Pediatric ECIRS (Endoscopic Combined Intrarenal Surgery) by Dr. Prabhu Karunakaran, Hyderabad

Kidney stones in children present unique challenges due to their small anatomy and the complexity of stone location within the kidney. As a pediatric urologist practicing in Hyderabad, I have encountered various cases where traditional stone removal methods fall short, especially when dealing with complex renal calculi. One such advanced technique that has proven highly effective is Pediatric ECIRS, or Endoscopic Combined Intrarenal Surgery. This article elaborates on this complex procedure, highlighting its nuances, benefits, and my experience performing it in a one-year-old child.

Understanding Pediatric ECIRS

ECIRS is a combined approach involving both Retrograde Intrarenal Surgery (RIRS) and Percutaneous Nephrolithotomy (PCNL). This dual technique is particularly useful when kidney stones are located in challenging anatomical regions or when multiple stones are present in different calyces of the kidney. In pediatric patients, the small size of the kidney and delicate structures require careful planning and expert execution.

The term “complex renal calculi” refers to stones that are not only multiple but also located in difficult-to-access areas such as the lower pole calyx or near the infundibulum. These stones often resist removal by flexible ureteroscopy alone due to anatomical constraints.

Case Overview: One-Year-Old Child with Complex Kidney Stones

Let me take you through a recent case that underscores the complexity and success of Pediatric ECIRS. The patient was a one-year-old child with two kidney stones on the left side: a 10 mm stone in the renal pelvis and a 5 mm stone in the lower pole. Imaging studies, including a CT scan, revealed these stones clearly. Importantly, the infundibulopelvic (IP) angle was a critical factor in planning the surgery. The IP angle is the angle between the renal pelvis and the infundibulum leading to the calyx, and it significantly influences the ability to maneuver flexible scopes into the lower pole calyx.

In this child, the IP angle was less than 120 degrees, indicating a steep angle that makes it difficult to navigate flexible scopes into the lower pole calyx. When the IP angle is less than 120, it is often impossible to reach the stone with flexible ureteroscopy alone, necessitating a combined approach.

The Surgical Procedure: Step-by-Step

1. Initial Ureteric Access and Flexible Ureteroscopy

The procedure began with the placement of a guide wire after removing the previously inserted stent. A 9 French ureteric access sheath was gently advanced into the left renal system using rotatory movements. It is crucial to stop short of the pelvi-ureteric junction (PUJ) to avoid ischemic injury or trauma to this delicate area.

Once the access sheath was in place, a 7.5 French flexible ureteroscope was introduced through the sheath. Under direct vision, the stones in the renal pelvis were identified. The laser was then used to fragment or dust the stones, depending on the size and hardness.

Laser settings are vital for effective stone management:

High energy and low frequency settings are used for fragmenting stones into retrievable pieces.
Low energy and high frequency settings are used for dusting stones into fine particles that can pass spontaneously.

In this case, the pelvic stone was successfully fragmented and dusted, allowing for clearance through the urinary tract.

2. Challenges with Lower Pole Access

Despite successfully treating the pelvic stone, accessing the lower pole stone proved difficult due to the steep IP angle. While the flexible ureteroscope could be maneuvered into the lower pole calyx, the guide wire and laser fiber could not be passed effectively because of the increased rigidity when instruments are inserted.

3. Ultrasound-Guided Percutaneous Puncture

To overcome this limitation, an ultrasound-guided puncture of the lower pole calyx was performed using a 20-gauge spinal needle. This stone-guided puncture under real-time imaging ensured precise access to the stone-bearing calyx without damaging surrounding tissues.

4. Tract Dilation and Nephroscopy

Following the puncture, the tract was dilated gradually to accommodate a 16 French amplatz sheath. A 12 French nephroscope was then introduced through this sheath, allowing direct visualization and removal of the lower pole stone using grasping forceps.

5. Combined Visual Guidance and Stone Clearance

This combined approach—retrograde flexible ureteroscopy through the ureteric access sheath and antegrade nephroscopy through the amplatz sheath—allowed complete stone clearance. The visual supervision throughout the procedure minimized the risk of bleeding and injury, which is especially important in such a young patient.

Advantages of Pediatric ECIRS

ECIRS offers several distinct advantages when managing complex kidney stones in children:

Higher stone-free rates: Combining retrograde and antegrade approaches ensures that stones in all kidney regions are accessible and removable.
Reduced radiation exposure: Ultrasound guidance and direct visualization reduce reliance on fluoroscopy, benefiting pediatric patients sensitive to radiation.
Minimized bleeding and trauma: Visual supervision during puncture and dilation allows precise access with fewer attempts, reducing complications.
Better anatomical assessment: The use of flexible ureteroscopy enables detailed evaluation of the entire collecting system before and during surgery.

Technical Expertise and Challenges

Performing ECIRS in infants and toddlers requires advanced surgical skills and specialized equipment. The small size of the urinary tract in children poses challenges in instrument navigation and increases the risk of injury. Moreover, the steep infundibulopelvic angle often complicates access to lower pole stones.

In this case, the difficulty in negotiating the flexible ureteroscope and laser fiber into the lower pole calyx due to the IP angle necessitated the percutaneous approach. Such decisions must be made intraoperatively based on anatomy and stone location.

The importance of gentle, rotatory movements when inserting the ureteric access sheath cannot be overstated. Stopping short of the PUJ prevents ischemic damage, which could lead to long-term complications.

Postoperative Outcomes and Follow-Up

Following the procedure, a malecot catheter was placed as a percutaneous nephrostomy to ensure drainage and monitor for any complications. Postoperative imaging confirmed complete stone clearance.

Children undergoing ECIRS require close follow-up to monitor kidney function, detect any residual stones, and manage potential complications such as infection or bleeding. The minimally invasive nature of ECIRS generally results in quicker recovery and less postoperative pain compared to open surgery.

Summary and Conclusion

Pediatric ECIRS represents a significant advancement in the management of complex kidney stones in children. By combining retrograde flexible ureteroscopy and percutaneous nephroscopy under direct visualization, this procedure offers a comprehensive solution to challenging stone locations, especially when anatomical factors like the infundibulopelvic angle limit traditional approaches.

This case of a one-year-old child with multiple stones illustrates the precision and adaptability required in pediatric urology. The successful clearance of stones through a combined endoscopic approach highlights the importance of technical expertise, careful preoperative planning, and intraoperative decision-making.

In summary, the key takeaways for Pediatric ECIRS are:

Assess the infundibulopelvic angle and stone location thoroughly before surgery.
Use a 9 French ureteric access sheath and 7.5 French flexible ureteroscope for retrograde access.
Adjust laser settings according to whether you are fragmenting or dusting stones.
Consider ultrasound-guided percutaneous puncture when access to lower pole stones is limited.
Use combined antegrade and retrograde visualization to maximize stone clearance and minimize complications.
Ensure gentle handling of instruments to preserve delicate pediatric urinary anatomy.

For parents and caregivers, understanding the complexity of pediatric kidney stones and the advanced techniques available can provide reassurance that even the most challenging cases can be managed successfully with minimal morbidity.

If you have any questions or need further clarification on pediatric kidney stone management, feel free to reach out. Our team at Hyderabad is dedicated to advancing pediatric urology care and improving outcomes for our youngest patients.