Lateral drainage metal ureteric stent for the treatment of 'Y-shaped' branch obstructive uropathy.

Abstract

To evaluate the efficacy and safety of the HuaXi technique of a lateral drainage Memokath™ metal ureteric stent (MMUS; Pnn Medical A/S, Kvistgaard, Denmark) for 'Y-shaped' branch obstructive incomplete duplicated collecting systems (IDCS) and intra-pelvic branch atresia (IPBA). Between November 2023 and December 2024, a prospective study and follow-up observations were conducted on 20 patients who underwent MMUS placement for IDCS and IPBA at our centre. Surgical success was defined as the initially implanted stents requiring no replacement during follow-up and maintaining unobstructed drainage, or following planned stent replacement or removal performed, there was no worsening of renal hydronephrosis in the patient. Based on the lateral drainage characteristics of the MMUS, it was selected for treating four distinct types of 'Y-shaped' branch obstructive uropathy. During the 1-year follow-up period, the overall success rate of MMUS placement reached 85.0%. At 1 month postoperatively, hydronephrosis volume significantly decreased (mean [standard deviation (SD)] 64.2 [63.8] vs 35.6 [39.7] cm³, P = 0.028), with serum creatinine levels (mean [SD] 97.2 [57.9] vs 90.6 [54.8] μmol/L, P = 0.046) and urea nitrogen levels (mean [SD] 5.2 [1.0] vs 4.9 [0.8] mmol/L, P = 0.036) were significantly reduced, while glomerular filtration rate remained stable (mean [SD] 81.1 [23.1] vs 80.3 [22.8] mL/min/1.73 m², P = 0.083). The 1-year postoperative outcomes were similar to those at 1 month postoperatively. During follow-up, no patients experienced uncontrollable postoperative complications. Stent-related complications primarily involved haematuria (15.0%). All complications resolved spontaneously after symptomatic management. Short-term follow-up indicates that lateral drainage MMUS offers a safe and effective treatment for 'Y-shaped' branch obstructive uropathy. For patients unsuitable or unwilling to undergo urinary tract reconstruction surgery, endoscopic MMUS placement provides an optimal and viable alternative.