What Is Ureteropelvic Junction Stenosis In Children?
The kidney has 10-12 small pools (calyx) and one large pool (pelvis) where these pools open. This is the case where the large pool is narrowed at the junction of the urinary tract leading to the bladder, and urine is difficult to push into the bladder.
What are the Causes of UJS in children?
Congenital kidney outflow stenosis occurs due to a narrow vascular pressure in the internal structure of the canal that we call ureter, or vascular pressure from outside to the ureter (Figure 1-2). In addition, this stenosis may be caused by the difference of the location of the ureter in the kidney.


What Findings Provide?
In fact, an enlargement of the kidney can be seen by ultrasonography during the controls in the fetal period. After birth, urinary tract infection, intermittent pain and / or infants with very swollen kidneys may experience swelling on the side of the abdomen or may be felt on examination. In addition, blood can be seen in the urine of some patients. Another important issue to note is that there is a stenosis (15%) or a different anomaly (urine leakage from the bladder to the kidney) in the opposite kidney.
Is there a method for definitive diagnosis?
Diagnosis of kidney stenosis of these children is made during pregnancy in mothers who go to regular pregnancy follow-up. In each control, the diameter of the kidney main pool is measured and the degree of the kidney is monitored. It is usually expected until birth. After birth, ultrasonography (figure 3) is performed in the first stage. If an enlargement is detected in the kidney, the diameter of the pelvis is measured and followed up. Sometimes the cause of swelling in the kidney is urine escape from the bladder to the kidney. If such a condition (vesicoureteral reflux) is suspected, the child should be given voiding cystography at 1 month after birth. The kidney pelvis is followed if its anterior-posterior diameter is below 10 mm. If it is over 20 mm, surgery decision is taken. Tighter follow-up is required between 15-20 mm. Scintigraphy is performed to reveal kidney functions and degree of kidney discharge. With ultrasonography and scintigraphy, it is investigated not only the severity of stenosis, but also the condition of the kidney, whether there is any other discomfort in the bladder.


The narrow section is removed and replanted into the kidney pool.

Should I Surely Have Surgery or Not?
Most of the hydronephrosis (enlargement of the kidney collector system) detected in the fetal controls if it is benign and does not require surgical intervention. Most of them return to normal with follow-up. However, surgery is considered if hydronephrosis increases in controls, kidney function decreases, pain, recurrent urinary tract infections or stone formation.
What are the Treatment Options?
The main treatment is surgery. The narrow section is removed and any stenosis vessel is corrected. This surgery is performed robotically, laparoscopically and openly. We perform this operation in less than 1 hour with a very small incision. The success rate of this surgery is over 90%. We prefer open surgery because we use minimally invasive technique (painless, short hospitalization, discharge on the same day). In this technique, we make a very small incision (4 cm). We enter without breaking the muscles. We use fine sewing materials. The operation time is a maximum of one hour. However, in laparoscopy, the duration of surgery can increase to three or four hours. At least three 1 cm holes are drilled. Thicker sewing materials are used.
What is Post-Surgery Follow-Up and Stent Placement?
In such surgeries, it is almost necessary to put an internal or external stent in order to heal the suture line comfortably. Internal stenting then requires a second operation with general anesthesia. Therefore, our preference is the technique of external stent placement in children under 18 years old. The disadvantage of this technique is that the patient is discharged home with a urine bag and this stent (nephrostomy stent) is withdrawn on the seventh-tenth day after surgery.
How Do We Understand That The Operation Is Successful?
This is understood in two ways. Firstly, the complaints present in the patient disappear. For example, nausea, vomiting, pain, developmental disorder, loss of weight loss, anorexia improve. The second is radiological improvement. In ultrsonography, kidney pelvis diameter decreases. If the swelling in the kidneys is stretched, DTPA renal scintigraphy shows that the kidney, which has not been emptied before or wasted empty, is now more comfortable and in a shorter time.