Robot-Assisted Surgery for Ureteropelvic junction (UPJ) obstruction

UPJ obstruction is a condition that disrupts the flow of urine from the kidney due to a narrowing of the passage from the renal pelvis to the upper ureter. It can be caused by either an internal (intrinsic) or external (extrinsic) constriction, such as from a crossing kidney blood vessel.

The delayed urine flow leads to chronic kidney obstruction and anatomical changes within the kidney, including the widening of the renal pelvis and calyces and a narrowing of kidney tissue. If left untreated, this can lead to a decline in kidney function, potentially resulting in a non-functional kidney. The condition can occur at any age and is often discovered incidentally. Some patients may experience flank pain, especially after excessive fluid intake. Other associated symptoms may include kidney stones and urinary tract infections.

Diagnosis is achieved through ultrasound, contrast-enhanced X-rays, and imaging techniques like CT and MRI. For the definitive treatment decision, a functional isotope scan of the kidneys, known as renal scintigraphy or diuresis renography (DNG), is considered a gold standard. If this examination reveals a fixed obstruction (mechanical narrowing) of the ureter, surgical intervention is indicated. During the operation, the ureteral constriction is removed, restoring unobstructed urine flow from the kidney. This is done to prevent further damage, particularly a worsening of kidney function. The current most common surgical technique is known as Anderson-Hynes pyeloplasty. Originally developed as an open surgery, the procedure has been successfully performed using traditional laparoscopic techniques. However, limitations arise from instrument mobility, particularly during sewing and knotting.

These drawbacks of conventional minimally invasive surgery (laparoscopy) can now be overcome with robotic technology. Significantly improved visualization of anatomy and substantially enhanced instrument mobility allow for precise treatment of fine anatomical structures and delicate suturing. The advantages of robotic pyeloplasty include:

• Minimal invasiveness, minimal blood loss
• Good functional outcomes
• Substantially reduced postoperative pain
• Fast wound healing, good cosmetic results
• Shorter hospital stay

As part of the surgery preparation, you’ll need clearance from your general practitioner or internist. Admission occurs on the day before the operation. You will be thoroughly informed about the procedure’s steps and potential complications. The procedure is always performed under general anesthesia.

The operation is conducted using a minimally invasive technique. Several small incisions (5mm to 12mm) are made in the abdominal wall to introduce robotic instruments and suture material. The abdominal cavity is filled with gas to create sufficient working space.

The latest-generation DaVinci surgical system provides the surgeon with a 3D image of the surgical area at 10x magnification. This enables precise manipulation of the finest anatomical structures and allows for suturing and cutting techniques in hard-to-reach areas, nearly impossible with other surgical methods.

The renal pelvis and upper ureter are first freed from surrounding structures. The narrow section is precisely defined and completely removed. Subsequently, the ureter is sutured to the renal pelvis. The suture material used is self-absorbing. To aid healing at the junction, an inner ureteral stent (a thin plastic tube between the kidney and bladder) and a bladder catheter are inserted intraoperatively. This facilitates a low-pressure urine drainage in the initial days after surgery. The operation typically lasts between one to two hours.

After the operation, all patients are initially placed in the recovery unit, where vital signs are closely monitored until transfer to the general ward is possible. On the first and second postoperative days, patients are mobilized, and the bleeding drainage is removed. On the fifth postoperative day, the bladder catheter is removed. Skin staples can be removed after the seventh postoperative day. The hospital stay, from admission to discharge, typically lasts about a week. The ureteral stent is removed in the office in 6 to 8 weeks.