Comparative evaluation of the efficacy and safety of antegrade minimally percutaneous nephrolithotomy and retrograde intrarenal surgery in the treatment of upper ureteral impacted stones: a retrospective cohort study

Objective: To compare the safety and efficacy of retrograde intrarenal surgery (RIRS) vs minimally invasive percutaneous nephrolithotomy (mPCNL) in the minimal invasive management of impacted upper ureteral stones along with the evaluation of predictive radiological parameters.
Patients and methods: A retrospective analysis was done in 124 patients, undergoing RIRS (n:61) and mPCNL (n:63) for the management of impacted upper ureteral stones. Both operative (success and complication rates, operative time, postoperative hospital stay) and radiological (ureteral wall thickness, UWT), stone volume (SV), and stone density (Hounsfield unit, HU) factors were all evaluated and recorded. Comparative evaluation of stone free status in both groups was done following 72 hours and 4-weeks after the procedures to calculate the primary stone-free as well as final stone clearance rates. Additionally, the outcomes of RIRS group were categorized based on the intraoperative findings (presence or absence of stone encasement by a polyp) and preoperative radiological parameters. All data were well analyzed for statistical significance. A significance level of p<0.05 was considered statistically significant.
Results: Baseline patient and stone related characteristics were similar in two groups. The success rates after a single session for RIRS and mPCNL were 73.77% and 93.65%, respectively (p=0.003), indicating a significantly higher success rate for mPCNL. However the final stone clearance rates were 96.72% and 100.00%, respectively (p=0.147), with no significant difference observed among the groups. The RIRS group demonstrated higher rate of need for auxiliary treatments (p<0.001), shorter hospital stay (p<0.001) and lower incidence of bleeding (p<0.001). Radiological evaluation showed no significant differences in stone volume, HU and UWT values between patients with and without residual stones after RIRS (Pstone volume = 0.151, PHU = 0.451, PUWT = 0.083). Similarly, no significant differences were observed with respect to these values also in mPCNL patients, (Pstone volume = 0.532, PHU = 0.455, PUWT = 0.658). However, a significant difference has been noted regarding the mean value of UWT between the stones surrounded by a polypoid alterations and the ones without such changes with values 5.23 ± 0.65 mm, to 4.10 ± 0.82 mm, respectively (p=0.001).
Conclusions: Our results demonstrated that antegrade mPCNL achieves faster stone clearance and a lower re-treatment rate without serious complications in impacted upper ureteric stones. However, RIRS could be a valuable and safe alternative with comparable success rates particularly in cases with contraindications to or unwillingness for mPCNL. Preoperative assessment of ureteral wall thickness (UWT) value may be a good predictor for the possible tissue changes in ureteral wall at stone site to guide the decision making of the most appropriate surgical approach.

Türk C, Petrík A, Sarica K, et al. EAU Guidelines on interventional treatment for urolithiasis. Eur Urol. 2016; 69:475-82. DOI: https://doi.org/10.1016/j.eururo.2015.07.041

Knoll T, Wezel F, Michel MS, et al. Do patients benefit from miniaturized tubeless percutaneous nephrolithotomy? A comparative prospective study. J Endourol. 2010; 24:1075-9. DOI: https://doi.org/10.1089/end.2010.0111

Sunaryo PL, May PC, Holt SK, et al. Ureteral strictures following ureteroscopy for kidney stone disease: a population-based assessment. JPN J Urol. 2022; 208:1268-75. DOI: https://doi.org/10.1097/JU.0000000000002929

May PC, Hsi RS, Tran H, et al. The morbidity of ureteral strictures in patients with prior ureteroscopic stone surgery: multi-institutional outcomes. J Endourol. 2018; 32:309-14. DOI: https://doi.org/10.1089/end.2017.0657

Sammon JD, Ghani KR, Karakiewicz PI, et al. Temporal trends, practice patterns, and treatment outcomes for infected upper urinary tract stones in the united states. Eur Urol. 2013; 64:85-92. DOI: https://doi.org/10.1016/j.eururo.2012.09.035

Schuster TG, Hollenbeck BK, Faerber GJ, et al. Complications of ureteroscopy: analysis of predictive factors. JPN J Urol. 2001;166:538-40. DOI: https://doi.org/10.1016/S0022-5347(05)65978-2

Ruhayel Y, Tepeler A, Dabestani S, et al. Tract Sizes in miniaturized percutaneous nephrolithotomy: a systematic review from the european association of urology urolithiasis guidelines panel. Eur Urol. 2017; 72:220-35. DOI: https://doi.org/10.1016/j.eururo.2017.01.046

Clayman R. From knife to needle to nothing: The waning of the wound. Int Braz J Urol. 2001;27.

Ghani KR, Andonian S, Bultitude M, et al. Percutaneous nephrolithotomy: update, trends, and future directions. Eur Urol. 2016; 70:382-96. DOI: https://doi.org/10.1016/j.eururo.2016.01.047

Preminger GM, Tiselius HG, Assimos DG, et al. 2007 Guideline for the management of ureteral calculi. Eur Urol. 2007; 52:1610-31. DOI: https://doi.org/10.1016/j.eururo.2007.09.039

Assimos D, Krambeck A, Miller NL, et al. Surgical management of stones: american urological association/endourological society guideline, part I. JPN J Urol. 2016; 196:1153-60. DOI: https://doi.org/10.1016/j.juro.2016.05.090

Aboumarzouk OM, Somani BK, Monga M. Flexible ureteroscopy and holmium:YAG laser lithotripsy for stone disease in patients with bleeding diathesis: a systematic review of the literature. Int Braz J Urol. 2012; 38:298-305; discussion 6. DOI: https://doi.org/10.1590/S1677-55382012000300002

Roberts WW, Cadeddu JA, Micali S, et al. Ureteral stricture formation after removal of impacted calculi. JPN J Urol. 1998;159:723-6. DOI: https://doi.org/10.1016/S0022-5347(01)63711-X

Soderberg L, Ergun O, Ding M, et al. Percutaneous nephrolithotomy versus retrograde intrarenal surgery for treatment of renal stones in adults. Cochrane DB Syst Rev. 2023;11:Cd013445. DOI: https://doi.org/10.1002/14651858.CD013445.pub2

Akman T, Binbay M, Ozgor F, et al. Comparison of percutaneous nephrolithotomy and retrograde flexible nephrolithotripsy for the management of 2-4 cm stones: a matched-pair analysis. BJU Int. 2012; 109:1384-9. DOI: https://doi.org/10.1111/j.1464-410X.2011.10691.x

Dean NS, Millan B, Uy M, et al. Ureteral wall thickness is an effective predictor of ureteral stone impaction and management outcomes: a systematic review and meta-analysis. JPN J Urol. 2023;210:430-7. DOI: https://doi.org/10.1097/JU.0000000000003561

Lai S, Jiao B, Diao T, et al. Optimal management of large proximal ureteral stones (>10 mm): A systematic review and meta-analysis of 12 randomized controlled trials. Int J Surg. 2020; 80:205-17. DOI: https://doi.org/10.1016/j.ijsu.2020.06.025

Wu C, Hua LX, Zhang JZ, et al. Comparison of renal pelvic pressure and postoperative fever incidence between standard- and minitract percutaneous nephrolithotomy. Kaohsiung J Med Sci. 2017;33:36-43. DOI: https://doi.org/10.1016/j.kjms.2016.10.012

Yang Z, Song L, Xie D, et al. Comparative study of outcome in treating upper ureteral impacted stones using minimally invasive percutaneous nephrolithotomy with aid of patented system or transurethral ureteroscopy. Urology. 2012; 80:1192-7. DOI: https://doi.org/10.1016/j.urology.2012.08.045

Sakr A, Salem E, Kamel M, et al. Minimally invasive percutaneous nephrolithotomy vs standard PCNL for management of renal stones in the flank-free modified supine position: single-center experience. Urolithiasis. 2017; 45:585-9. DOI: https://doi.org/10.1007/s00240-017-0966-1

Gökce M, Akpinar Ç, Obaid K, et al. Comparison of retrograde ureterorenoscopy (URS) and percutaneous anterograde ureteroscopy for removal of impacted upper ureteral stones >10 mm in the elderly population. Int Braz J Urol. 2021; 47:64-70. DOI: https://doi.org/10.1590/s1677-5538.ibju.2019.0638

Goodman TM. Ureteroscopy with pediatric cystoscope in adults. Urology. 1977; 9:394. DOI: https://doi.org/10.1016/0090-4295(77)90213-8

Yencilek F, Canguven O, Albayrak S, et al. A comparison of shock wave lithotripsy, semirigid and flexible ureteroscopy in the management of proximal ureteral calculi. Turk J Urol. 2009;35:101-107.

Best SL, Nakada SY. Flexible ureteroscopy is effective for proximal ureteral stones in both obese and nonobese patients: a two-year, single-surgeon experience. Urology. 2011; 77:36-9. DOI: https://doi.org/10.1016/j.urology.2010.05.001

Lildal SK, Andreassen KH, Baard J, et al. Consultation on kidney stones, Copenhagen 2019: aspects of intracorporeal lithotripsy in flexible ureterorenoscopy. World J Urol. 2021; 39:1673-82. DOI: https://doi.org/10.1007/s00345-020-03481-9

Prabhakar M. Retrograde ureteroscopic intrarenal surgery for large (1.6-3.5 cm) upper ureteric/renal calculus. Indian J Urol. 2010; 26:46-9. DOI: https://doi.org/10.4103/0970-1591.60443

Multescu R, Geavlete B, Georgescu D, et al. Holmium laser intrarenal lithotripsy in pyelocaliceal lithiasis treatment: to dust or to extractable fragments? Chirurgia-Bucharest. 2014;109:95-8.

Sun H, Zhang Z, Yuan J, et al. Safety and efficacy of minimally invasive percutaneous nephrolithotomy in the treatment of patients with medullary sponge kidney. Urolithiasis. 2016;44:421-6. DOI: https://doi.org/10.1007/s00240-015-0853-6

de la Rosette JJ, Opondo D, Daels FP, et al. Categorisation of complications and validation of the Clavien score for percutaneous nephrolithotomy. Eur Urol. 2012; 62:246-55. DOI: https://doi.org/10.1016/j.eururo.2012.03.055

Xu G-b, Li X-z, He Y-z, et al. Ten years experience in treatment of upper urinary calculi withRIRS: clinical analysis of 10 413 cases in single center. Chin J Endosc. 2020; 26:64-8.

Popiolek M, Lidén M, Georgouleas P, et al. Radiological signs of stone impaction add no value in predicting spontaneous stone passage. Urolithiasis. 2024; 52:114. DOI: https://doi.org/10.1007/s00240-024-01604-0

Yamashita S, Kohjimoto Y, Iguchi T, et al. Ureteral wall volume at ureteral stone site is a critical predictor for shock wave lithotripsy outcomes: comparison with ureteral wall thickness and area. Urolithiasis. 2020; 48:361-8. DOI: https://doi.org/10.1007/s00240-019-01154-w