Flexible ureteroscopy across calyceal locations: impact of ureteroscope caliber and lower-pole anatomy on stone-free outcomes: Sheathless RIRS: Calyx Anatomy and Scope Size
BMC Urology, cilt.26, sa.1, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 26 Sayı: 1
- Basım Tarihi: 2026
- Doi Numarası: 10.1186/s12894-026-02118-0
- Dergi Adı: BMC Urology
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CINAHL, EMBASE, MEDLINE, Directory of Open Access Journals, Biomedical Reference Collection: Corporate Edition (EBSCO), Health Research Premium Collection (ProQuest)
- Anahtar Kelimeler: Flexible ureteroscopy, Infundibulopelvic angle, Kidney calculi, Ureteroscope, Ureteroscopy
- Sağlık Bilimleri Üniversitesi Adresli: Evet
Özet
Background: This study compared the clinical performance of 7.5 F and 9 F digital flexible ureteroscopes in sheathless retrograde intrarenal surgery (RIRS), with a particular focus on how ureteroscope caliber interacts with lower-pole anatomy to influence stone-free outcomes. Methods: This retrospective study included patients who underwent sheathless RIRS for single renal stones measuring 10–20 mm between October 2023 and August 2025 using either a 7.5–9 F digital flexible ureteroscope. All procedures were performed by three experienced surgeons under a standardized protocol. Stone-free status (SFR) was defined as residual fragments ≤ 4 mm on 1-month non-contrast CT. Perioperative parameters and complications were compared between groups. A prespecified lower-pole subgroup analysis examined the relationship between IPA and clearance using logistic regression and ROC analysis. Results: Seventy patients were analyzed (7.5 F = 37; 9 F = 33). Overall SFRs were 78.4% and 69.7% for the 7.5 F and 9 F groups, respectively (p = 0.42). Complication rates were low and comparable. In the lower-pole subgroup, the 7.5 F scope achieved a significantly higher SFR (64.7% vs. 23.1%, p = 0.03). Multivariable analysis identified ureteroscope caliber (adjusted OR = 5.76, p = 0.036) and IPA (adjusted OR = 0.92 per degree, p = 0.017) as independent predictors of lower-pole clearance, with moderate discriminative ability for IPA (AUC = 0.682). Conclusion: In sheathless RIRS, smaller-caliber ureteroscopes were associated with higher stone-free rates for lower-pole stones, while overall outcomes were comparable between groups. Lower-pole anatomy was significantly associated with stone-free outcomes.