Can flexible nephroscopy, inspection, and calyceal examination (NICE) post suction mini percutaneous nephrolithotomy improve zero and overall stone free rate? an EAU endourology and AUSET collaboration study

Xiao K., Gauhar V., Castellani D., Kalathia J., Gadzhiev N., Malkhasyan V., ...More

World Journal of Urology, vol.44, no.1, 2026 (SCI-Expanded, Scopus) identifier identifier

  • Publication Type: Article / Letter
  • Volume: 44 Issue: 1
  • Publication Date: 2026
  • Doi Number: 10.1007/s00345-026-06303-6
  • Journal Name: World Journal of Urology
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Gender Studies Database, MEDLINE
  • Keywords: Nephroscopy, inspection, and calyceal examination (NICE), Prospective multicenter study, Residual fragments, Stone free rate, Suction mini-PCNL
  • Ankara University Affiliated: Yes

Abstract

Abstract: To assess if adjunct flexible Nephroscopy, Inspection, and Calyceal Examination (NICE) improves stone-free rate (SFR) after suction mini-percutaneous nephrolithotomy (SM-PCNL). This prospective multicenter study included 1534 SM-PCNL patients (March-November 2024) from 30 centers across 21 countries. Post intervention, patients underwent calyceal inspection via fluoroscopy alone (Group 1, n = 1022) or fluoroscopy plus NICE (performed via antegrade flexible nephroscopy or retrograde ureteroscopy) (Group 2, n = 512) to check for per operative injury and stone clearance. Stone-free status (SFS) was assessed by 30-day non-contrast CT (NCCT): Grade A (zero residual fragments, ZRF), B (single ≤4 mm), or C (> 4 mm/multiple). Group 2 had larger stones (diameter: 22 mm vs. 19 mm, volume: 2100 mm³ vs. 1498 mm³, p < 0.001), higher Guy’s stone scores (Grade 2–4: 54.5% vs. 43.9%, p < 0.001), and longer operative times (55 vs. 42 min, p < 0.001). Notably, Group 2 exhibited significantly lower ZRF (75.6% vs. 86.6%), higher Grade B (18.9% vs. 11.9%) and Grade C fragments (7.0% vs. 3.7%, p < 0.001). Multivariate analysis revealed the odds of ZRF did not improve with NICE (OR 0.69, 95%CI 0.50–0.95; p = 0.024) and increased 30-day reinterventions (4.5% vs. 1.5%; p < 0.001). Complications were comparable (10.5% vs. 11.3%, p = 0.677). Intraoperative SFS assessment correlated better with NCCT in Group 1 (81.2% vs. 76.0%; p = 0.017), with superior accuracy in identifying ZRF (90.4% vs. 84.1%; p = 0.001). In SM-PCNL, the use of NICE in complex cases was not associated with improved ZRF or overall SFR (Grade A + B) compared to fluoroscopy alone, despite its preferential use in more challenging scenarios. Fluoroscopy alone showed better intraoperative-NCCT correlation for residual fragments and shorter operative times. Based on these findings, routine use of NICE in SM-PCNL is not supported. Its selective application may be considered in complex cases where direct visualisation is deemed crucial.