Definition and Overview
The release of ureter is a procedure used to treat ureteral obstructions and strictures. By releasing and draining the ureters in such cases, the procedure allows the kidneys to function normally.
The ureter is a small thin tube that connects the kidney to the bladder. If it is blocked or obstructed, it has to be released so it can resume transporting urine to the bladder and prevent further complications.
Who Should Undergo and Expected Results
The procedure to release the ureter is necessary for patients who suffer from ureteral obstruction, which may be caused by:
Congenital/developmental problem - The ureteropelvic junction (UPJ), which is located in the upper abdomen, connects the kidney and the ureter to each other. Certain congenital or developmental abnormalities can affect how the kidney pushes urine towards the UPJ and into the ureter (a process called peristalsis).
Ureteral strictures (scarring) - The ureter can sometimes develop scarring due to previous surgery, which can cause kidney blockage.
Retroperitoneal fibrosis - Refers to the inflammation of abdominal organs around the ureter.
Urethritis - Refers to the inflammation of the urethra.
Kidney stones - A stone in the kidney may cause kidney obstruction and produce the same complications as urethral obstruction.
Cancer - Some cancerous tumours in the abdomen may push through or compress the ureter. These include cervical, ovarian, uterine, colon, prostate, and bladder cancers.
Ureteral stricture, which is one of the most common reasons why the release of ureter is performed, is a common complication of some surgical procedures that are performed on structures that are close to the ureter. The most commonly associated surgeries include:
Kidney stone removal surgery
Abdominal vascular surgery, or surgery involving the arteries in the abdomen
Obstetric or gynaecologic surgery, such as the removal of the ovaries or uterus - The link between gynaecologic surgery and urethral strictures is due to the close proximity of the ureters to the arteries of the uterus and ovaries. If the ureter injury is only detected after the operation is complete, it may not be treated immediately due to the inflammation that normally occurs after a surgical procedure. In such cases, doctors have to wait between 6 and 12 weeks before the ureter can be surgically released. To facilitate proper urination, a nephrostomy tube, which bypasses the stricture, is used to drain out the urine from the kidney.
After the ureter has been released, patients can expect relief from abdominal pain as the kidney, ureter, and bladder start working properly again.
How is the Procedure Performed?
The manner in which the procedure is performed differs depending on the cause of the problem and the location of the blockage or stricture.
If the problem is caused by blockage or the compression of the ureter, the ureter is simply drained using a ureteral stent or nephrostomy tube.
Ureteral stent - Also called a ureteral double-J stent, this is an internal tube that connects the kidney to the bladder to take over the function of the ureter. If the stent is used for kidney stones, it is also called a kidney stone stent. The kidney stent bypasses the part where the stone is located to allow urine to pass into the bladder.
Nephrostomy tube - An external tube that drains the contents of the kidney into a bag.
The ureteral or kidney stent and nephrostomy tube can be eventually removed, such as when the cause of the obstruction has been treated. An example is when a cancerous tumour has been surgically removed or shrunk by other treatments.
In some cases, the ureter has to be repaired or reconstructed after it was released. This is common among patients who suffer from urethral strictures or scarring that has caused permanent damage to some parts of the ureter.
If the ureter is damaged or scarred due to a previous abdominal surgery, the type of procedure used to release it depends on the location of the damage or scarring. If it is located in the lower part of the ureter and is closer to the bladder, the scarred part of the ureter is simply removed and the ureter is reconnected to the bladder. This procedure is called neo-cystotomy.
If the urethral stricture is too long, the ureter may need to be reconstructed once the scarred part is removed. Doctors can use either a flap taken from the bladder (Boari flap) or small bowel (ileal ureter) as a substitute.
Possible Risks and Complications
The release of the ureter is a generally safe procedure. However, patients still face a low risk of certain complications. These include:
Dislocation of the ureteral stent
Encrustation leading to blockage (also known as encrusted stents) – Factors that increase a person’s risk of encrusted stents include pregnancy, chronic renal failure, chemotherapy, and congenital abnormalities
Increased urination urgency and frequency
Pain in the kidneys during urination
Some of these complications are temporary and may disappear when the stent is removed. More recently, surgeons have begun using stents with heparin coatings. These have been proven to help reduce the risk of infection and encrustation.
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“Ureteral obstructions and strictures.” University of Utah. https://healthcare.utah.edu/urology/conditions/ureteral/
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