A ureteral stricture is a narrowing of the ureter that makes it difficult or impossible for urine to pass from the kidney to the bladder. There are many causes, such as impacted ureteral stones, ureteroscopy, surgical injury, trauma, radiation, and cancer. Patients with ureteral stricture often develop pain in the back or flank related to urinary obstruction of the kidney, but sometimes people are asymptomatic from this. Ureteral obstruction may result in renal insufficiency, loss of that particular kidney, and / or urinary infections. These strictures are often temporized by placement of a ureteral stent, which may be done cystoscopically (transurethrally), or by placement of a percutaneous nephrostomy tube (a tube to drain the kidney directly through the back). There are several ways to repair ureteral strictures, when warranted. These methods include:
- Ureteral balloon dilation
- Segmental ureterectomy
- Ureteral reimplantation into the bladder
- Interposition of bowel
- Kidney auto-transplantation
Ureteral balloon dilation:
This is a cystoscopic method, performed transurethrally. A catheter is placed across the stricture and the stricture is dilated. A ureteral stent is then left indwelling for several weeks. This is the least invasive method for approaching this problem, but the success rate with this is very poor.
Segmental ureterectomy involves splicing out the small diseased aspect of the ureter and re-connecting the good portions of ureter to each-other. This technique is applied to discretely small strictures in the mid to proximal ureter (closer to the kidney than to the bladder). The main hangup with this procedure is that the blood supply to the ureter in this location is tenuous, and these reconstructions have a significant repeat stricture rate. This surgery may be done openly or robotically.
Most ureteral strictures occur within close proximity to the bladder, and reconstruction entails bypassing the stricture by disconnecting the ureter just above the stricture and reimplanting the distal open aspect of ureter into another spot on the bladder. Often this requires pulling the bladder to the side of repair in order to take tension off of the reimplantation site. This is done by sewing the bladder to a muscle in the back, called a “psoas hitch”. (On rare occasion, the tension may not be relieved by this maneuver alone, and a “Boari” bladder flap is raised to bridge the gap). A urethral catheter is kept indwelling for about 10 days, and a ureteral stent is kept indwelling for several weeks. A cystogram is performed to verify that there is no bladder leak prior to removal of the urethral catheter. This surgery may be done openly or robotically, and the success rates with these methods are excellent. The robotic approach carries with it the usual benefits of laparoscopic surgery over open surgery:
- Less blood loss
- Less pain
- Shorter hospital stay
- Smaller scars
- Fewer wound infections and other complications
- Earlier return to activities of daily living, including driving
Ureteral strictures that are high on the ureter, close to the kidney, are not amenable to repair by direct reimplantation of the ureter into the bladder because it won’t reach that far. In select circumstances, a segment of bowel may be spliced from the gastrointestinal tract and used as a conduit for the passage of urine from the normal ureter above to the bladder below. This operation may result in electrolyte disturbances and renal insufficiency, and places the gastrointestinal tract at risk (for obstruction or leak). This surgery is rarely done.
For patients with high ureteral strictures, and particularly if it is the only functioning kidney, removal of the kidney and reimplanting the kidney closer to the bladder is an option to consider in order to preserve the kidney and avoid need for dialysis. For patients with good contralateral kidney function, removal of the offending kidney unit is often the best choice. Kidney auto-transplantation surgery is best performed by a transplant kidney specialist.