Application of the Matryoshka Effect in Percutaneous Nephrolithotomy for Managing Staghorn Stones

Background: Staghorn calculi remain one of the most challenging forms of nephrolithiasis due to their complex morphology and high risk of surgical complications. While standard percutaneous nephrolithotomy (PCNL) is commonly employed, it carries a greater risk of bleeding and parenchymal injury. Recent advancements have explored the potential benefits of tract miniaturization and staged tract dilation to enhance procedural safety. Objective: To assess the safety and efficacy of applying the Matryoshka effect in percutaneous nephrolithotomy for managing staghorn stones Methods: A retrospective study was conducted on 35 patients with staghorn calculi who underwent percutaneous nephrolithotomy using the Matryoshka effect. Outcomes assessed included stone-free rate, intraoperative parameters, and perioperative complications. Results: The mean age was 50 ± 10 years, with males accounting for 75% of cases. Complete staghorn stones were present in 42.9% of patients, and the mean stone surface area was 863.7 ± 465.2 mm². Twenty-eight patients underwent the creation of a new access tract, while seven patients had stones removed through an existing tract. The stone-free rate was 71.4%. The mean operative time was 60.9 ± 16.2 minutes, and the average hemoglobin drop was 1.35 g/dL. Complications occurred in six patients, most of which were minor. Conclusion: The Matryoshka tract technique is a safe and effective approach for managing large staghorn calculi. Initial access via a mini-tract not only facilitates safer dilation to a standard tract but also helps identify unfavorable cases early, avoiding unnecessary conversion to a larger tract.