Objective: Our study aimed to investigate the effect of lower pole localization in solitary stones smaller than 2 cm on pediatric retrograde intrarenal surgery (RIRS) outcomes compared to other localizations. Materials and Methods: Data from patients who underwent RIRS in a university hospital between January 2021 and June 2024 were retrospectively analyzed. The study included 69 patients under 18 years of age with single stones less than 2 cm and whose data were available. Patients were divided into two groups according to kidney stone localization: lower pole (Group 1) and other localizations (Group 2). Demographic data, clinical characteristics, stone-related data, and perioperative and postoperative data of the patients were statistically compared in both groups. Results: The study enrolled 69 patients with a mean age of 7±4.4 (1-17) years and a mean stone size of 11±3.3 (5-20) mm. There were 21 patients in Group 1 and 48 patients in Group 2. The patient's demographic data and clinical characteristics in both groups were similar. The groups' stone size, side, and density were similar (p=0.58, 0.58, and 0.63, respectively). The prestenting rate was statistically significantly higher in Group 1 than in Group 2 (76.2% vs 50%, p=0.04). No statistically significant difference was detected between the groups in access sheath use, operation time, fluoroscopy time, the stone-free rate on 1st day and 3rd month, or auxiliary procedures (p=0.69, 0.95, 0.60, 0.97, 0.27, and 0.28, respectively). The complication rates were similar in both groups (p=0.28). No high-grade or anesthesiarelated complications were observed in any of the patients. Conclusion: The lower pole localization does not affect surgical parameters, except for the prestenting rate, in single stones smaller than 2 cm. Considering that prestenting is performed under general anesthesia in the pediatric population, lower pole stones may increase the number of anesthesia sessions, radiation exposure, and hospitalizations.
Cite this Article As :
Kilinc MT, Piskin MM, Cavdar OF, Gunes B, Ozkent MS. Comparison of Pediatric Retrograde Intrarenal Surgery Outcomes in Less than 2 cm Single Stones: Lower Pole and Other Localizations. Selcuk Med J 2025;41(4): 176-181
1. Carmen Tong CM, Ellison JS, Tasian GE. Pediatric Stone Disease: Current Trends and Future Directions. Urol Clin North Am. 2023;50(3):465-75. DOI: 10.1016/j.ucl.2023.04.009
2. Dwyer ME, Krambeck AE, Bergstralh EJ, et al. Temporal trends in incidence of kidney stones among children: a 25-year population based study. J Urol. 2012;188(1):247-52. DOI: 10.1016/j.juro.2012.03.021
3. Servais A, Thomas K, Dello Strologo L, et al. Cystinuria: clinical practice recommendation. Kidney Int. 2021;99(1):48-58. DOI: 10.1016/j.kint.2020.06.035
4. Radmayr C, Bogaert G, Bujons A, et al. Guidelines Associates: Kennedy UK, Gnech M, Skott M, van Uitert A, Zachou A. Guidelines Office: Bezuidenhout C. Guidelines on Paediatric Urology 2024; ISBN 978-94-92671-23-3.
5. Sultan S, Aba Umer S, Ahmed B, et al. Update on Surgical Management of Pediatric Urolithiasis. Front Pediatr. 2019;7:252. DOI: 10.3389/fped.2019.00252
6. Ishii H, Griffin S, Somani BK. Ureteroscopy for stone disease in the paediatric population: a systematic review. BJU Int. 2015;115(6):867-73. DOI: 10.1111/bju.12927
7. He Q, Xiao K, Chen Y, et al. Which is the best treatment of pediatric upper urinary tract stones among extracorporeal shockwave lithotripsy, percutaneous nephrolithotomy and retrograde intrarenal surgery: a systematic review. BMC Urol. 2019;19(1):98. DOI: 10.1186/s12894-019-0520-2
8. Halinski A, Steyaert H, Wojciech M, et al. Endourology Methods in Pediatric Population for Kidney Stones Located in Lower Calyx: FlexURS vs. Micro PCNL (MicroPERC®). Front Pediatr. 2021;9:640995. DOI: 10.3389/fped.2021.640995
9. Quiroz Y, Somani BK, Tanidir Y, et al. Retrograde Intrarenal Surgery in Children: Evolution, Current Status, and Future Trends. J Endourol. 2022;36(12):1511-21. DOI: 10.1089/end.2022.0160
10. Kilicarslan H, Kaynak Y, Kordan Y, et al. Unfavorable anatomical factors influencing the success of retrograde intrarenal surgery for lower pole renal calculi. Urol J. 2015;12(2):2065-68. DOI: 10.22037/uj.v12i2.2730
11. Ozkent MS, Piskin MM, Balasar M, et al. Is Retrograde Intrarenal Surgery as Safe for Children as It Is for Adults? Urol Int. 2021;105(11-12):1039-45. DOI: 10.1159/000517290
12. Kahraman O, Dogan HS, Asci A, et al. Factors associated with the stone-free status after retrograde intrarenal surgery in children. Int J Clin Pract. 2021;75(10):e14667. DOI: 10.1111/ijcp.14667
13. Castellani D, Somani BK, Ferretti S, et al. Role of Preoperative Ureteral Stent on Outcomes of Retrograde Intra-Renal Surgery (RIRS) in Children. Results From a Comparative, Large, Multicenter Series. Urology. 2023;173:153-58. DOI: 10.1016/j.urology.2022.11.019
14. Kumar A, Vasudeva P, Nanda B, et al. A Prospective Randomized Comparison Between Shock Wave Lithotripsy and Flexible Ureterorenoscopy for Lower Caliceal Stones ≤2 cm: A Single-Center Experience. J Endourol. 2015;29(5):575-79. DOI: 10.1089/end.2013.0473
15. Juliebø-Jones P, Gauhar V, Lim EJ, et al. Outcomes and considerations for retrograde intrarenal surgery (RIRS) in the setting of multiple and large renal stones (>15 mm) in children: Findings from multicentre and real-world setting. BJUI Compass. 2024;5(6):558-63. DOI: 10.1002/bco2.357
16. Cannon GM, Smaldone MC, Wu HY, et al. Ureteroscopic management of lower-pole stones in a pediatric population. J Endourol. 2007;21(10):1179-82. DOI: 10.1089/end.2007.9911
17. Cohen J, Cohen S, Grasso M. Ureteropyeloscopic treatment of large, complex intrarenal and proximal ureteral calculi. BJU Int. 2013;111(3 Pt B):E127-31. DOI: 10.1111/j.1464-410X.2012.11352.x
18. Inoue T, Murota T, Okada S, et al. Influence of Pelvicaliceal Anatomy on Stone Clearance After Flexible Ureteroscopy and Holmium Laser Lithotripsy for Large Renal Stones. J Endourol. 2015;29(9):998-1005. DOI: 10.1089/end.2015.0071
19. Kaygısız O, Aydın YM, Turan L, et al. Factors Affecting Stone-freeness in the Initial Session of RIRS in Childhood Kidney Stones. J Urol Surg 2024;11(1):1-6. DOI: 10.4274/jus.galenos.2023.2023.0005
20. Azili MN, Ozcan F, Tiryaki T. Retrograde intrarenal surgery for the treatment of renal stones in children: factors influencing stone clearance and complications. J Pediatr Surg. 2014;49(7):1161-65. DOI: 10.1016/j.jpedsurg.2013.12.023
21. Unsal A, Resorlu B. Retrograde intrarenal surgery in infants and preschool-age children. J Pediatr Surg. 2011;46(11):2195-99. DOI: 10.1016/j.jpedsurg.2011.07.013
22. Kourmpetis V, Dekalo S, Levy N, et al. Toward Respiratory-Gated Retrograde Intrarenal Surgery: A Prospective Controlled Randomized Study. J Endourol. 2018;32(9):812-17. DOI: 10.1089/end.2018.0231
23. Yuan Y, Liang YN, Li KF, et al. A meta-analysis: retrograde intrarenal surgery vs. percutaneous nephrolithotomy in children. Front Pediatr. 2023;11:1086345. DOI: 10.3389/fped.2023.1086345
24. Berrettini A, Boeri L, Montanari E, et al. Retrograde intrarenal surgery using ureteral access sheaths is a safe and effective treatment for renal stones in children weighing <20 kg. J Pediatr Urol. 2018;14(1):59.e1-.e6. DOI: 10.1016/j.jpurol.2017.09.011
25. Alzahrani MA, Alghuyaythat WKZ, Alsaadoon BMB, et al. Comparative efficacy of different surgical techniques for pediatric urolithiasis-a systematic review and meta-analysis. Transl Androl Urol. 2024;13(7):1127-44. DOI: 10.21037/tau-23-676
26. Selvi I, Hajiyev P, Ekberli G, et al. The effects of primary and recurrent pediatric urological surgeries on parental anxiety levels. J Pediatr Urol. 2020;16(5):652.e1-.e9. DOI: 10.1016/j.jpurol.2020.07.036
27. Yuruk E, Tuken M, Gonultas S, et al. Retrograde intrarenal surgery in the management of pediatric cystine stones. J Pediatr Urol. 2017;13(5):487.e1-.e5. DOI: 10.1016/j.jpurol.2017.01.015
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Keywords
Lower Pole, Pediatric RIRS, Renal Stones, RIRS Outcomes