Efficacy Of Retrograde Intrarenal Surgery Research Articles

Lower Pole Stones Are Associated with Low Stone-Free Rates in Retrograde Intrarenal Surgery: A Myth or Fact? – A Matched Case-Control Study from the RIRSearch Group

Introduction: There are conflicting results in the literature regarding the efficacy of retrograde intrarenal surgery (RIRS) in lower pole stones. This study aimed to evaluate RIRS outcomes in lower pole stones by forming matched case-control groups. Methods: The data of 491 patients who were diagnosed with kidney stones and underwent RIRS were retrospectively included in the study. A total of 209 patients with lower pole stones (Group 1) and 282 patients with pelvic stones (Group 2) were matched at a 1:1 ratio in terms of stone burden, stone density, preoperative double-J stenting status, and a previous history of shock wave lithotripsy, yielding 159 patients in each group. A computed tomography scan was performed to evaluate the stone-free status. The primary outcome was stone-free status 1 month after RIRS. Results: After case-control matching, the median age was 49 years (interquartile range [IQR]: 40–58) in Group 1 and 50 years (IQR: 35–60) in Group 2 (p = 0.388). The median stone burden values of Group 1 and Group 2 were 415.3 mm3 (IQR: 176.1–858.2) and 503.3 mm3 (IQR: 282.5–864), respectively (p = 0.100). After RIRS, stone-free status was achieved by 126 of the 159 (79.2%) in Group 1 and 133 of the 159 (83.6%) patients in Group 2 (p = 0.387). The groups were similar in terms of perioperative complications (4.4% in Group 1 and 3.8% in Group 2, p = 0.777), postoperative complications (13.8% in Group 1 and 10.3% in Group 2, p = 0.393), and median operation time (60 min in both, p = 0.230). A longer median fluoroscopy time was noted in Group 1 compared to Group 2 (26 s and 3 s, respectively, p = 0.013). Conclusions: Stone-free rates and complications were comparable between the patients with lower pole and pelvic stones after RIRS. However, lower pole stones are associated with longer fluoroscopy time. RIRS can be performed effectively for the treatment of lower pole stones.

Comparative study between retrograde intrarenal surgery and ultrasound- guided shock wave lithotripsy for treatment of 1 to 2 cm radiolucent lower calyceal stones.

The objective is to compare the safety and efficacy of retrograde intrarenal surgery (RIRS) and ultrasound-guided (US-guided) shock wave lithotripsy (SWL) for the treatment of radiolucent lower pole calculi of 1-2 cm. This prospective randomized study was performed at our tertiary care urology institute of Benha University Hospitals; cases were randomized either to undergo RIRS (Group A) or US-guided SWL with a triple focus system (Group B). The safety and effectiveness of both therapies were compared using new criteria for stone-free rate (SFR): Grade A (absolutely stone free), Grade B (≤2 mm fragments), and Grade C (>2 mm up to 4 mm fragments), fluoroscopy time, operative time, auxiliary procedures, retreatment, and complications. Out of 100 patients, 92 were eligible for this study. RIRS had a higher SFR of 88.9% compared to SWL, 72.3% (P = 0.045). Furthermore, stone-free classification significantly differed between the studied groups (P < 0.001), with Grade A being significantly higher in Group A. Conversely, Grades B and C were lower in Group A. On the other hand, operative and fluoroscopy times were significantly reduced with SWL (P = 0.004 and < 0.001, respectively). While complications did not significantly differ between the two groups (P = 0.340), a significant distinction was observed in terms of the Clavien-Dindo classification. RIRS is an effective and safe option for treating radiolucent lower calyceal stones of ≤2 cm, with a greater SFR and lower need for auxiliary operations. However, Sono SWL is a cost-effective alternative that can achieve a comparable success rate after retreatment sessions.

The Feasibility and Outcomes of Retrograde Intrarenal Surgery to Treat Staghorn Renal Calculi

Objective: To study the safety and efficacy of retrograde intrarenal surgery (RIRS) in patients with staghorn stones. Materials and Methods: This retrospective observational study was carried out between May 2016 and October 2020, which is when we performed RIRS in staghorn stone patients. Medical records of all patients with this condition in the database of Siriraj Hospital were reviewed. A total of 35 patients were eligible for this study. Descriptive statistics were used to assess the safety and efficacy of RIRS in patients with staghorn stones. Results: In total, 31.43% of patients were stone-free after the first round of RIRS and 59.55% achieved stone-free status after the second procedure. The stone-free rate did not increase after a second round of RIRS. The median size of all staghorn stones was 3.1 cm. Unfortunately, we found two sepsis patients in this study. We also found eight events of minor complications, including fever and minimal ureteric injury in 54 sessions of RIRS we performed. However, no major injuries or bleeding requiring blood transfusion was identified. Conclusion: Percutaneous nephrolithotomy (PCNL) is still considered the first-line therapy for kidney stones over two centimeters with a favorable stone-free rate. But, in some patients with limitations such as uncorrectable coagulopathies, impaired renal function, single kidney, and morbid obesity, RIRS is a good choice to reduce the likelihood of serious complications and have an acceptable stone-free rate. However, a prospective study should be performed to confirm these findings.

The efficacy of retrograde intra-renal surgery (RIRS) for lower pole stones: results from 2946 patients

PurposeTo evaluate the perioperative outcomes of retrograde intra-renal surgery (RIRS) for lower pole stones (LPS) and factors affecting stone-free rate (SFR).MethodsData from 20 centers were retrospectively reviewed. Inclusion criteria were adult patients, normal renal anatomy, and LPS. Exclusion criteria were bilateral surgery, concomitant surgery for ureteral stones. SFR was defined as a single residual fragment (RF) ≤ 2 mm and evaluated 3-months after surgery. A multivariable logistic regression analysis was performed to assess factors associated with RF. Statistical significance was set at p value < 0.05.Results2946 patients were included. Mean age and stone size were 49.9 years 10.19 mm, with multiple LPS in 61.1% of cases. Total operation and laser time were 63.89 ± 37.65 and 17.34 ± 18.39 min, respectively. Mean hospital stay was 3.55 days. Hematuria requiring blood transfusion and fever/urinary infections requiring prolonged antibiotics occurred in 6.1% and 169 5.7% of cases, while sepsis with intensive-care admission in 1.1% of patients. On multivariate analysis, Multiple stones (OR 1.380), stone size (OR 1.865), and reusable ureteroscopes (OR 1.414) were significantly associated with RF, while Thulium fiber laser (TFL) (OR 0.341) and pre-stenting (OR 0.750) were less likely associated with RF.ConclusionsRIRS showed safety and efficacy for LPS with a mean diameter of 10 mm. This procedure can achieve a satisfactory SFR in pre-stented patients with a single and smaller stone, particularly with TFL use.

Retrograde intrarenal surgery for kidney stones larger than two centimetres

According to the guidelines, percutaneous nephrolithotomy is the main treatment for patients with kidney stones larger than 2 cm. However, many studies have recently been published describing the safety and efficacy of retrograde intrarenal surgery (RIRS) in the treatment of patients with kidney stones of similar size. This paper reviews the literature on the use of RIRS in the treatment of patients with kidney stones larger than 2 cm. The study aims to evaluate the safety and efficacy of RIRS in the treatment of kidney stones larger than 2 cm. Such indicators as the duration of surgical treatment, stone-free rate, intra- and postoperative complications were evaluated. Also, the history of the development of ureteroscopy as a diagnostic and therapeutic method for diseases of the upper urinary tract is briefly reviewed. The material was searched in the PubMed, Scopus, Web of Science, and Google Scholar databases.

MP038 - Safety and efficacy of retrograde intrarenal surgery in elderly patients

MP038 - Safety and efficacy of retrograde intrarenal surgery in elderly patients

Could "Retrograde Intrarenal Surgery" be Used as an Efficient Technique in the Treatment of Calyceal Diverticula Stones.

To evaluate the efficacy of retrograde intrarenal surgery (RIRS) and holmium laser lithotripsy in the treatment of symptomatic renal calyceal diverticular (CD) stones. A case series. Department of Urology, Hisar Intercontinental Hospital, from 2008 and 2019. Patients who underwent holmium laser lithotripsy with RIRS to manage symptomatic CD stones were evaluated retrospectively. Demographics, stone size, operation and hospital stay duration, the success of treatment and complications were noted. Among the 30 treated patients, 13 patients were female and 17 were male. The mean age was 45.4 ± 11.9 (26-64), the stone diameter was 14.4 ± 4.1 mm, operation time was 70.47±35.7 (35-155) minutes, and mean length of hospital stay was 1.27±0.5 (1-3) days. In those patients who underwent RIRS, 26 (86.7%) were successfully treated while in 4 of 30 patients (13.3%) the procedure was not successful. Complications were observed in 10 (33.3%) patients. Clavien-I complications were demonstrated in 6 patients, Clavien III complications were demonstrated in 3 patients. One patient had urosepsis, 2 patients had ureteral laceration, and one patient with Clavien IV complication had perirenal hematoma. Laser lithotripsy therapy with RIRS is a safe and effective treatment for symptomatic calyceal diverticular stones and can be offered as the first-line treatment for calyceal diverticular stones. Calyceal diverticula, Stone disease, Flexible ureterorenoscopy, Holmium laser, RIRS.

Safety and efficacy of retrograde intrarenal surgery in primary and residual renal calculi in children

Minimal invasive approach is the current standard of care in the management of pediatric renal calculi. Current guidelines are clear with extra corporal shock wave lithotripsy (ESWL) and percutaneous nephrolithotomy (PCNL) for stone size less than and greater than 20mm respectively. Although retrograde intrarenal surgery (RIRS) is well established in adults but literature on its role, safety and efficacy in children is sparsely available. To share our experience of RIRS and its outcome in a pediatric population in both primary and residual calculi of size less than 20mm. We retrospectively analysed data of children who underwent RIRS for either primary or residual renal calculi from January 2017 to January 2021. Children less than 5 years underwent passive ureteric dilatation with stenting preoperatively. A7.5 Fr flexible ureteroscope with an access sheath was used in all cases while performing RIRS. All the patients had a stent left in situ at the end of the procedure. Data including stone burden, number of sittings, operative time, stone-free rate (SFR) and grade of post procedural complications were analysed with appropriate statistical methods. A total of 20 patients were included in this study. The median age at presentation was 9 years ranging from 9 months to 18 years. Eight patients (40%) presented with primary renal calculi and underwent RIRS directly while the rest of the 12 (60%) had residual calculi following other procedures like SWL, PCNL before undergoing RIRS. Seven patients (35%) had congenital renal anomalies. The mean stone size and operating time (OR) was 12.6±3.2mm 84.5±7.2min respectively. The post-procedural complications were seen in 4 (20%) patients in the form of Grade-1 modified Clavein classification in 3 and Grade 2 in 1 patient. The 100% stone-free rate was achieved in 80% of the cases after first attempt. In the present series, RIRS was effective in both the types of stones (primary and residual) less than 20mm in size, showing 100% stone free rate with maximum of two attempts. Choosing age based optimised passive ureteric dilation led to injury free access for RIRS. Overall complications remained with in low grades and are comparable to current literature. Limitations of the study include small cohort, retrospective study and the need of three anaesthesia procedures in children under 5 years of age. RIRS is safe and effective in children with a renal stone(s) less than 20mm and it has a high success rate in term of achieving stone free status in both primary and residual calculi.

Comparison of Minimally Invasive Treatment Methods for Urinary Stones: A Retrospective Analysis

Introduction: Nephrolithiasis is one of the health concerns worldwide with the increasing prevalence and recurrence rates and the prevalence is ranging from 7% to 13% in North America, 5-9% in Europe, and 1-5% in Asia. Urinary stones are affecting approximately 12% of the world population of all ages, sex, and race. In this study, we evaluate of efficacy of retrograde intrarenal surgery (RIRS) combined with percutaneous nephrolithotomy (PCNL) in the treatment of kidney stones and compare its results with RIRS and PCNL monotherapy. Methods: We analyzed 144 patients who underwent combined method (12.5%), RIRS (53.4%), and PCNL (36.1%) treatments between 2017 and 2018. The stone-free rates after one session at different treatments were following combined method (94.44%), RIRS (83.78%), and PCNL (78.85%). The mean duration of operation was 58.88±13.12 min in combined method, 55.94±26.50 min in the RIRS, and 67.01±29.39 min in the PCNL group (p<0.0277). Duration of hospitalization, intraoperative blood loss, blood transfusion hematuria and complication in the postoperative period were also evaluated. Results: We found that the combined method had a higher stone-free rate, shorter length of stay. This could partially be explained by the minimal invasiveness, less trauma and high stone-free, which result in the complete evacuation of stones and fast recovery. Notably, most of the large, rigid, and complex stones were treated with the combined method. Although the combined treatment is a safe and effective method, the complication rate was slightly higher.

Vücut kitle endeksi ile retrograd intrarenal cerrahi sonuçları arasındaki ilişki

Objective: Overweight and obesity increased worldwide over four decades. In 2016, nearly 11% of men and 15% of women over 18 years old were obese. Obesity is accepted as a risk factor for renal stones. The relationship between obesity and urolithiasis is complicated. Various complications can occur during perioperative or postoperative follow-up in obese patients. Minimal invasive nature and high efficacy of Retrograde Intrarenal Surgery (RIRS) present itself as a safe and less morbid treatment option. In this study, we aimed to compare the efficacy and safety of RIRS in the treatment of kidney stones in different BMI levels. Material and Methods: Files of 552 patients who underwent RIRS for renal stones between January 2012 and December 2017 were reviewed. We classified patients according to the World Health Organisation classification. These three groups were compared for stone-free rate, complication rate, operative and fluoroscopy times and length of hospital stay. Results: The stone-free rate (SFR) of the study population was 80.8%. It was 81% for Group 1, 83.7% for Group 2 and 77.7% for Group 3. There was no statistically significant difference between the three groups among SFR (p=0.346). Clinical insignificant residual fragments (CIRF) status was also similar among the three groups (p=0.254). Complication rates between the three groups were statistically similar (p=0.416). Conclusion: In this study, we have shown that RIRS is a suitable option for all urolithiasis patients, even for obese individuals. Stone-free rates, length of hospital stay, operation time and complication rates in obese patients are similar with non-obese patients. Keywords: urolithiasis; obesity; laser lithotripsy

Safety and efficacy of retrograde intrarenal surgery in geriatric patients by age groups.

To evaluate the effects of aging on the success rate of retrograde intrarenal surgery (RIRS) and the development of medical and surgical complications by dividing geriatric patients into subgroups based on their chronological age. Data of the patients who underwent RIRS due to kidney stones at our clinic between June 2014 and January 2020 were retrospectively reviewed. Patients were divided into three groups based on age: 65-74years (Group 1), 75-84years (Group 2), and ≥ 85years (Group 3). The comorbid diseases of patients were evaluated using the Charlson Comorbidity Index (CCI), total Cumulative Illness Rating Scale for Geriatrics (CIRS-G) score, and CIRS severity index (CIRS-G SI). RIRS success rates and complications were evaluated based on age groups. A total of 336 patients were included in the study. The mean age of the patients was 72.7 ± 6.59years. Stone-free rate was 81.5% in patients aged > 65years and did not change with age. The modified Clavien-Dindo grade I/II complication rates for surgical complications were similar in all three groups (p = 0.818). In the evaluation of ROC analysis for medical complications, it was observed that the cut-off values were 76.5years, CIRS-G score of 4.5, CCI score of 2.5, and CIRS-SI score of 1.18 (p < 0.001). RIRS is an effective and safe treatment option for kidney and proximal ureteral stones in geriatric patients. Although there is an increase in medical complications post-RIRS with aging, surgical complications and stone-free rates remain unchanged.

Comparative analysis of retrograde intrarenal surgery and modified ultra-mini percutaneous nephrolithotomy in management of lower pole renal stones (1.5\u20133.5\u2009cm)

BackgroundTo compare the safety and efficacy of retrograde intrarenal surgery (RIRS) and modified Ultra-mini percutaneous nephrolithotomy (UMP) in semi-supine combined lithotomy position for the management of 1.5–3.5 cm lower pole renal stones (LPSs).MethodsA total of 63 patients with 1.5–3.5 cm LPSs who underwent RIRS (n = 33) or modified UMP (n = 30) in diameter between January 2017 and January 2019 were analyzed retrospectively. Modified UMP was performed in semi-supine combined lithotomy position and a 9.5/11.5 F ureteral access sheath (UAS) was inserted during the procedure in order to maintain low pelvic pressure and to facilitate the removal of stone fragments. Base-line parameters, stone characteristics, illness condition, operation time, postoperative hemoglobin (Hb) drop, postoperative creatinine (Cr) elevation, length of hospital stay, length of postoperative hospital stay, stone-free rate (SFR) and complications were compared between the two groups.ResultsThere were no significant differences between the two groups in base-line parameters, stone characteristics and illness condition. The mean operating time of RIRS group was longer than UMP group (95.61 ± 21.9 vs. 55.0 ± 16.1 min, p < 0.001). The mean postoperative Hb drop was less in RIRS group (7.42 ± 4.7 vs. 15.70 ± 9.8 g/L, p < 0.001). The length of hospital stay and postoperative hospital stay for RIRS were shorter than UMP (4.76 ± 1.1 vs. 5.83 ± 0.8 d, p < 0.001, 2.97 ± 0.9 vs. 4.07 ± 0.9 d, p < 0.001). The Early SFR was higher in UMP group (54.5 vs. 80.0%, p < 0.050) while SFR at 1-month and 3-months postoperatively was similar in both groups (p = 0.504, p = 0.675). There were no significant differences between the two groups in complications (p = 0.228).ConclusionFor patients with 1.5–3.5 cm LPSs, both modified UMP and RIRS are safe and viable. The modified UMP technique was used in this study, application semi-supine combined lithotomy position and the retention of UAS can improve the surgical efficiency and maintain low pressure perfusion in the kidney, which resulted in superior treatment efficacy. Therefore, we highly recommend this technique for LPSs with heavy stone burdens.

Comparative Study between Retrograde Intrarenal Surgery and Percutaneous Nephrolithotomy for the Treatment of Renal Stones

Background: The prevalence of urolithiasis has increased during the last decades and now affects approximately 9% of the adult population specially in developed countries. European Urology Guidelines recommend PCNL in stones larger than 2 cm in size and ESWL in stones smaller than 2 cm in size as the first treatment option. With advances in technology, new generation flexible ureteroscopes with safe and effective lithotripters such as holmium laser have been developed and RIRS became an important alternative in the treatment of large urinary stones.&#x0D; Objective: To evaluate the safety and efficacy of retrograde intrarenal surgery (RIRS) in the treatment of kidney stones and to compare its results with those of percutaneous nephrolithotomy (PCNL).&#x0D; Materials and Methods: We retrospectively analyzed a total of 50 patients ─ 27 patients (20 males and 7 females) who underwent PCNL and 23 patients (17 males and 6 females) who underwent RIRS between January 2015 and December 2017.&#x0D; Results: The mean duration of operation was 60.65 ± 23.56 minutes in the RIRS group and 50.55 ± 12.77 minutes in the PCNL group (p&lt;0.047). The hospital stay was significantly shorter in the RIRS group (2.21 ± 0.9 vs 5.29 ± 1.53 days in the RIRS and PCNL groups, respectively; p&lt;0.016). Stone-free rates after one session were 88.6% and 84.8% in the RIRS and PCNL groups respectively. Blood transfusions were required in five patients in the PCNL group. Complication rates were higher in the PCNL group.&#x0D; Conclusion: This study reveals that RIRS can be an alternative to PCNL in the treatment of kidney stone.&#x0D; J Enam Med Col 2019; 9(2): 84-89

RIRS (Retrograde Intrarenal Surgery) is safe and effective in aging male patients: A single surgeon experience

Aim: Kidney stones are one of the most common diseases around the world. Used together with Extracorporeal Shockwave Lithotripsy (ESWL), Retrograde Intrarenal Surgery (RIRS) is the most common method used for kidney stones below 2 cm. The purpose of our study is to evaluate the safety and efficacy of RIRS in aging male patients with kidney stones.Material and Methods: Our study contains 213 patients who underwent RIRS in Beylikduzu State Hospital between March 2017 and March 2019. Patients were examined retrospectively and divided in four groups according to their age [(between 40 and 49 for Group 1), (between 50 and 59 for Group 2), (between 60 and 69 for Group3), (70 and above for Group 4)]. Demographic data, stone size and location, and American Society of Anesthesiologist (ASA) scores of patients have been recorded. Stone-free rate at postoperative month 3, hospitalization period, double J (DJ) stenting period, ESWL, or whether they have had a second operation have been recorded. ANOVA, Chi-Square tests were used in statistical analysis.Results: Stone characteristics and demographic data of four groups have been examined. Stone size was similar. ASA scores increased with increasing age as expected (p=0.001). Patients had similar mean operation period, hospitalization period and DJ stenting duration, and no statistically significant difference was detected (p>0.05). Upon examining stone-free rate at postoperative month 3, still no statistically significant difference was determined (p>0.05). There was no need for perioperative blood transfusion. Conclusion: These results show that RIRS is an efficient and safe method in elderly male patients with kidney stones. Well-designed studies with large scales are required for the confirmation of this study.

28] Retrograde intra-renal surgery as a treatment modality for unilateral renal calyceal stones of 1–2 cm

ObjectiveTo evaluate the safety and efficacy of retrograde intrarenal surgery (RIRS) as a treatment modality for renal calyceal stones measuring 1–2 cm.

Safety and efficacy of retrograde intrarenal surgery for the treatment of renal stone in solitary kidney patients

Purpose: We present our experience of retrograde intrarenal surgery (RIRS) for the treatment of renal stones in patients with solitary kidneys and evaluate the safety and efficacy of this treatment modality. Materials and methods: Between March 2011 and July 2015, the clinical records of 60 patients with renal stones in solitary kidneys who underwent RIRS were retrospectively reviewed. Demographic characteristics, preoperative urinary culture, blood biochemistry, stone location, and surface area were documented. The final stone-free rates (SFRs) were assessed one month after the last treatment session by computed tomography (CT). Preoperative, operative, and postoperative parameters were analyzed. Serum creatinine (Scr) and glomerular filtration rate (GFR) were measured preoperatively, one month postoperatively, and at each follow-up visit. Results: The mean stone burden was 628 ± 27.2 mm2 (range 301–1199). The mean operative time was 84.4 ± 21.3 min (range 40–115). The mean drop in postoperative hemoglobin was 0.6 ± 0.21 g/dL (range 0.1–0.7). Twelve patients (20%) required second-stage RIRS for residual stones. The SFRs after the single and second procedures were 80% and 95%, respectively. The mean preoperative Scr level was 111.6 ± 45.59 μmol/L, and the mean postoperative Scr level was 96.7 ± 34.12 μmol/L. The change was statistically significant (p = .008). The same findings were observed for GFR. The mean preoperative GFR was 65.04 ± 25.37 ml/min, and the mean postoperative GFR was 76.89 ± 27.2 ml/min (p = .023). Minor complications occurred in nine patients (15%). One patient experienced septic shock and acute renal failure due to steinstrasse. This patient required hemodialysis and percutaneous nephrostomy drainage. One patient developed perirenal abscess and was treated with percutaneous drainage. Conclusion: RIRS is a safe and effective procedure for the treatment of renal stones in patients with solitary kidneys. RIRS did not adversely affect renal function at either the short-term or the long-term follow-up.

Comparison of minimally invasive percutaneous nephrolithotomy and flexible ureteroscopy for the management of ≥1.5 cm renal stones in children

Objective To evaluate the safety and efficacy of retrograde intrarenal surgery(RIRS)and minimally invasive percutaneous nephrolithotripsy (MPCNL)for the pediatric renal calculi (≥1.5 cm). Methods In the retrospective study, 97 patients with renal calculi(≥1.5 cm) underwent operation which is conducted by the same operative team from March 2011 to March 2016 .Among them, 40 patients were treated with RIRS, including 29 male and 11 female patients. 57 patients were treated with minimally invasive percutaneous nephrolithotripsy, including 45 males and 12 female patients. The mean stone size was (1.9±0.4)cm (ranging 1.5-3.0 cm) in the RIRS group and (2.1±0.5)cm(ranging 1.5-3.5 cm) in the MPCNL group. In RIRS group, 3 stones were stag-horn calculi. The diameter in 44 stones was more than 1.5 cm. Among them, 33 stones located in the renal pelvis and upper middle calyces. 11 stones located in the lower calyces. Multiple stones were found in 30 cases and single stone was found in 10 cases. 7 cases had the history of unilateral urolithiasis. 3 cases had the positive results of urine culture before operation. In MPCNL group, 7 stones were stag-horn calculi. The diameter in 60 stones was more than 1.5 cm. Among them, 56 stones located in the renal pelvis and upper middle calyces. 4 stones located in the lower calyces. Multiple stones were found in 41 cases and single stone was found in 16 cases. 4 cases had the history of unilateral urolithiasis. 2 cases had the positive results of urine culture before operation. The mean stone size in MPCNL was larger, but the difference was not statistically significant (P>0.05). No statistical significance was found between the two groups in sex, age, preoperative urine, positive culture, patients with renal staghorn calculi, percentage of multiple calculi, stones in lower calyx and operation history of the same side(P>0.05). The urine white blood cells between the two groups were statistically significant (P<0.01), but the urine white blood cells in RIRS before placing double J stent had no significant difference with those in MPCNL. Results In RIRS group, The mean operative time was(90.2±17.8) minutes. The mean hemoglobin deficit was (7.9±7.9)g/L. The complication rate was 7.5%(3/40). The postoperative hospital stay was (5.0±2.3)days. The hospitalization cost was (42 994.1±9 747.8)yuan.Stone-free rates after one session was 72.5%(29/40). After second procedure, stone-free rates were up to 90.0%(36/40). In MPCNL group, the mean operative time was (77.8±15.6)min. The mean hemoglobin deficit was (10.0±7.1)g/L. The complication rate was 24.6%(14/57). The postoperative hospital stay was (8.0±2.5)days. The hospitalization cost was(24 626.3±6 324.7)yuan. The stone-free rate after one session was 82.5%(47/57). After second procedure, stone-free rates were up to 94.7%(54/57). In statistics, there was no significant difference in hemoglobin drop, the stone-free rate on one session and the final stone-free rates(P>0.05). But significant difference existed in operative time, complications rate, postoperative hospitalization time and hospitalization cost(P<0.05). Conclusion Both RIRS and MPCNL are feasible, safe and minimally invasive way to treat renal calculi(≥1.5 cm) in pediatric patients.The stone-free rates between the two groups are comparable. RIRS has an advantage in postoperative hospitalization time and postoperative complications. MPCNL takes the advantage of operation time, hospitalization cost and needn't routinely places the double-J ureteral stent. Key words: Flexible ureteroscopy; Percutaneous nephrolithotomy; Renal calculi; Children

Retrograde intrarenal surgery using ureteral access sheaths is a safe and effective treatment for renal stones in children weighing

Surgical treatment of pediatric kidney stones has changed dramatically in recent years because of the miniaturization of surgical instruments and the availability of intracorporeal lithotripters. The retrograde intrarenal surgery (RIRS) technique is nowadays considered an effective and safe procedure but studies in very young children are lacking and use of a ureteral access sheath (UAS) has also been debated. To assess safety and efficacy of RIRS using UAS in children weighing <20kg. Data from 13 children weighing <20kg who underwent RIRS for renal stones were collected. A Double-J stent was positioned 14 days before surgery. Demographics, stone location, stone number and composition, stone-free status (SFS) and complications were evaluated. Descriptive statistics were applied to describe the cohort. Thirteen patients, age 3.91±1.8 years (mean±SD), underwent 16 RIRS. Mean patient weight and stone burden were 14.88±3.81kg (range 10-20kg) and 15.5±3.8mm (median 16mm), respectively. A UAS was used in 15 out of 16 (93.8%) procedures. SFS was achieved in 81.3% of cases after the first procedure and 100% after auxiliary procedures. Postoperative urinary tract infections with fever (Clavien II) were observed in two (12.5%) patients. Hydrocalyx (Clavien IIIb) was noted in one (6.3%) patient. Patients with stones located in the lower polar calices (p=0.024) and with mixed composition (p=0.036) had a greater prevalence of complications than those with calculi of other compositions located in other sites. After a mean follow-up of 22.4 months no cases of ureteral strictures or vesicoureteral reflux were observed (Table). The current findings support previous evidence showing safety and efficacy of RIRS with use of the UAS in pre-stented very young children. In our experience RIRS seems to be an effective and safe option with a stone-free rate of 81.3% and only 1 severe complication (Clavien-Dindo grade IIIb) and no long-term complications. This study is, to date, the first to examine the safety and efficacy of RIRS using UAS for the treatment of intrarenal stones in a selected cohort of pre-school patients weighing <20kg. RIRS using UAS is an effective and safe procedure for treating kidney stones in pre-school patients weighing <20kg without complications at both short and long term follow up. Stones of mixed composition located in the lower polar calices are associated with a greater risk of postoperative complications.

Retrograde Intrarenal Surgery and Percutaneous Nephrolithotomy for the Treatment of Renal Stones Greater Than 2 Cm

Background: Stone size is a key factor in the determination of the success of treatment modalities. Recently, there has been a great advancement in technology for minimally invasive management of urinary stones such as percutaneous nephrolithotomy, ureteroscopy, shockwave lithotripsy, and retrograde internal Surgery. Aim of the Study: to assess and compare the efficacy of retrograde intrarenal surgery (RIRS) in the treatment of kidney stones greater than 2 cm versus percutaneous nephrolithotomy (PCNL). Patients and methods: A retrospective analysis was carried out for a total of 118 patients, of which 46 patients underwent RIRS while 72 patients underwent PCNL between May 2013 and May 2017. Results: The mean duration of operation was 96.39±41.11 min in the RIRS group and 69.51±19.3 min in the PCNL group (p<0.001). Hospital stay was significantly shorter in the RIRS group (1.32±0.6 vs. 4.19±1.9 days) in the RIRS and PCNL groups respectively (p<0.001). Stone-free rates after one session were 67.4% and 90.3% of the RIRS and PCNL groups, respectively. Blood transfusions were required in two patients in the PCNL group. Complication rates were generally higher in the PCNL group. Conclusion: The present study concluded that RIRS can be a successful substitute to PCNL in the treatment of kidney stones with a diameter of 2–4 cm particularly in patients with comorbidities.

Retrograde intrarenal surgery vs mini percutaneous nephrolithotripsy for lower pole stones less than 2cm

Aim: To assess the efficacy of retrograde intrarenal surgery (RIRS) in lower pole stones less than 2cm as compared to mini percutaneous nephrolithotomy (mPCNL) Materials and Methods: Between Jan 2013 and April 2016, 172 patients who had renal stones ranging from 7mm to 2 cm in lower pole were alternatively allotted to be treated with RIRS and mPCNL. Stone free status, post operative complications, Operative time and Hospitalisation were analysed in both groups. Stone free rate was defined as residual calculi less than 3mm on ultrasound scan. Results: Both the groups were matched in mean age, sex, stone laterality, stone size. In mPCNL group the stone free status was 93.02% compared to 95.34% in RIRS. Bleeding requiring blood transfusion was observed in 1.16% mPCNL group compared to none in RIRS group. Conclusion: RIRS is safe and comparable to mPCNL in lower pole stones less than 2cm.