Narrow ureter

The ureter ensures the outflow of urine from the two kidneys into the bladder. From there, the urine flows out through the urethra. There are two ureters, one per kidney.

Since the ureter is naturally a very slender organ, even small changes can cause a narrowing. If the urine can no longer flow away from the kidney, this becomes a problem. There are a number of possible causes, such as congenital causes, infections, ureteral tumours, and masses in the abdomen. Scarred narrowing can also develop after urinary stones, radiotherapy, or surgery.

If the ureter is constricted, urinary retention occurs. If the urinary retention is acute, the patient feels a strong, colicky pain in the side (flank). Slow onset, chronic urinary retention, on the other hand, can go completely unnoticed. If left untreated, kidney failure, infections, and even life-threatening blood poisoning can occur.

If the ureteral stricture causes urinary retention, this is usually first treated by inserting a thin ureteral catheter known as a double-J stent. This only serves as an acute therapy because it does not eliminate the cause.

In the course of the procedure, a ureterorenoscopy (URS) must usually be performed under general anaesthesia to better asses the narrowing. Access is gained with a very thin and long instrument. This is inserted into the bladder through the urethra. Once inside, either the left or right ureteral orifice is chosen and then the instrument is pushed through the ureter into the constriction or the kidney. In this way, access is gained in a natural way. For certain strictures, a ureteral stent is inserted again as a part of the procedure.

Once urinary stones and tumours have been ruled out as a cause, various interventions can be performed depending on the location of the stricture.

Narrowing of the ureter at the transition area to the kidney is quite common and is known as a ureteropelvic junction obstruction. In this case, a procedure called renal pyeloplasty is used.

For strictures just in front of the bladder, the narrowing can be removed and the ureteral end reimplanted into the bladder.

Strictures in the middle third of the ureter, where the ends of the ureter cannot be sutured either to the renal pelvis or the bladder, are much less common. Direct connection of the ureteral ends carries the risk of renewed scarring of the stricture. In the case of long-stretch strictures, it is not possible to suture the ends without tension, which is why a short piece of intestine may have to be interposed (ileal ureter interpositions).

Depending on the underlying disease, age, and general condition of the patient, it can sometimes be better to treat the narrowing permanently with a double-J stent instead of a major surgical procedure. However, this splint must be changed regularly.

The inpatient admission for the robot-assisted da Vinci ureteral reimplantation takes place the day before the surgical procedure. The operation takes place under general anaesthesia. The minimally invasive instruments of the robot are inserted into the abdominal cavity using the keyhole technique. Using three-dimensional vision, the surgeon can see the ureter with the stenosis as well as the bladder and detaches them from the surrounding tissue. The stenosis is removed, and the healthy end is sewn into a new opening in the bladder. During this demanding procedure, the robot-assisted surgical technique provides the best support. Postoperative care takes place in the recovery room before transfer to the normal ward. The entire inpatient stay lasts about 7 days. The inserted ureteral stent, which serves to protect the suture site, must be removed during the course of the procedure by means of a short cystoscopy under local anaesthesia.

The most important thing in the procedure is to sew the suture in such a way that it is free of tension, as this is the only way to ensure good healing. If the healthy end of the ureter is too far away from the bladder, another solution needs to be found. In this case, the bladder is pulled upwards and attached to a muscle (psoas hitch technique). If you need to gain even more distance, a flap from the bladder is formed into a tunnel and extended upwards (Boari flap).

Due to the tenfold magnification, the anatomical structures can be visualised much better than with conventional laparoscopy. Compared to the conventional (incision) surgical technique, the result is a better outcome, less blood loss, less pain, and a shorter inpatient stay.

No.

Besides the general risks of any surgical procedure, such as bleeding or fever, there are specific risks. During the procedure, the ureter is implanted in such a way that when the bladder is full, a backflow of urine to the kidney is prevented. However, this valve mechanism can fail and lead to kidney damage over time. A narrowing can recur over the course of time and cause urinary retention again. All possible risks of the surgical intervention are discussed prior to the procedure in a detailed explanatory discussion.

In general, professional activities corresponding to an office job are possible again 3-4 weeks after the procedure. Sport and physical activities can be resumed after 3 months.

The ureteral reimplantation is performed under general anaesthesia. Due to the small incisions, hardly any pain is expected after the procedure.