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Tips and tricks for the management of retained ureteral stents.

BACKGROUND AND PURPOSE
Retained ureteral stents, especially those that are encrusted and associated with a stone burden, can be a difficult management problem. We review our experience and the different options employed for treating this complication.


PATIENTS AND METHODS
From July 1998 to February 2002, 26 retained ureteral stents were managed in our department. The average patient age was 45.9 years (range 8-77 years). The average time the stent had been in place was 10.7 months (range 3-28 months). Prior to planning definitive therapy, a plain radiograph with tomographic views was reviewed.


RESULTS
A guidewire or Glidewire was often placed adjacent to the stent in order to maintain ureteral access and in some cases was able to facilitate removal of the retained stent. The patients required an average of 2.7 endourologic procedures (range 1-4) performed at one or more sessions to remove the stent and all associated stone burden. If the stone burden could not be entirely removed then stent extraction and subsequent sessions were performed until stone-free status was achieved. Cystolitholapaxy was required to treat the distal component of stent encrustation in 20 cases. Percutaneous nephrolithotomy was performed in four patients, antegrade ureteroscopy with or without intracorporeal lithotripsy in four patients, retrograde ureteroscopy with or without laser lithotripsy in five patients, and extracorporeal shockwave lithotripsy in seven patients to treat the proximal component of stent encrustation. The stent could be removed in a single anesthetic session in 23 of 26 cases (88.5%). Analysis revealed that the major component of the encrustations was a combination of calcium oxalate and phosphate.


CONCLUSION
Successful management of retained ureteral stents requires careful planning and may entail a combination of endourologic approaches. It is imperative to avoid using significant force, which can result in severe ureteral injury or breakage of the stent. If encrustations are present along the stent, we believe in treating the distal component prior to managing any proximal or ureteral components.