Yes, renal stones can be accessed and removed through a percutaneous nephrostomy tract.
A percutaneous nephrostomy tract serves as a direct conduit to the renal collecting system, allowing access to kidney stones for extraction or fragmentation during percutaneous nephrolithotomy (PCNL). This is the standard surgical approach for large renal stones (>15 mm) and remains a cornerstone of modern stone management 1.
How the Access Works
The percutaneous nephrostomy tract is created through the following process:
- Initial puncture: A needle is inserted percutaneously into the renal collecting system under fluoroscopic or ultrasound guidance 1
- Tract dilation: The tract is dilated to accommodate instruments, typically 24-30 F for standard PCNL or <18 F for mini-PCNL 1
- Stone access: Once established, the tract provides direct endoscopic access to visualize, fragment, and extract stones from the kidney and even proximal ureter 2, 3
Clinical Applications
The nephrostomy tract enables:
- Direct stone extraction: Small mobile stones can be grasped with baskets and removed through the tract 2
- Stone fragmentation: Larger stones can be broken using ultrasonic, pneumatic, or laser lithotripsy before removal 1
- Access to difficult locations: The tract can reach stones throughout the renal collecting system when positioned correctly 4
- Ureteral stone management: Percutaneous antegrade ureteroscopy through the nephrostomy tract is an option for large (>15 mm), impacted proximal ureteral stones, especially in dilated systems or when retrograde access fails 1
Success Rates and Outcomes
Historical data demonstrates that percutaneous stone extraction through nephrostomy tracts achieves:
- 88-95% success rates for complete stone removal 3, 4
- Improved efficiency with experience: Success rates increased from 76% to 91% as operators gained proficiency 3
- Minimal morbidity: Modern PCNL has low complication rates when performed by experienced surgeons 1
Important Caveats
Proper tract positioning is critical - the nephrostomy must provide straight-line access to all stone locations while avoiding significant trauma to renal parenchyma and perirenal structures 4. This differs from simple drainage procedures and requires specific technical expertise.
The choice between standard PCNL (>22 F) and mini-PCNL (12-22 F) depends on stone burden, with mini-PCNL reducing blood loss and hospital stay while maintaining similar stone-free rates 1.
Post-procedure drainage decisions (nephrostomy tube, stent, or tubeless) should be based on surgeon preference and case-specific factors including residual stones, bleeding, or infection risk 5, 1.