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Antegrade double J ureteral stenting for ureteric strictures: use of silicone stents.

In 16 patients with ureteric strictures, silicone double J ureteral stents were inserted antegradely following percutaneous nephrostomy. In 9 patients prior attempt at retrograde placement of a stent had failed. Balloon dilatation of the stricture using angiographic catheters was also performed in 5 patients. The ureteric strictures were most commonly caused by malignant infiltration, post operative fibrosis, infection and ureteric calculi. Most previous reports have described the use of polyethylene and polyurethrane stents. Technical problems with the use of silicone stents are discussed. Although silicone stents are better tolerated by patients and associated with low complication rates, in 5 of 18 stents inserted (28%) the procedure failed. Suboptimal positioning of the stent due to poor radio-opacity and premature occlusion were the causes. With the availability of co-polymer stents, it is likely that these will replace silicone stents as the stent material of choice for antegrade insertion.