A Comparison of the Alken Metallic Telescopic Dilator and Amplatz Serial Dilator for Renal Access in Percutaneous Nephrolithotomy

Background: Access to the renal calyx is a challenging and crucial step for a successful percutaneous nephrolithotomy (PCNL). There are different methods of access tract dilatation, and there is no consensus on which method is the best. We conducted a comparative retrospective study on the safety and efficacy of the Alken metallic dilator and Amplatz dilator for renal access in PCNL.

Methods: We retrospectively reviewed the medical records of 80 patients who underwent PCNL between March 2023 and February 2024, and they were divided into two groups. Group A (n=42) comprised patients where Alken dilators were used, while group B (n=38) comprised patients where Amplatz dilators were used. Safety parameters, that is, perioperative bleeding, blood transfusion, access time, postoperative fever, and urosepsis, were compared between the groups. Efficacy in terms of successful renal access and stone clearance was also compared.

Results: The mean access time (mins) was longer in group B than group A (8.1 vs. 7.3, p=0.012). The intraoperative bleeding was more in group B (15.7% vs. 4.7%, p<0.001). Group B had more hemoglobin (g/dl) drop (1.3 vs. 0.7, p<0.001) and need for blood transfusion (18.4% vs. 7.14%, p<0.001) and VAS score (p<0.001) than group A. Postoperative urosepsis was more common in group B. Efficacy in terms of successful renal access and stone clearance was comparable.

Conclusion: The Alken dilator group has a lower rate of blood transfusion and postoperative VAS score. The Amplatz dilator group had more incidences of postoperative urosepsis. The efficacy in both groups was comparable.