Transrenal antegrade ureteral occlusion assisting percutaneous nephrolithotomy: a preliminary single-center...

To preliminarily evaluate the effectiveness and safety of transrenal antegrade ureteral occlusion as an adjunct to mini-percutaneous nephrolithotomy (mPCNL), with particular attention to stone fragment migration and perioperative outcomes.

We retrospectively reviewed patients who underwent mPCNL for renal calculi between December 2021 and December 2023 at a single tertiary center. According to intraoperative use of an antegrade ureteral occluder, patients were assigned to an occlusion-assisted mPCNL group (OA-mPCNL) or a standard mPCNL group. Group allocation was based on surgeon preference rather than predefined criteria. Baseline characteristics were compared to assess comparability. Perioperative outcomes, including operative time, blood loss, renal pelvic pressure (RPP), postoperative stone migration, stone-free rate, secondary procedures, and complications graded by the Clavien-Dindo system, were analyzed.

Eighty-four patients were included (42 per group). Baseline demographics and stone characteristics were comparable between groups. The incidence of postoperative stone migration was significantly lower in the OA-mPCNL group (2.4% vs. 16.7%, P = 0.029). There were no significant differences in operative time, hemoglobin decline, RPP, length of hospital stay, first-stage stone-free rate, or overall complication rate (P > 0.05). Although the requirement for secondary RIRS/URL was lower in the OA-mPCNL group (2.4% vs. 14.3%, P = 0.048), the overall auxiliary procedure rate did not differ significantly between groups.

Antegrade ureteral occlusion during mPCNL was associated with a lower incidence of stone fragment migration without compromising perioperative safety. However, given the retrospective design and potential selection bias, these findings should be interpreted as preliminary and hypothesis-generating rather than definitive evidence of superiority.