What Is PCNL?
Percutaneous nephrolithotomy (PCNL) is a minimally invasive surgical procedure to remove large or complex kidney stones. "Percutaneous" means through the skin — the surgeon creates a small puncture (about 1 cm) in the patient's back, passes a thin telescope into the kidney, and removes or fragments the stone directly. It is the most effective treatment for large stones and avoids the need for open surgery.
When Is PCNL Recommended?
- Kidney stones larger than 20 mm in diameter
- Staghorn calculi — branching stones that fill multiple parts of the kidney
- Lower-pole kidney stones where ESWL has a lower success rate
- Stones that failed prior ESWL or ureteroscopy treatment
- Stones in abnormally positioned kidneys (horseshoe kidney, transplant kidney)
- Stones combined with a narrowing at the kidney outlet (UPJO)
How the Procedure Works
PCNL is performed under general anaesthesia and typically takes 1–2 hours:
- Positioning: The patient lies face-down (prone). Some surgeons use a modified supine position — ask your surgeon which they prefer and why.
- Ureteric stent placement: A thin tube is passed through the urethra into the ureter to inject contrast dye and help identify the kidney collecting system.
- Access (puncture): Under X-ray and/or ultrasound guidance, a needle is placed through the back skin directly into the kidney. A guidewire is then threaded through the needle.
- Tract dilation: The skin puncture is progressively dilated to about 1 cm to allow the working sheath (nephroscope) to enter.
- Stone removal: A nephroscope is passed through the sheath. The stone is either directly grasped and removed, or fragmented with an ultrasonic / laser probe and the pieces washed or suctioned out.
- Nephrostomy tube: A small drainage tube is left in the kidney at the end of the procedure. It is usually removed after 24–48 hours once the kidney is draining well.
Mini-PCNL: A Smaller Alternative
Mini-PCNL uses a narrower working sheath (less than 5 mm vs the standard 10 mm), resulting in a smaller skin puncture, less blood loss, less post-operative pain, and faster recovery. It is well suited to stones of 15–30 mm in cooperative patients with normal anatomy. The stone-free rates are comparable to standard PCNL for appropriate cases.
Recovery and Discharge
- Hospital stay: Typically 2–3 days for standard PCNL; 1–2 days for mini-PCNL.
- Nephrostomy tube: Removed before discharge once urine drains clearly.
- Return to light activity: 5–7 days after discharge.
- Return to full activity / work: 2–3 weeks for desk work; 4–6 weeks for heavy physical labour.
- Follow-up imaging: An ultrasound or CT at 4–6 weeks confirms stone-free status.
- Pain: Usually manageable with oral paracetamol and an anti-inflammatory. Significant pain after discharge should prompt a call to the surgeon.
PCNL is safe but all surgery carries risks. Discuss these with your surgeon: significant bleeding requiring transfusion or embolisation (2–3%), infection / sepsis (managed with antibiotics; preventable with good pre-operative urine sterilisation), injury to surrounding structures (rare), and residual stone fragments requiring a second procedure. Choosing an experienced surgeon significantly reduces these risks.
Speak with Dr. Azhar Anwar about your stone burden and whether standard or mini-PCNL is appropriate for you.