endoscopic techniques. Extraction via percutaneous nephrostomy was successful in 35 of 37 patients using sequentially the techniques of retrograde catheter push, basket sheath exchange, and steerable loop-snare. In 12 patients, the calculus was dislodged into the renal pelvis by the retrograde ureteral catheter; extraction was then easily done. Stone basket retrieval was used for an additional 17 patients. A steerable loop-snare was necessary in six other patients when basket retrieval failed.