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Precision Stone Surgery: Current Status of Miniaturized Percutaneous Nephrolithotomy


Purpose of Review

Innovations in lasers and surgical technology have led to a renewed interest in the miniaturization of percutaneous nephrolithotomy (PCNL). We review the different approaches and evidence on the efficacy of mini-PCNL.

Recent Findings

Mini-PCNL encompasses a range of techniques using tract sizes from 4.8 to 22 F to treat renal stones. The most common device uses irrigation to passively extract stones out of the sheath. Super-mini-PCNL incorporates active suction. Ultra- and micro-techniques reduce the tract to smaller diameters. Laser fragmentation is the main lithotripsy modality. Studies demonstrate an association with reduced complications, hospital stay, and increased tubeless rate. Drawbacks include longer operative times while stone-free rates for larger stones may be sub-optimal.


Mini-PCNL has advantages of less trauma and the avoidance of nephrostomy tubes. Ambulatory surgery is feasible in select patients. Advances in laser lithotripsy and active suction have the potential to improve stone clearance and treat larger stones.

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Fig. 1



Percutaneous nephrolithotomy


American Urological Association


European Association of Urology


Miniaturized PCNL


Super mini-PCNL


Ultra mini-PCNL





NT :

Nephrostomy tube


Stone-free rate


Length of stay




Kidney, ureter, and bladder X-ray


Randomized controlled trial


Residual fragment


Computed tomography


Lower pole


Hounsfield unit


Endoscopic combined intrarenal surgery


Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

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Correspondence to John M. DiBianco.

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Dr. Ghani reports personal fees from Lumenis, grants and personal fees from Boston Scientific, personal fees from Olympus, personal fees from Coloplast, grants from Blue Cross Blue Shield of Michigan, outside the submitted work.

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DiBianco, J.M., Ghani, K.R. Precision Stone Surgery: Current Status of Miniaturized Percutaneous Nephrolithotomy. Curr Urol Rep 22, 24 (2021).

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  • Nephrolithiasis
  • PCNL
  • Mini-PCNL
  • Technology