METHODS: We retrospectively reviewed consecutive children undergoing minimally invasive pyeloplasty for primary ureteropelvic junction obstruction from 2016 to 2017, using the operated renal unit as the unit of analysis. Costs included standardized institutional surgical fees, instrumentation, and reoperation, expressed in United States dollars (USD). Sensitivity analyses examined capital amortization across hospital-wide robotic volume, conversion to 2025 constant USD, and acquisition-price reductions of 10%, 20%, and 30%. Effectiveness endpoints comprised operative success (no reoperation), anteroposterior renal pelvic diameter (APD) response (reduction ≥40%), Society for Fetal Urology (SFU) success (postoperative grade 0 or 1), and a composite of operative success and APD response. Pediatric Quality of Life Inventory (PedsQL) parent proxy scores were recorded at final follow-up.

RESULTS: Fifty-four operated renal units in 53 children were analyzed (34 LP, 20 RALP), with median follow-up of 111.4 months. RALP had longer operating time and hospitalization and more Clavien-Dindo grade I-II complications (25.0% vs 2.9%; p = 0.022). No intraoperative complications or conversions occurred. Operative success was 90.0% for RALP versus 88.2% for LP, APD response 70.0% versus 61.8%, SFU success 80.0% versus 67.6%, and composite outcome 70.0% versus 52.9%. No significant differences were detected in these four endpoints, and all corresponding 95% confidence intervals for risk differences included zero. PedsQL scores were 100 in all children. Before adding a separate capital allocation, mean direct surgical cost per procedure was USD 3521 for RALP versus USD 312 for LP. Incremental cost was USD 3,209, with an exploratory incremental cost-effectiveness ratio of USD 18,809 per additional composite outcome. Acquisition-price reductions of up to 30% did not eliminate the modeled cost difference.

CONCLUSION: No long-term effectiveness advantage of RALP was detected, and late PedsQL scores were identical, despite substantially higher direct surgical expenditure. Retrospective allocation, small sample size, and institution-specific fees limit interpretation, and equivalence cannot be claimed. These findings support context-specific case selection in established LP centers, with robotic use supported by adequate shared utilization and training, and provide foundational data for multicenter economic evaluation.