Success Of Retrograde Intrarenal Surgery Research Articles

Commentary on “Factors effecting the success of retrograde intrarenal surgery in pediatric patients with renal stones: The experience of two tertiary centers with 368 renal units”

Commentary on “Factors effecting the success of retrograde intrarenal surgery in pediatric patients with renal stones: The experience of two tertiary centers with 368 renal units”

Factors effecting the success of retrograde intrarenal surgery in pediatric patients with renal stones: The experience of two tertiary centres with 368 renal units

Currently, in the field of pediatric urology, the primary aim of surgical approaches for the treatment of renal stone disease is to provide a stoneless state through minimally invasive methods, and to prevent the damage that such stones may cause in the urinary system and stone recurrence. The aim of this study was to evaluate the efficacy and safety of RIRS and the factors affecting its success in the surgical treatment of renal stones in pediatric patients. Data from 357 pediatric and 368 renal units were collected retrospectively. The recorded parameters were age, gender, location and burden of the stone, and presence of postoperative residual stones. The stone location was the upper pole in 28 (7.6%) patients, the middle pole in 44 (12%), the pelvis in 98 (26.6%), the lower pole in 139 (37.8%), and multiple locations in 59 (16%) patients. A stoneless state was achieved in 277 (75.3%) units, while 91 units (24.7%) had residual stones at the end of the first month. In the multivariate analysis, the development of residual stones was found to be significantly associated with age (odds ratio [OR], 1.123; p=0.012) and stone location (OR, 3.142; p=0.018). RIRS is an endourological procedure with a high success rate in the achievement of a stoneless state in both pediatric and adult age groups, with an 82-100% success rate reported in various studies. A full stoneless state was achieved in 277 (75.3%) units after the initial RIRS in the present study, and full stone clearance was achieved in 304 units after the second RIRS session, with a success rate of 82.6%. A limitation of our study is that it was not performed by a single surgeon, and stone samples could not be taken from all patients for stone analysis. RIRS has also been associated with a high success rate in the endoscopic treatment of renal stones and is an efficient and safe method with a minimal rate of complications, especially in the pediatric age group.

The outcomes of flexible ureteroscopy for renal calculi of 2 cm or more with and without the use of ureteral access sheath: A retrospective study.

The rate of success of retrograde intrarenal surgery (RIRS) for treating urinary tract stones is high, and the procedure is growing in popularity. The routine use of ureteral access sheath (UAS) remains somewhat controversial. The aim of this study was to assess the efficacy and safety of employing UAS during flexible ureteroscopy for treating renal stones ≥ 2 cm. This retrospective study was accomplished from January 2021 to February 2023. From 495 consecutives flexible ureteroscopies, 112 patients had renal stones ≥ 2 cm (60 patients with the use of UAS and 52 patients without). The stone-free status was verified after 8 weeks of operation. The average diameter of the renal stones in non-UAS or UAS treated groups was 22.5 mm and 22.6, respectively. None of the groups differed significantly in terms of stone side, stone size, stone position, or Hounsfield unite but there was significant difference (p < 0.001) among two groups as regard pre-operative stenting (cases with UAS had 23.3% pre-operative stenting). It is not always necessary to use UAS in conjunction with flexible ureteroscopy and laser lithotripsy to treat renal calculi bigger than or equal two cm. Without the assistance of UAS, the surgery may be carried out successfully and safely.

Is there a superiorıty of the stone volume measured in 3-d non-contrast tomography (3-D NCCT) to the stone area in predicting the stone-freeness of the retrograde intrarenal surgery success (RIRS)

Objectives: To examine the predictive effect of preoperative measurements of stone volume (SV) against stone area (SA) on stone-free status (SF) following retrograde intrarenal surgery (RIRS). &#x0D; &#x0D; Methods: We retrospectively examined the medical records of 68 RIRS patients with renal calculi who were eligible. Patients having non-contrast computed tomography ( NCCT ) before and subsequent to RIRS were included, however staghorn stones and inability to access were omitted. SF status was determined by the absence of visible stones on the NCCT three months after RIRS. Using a software reconstruction tool using 3-D NCCT, a radiologist determined stone load characteristics, such as SA and SV. Using a logistic regression model, the assessment of potential SF status determinants was conducted. &#x0D; &#x0D; Results:Age, stone density, quantity and position of stones, usage of access sheath, failed prior Shock Wave Lithotripsy (SWL), and procedures were not substantially linked with non-SF status, however gender (p = 0.014), SA (p

Can additional variables be used to predict stone-free rates following retrograde intrarenal surgery? Anticoagulants and parenchyma thickness: a detailed examination.

The purpose of this article is to identify the factors that predict the success of retrograde intrarenal surgery (RIRS), with a focus on the effect of renal parenchymal thickness and anticoagulant use on stone-free rates. From February 2014 to April 2022, cases of kidney stones treated with RIRS at our clinic were retrospectively screened. The study included 642 cases meeting all inclusion and exclusion criteria. The patients who were observed to be stone free after a single session of RIRS were assigned to Group F, while those with residual fragments were assigned to Group R. Group F comprised 472 patients, while Group R included 170 patients. The two groups have compared certain preoperative and postoperative laboratory and radiological parameters. The infundibulopelvic angle was significantly more acute in Group R (45.63 ± 16.25 vs. 49.28 ± 15.36, p = 0.011) while patients in Group F tended to have thicker parenchyma (27.39 ± 8.38 vs. 22.88 ± 5.56, p < 0.001). In our analysis of multivariate logistic regression, stone size (OR: 1.074, 1.037-1.113; p < 0.001), lower calyceal location (OR: 0.550, 95% CI 0.364-0.831; p = 0.005), multiple numbers of stones (OR 0.254, 95% CI 0.166-0.389; p = < 0.001), the value of parenchymal thickness (OR 0.911, 95% CI 0.882-0.941; p = < 0.001) and more importantly use of anticoagulants/antiplatelets (OR 0.557, 95% CI 0.333-0.933; p = 0.026) appeared to be independent predictors of stone-free status after RIRS. Further evaluation of the data revealed that the cut-off value of the renal parenchymal thickness for an effective stone-free status in a ROC curve analysis was 24.5 with 62.9% sensitivity and 56.8% specificity (area under curve value: 0.654 [95% CI 0.608-0.699, p < 0.001]). The endourologist may be able to make more informed decisions by evaluating renal parenchymal thickness in addition to patient-related factors like anticoagulant use, which we find significantly affects outcomes, along with the stone and renal anatomy-related factors.

Recent scoring systems predicting stone-free status after retrograde intrarenal surgery; a systematic review and meta-analysis.

IntroductionSeveral scoring systems and nomograms have been developed to predict the success of retrograde intrarenal surgery. But no meta-analysis for the performance of scoring systems has yet been performed. The aim of this study was to compare predictive ability of recent scoring systems for stone-free rate of retrograde intrarenal surgery.Material and methodsPubMed and Web of Science databases were searched systematically between April and May 2021. The scoring systems which were validated externally or studied at least by two different researcher groups were selected for further analysis. Of 59 records, 14 studies met the inclusion criteria (n = 4137). Area under curve (AUC) values of selected scoring systems were pooled in random or fixed effects. The I2 test was used to quantify heterogeneity.ResultsEight, 5, 8, 4 and 3 studies included in meta-analyses for the modified Seoul National University Renal Stone Complexity Score (S-ReSC), R.I.R.S., Resorlu-Unsal Score (RUS), S.T.O.N.E., and Ito’s Nomogram, respectively. We found pooled AUC values 0.709 (95% CI 0.670–0.748), 0.704 (95% CI 0.668–0.739), 0.669 (95% CI 0.646 to 0.692), and 0.771 (95% CI 0.724 to 0.818), for first four of them, respectively. Heterogeneity was very high to pool AUC values for Ito’s nomogram.ConclusionsAlthough S.T.O.N.E. score showed higer pooled AUC value, this systematic review and meta-analysis has not revealed superiority of any scoring system. High heterogeneity between studies and dependencies between scoring systems make it difficult to design a comparative statistical model to generalize the findings. Also, limitations aside, neither scoring system has demonstrated good predictive/discriminative performance.

Factors associated with the stone-free status after retrograde intrarenal surgery in children.

Paediatric urolithiasis has a recurrent nature because it is frequently associated with metabolic or anatomical disorders or infectious conditions. The rising incidence of the disease with its recurrent nature emphasises the need for minimally invasive therapeutic options. In this study, we aimed to evaluate efficacy and factors affecting the success of retrograde intrarenal surgery (RIRS) in children. Patients who underwent RIRS were evaluated retrospectively. Two different flexible ureteroscopes (F-URS) were used (7.5F F-URS and 7.95F with a 4.9F bullet-shaped tip). Irrespective of size, all residual fragments were considered as failure. Age, stone size, stone localisation, Hounsfield Unit (HU), stone-free rate (SFR) and complications were evaluated. Forty-six patients (29 boys and 17 girls) with a median age of 70.5months (6-214months) were treated with RIRS between August 2014 and November 2019. The median operative time was 60minutes (45-120minutes). The median follow-up was 26months (3-65months). Fourteen patients had lower pole and 10 patients had multiple stones. Ureteral access sheath (UAS) was used in 16 (35%) patients. SFR was 61%.The median number of general anaesthesia was 2 (min 1, max 5). Auxiliary semirigid URS, PCNL and repeat RIRS were required in 4, 6 and 5 patients, respectively. Two patients had postoperative febrile urinary tract infection (UTI) as a complication. Age was associated with post-operative febrile UTI. Presence of stones with HU lower than 700, being operated 4.9F F-URS and without UAS were associated with better SFR. RIRS is a minimally invasive method with low complication rates in the treatment of childhood stone disease. Higher stone-free rates are obtained in low HU stones and cases in which we used 4.9 F tip F-URS.

Evaluation of the anatomical factors affecting the success of retrograde intrarenal surgery for isolated lower pole kidney stones.

Studies which examine the factors affecting success rate in kidney stones located in the lower pole as well as the effects of infundibulopelvic angle (IPA) and infundibular length (IL) have been conducted with a small number of patients. We aimed to evaluate the cut-off points of IPA and IL parameters that effect the success of retrograde intrarenal surgery (RIRS) for isolated lower pole kidney stones. This retrospective study includes 168 patients who underwent primary RIRS due to isolated lower pole kidney stones in our clinic between January 2013 and May 2020. Pre-operative demographic data, medical history, physical examination, surgery duration as well as the post-operative hospitalization time of patients specifics were obtained. According to pre-operative computed tomography (CT), stone size, stone burden, stone density, number of stones (single and multiple), stone laterality, congenital kidney abnormality, the presence of solitary kidney, parameters of IPA and IL were measured and both included in the study. All patients were divided into two groups as the successful group and the unsuccessful group according to their post-operative success. These two groups were compared in terms of pre and post-operative data. Stone burden, IPA < 42.65°, and IL > 27.5mm were specified as the independent risk factors for success of RIRS procedure. The patients for whom RIRS procedure is planned for lower pole kidney stones, stone burden, IPA, and IL should be taken into consideration to be able to predict success and it should be kept in mind that additional treatment may be required.

External validation of the R.I.R.S. scoring system to predict stone-free rate after retrograde intrarenal surgery

BackgroundThe R.I.R.S. scoring system is defined as a novel and straightforward scoring system that uses the main parameters (kidney stone density, inferior pole stones, stone burden, and renal infundibular length) to identify most appropriate patients for retrograde intrarenal surgery (RIRS). We strived to evaluate the accuracy of the R.I.R.S. scoring system in predicting the stone-free rate (SFR) after RIRS.MethodsIn our medical center, we retrospectively analyzed charts of patients who had, between September 2018 and December 2019, been treated by RIRS for kidney stones. A total of 147 patients were enrolled in the study. Parameters were measured for each of the four specified variables.ResultsStone-free status was achieved in 105 patients (71.43%), and 42 patients had one or more residual fragments (28.57%). Differences in stone characteristics, including renal infundibulopelvic angle, renal infundibular length, lower pole stone, kidney stone density, and stone burden were statistically significant in patients whether RIRS achieved stone-free status or not (P < 0.001, P: 0.005, P < 0.001, P < 0.001, P: 0.003, respectively). R.I.R.S. scores were significantly lower in patients treated successfully with RIRS than patients in which RIRS failed (P < 0.001). Binary logistic regression analyses revealed that R.I.R.S. scores were independent factors affecting RIRS success (P = 0.033). The area under the curve of the R.I.R.S. scoring system was 0.737.ConclusionsOur study retrospectively validates that the R.I.R.S. scoring system is associated with SFR after RIRS in the treatment of renal stones, and can predict accurately.

InsKid-a new mobile application (app) that measures the infundibulopelvic angle before retrograde intrarenal surgery more reliably than does other approaches: pilot study.

This study compared our program's ("InsKid") capability for measuring the infundibulopelvic angle (IPA) with existing ones. Prospectively, data from 50 patients with lower pole kidney stones with indications for retrograde intrarenal surgery (RIRS) were collected. All patients underwent computed tomography (CT)-urography. The IPA of each pelvicalyceal (PCS) unit was measured with the Elbahnasy's, Sampaio's, and "InsKid" methods. Results were compared. Finally, we compared the area under the receiver operating characteristic (ROC) curve (AUC) for predicting stone-free status after RIRS. We defined success as stone fragments ≤ 2mm on the CT scan on the first postoperative day (POD1). The stone-free rate refers to no identifiable stone fragments on the POD1 CT. Test-retest reliability and face validity were defined to estimate psychometric properties of InsKid. The success rate after first procedure was 87.5%. The average value of IPA using the Elbahnasy and Sampaio methods and our program were 85.2° ± 11.9°, 95.1° ± 10.1°, and 79.9° ± 13.0, respectively. There was a significant difference among the InsKid, Elbahnasy, and Sampaio (AUC = 0.762, 0.601, and 0.629, respectively) approaches with respect to the capability of predicting the immediate success of RIRS. Repeated measurement did not affect values of IPA (1.3° ± 0.7, p = 0.67). All specialist appreciated proposed software as highly useful (5/5). This new application reproduces the intraoperative aspects of the PCS more clearly than the other methods and also provides an easy solution for clearly defining the IPA without relying on the central axes.

PT265 - Factors affecting the success of retrograde intrarenal surgery in children

PT265 - Factors affecting the success of retrograde intrarenal surgery in children

Does Previous Failed Shockwave Lithotripsy Treatment Have an Influence on Retrograde Intrarenal Surgery Outcome?

Background: The prevalence of urolithiasis is nearly 20% and patients with urolithiasis constitute an essential part of the patients referred to the urology clinic. Many parameters should be considered for the management of renal stones and authors recommend extracorporeal shockwave lithotripsy (SWL), retrograde intrarenal surgery (RIRS), and percutaneous nephrolithotripsy (PNL), as treatment options. Among these techniques, SWL does not require general anesthesia, has 89% success rate for renal pelvic stones: 83% for upper caliceal stones, 84% for middle caliceal stones, and 68% for lower caliceal stones. In this study, we aimed to investigate whether the previously failed SWL treatment affects RIRS outcome. Methods: Patients who underwent RIRS for kidney stones between January 2012 and December 2017 in Diskapi Yildirim Beyazit Training and Research Hospital were reviewed retrospectively. Patients treated with primary RIRS (186 patients) were classified as Group 1. The outcomes of these patients were compared with those of 186 patients who underwent RIRS after failed SWL treatment using matched-pair analysis, and these patients were classified as Group 2. Results: The procedure success was defined as the sum of the stone-free and clinically insignificant residual fragments (CIRFs); final success rates were 90.3% and 91.9%, respectively. If we compare the final success rates, there was no statistically significant difference between both groups (P = .584). Conclusions: As a result, there is no negative effect of the previous unsuccessful SWL treatment on the RIRS success. Patients with CIRF should be followed up more carefully in terms of becoming symptomatic.

The Association of a Number of Anatomical Factors with the Success of Retrograde Intrarenal Surgery in Lower Calyceal Stones.

To determine anatomical factors affecting Retrograde Intrarenal Surgery (RIRS) success in the treatment of renal lower calyx stones. The results of patients were evaluated retrospectively. The patients who have preoperative intravenous urography (IVU) and computed tomography (CT) were divided into two groups as successful (S)(N=103) and unsuccessful(U) (N=29). The anatomic characteristics such as infundibulopelvic angle (IPA), infundibular length (IL), infundibular width (IW) and pelvicaliceal height (PCH) values were compared among two groups. Mean patient age was 47±13.6 years in group S and 49.5 ±11.9 years in group U. The mean stone size was 10mm (6-54mm) in group S and 19mm (8-45mm) in group U (P < .001) Mean IPA was 85.8 ±16.9 degree in group S versus 54.7 ± 11.5 degree in group U. The mean PCH was 1.9cm (0.5-4cm) in group S versus 2.3cm (0.7-3.9cm) in group U. The mean IL were 2.7 ± 0.8 cm and 3.2±0.7cm in group S and group U, respectively. The mean IWs were 0.7 cm (0.2-2.3cm) and 0.7cm (0.3-2) in group S and group U, respectively. The differences were statistically significant for IPA, PCH, IL (P < .05) while was not statistically significant for IW (P > .05). After multivariate analyses, PCH, IPA and stone size were statistically significant factors. In our study we found that IPA, PCH and stone size were significant anatomical factors affecting RIRS success in the treatment of renal lower calyx stones. The patients whose IPA, PCH and stone size valuables are unsuitable, may need multiple RIRS sessions or additionaltreatment modalities.

Unfavorable anatomical factors influencing the success of retrograde intrarenal surgery for lower pole renal calculi.

To determine the unfavorable factors, related to lower pole anatomical characteristics (LPACs), influencing the success of retrograde intrarenal surgery (RIRS) for lower pole renal calculi (LPC). We reviewed the data of 36 patients who underwent RIRS for LPC between October 2012 and October 2013. The infundibulopelvic angle (IPA), infundibular length (IL) and infundibular width (IW) were measured on preoperative intravenous urographies. On follow-up stone-free status was defined as complete clearance at the first month kidney-ureter-bladder X-ray and computed tomography if necessary. The median stone size was 10 mm (range, 5-35). The stone-free rates according to LPACs at the first month follow-up were 100% (n = 17), 57.9% (n = 11), 90% (n = 18), 62.5% (n = 10), 90.5% (n = 19) and 60% (n = 9) for patients with IPA ≥ 70°, IPA < 70º, IL < 3 cm, IL ≥ 3 cm, IW ≥ 5 mm and IW < 5 mm, respectively. While IPA and IW were associated with success of RIRS for LPC in multivariate analysis (P = .003 and P = .046, respectively), only IW was found to be a significant factor after applying multivariate analysis (P = .05). The results of our study demonstrated that only IW had a significant effect on the success rate of RIRS for LPC.

S304: Effect of previous shockwave lithotripsy on the success of retrograde intrarenal surgery

S304: Effect of previous shockwave lithotripsy on the success of retrograde intrarenal surgery

Residual Fragments Following Ureteroscopic Lithotripsy: Incidence and Predictors on Postoperative Computerized Tomography

Residual fragments following ureteroscopy for calculi may contribute to stone growth, symptoms or additional interventions. We reviewed our experience with ureteroscopy for calculus disease to define the incidence and establish factors predictive of residual fragments. Records associated with 667 consecutive ureteroscopic lithotripsy procedures for upper urinary calculi were reviewed. In 265 procedures (40%) computerized tomography was done between 30 and 90 days postoperatively. They comprised the study group. Residual fragments were defined as any residual ipsilateral stone greater than 2 mm. Included in the study were 121 men and 127 women with a mean age of 47 years. Mean target stone diameter was 7.6 mm. The stone location was the kidney in 30% of cases, ureter in 50%, and kidney and ureter in 20%. Residual fragments were detected on computerized tomography after 101 of 265 procedures (38%). Pretreatment stone size was associated with residual fragments at a rate of 24%, 40% and 58% for stones 5 or less, 6 to 10 and greater than 10 mm, respectively (p <0.001). Additionally, stone location in the kidney (p <0.001) or the kidney and ureter (p = 0.044), multiple calculi (p = 0.003), longer operative time (p = 0.008) and exclusive use of flexible ureteroscopy (p = 0.029) were associated with residual fragments. In a multivariate model only pretreatment stone diameter greater than 5 mm was independently associated with residual fragments after ureteroscopy (diameter 6 to 10 and greater than 10 mm OR 2.03, p = 0.03 and OR 3.74, p = 0.003, respectively). Of patients who underwent ureteroscopic lithotripsy for calculi 38% had residual fragments by computerized tomography criteria, including more than 50% with stones 1 cm or greater. Such data may guide expectations regarding the success of ureteroscopy in attaining stone-free status.

The Impact of Pelvicaliceal Anatomy on the Success of Retrograde Intrarenal Surgery in Patients With Lower Pole Renal Stones

To evaluate the impact of pelvicaliceal anatomy on the success of retrograde intrarenal surgery (RIRS) for lower pole renal stones and determine which of these factors can be used to select patients who will benefit from RIRS. We evaluated 67 patients who underwent RIRS between 2009 and 2010 for isolated lower pole renal stones. The infundibular length (IL), infundibular width (IW), pelvicaliceal height (PCH), and infundibulopelvic angle (IPA) were measured by preoperative intravenous urogram. Success was defined as either complete clearance or clearance with insignificant residual fragments≤3 mm in size at 2-months follow-up. Mean IL was 26.7±7.9 and 28.2±5.3 mm, mean PCH was 20.7±6.6 and 23.2±4.9 mm in stone-free and non-stone-free patients, respectively. These were slightly larger in the non-stone-free group but not statistically significant (P=.140 and P=.072, respectively). Mean IW was 5.8±3.5 and 5.6±2.2 mm in stone-free and non-stone-free patients, respectively, which had no significant impact on the stone-free rate (P=.719). There were significant differences between the groups in terms of stone length (P=.001) and IPA (P=.003). The mean IPA was 49.37±11.83 and 37.61±13.22 mm in stone-free and non-stone-free patients, respectively. In addition to the influence of stone size, lower pole anatomy, especially IPA, has a significant impact on stone clearance for lower pole stones after RIRS.