Endourological management of forgotten encrusted ureteral stents.

PURPOSE To present our experience and discuss the various endourological approaches for treating forgotten encrusted ureteral stents associated with stone formation. MATERIALS AND METHODS From July 2006 to December 2008, 14 patients (11 men and 3 women) with encrusted ureteral stents were analyzed. The average indwelling time of the stent was 4.9 years (range 1 to 12). Plain-film radiography was used to evaluate encrustation, stone burden, and fragmentation of the stents. Intravenous urogram and a Tc99m diethylene triamine penta acetic-acid renogram was used to assess renal function. RESULTS In seven patients, the entire stent was encrusted, in three patients the encrustation was confined to the ureteral and lower coil part of the stent, two patients had encrustation of the lower coil, and minimal encrustation was observed in two patients. Percutaneous nephrolithotomy was performed in 5 cases and retrograde ureteroscopy with intra-corporeal lithotripsy in 9 patients. Cystolithotripsy was used to manage the distal coil of the encrusted stent in eight patients. Simple cystoscopic removal of the stents with minimal encrustation was carried-out in two cases. Looposcopy and removal of the stent was performed in one patient with an ileal conduit and retained stent. Only one patient required open surgical removal of the stent. Thirteen out of 14 patients were rendered stone and stent free in one session. All except two stents were removed intact and stone analysis of encrustation and calcification revealed calcium oxalate and calcium phosphate in the majority of the cases. CONCLUSION Endourological management of forgotten encrusted stents is highly successful and often avoids the need for open surgical techniques.