A comparison of Amplatz dilators and metal dilators for tract dilatation in mini-percutaneous nephrolithotomy

Purpose Our aim was to compare the different characteristics and outcomes of the Amplatz sheaths and single-step metallic dilators which were used for mini-PCNL procedure in a single institution. Methods Retrospective medical records of 236 patients who underwent mini-PCNL were reviewed and divided into Amplatz (n = 151) and metal (n = 85) groups. Perioperative and postoperative data including operative time, fluoroscopy time, hemoglobin decrease, blood transfusion, hospital stay, stone-free rate and any postoperative complication were recorded. Results The groups were statistically similar in terms of operation time, nephrostomy stay, puncture location and hemoglobin decrease. Compared to the metal sheath group, the fluoroscopy time (3.7 vs 5.9 m, p < 0.001) and the hospital stay (53.5 vs 67 h, p = 0.007) were significantly higher in the Amplatz group. Although final stone-free rate was higher for metal group than Amplatz group, no statistical difference was established (82.1 vs 79.5%, p = 0.285). The rates of complications such as fever, blood transfusion, postoperative DJ insertion were similar in two groups with no significant difference. Conclusions Although different treatment outcomes of various institutions have been published for mini-PCNL procedure, this is the first study that compares Amplatz and metallic sheaths. This study shows that there is no difference between the two groups in terms of final stone-free rate and complication rate. Even though the indications of each dilatation technique were similar, metal sheaths are most cost-effective (6.1 vs 63 Euro per case; p < 0.001).