Uretero-Pelvic Junction Obstruction
The ureter, which is the drainage tube from the kidney to the bladder, is 10 inches (25 cm) long and has three constrictions along its course: where the pelvis of the ureter joins the ureter, where it is kinked as it crosses the pelvic brim or where it pierces the bladder wall.
Blockage of the ureter can be congenital (something one is born with) or acquired. Congenital causes include malformation of the ureteral muscle, which cannot function to help push urine down to the bladder. This is more common in children. In adults, an extra artery or vein to the lower portion of the kidney can cross over the ureter as it exits the kidney causing a slow, progressing kinking which leads to obstruction. Both of these congenital entities are known as ureteropelvic junction obstruction or UPJ. UPJ obstruction usually has symptoms of back pain, multiple kidney infections, and/or kidney stone formation.
When blockage is above the level of the bladder, unilateral dilatation of the ureter (hydroureter) and renal pyelocalyceal system (hydronephrosis) occurs. The pain resulting from UPJ obstruction is relatively steady and continuous, with little fluctuation in intensity, and often radiates to the lower abdomen, testes, or labia. Other symptoms include polyuria (excessive urination) and nocturia (frequent nighttime urination).
Confirming the diagnosis is straightforward. Either an IVU (intravenous urogram) X-ray study or a CT scan will show a sluggish, stretched-out kidney pelvis with little drainage of the IVU dye from the kidney to the ureter. Next, a renal scan will look at the kidney function and measure the transit time of the injected dye from the kidney to the bladder. The transit time of the dye is normally under 10 minutes but can be as long as hours in the blocked kidney.
Treatment Options
Endoscopic techniques, which use an instrument that is threaded through the urethra and bladder, can look into the ureter and cut the blockage. This procedure, called an endopyelotomy, can be performed as long as no crossing blood vessel is found on CT. While these are relatively quick procedures to perform, the success rates are limited to only 40-60% with a greater difficulty for future laparoscopic reconstruction of the ureter.
Another technique for cutting the obstruction involves abdominal surgery, called an open pyeloplasty. This surgery requires full anesthesia and a long hospital stay because it is requires opening the abdomen to get at the ureters.
Laparoscopic pyeloplasty is a minimally invasive approach to the standard open pyeloplasty. The surgery involves cystoscopy (looking in the bladder), stent placement (drainage tube in the ureter), and reconstruction and re-connection of the ureter through three small puncture holes. The procedure has a 95% success rate.
Surgical Treatment: Pyeloplasty
Pyeloplasty is the surgical reconstruction or revision of the renal pelvis to drain and decompress the kidney . Most commonly it is performed to treat an uretero-pelvic junction obstruction if residual renal function is adequate. This revision of the renal pelvis treats the obstruction by excising the stenotic area of the renal pelvis or uretero-pelvic junction and creating a more capacious conduit using the tissue of the remaining ureter and renal pelvis.
Pyeloplasty is traditionally performed using an open approach, which requires a large abdominal incision. Another approach, conventional laparoscopy, is less invasive, but limits the doctor's dexterity, visualization and control, compared to open surgery.
da Vinci ® Pyeloplasty
If your doctor recommends surgery for uretero-pelvic junction obstruction, you may be a candidate for a new, minimally invasive approach ― da Vinci Pyeloplasty.
da Vinci Surgery uses state-of-the-art technology to help your doctor perform a more precise operation than conventional instrumentation allows. It offers numerous potential benefits over a conventional open surgery, including:
- Significantly less pain
- Less blood loss
- Fewer transfusions
- Lower risk of infection
- Less scarring
- Shorter hospital stay
- Shorter recovery time
- Better clinical outcomes, in many cases
da Vinci Pyeloplasty incorporates the best techniques of open surgery and applies them to a robotic-assisted, minimally invasive approach.
The precision and dexterity afforded by the da Vinci Surgical System's advanced instrumentation facilitates a minimally invasive approach for treating uretero-pelvic junction obstructions. As with any surgery, these benefits cannot be guaranteed, as surgery is patient and procedure specific. If you are a candidate for a pyeloplasty talk to a urologist who performs da Vinci Surgery for Uretero-Pelvic Junction Obstruction.
To find a da Vinci urologic surgeon, use our surgeon locator .
While clinical studies support the effectiveness of the da Vinci® System when used in minimally invasive surgery, individual results may vary. Surgery with the da Vinci Surgical System may not be appropriate for every individual. Always ask your doctor about all treatment options, as well as their risks and benefits.