Percutaneous Retrieval of Upper Urinary Tract Foreign Bodies and Calculi

PURPOSE: To determine, when extracorporeal shockwave lithotripsy is contraindicated, the usefulness and safety of percutaneous management in the removal from the upper urinary tract of foreign bodies and calculi, or small remnants of these, retained affer percutaneous nephrolithotomy. MATERIALS AND METHODS: Between January 1996 and May 2001, we attempted to retrieve foreign bodies or calculi from the upper urinary tract of 20 patients, using various percutaneous techniques. There were eleven foreign bodies, namely fragmented nephrostomy catheters (n=2), migrated ureteric stents inaccessible to retrograde ureteroscopic management (n=8), and one metallic radiopaque marker which was separated from the pusher of the internal ureteral stent. Nine urinary tract calculi were present. These ranged in radiographically measured size from 4 to 8 mm in their largest diameter, and were found in the renal pelvis or calyx (n=5) and ureter (n=4). After percutaneous nephrostomy, all procedures involved the use of a 7-F to 14-F sheath, inserted under fluoroscopic guidance. Devices used for the retrieval of these objects include a stone basket retriever, loop snare, grasping forceps, and balloon catheter. RESULTS: In all cases except one, it was possible to retrieve calculi or other items from the upper urinary tract. No surgical procedure was required and no significant complications were encountered in any of the cases during or after the procedures. CONCLUSION: The percutaneous technique can be useful and safe in the management of foreign bodies or calculi present in the upper urinary tract.

Removal of Ureteral Stents by Fluoroscopic Guided Second Snare Technique: Technical Note

The snare technique has been used for the removal of ureteral stents. If, however, a stent has migrated to theupper or lower pole calyx, snaring-due to close contact between the stent and the calyceal mucosa or narrow spaceof the renal calyx-is impossible. By using the second suare technique, which involves snaring the previouslyinserted guidewire, the large renal pelvic space can be used for the removal of a migrated ureteral stent. Wedeseribe two cases and discuss the safety and efficacy of this technique.

Postoperative Ureteral Injury Treated by Percutaneous Nephrostomy and Ureteral Stent

PURPOSE: To evaluate percutaneous nephrostomy and ureteral stent placement in patients with postoperative ureteral injury. MATERIALS AND METHODS: Percutaneous nephrostomy and antegrade ureteral stent placement we reattempted in 12 patients with postoperative ureteral injuries. The previous operations which caused ureteral injuries included ureteroscopic extraction of ureteral stones(7), total abdominal hysterectomy due to uterinemyoma(2), ureteroscopic biopsy in a patient with ureteral tuberculosis(1), open ureteroplasty due to retroperitoneal fibrosis(1), and ureterocystostomy during renal transplantation(1). After percutaneousnephrostomy, a 7.0 F ureteral stent was inserted in each patient. The stent was removed under cystoscopic guidancefour to six weeks after this procedure. Urinalysis was performed to evaluate the presence of urinary tractinfection after ureteral stent placement. Ultrasonography and/or intravenous urography were performed three weeksafter stent placement, and every six months after the stent removal. RESULTS: Percutaneous nephrostomy andplacement of an antegrade ureteral stent were successfully performed in all 12 patients. In three patients, the diagnosis of ureteral injuries was made immediately and in nine was delayed for between two and nineteen days. Theureteral stents remained in position for 25-95 days (average, 51) ; no evidence of urine leakage or ureteralstricture was seen on the follow-up examinations carried out from six months to several years after removal of thestent and no case required reintervention. CONCLUSION: Percutaneous nephrostomy and antegrade ureteral stentingare easy to perform, provide for the drainage of urine, cause no significant complication and show a successful therapeutic effect, and are this effective non-operative interventional techniques for patients with postoperative ureteral injury.