Problems with double-J stents and nephrostomy tubes.

Double-J stents and nephrostomy tubes are used both to temporize prior to definitive treatment and for long-term relief of ureteral obstruction. Nephrostomy tubes that are correctly placed guarantee relief of obstruction and facilitate intrarenal manipulations but have a number of disadvantages, not least of which is the need for an external collecting bag. Double-J stents obviate the external bag but do not ensure relief of obstruction and have adverse functional and histopathologic effects on the ureter. Despite improvements in materials, no stent is totally resistant to encrustation, and frequent changes are required.