Ureteral reimplanta­tion: reattaching the ureter to the bladder

Goal of the operation

The ureter carries urine from the kidney to the bladder. Normally it passes through the bladder wall in a slanted tunnel, and this tunnel works like a valve: when the bladder fills, it does not let urine flow back to the kidney.

Ureteral reimplantation (ureteroneocystostomy) means reattaching the ureter to the bladder through a new tunnel of the right length. The goal is to stop urine from flowing back to the kidney, or to remove a narrow segment so that urine flows freely.

When is it needed?

• Vesicoureteral reflux (VUR): if febrile infections keep coming back despite prophylaxis, new kidney scars form, high-grade reflux does not resolve as the child grows, or endoscopic injection has not worked.
• Obstructive megaureter: if kidney function declines during follow-up, the dilation increases or infections keep coming back.
• Duplex kidney and ectopic ureter, some cases of ureterocele.

Most reflux resolves as the child grows or is treated with endoscopic injection, so not every child needs reimplantation.

How is the operation done?

The operation is done under general anesthesia and usually takes 2–3 hours. There are two main approaches:

• From inside the bladder (intravesical): a 4–6 cm incision low on the abdomen, along the bikini line. In the most widely used Cohen method, the ureter is moved into a new tunnel under the bladder wall toward the opposite side. Both sides can be corrected in the same operation.
• From outside the bladder (extravesical, Lich-Gregoir): the bladder is not opened; the ureter is placed in a channel created in the bladder wall. It can be done open or with the robot-assisted laparoscopic method through small incisions.

In megaureter, the narrow segment is removed, the very dilated ureter is made narrower, and then it is stitched to the bladder. In these cases, a temporary JJ stent is placed to help the stitched area heal, and it is removed 4–6 weeks later under a short anesthetic.

In babies

In children under one year of age, the bladder is small, so reimplantation, especially for megaureter, is postponed when possible. Until then, measures are taken to protect against infection. If needed, temporary solutions are chosen: endoscopic balloon dilation, a stent, or bringing the ureter out to the skin temporarily.

In the hospital and at home

• The hospital stay is usually 2–4 days, sometimes shorter with the robotic method.
• The urinary catheter usually stays in for 1–3 days.
• In the first days, bladder spasms and a little blood in the urine are normal. A medicine that relaxes the bladder is given for the spasms.
• At home, no heavy physical activity, cycling or swimming pools for 2–3 weeks.
• Drink plenty of fluids, use the toilet regularly and prevent constipation.

Possible complications

Complications are rare. The most common are:

• Persistent reflux: in 2–5% of cases.
• New reflux on the other side: in about 10% of children after one-sided surgery. It is usually mild and resolves on its own.
• Temporary dilation or narrowing: in the first weeks, swelling can make the ureter look dilated on ultrasound; this usually passes. Permanent narrowing is rare.
• Urinary retention: sometimes temporary after surgery done from outside the bladder on both sides.

Follow-up

• ultrasound 4–8 weeks after surgery,
• then ultrasound at 6–12 months,
• a VCUG is not needed for every child; it is done if a febrile infection occurs,
• in megaureter, MAG3/DTPA if needed.

Treatment of constipation and a regular toilet routine continue after surgery as well, because they lower the risk of infection.