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Purpose: To create a machine-learning model for estimating the likelihood of post-retrograde intrarenal surgery (RIRS) sepsis. Methods: All consecutive patients with kidney stone(s) only undergoing RIRS in 16 centers were prospectively included (January 2022–August 2023). Inclusion criteria: adult, renal stone(s) only, CT scan (within three months), mid-stream urine culture (within 10 days). Exclusion criteria: concomitant ureteral stone, bilateral procedures. In case of symptomatic infection/asymptomatic bacteriuria, patients were given six days of antibiotics according to susceptibility profiles. All patients had antibiotics prophylaxis. Variables selected for the model: age, gender, age-adjusted Charlson Comorbidity Index, stone volume, indwelling preoperative bladder catheter, urine culture, single/multiple stones, indwelling preoperative stent/nephrostomy, ureteric access sheath, surgical time. Analysis was conducted using Python programming language, with Pandas library and machine learning models implemented using the Scikit-learn library. Machine learning algorithms tested: Decision Tree, Random Forest, Gradient Boosting. Overall performance was accurately estimated by K-Fold cross-validation with three folds. Results: 1552 patients were included. There were 20 (1.3%) sepsis cases, 16 (1.0%) septic shock cases, and three more cases (0.2%) of sepsis-related deaths. Random Forest model showed the best performance (precision = 1.00; recall = 0.86; F1 score = 0.92; accuracy = 0.92). A web-based interface of the predictive model was built and is available at https://emabal.pythonanywhere.com/ Conclusions: Our model can predict post-RIRS sepsis with high accuracy and might facilitate patient selection for day-surgery procedures and identify patients at higher risk of sepsis who deserve extreme attention for prompt identification and treatment. [ABSTRACT FROM AUTHOR]

To assess outcomes of supracostal ultrasound guided approach percutaneous nephrolithotomy (SUGA-PNL) and retrograde intrarenal surgery (RIRS) in isolated large volume upper calyceal stones (UCS). This was a prospective randomized study including patients with isolated UCS > 20mm. The patients were randomized into two groups: group (P) (SUGA-PNL) and group (R) (RIRS). Patients' demographics, stones characteristics, operative, and postoperative outcomes essentially the stone free rate (SFR) and complications rate were documented. The stone clearance was defined as no fragments or residual fragments less than 2mm in the one month non contrast CT scan follow up. Eighty-nine patients opted to undergo the procedure according to the preoperative randomization. Four patients, 2 patients from each group, lost to follow up and other 2 patients were excluded from group (R) due to a tight ureter. Both groups were comparable as regards the preoperative demographics and stone characteristics. There were statistically significant differences regarding total operative time, the change in hemoglobin level, and postoperative pain score (P: 0.024, 0.010 and 0.032 respectively). The SFR was 88.1% in group (P) compared to 73.2% in group (R) (P: 0.019). Moreover, it did not differ significantly between both groups regarding the intraoperative and postoperative complications. No visceral and thoracic injuries were documented in group (P). On other side, 6 patients (14.6%) from group (R) had different grades of ureteral injury during access sheath placement. SUGA-PNL is a safe and effective treatment modality for UCS > 20mm with a higher SFR than RIRS. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate and compare the clinical results of different single-use flexible ureteroscopes (su-fURS) used in retrograde intrarenal surgery (RIRS). Materials and methods: RIRS cases performed identically by an experienced surgeon between 2022 and 2023 in a single center were retrospectively analyzed. These surgeries were performed with three su-fURS (Redpine RP-U-C12, Hugemed HU30, and Pusen Uscope 3022 A). In the study, the age, gender, body mass index, and Charlson comorbidity index of the patients were compared, along with their clinical details, such as the stone size, volume, density, location, and history of hydronephrosis or a double J stent or SWL. Operation time, stone-free rates (SFR), perioperative and postoperative complications, and hospitalization times were also compared. Results: The study included 208 patients. Pusen had 63 cases, Hugemed had 62, and Redpine had 83. The comparison of the patient's demographic and clinical properties with stone-related variables was similar between the groups. The SFR was similar between the groups (p = 0.056). Perioperative, postoperative, and total complication rates and the need for a second intervention showed no significant differences among the three groups (p = 0.324, 0.088, 0.061, and 0.052, respectively). Conclusion: In the first study comparing the clinical results of cases in which different su-fURS were used, no difference was observed in surgical outcomes and complications, even though the technical features of these devices were different. Urologists should select su-fURS based on clinical requirements, financial constraints, and personal experiences. [ABSTRACT FROM AUTHOR]

To prospectively investigate the effect of music therapy on patient's anxiety and pain level during retrograde intrarenal surgery under spinal anesthesia. 286 patients aged above 18 years, who underwent Retrograde Intrarenal Surgery (RIRS) under spinal anesthesia for renal or ureteral calculi were evaluated between January 2023 and June 2023 by a prospective, randomized, controlled clinical protocol. Patients were randomized into 2 groups. Group 1 included patients, who listened to music, and Group 2 was comprised of patients, who were not allowed to listen to music. Visual Analog Scale (VAS) results and pain sensation, anxiety level, together with the results of State-Trait Anxiety Inventory (STAI), a self-reported anxiety inventory, were captured. The number of patients, who were randomized to the music group (Group 1) and non-music group (Group 2) was 144 and 142, respectively. Mean heart rate in Group 1 and Group 2 was 60 ± 4.19 and 70 ± 8.36, respectively (p = 0.02), indicative of the fact that mean heart rate was significantly lower in the music group. Heart rate measured post-operatively within the first hour subsequent to the procedure was similar in both groups (p < 0.05). The VAS score was significantly lower in Group 1. STAI score in Group 1 and Group 2 was 45.51 ± 2.968 and 49.16 ± 1.88, respectively. Therefore, there was a statistically significant difference (p < 0.001). Music therapy during the RIRS procedure under spinal anesthesia was associated with a significantly decrease in pain and anxiety scores in patients. [ABSTRACT FROM AUTHOR]

Objective: The Ureteral Access Sheath (UAS) has notable benefits but may fail to traverse the ureter in some cases. Our objective was to develop and validate a dynamic online nomogram for patients with ureteral stones who experienced UAS placement failure during retrograde intrarenal surgery (RIRS). Methods: This study is a retrospective cohort analysis using medical records from the Second Hospital of Tianjin Medical University. We reviewed the records of patients with ureteral stones who underwent RIRS in 2022 to identify risk factors associated with UAS placement failure. Lasso combined logistic regression was utilized to identify independent risk factors associated with unsuccessful UAS placement in individuals with ureteral stones. Subsequently, a nomogram model was developed to predict the likelihood of failed UAS placement in this patient cohort. The model's performance was assessed through Receiver Operating Characteristic Curve (ROC) analysis, calibration curve assessment, and Decision Curve Analysis (DCA). Results: Significant independent risk factors for unsuccessful UAS placement in patients with ureteral stones included age (OR = 0.95, P < 0.001), male gender (OR = 2.15, P = 0.017), body mass index (BMI) (OR = 1.12, P < 0.001), history of stone evacuation (OR = 0.35, P = 0.014), and ureteral stone diameter (OR = 0.23, P < 0.001). A nomogram was constructed based on these variables. Model validation demonstrated an area under the ROC curve of 0.789, indicating good discrimination. The calibration curve exhibited strong agreement, and the decision curve analysis revealed a favorable net clinical benefit for the model. Conclusions: Young age, male sex, high BMI, no history of stone evacuation, and small diameter of ureteral stones were independent risk factors for failure of UAS placement in patients with ureteral stones, and the dynamic nomogram established with these 5 factors was clinically effective in predicting the outcome of UAS placement. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to investigate the results and safety of retrograde intrarenal surgery (RIRS) in patients who have previously undergone percutaneous nephrolithotomy (PCNL). Methods: A retrospective analysis included patients who underwent RIRS for kidney stones between August 2018 and April 2023. Group 1 comprised 396 patients who underwent primary RIRS, while Group 2 included 231 individuals who had RIRS after previous PCNL. Evaluation parameters included preoperative characteristics, stone attributes, operative details, treatment outcomes, stone-free status, and complications. Statistical analysis utilized Student's t test, Mann–Whitney U test, and Pearson Chi-square test (p < 0.05). Results: The mean age, body mass index, stone number, mean stone burden, and SFS were not statistically different between the groups. Lower pole stones were identified in 144 patients in Group 1 and 88 patients in Group 2 (p = 0.315). In Group 1 and Group 2, the mean operation time and fluoroscopy time were 65.23 ± 18.1 min, 81.32 ± 14.3 min, 26.34 ± 8.31 s, 46.61 ± 7.6 s, respectively, showing statistically significant differences between the groups (p = 0.013, p < 0.001, respectively). Infundibulum stenosis was identified and treated with a laser in 12% of Group 2 cases. Complications occurred in 12 patients in Group 1 and 14 patients in Group 2 (p = 0.136). Conclusion: A history of PCNL may contribute to extended operation times and increased fluoroscopy exposure in subsequent RIRS without significantly affecting postoperative SFS or complication rates. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to evaluate the clinical efficacy of using a tip‑flexible suctioning ureteral access sheath (TFS-UAS) in combination with a traditional ureteral access sheath (T-UAS) and a disposable flexible ureteroscope (DFU) for treating large renal stones (2–4 cm in diameter). Methods: We retrospectively collected clinical data from 238 patients who underwent retrograde intrarenal surgery (RIRS) at Ganzhou People's Hospital between January 2019 and October 2023. The study included 238 patients who met the inclusion criteria, with 125 in the observation group using TFS-UAS and 113 in the control group using T-UAS. We compared differences in the stone-free rate (SFR), complication rates, surgery duration, and average hospital stay between the two groups. Results: All 238 surgeries were successfully completed. The stone-free rates for the observation group at the first and thirtieth day post-surgery were 87.20% and 95.20%, respectively, whereas for the control group, the rates were 73.45% and 85.84%, showing statistically significant differences (P < 0.05). The overall complication rates were 1.6% for the observation group and 14.16% for the control group, also statistically significant (P < 0.001). The surgical times for stone removal were (101.17 ± 25.64) minutes for the observation group and (86.23 ± 20.35) minutes for the control group, with significant differences (P < 0.05). Conclusion: Compared to T-UAS, combining TFS-UAS with DFU for treating renal stones of 2–4 cm diameter, although more time-consuming, resulted in higher SFRs and improved safety. [ABSTRACT FROM AUTHOR]

Introduction: While the efficacy of flexible ureterorenoscopy (URS) in managing solitary kidney stones (KSs) is widely acknowledged, its effectiveness in treating multiple stones has scarcely been investigated. This study aims to assess the effectiveness and safety of retrograde intrarenal surgery (RIRS) utilizing flexible URS and laser lithotripsy in the management of multiple KSs. Methods: This study was a single-group cohort study conducted on patients with multiple KSs who underwent treatment with RIRS using flexible URS and laser lithotripsy. Stone-free status was considered as the lack of residual stone fragments or any residual stone of any size. The first follow-up appointment was arranged 3-4 weeks following the procedure. If significant residual stones were present, patients underwent reintervention within 2-4 weeks. Results: A total of 110 patients with multiple KSs were included. The mean stone burden was 27.5 ± 7.9 mm, and the mean duration of the operation was 54.9 ± 19.7 minutes. Seven cases (6.3%) experienced intraoperative complications, while postoperative complications were found in eight cases (7.3%). After four weeks, a stone-free rate (SFR) was documented in 80.9% of the cases, and this rate increased to 93.6% after three months. The SFR after three months was significant with Guy's stone score (p < 0.001); however, it did not reach a significant level with any other parameters. Conclusions: The RIRS with flexible URS may be an effective and potentially safe procedure for treating multiple KSs. It may yield a favorable SFR with an acceptable complication rate. [ABSTRACT FROM AUTHOR]

Background and Objectives: Retrograde intrarenal surgery (RIRS) is a minimally invasive technique for nephrolithiasis. RIRS is performed via a monitor screen displaying a magnified surgical site. Respiration can affect the stability of the surgical view during RIRS because the kidneys are close to the diaphragm. The purpose of this trial is to compare the effect of anesthesia type on the stability of the surgical view during RIRS between spinal anesthesia and general anesthesia. Materials and Methods: Patients were allocated to the general anesthesia group or spinal anesthesia group. During surgery, movement of the surgical field displayed on the monitor screen was graded by the first assistant on a 10-grade numeric rating scale (0–10). Next, it was also graded by the main surgeon. After surgery, we evaluated the discomfort with the anesthesia method for all patients. Results: Thirty-four patients were allocated to the general anesthesia group and 32 patients to the spinal anesthesia group. The average values of the two surgeons for surgical field oscillation grade showed vision on the monitor screen was more stable in the general anesthesia group than the spinal anesthesia group (3.3 ± 1.6 vs. 5.0 ± 1.6, p < 0.001). The degrees of the inconvenience of the surgery did not differ between the groups (0.7 ± 1.8 vs. 1.6 ± 2.6, p = 0.114), even though more patients reported inconvenience with a grade of 3 or more in the spinal anesthesia group (8.8% vs. 28.1%, p = 0.042). Conclusions: In terms of the visualization of the surgical site, general anesthesia might provide a more stable surgical view during RIRS compared to spinal anesthesia without increasing inconvenience induced by the type of anesthesia. [ABSTRACT FROM AUTHOR]

Purpose: Urolithiasis in infants is uncommon. Percutaneous nephrolithotomy, extracorporeal shockwave lithotripsy, and retrograde intrarenal surgery (RIRS) are the management options. RIRS is the least studied of these options in infants. In our series of 23 cases, we aim to assess the feasibility, efficacy, and safety of RIRS in

Introduction: Retrograde intrarenal surgery (RIRS) is the standard treatment for renal calculi. Direct visualization and fragmentation are its major advantages. The variable stone clearance rates and the ergonomic challenges faced by urologists are a few limitations. Table tilt enhances stone clearance and improves surgical ergonomics by facilitating better access to stones and reducing procedural strain. Subjects and Methods: In this prospective study, patients with intrarenal calculi were randomized into standard lithotomy RIRS (S-RIRS) and table-tilted RIRS (T-RIRS) groups. Specified table tilts were suggested for each of the stone locations. The outcomes with regard to stone clearance, operative and lasing time, and ergonomics were studied. Results: About 100 patients were studied, with 50 in each group. The overall operating time and lasing time in the T-RIRS group were less than that in the S-RIRS group (P < 0.001). The complication rates were the same in both groups. Most surgeons felt that the surgical ergonomics was better in the T-RIRS group (P < 0.001). When stone-free status was analyzed, seven patients in the S-RIRS group and one in the T-RIRS group had residual stones. The mean Borg category-ratio 10 (CR-10) scores in the S-RIRS and T-RIRS groups were 4.18 and 2.20, respectively (P < 0.001). Conclusions: This is the first study to document the distinct advantages of T-RIRS and its benefits on surgical ergonomics. T-RIRS resulted in significantly shorter operative and lasing times, particularly for stones in lower calyces. Surgical ergonomics, assessed by the Borg CR-10 scale, were significantly better in the T-RIRS group. T-RIRS should become a standard of care for patients undergoing RIRS.

Abstract Objective The Ureteral Access Sheath (UAS) has notable benefits but may fail to traverse the ureter in some cases. Our objective was to develop and validate a dynamic online nomogram for patients with ureteral stones who experienced UAS placement failure during retrograde intrarenal surgery (RIRS). Methods This study is a retrospective cohort analysis using medical records from the Second Hospital of Tianjin Medical University. We reviewed the records of patients with ureteral stones who underwent RIRS in 2022 to identify risk factors associated with UAS placement failure. Lasso combined logistic regression was utilized to identify independent risk factors associated with unsuccessful UAS placement in individuals with ureteral stones. Subsequently, a nomogram model was developed to predict the likelihood of failed UAS placement in this patient cohort. The model’s performance was assessed through Receiver Operating Characteristic Curve (ROC) analysis, calibration curve assessment, and Decision Curve Analysis (DCA). Results Significant independent risk factors for unsuccessful UAS placement in patients with ureteral stones included age (OR = 0.95, P

Abstract Our study aimed to retrospectively analyze the patients who underwent the combination of negative pressure equipment and RIRS(NP-RIRS) for renal stones, and identified new high-risk factors related to infection. 456 patients with renal stones ≤ 3 cm underwent NP-RIRS in our department, from January 2022 to October 2023. All patients were divided into non-infection group(NIRIRS group) and infection group(IRIRS group) based on infection complications during the perioperative period. Establish a receiver operating characteristic curve(ROC curve)based on variables with statistical differences, and use the Jordan index to find the optimal cutoff value. Classify the data into two categories based on the best truncation value, and perform binary logistic regression analysis on the classified data. In the IRIRS group, there were 10 cases of fever (2.92%), 2 cases of sepsis (0.58%), and no cases of septic shock or death. The length and the CT value of the stone were 16 (13,21) vs. 22 (19,24) (p

Background: The treatment of lower calyceal calculi with a size

Objectives: 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. Materials and Methods: 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. Results: 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. Conclusions: 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.

Objective: This study aimed to investigate the effects of ureteral access sheath (UAS) use in patients undergoing retrograde intrarenal surgery (RIRS) due to kidney stones on postoperative early kidney injury development using urine kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) measurements. Materials and Methods: Thirty patients using UAS (UAS group) and 30 not using UAS (non-UAS group), for whom RIRS was planned, and 30 healthy controls (control group) were included between January and June. Blood urea nitrogen and creatinine in the blood and KIM-1 and NGAL in the urine at the pre-operative and postoperative 24th hours and KIM-1 and NGAL at the postoperative 4th and 24th hours were studied. The same biomarkers were analyzed once in the control group. During follow-up, KIM-1 and NGAL were measured using the enzyme-linked immunosorbent assay method within 6 months. Results: There was no significant difference between the pre-operative KIM-1 and NGAL values and the postoperative 24-h KIM-1 and NGAL values in the UAS group (p>0.05), whereas there was a significant difference in the non-UAS group (p

Abstract Purpose The aim of this study is to evaluate the outcomes of retrograde intra renal surgery (RIRS) in the setting of large or multiple stones in children (15 mm, or both. Outcomes included stone free rate (SFR) and complications within 30 days. Results In total, 344 patients were included with 197 and 147 in Groups 1 and 2, respectively. Ureteric access sheaths were more frequently used in Group 2 (39.5% vs. 56.8%, p = 0.021). The operation time was significantly longer in Group 2 (p

Objective: To determine surgical outcomes and stone‐free rates (SFRs) when offering upfront retrograde intrarenal surgery (RIRS) to patients with asymptomatic incidental renal stones (AIRS), as active surveillance, shockwave lithotripsy or upfront intervention in patients with AIRS is still a debate among urologists. Patients and Methods: This retrospective FLEXible Ureteroscopy Outcomes Registry (FLEXOR), supported by the Team of Worldwide Endourological Researchers (TOWER), examines adult patients who underwent RIRS. We analysed a subset of asymptomatic patients with renal stones on imaging who were treated with RIRS. Data includes patient characteristics, stone specifications, anaesthesia type, perioperative details, complications, and SFR. A multivariable logistic regression analysis was performed to assess factors associated with the SFR. Results: Among 679 patients with AIRS, 640 met the inclusion criteria. The median age was 55 years, with 33.4% being female. In all, 22.1% had positive urine cultures. The median stone diameter was 12 mm, commonly in lower and interpolar locations. RIRS was preferentially performed under general anaesthesia using a reusable scope in 443 cases. Prophylactic antibiotics were administered to 314 patients. The median operation time was 58 min and the median laser time was 24 min. The SFR was 68.8%. The use of holmium laser (odds ratio [OR] 0.21, 95% confidence interval [CI] 0.06–0.63; P < 0.01) and multiple stones (OR 0.38, 95% CI 0.19–0.76; P < 0.01) were factors associated with lower odds of being stone free. Overall complications were minimal, with sepsis in 1.6% of patients. Re‐interventions were performed in 76 cases (11.8%), with RIRS being the most common in 67 cases (10.6%). Conclusion: Our multicentre real‐world study is the first of its kind that highlights the pros and cons of offering RIRS to patients with AIRS and demonstrates a favourable SFR with acceptable complications. Pre‐emptively discussing potential re‐intervention helps patients make informed decisions, particularly in cases involving large and multiple stones. [ABSTRACT FROM AUTHOR]

Background: Complete removal of renal stones is crucial for optimal patient outcomes, but recent studies have reported residual stones after retrograde intrarenal surgery (RIRS). This study aimed to identify the associated risk factors to improve patient management and treatment selection. Methods: This cohort study was conducted over 18 months at two hospitals and recruited adult patients with renal stones less than 3 cm. Preoperative assessment included medical history, physical examination, laboratory tests, and radiological imaging. Intraoperative and postoperative data collection and follow-up were conducted to evaluate surgical success and potential complications. Results: A total of 100 patients were included, with a mean age of 45.3 ± 10.7 years and a mean BMI of 26.2 ± 1.4 kg/m2. Approximately 19% of the patients had residual stones after the RIRS procedure. The RUSS score showed good diagnostic performance with an AUC of 0.843, and the optimal cut point was ⩾2.0 with a sensitivity of 52.6% and specificity of 95.1%. Independent predictors of residual stones were multiple sites (OR = 24.98; p = 0.002), multiple stones (OR = 13.62, p = 0.002), stone size of 21–30 mm (OR = 4.91, p = 0.038), lower calyx site (OR = 4.85, p = 0.033), and surgeon experience of fewer than 50 cases (OR = 6.82, p = 0.020), Conclusions: This study identifies several factors associated with residual stones after RIRS for renal stones, including stone size, location, number, and surgeon experience. The study suggests that the RUSS score can be used as a reliable tool for predicting the likelihood of residual stones, which can help clinicians in patient selection and treatment planning. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to compare the results of retrograde intrarenal surgery (RIRS) and mini-percutaneous nephrolithotomy (mini-PCNL) for the treatment of 1–2 cm kidney stones in pediatric patients. Methods: The records of patients under the age of 18 years who were diagnosed with unilateral 1–2 cm kidney stones for the first time and underwent endoscopic surgery between February 2008 and April 2022 were retrospectively examined. The patients were divided into two groups: mini-PCNL and RIRS surgery. Parameters such as age, gender, number of stones, side, size and localization were examined. The main endpoint of the study was to compare stone-free rates (SFR) one month after both surgeries. Surgery and fluoroscopy times, postoperative hospital stay, hemoglobin decrease and complication rates were compared between the groups. SFR was evaluated one month after surgery by direct urinary system radiography and USG or CT. Results: A total of 58 patients were included in the study. There were 35 patients in the mini-PCNL group and 23 patients in the RIRS group. Table 1 shows the demographic and clinical characteristics of both groups. There was no significant difference between the groups in terms of age, gender, stone size, location, side and density. Calcium oxalate stones were observed at a higher rate in both groups. Mean fluoroscopy time was higher in the mini-PCNL group (p = 0.001). The mean surgery time was lower in the mini-PCNL group (p = 0.024). The mean hemoglobin decrease was greater in the percutaneous group (p = 0.039). There were no differences between the groups in terms of postoperative hospital stay, complication rates, and SFR one month after surgery. Conclusion: Although mini-PCNL seems to be more advantageous in terms of operation time compared to RIRS, it is disadvantageous in terms of average fluoroscopy time, radiation received and average hemoglobin decrease. [ABSTRACT FROM AUTHOR]

Objectives: 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. Materials and Methods: 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. Results: 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. Conclusions: 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. [ABSTRACT FROM AUTHOR]

Background: The treatment of lower calyceal calculi with a size <1.5 cm remains a subject of debate. Mini-percutaneous nephrolithotomy (Mini PCNL) and retrograde intrarenal surgery (RIRS) are both effective options, but there is a need for comparative analysis to determine the optimal approach. Mini-perc has the advantage of direct visualization and efficient fragmentation and clearance, while RIRS is a minimally invasive technique with excellent visualization and minimal morbidity. Aims and Objectives: This study aims to evaluate and compare the efficacy, safety, and outcomes of mini-perc PCNL and RIRS in the management of lower calyceal calculi. Materials and Methods: This retrospective comparative cohort study included a total of 72 patients with lower calyceal calculi <1.5 cm. Thirty-six patients underwent mini-perc, and 36 patients underwent RIRS. Results: No significant differences were observed in patient demographic characteristics, stone size, or stone location between the mini-perc and RIRS groups. The mini-perc group had a significantly higher stone-free rate (SFR) (94.4%) compared to the RIRS group (86.1%) (P<0.05). The mini-perc technique had a higher success rate in first-session stone clearance (88.9%) compared to RIRS (77.8%) (P<0.05). The mini-perc group had a longer operative time, higher estimated blood loss, and a longer post-operative hospital stay compared to the RIRS group (P<0.05). Conclusion: Both mini-perc and RIRS techniques are effective for managing lower calyceal calculi <1.5 cm. Mini-perc offers a SFR and a better success rate in first-session stone clearance compared to RIRS. However, mini-perc procedures are associated with longer operative time, higher estimated blood loss, and a longer post-operative hospital stay. [ABSTRACT FROM AUTHOR]

Background and Objectives: This paper evaluates the efficacy and safety of ureteral access sheath (UAS) utilization in retrograde intrarenal surgery (RIRS). Materials and Methods: We searched PubMed, Embase, and the Cochrane Library up to 30 August 2023. The inclusion criteria comprised English-language original studies on RIRS with or without UAS in humans. The primary outcome was SFR, while the secondary outcomes included intraoperative and postoperative complications, the lengths of the operation and the hospitalization period, and the duration of the fluoroscopy. Subgroup analyses and a sensitivity analysis were performed. Publication bias was assessed using funnel plots and Egger's regression tests. Dichotomous variables were analyzed using odds ratios (ORs) with 95% confidence intervals (CIs), while mean differences (MDs) were employed for continuous variables. Results: We included 22 studies in our analysis. These spanned 2001 to 2023, involving 12,993 patients and 13,293 procedures. No significant difference in SFR was observed between the UAS and non-UAS groups (OR = 0.90, 95% CI 0.63–1.30, p = 0.59). Intraoperative (OR = 1.13, 95% CI 0.75–1.69, p = 0.5) and postoperative complications (OR = 1.29, 95% CI 0.89–1.87, p = 0.18) did not significantly differ between the groups. UAS usage increased operation times (MD = 8.30, 95% CI 2.51–14.10, p = 0.005) and fluoroscopy times (MD = 5.73, 95% CI 4.55–6.90, p < 0.001). No publication bias was detected for any outcome. Conclusions: In RIRS, UAS usage did not significantly affect SFR, complications, or hospitalization time. However, it increased operation time and fluoroscopy time. Routine UAS usage is not supported, and decisions should be patient-specific. Further studies with larger sample sizes and standardized assessments are needed to refine UAS utilization in RIRS. [ABSTRACT FROM AUTHOR]

To identify the radiological parameters which may help to predict the success of ureteral access sheath (UAS) placement during retrograde intrarenal surgery (RIRS).The study included 49 patients in whom failure ureteral access sheath placement in RIRS and 49 control group patients who were successfully placement between January 2023 and December 2023. The age, gender, body mass index (BMI), non-contrast computed tomography (NCCT), and kidney ureter bladder (KUB) radiographs were compared between the two groups. Measurements of the anteroposterior (ap) diameter of the pelvic inlet, anteroposterior diameter of the pelvic outlet, interspinous distance diameter were taken from non-contrast computed tomography (NCCT), while pelvic anteroposterior diameter and pelvic lateral diameter were measured from kidney ureter bladder (KUB) radiography. There were no significant differences between the groups in age, gender, body mass index, ap pelvic inlet diameter, ap pelvic outlet, and interspinous distance diameter. However, a statistically significant difference was found between the pelvic ap diameter and pelvic lateral diameter values measured on the KUB radiography. The values for pelvic ap diameter and pelvic lateral diameter measured in the KUB radiographs can be used to predict the likelihood of UAS passage during RIRC procedures. However, further studies with larger patient groups are needed to establish a cut-off value. [ABSTRACT FROM AUTHOR]

Ho: YAG laser lithotripsy is widely used for urinary stone treatment, but concerns persist regarding its thermal effects on renal tissues. This study aimed to monitor intrarenal temperature changes during kidney stone treatment using retrograde intrarenal surgery with Ho: YAG laser. Fifteen patients were enrolled. Various laser power settings (0.8 J/10 Hz, 1.2 J/12 Hz) and irrigation modes (10 cc/min, 15 cc/min, 20 cc/min, gravity irrigation, and manual pump irrigation) were used. A sterile thermal probe was attached to a flexible ureterorenoscope and delivered into the calyceal system via the ureteral access sheath. Temperature changes were recorded with a T-type thermal probe with ± 0.1 °C accuracy. Laser power significantly influenced mean temperature, with a 4.981 °C difference between 14 W and 8 W laser power (p < 0.001). The mean temperature was 2.075 °C higher with gravity irrigation and 2.828 °C lower with manual pump irrigation (p = 0.038 and p = 0.005, respectively). Body mass index, laser power, irrigation model, and operator duty cycle explained 49.5% of mean temperature variability (Adj. R2 = 0.495). Laser power and operator duty cycle positively impacted mean temperature, while body mass index and specific irrigation models affected it negatively. Laser power and irrigation rate are critical for intrarenal temperature during Ho: YAG laser lithotripsy. Optimal settings and irrigation strategies are vital for minimizing thermal injury risk. This study underscores the need for ongoing research to understand and mitigate thermal effects during laser lithotripsy. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to compare the efficacy and safety of Ultra-mini-percutaneous nephrolithotomy (UMP) and Retrograde intrarenal surgery (RIRS) for renal/upper ureteral calculi in 1.0–2.0 cm diameter. Methods: From October 2017 to October 2022, the surgical treatment of patients with renal/upper ureteral calculi in 1.0–2.0 cm diameter who were admitted to our hospital was retrospectively analyzed. They were divided into two groups, the UMP group (sixty-two cases) and the RIRS group (one hundred and nine cases), according to the different surgical methods. Baseline data includes general information, stone size, location, CT value, hydronephrosis, creatinine level, etc. Results: Intraoperative blood loss was 33.6 ± 8.5 ml in the UMP group was significantly more than 4.3 ± 0.7 ml in the RIRS group (P < 0.05). Intraoperative renal pelvis pressure of UMP group 10.5 ± 1.3 mmHg was significantly lower than RIRS group 23.6 ± 5.6 mmHg (P < 0.05). The incidence of postoperative infection was higher in the RIRS group (thirteen cases [11.93%]), and one case ([1.61%]) in the UMP group (P < 0.05). Routine CT scans on the second day and two months after surgery showed that the stone clearance rates in the UMP group were 87.1% and 93.5%, respectively, higher than those in the RIRS group (69.7% and 79.8%, respectively; P < 0.05). Conclusion: UMP has the advantage of a higher stone-free rate but a higher risk of injury and bleeding. The advantages of RIRS include less trauma, less bleeding, and faster recovery, but lower stone-free rates and a higher risk of infection. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the effects of ureteral access sheath (UAS) use in patients undergoing retrograde intrarenal surgery (RIRS) due to kidney stones on postoperative early kidney injury development using urine kidney injury molecule-1 (KIM-1) and neutrophil gelatinaseassociated lipocalin (NGAL) measurements. Materials and Methods: Thirty patients using UAS (UAS group) and 30 not using UAS (non-UAS group), for whom RIRS was planned, and 30 healthy controls (control group) were included between January and June. Blood urea nitrogen and creatinine in the blood and KIM-1 and NGAL in the urine at the pre-operative and postoperative 24th hours and KIM-1 and NGAL at the postoperative 4th and 24th hours were studied. The same biomarkers were analyzed once in the control group. During follow-up, KIM-1 and NGAL were measured using the enzyme-linked immunosorbent assay method within 6 months. Results: There was no significant difference between the pre-operative KIM-1 and NGAL values and the postoperative 24-h KIM-1 and NGAL values in the UAS group (p>0.05), whereas there was a significant difference in the non-UAS group (p<0.05). The postoperative 24-h KIM-1 and NGAL values were significantly higher in the UAS group than in the non-UAS group (p<0.05). Conclusion: It was determined that more kidney injury developed in the non-UAS group UAS than in the UAS group, especially at the postoperative 24th hour. The use of UAS in RIRS is effective in preventing the development of potential kidney injury. [ABSTRACT FROM AUTHOR]

Introduction: Retrograde intrarenal surgery (RIRS) is associated with complications, many of which are related to the intrarenal pressure (IRP). We aim to describe the design of a novel isoprenaline-eluting guidewire ("IsoWire") and present the results from the first in vitro release studies and the first animal studies showing its effect on IRP. Materials and Methods: The IsoWire comprises a Nitinol core surrounded by a stainless-steel wire wound into a tight coil. The grooves created by this coil provided a reservoir for adding a hydrogel coating into which isoprenaline, a beta-agonist, was loaded. Animal studies were performed using a porcine model. For the control, IRP, heart rate (HR), and mean arterial pressure (MAP) were measured continuously for 6 minutes with a standard guidewire in place. For the experiment, the standard hydrophilic guidewire was removed, the IsoWire was inserted into the renal pelvis, and the same parameters were measured. Results:In vitro analysis of the isoprenaline release profile showed that most (63.9 ± 5.9%) of the loaded drug mass was released in the 1st minute, and almost all of the drug was released in the first 4 minutes exponentially. Porcine studies showed a 25.1% reduction in IRP in the IsoWire that released 10 μg in the 1st minute; however, there was a marked increase in HR. The average percentage reduction in IRP was 8.95% and 21.3% in the IsoWire that released 5 and 7.5 μg of isoprenaline, respectively, with no changes in HR or MAP. Conclusions: The IsoWire, which releases 5 and 7.5 μg of isoprenaline in the 1st minute, appears to be safe and effective in reducing the IRP. Further studies are needed to establish whether the isoprenaline-induced ureteral relaxation will render easier insertion of a ureteral access sheath, reduce IRP during sheathless RIRS, or even promote the practice of sheathless RIRS. [ABSTRACT FROM AUTHOR]

Using thulium fiber laser rather than holmium:yttrium aluminum garnet laser may achieve higher stone-free rates in stones located in the kidney but not in the ureter. Thulium fiber laser (TFL) emerged as a competitor of holmium:yttrium aluminum garnet (Ho:YAG) laser for the treatment of urinary stones. To compare the efficacy between Ho:YAG and TFL for laser lithotripsy of renal and ureteral stones. A literature search was conducted using PubMed/Medline, Embase, and Web of Science databases to identify reports published until May 2023. The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed to identify eligible studies. The primary outcome was to compare the stone-free rate (SFR) between Ho:YAG and TFL for laser lithotripsy. Eleven studies met our inclusion criteria, and data from 1286 and 880 patients who underwent, respectively, Ho:YAG and TFL laser lithotripsy were reviewed. Most studies included ureteroscopy (URS) and retrograde intrarenal surgeries as procedures, two included percutaneous nephrolithotomy, and one included URS exclusively. Only two studies reported results in pediatric patients. TFL was associated with a higher SFR (odds ratio [OR] 1.84, 95% confidence interval [CI]: 1.06–3.20; p = 0.031) when no residual fragment is considered, but not when SFR refers to the presence of fragments <3 mm (OR 2.48, 95% CI: 0.98–6.29; p = 0.055) or when only Ho:YAG with MOSES is considered (p = 0.068). According to the stones' location, TFL was associated with higher SFRs than Ho:YAG for renal (OR 3.14, 95% CI: 1.69–5.86; p < 0.001) but not for ureteral (p = 0.8) stones. TFL was associated with a lower intraoperative complication rate (OR 0.34, 95% CI: 0.19–0.63; p < 0.001). No difference was found in major (p = 0.4) or overall (p = 0.4) complication rate, operative time (p = 0.051), and laser time (p = 0.9). TFL is a promising laser for the treatment of urinary stones with some advantages over Ho:YAG. Further high-quality studies are needed to confirm these findings and optimize the surgical settings. The use of thulium fiber laser rather than holmium:yttrium aluminum garnet permits to reach a higher stone-free rate in stones located in the kidney rather than in the ureter. [ABSTRACT FROM AUTHOR]

Introduction: While the efficacy of flexible ureterorenoscopy (URS) in managing solitary kidney stones (KSs) is widely acknowledged, its effectiveness in treating multiple stones has scarcely been investigated. This study aims to assess the effectiveness and safety of retrograde intrarenal surgery (RIRS) utilizing flexible URS and laser lithotripsy in the management of multiple KSs. Methods: This study was a single-group cohort study conducted on patients with multiple KSs who underwent treatment with RIRS using flexible URS and laser lithotripsy. Stone-free status was considered as the lack of residual stone fragments or any residual stone of any size. The first follow-up appointment was arranged 3-4 weeks following the procedure. If significant residual stones were present, patients underwent reintervention within 2-4 weeks. Results: A total of 110 patients with multiple KSs were included. The mean stone burden was 27.5 ± 7.9 mm, and the mean duration of the operation was 54.9 ± 19.7 minutes. Seven cases (6.3%) experienced intraoperative complications, while postoperative complications were found in eight cases (7.3%). After four weeks, a stone-free rate (SFR) was documented in 80.9% of the cases, and this rate increased to 93.6% after three months. The SFR after three months was significant with Guy’s stone score (p < 0.001); however, it did not reach a significant level with any other parameters. Conclusions: The RIRS with flexible URS may be an effective and potentially safe procedure for treating multiple KSs. It may yield a favorable SFR with an acceptable complication rate.

Abstract Background Flexible ureteroscopy offers numerous advantages, such as increased reach, superior stone-free rate, reduced risk of bleeding, minimal surgical trauma, and faster recovery time. There are few studies discussing the effectiveness of single-use flexible ureteroscopy in children, and none so far have addressed its safety. This study aims to evaluate the effectiveness and safety of a single-use flexible ureteroscope for treating upper urinary tract stones in children. Methods This study included children with single upper urinary tract stones measuring less than 2 cm who underwent single-use flexible ureteroscopy between October 2020 and January 2023. We assessed the following patient characteristics: age, gender, stone type, size, position, pre and postoperative stent placements, use of a ureteral access sheath, stone-free rate, operation duration, and the rate of complications. A patient was considered stone-free if there were no residual stone particles larger than 3 mm after surgery. Results Flexible ureteroscopy and holmium laser lithotripsy were undertaken for 44 participants, with an average age of 8.5 years (range: 2–16 years). The typical stone size was 14 mm (range: 6–20 mm). The average operation time was 74 min (range 35–110 min). Ureteral access sheaths were used in 81.8% (36 out of 44) of procedures. After a single FURS session, 86.36% (38 out of 44) of patients achieved stone-free status. Postoperative JJ stent application was noted in 86.4% (38 out of 44) of patients. Complications were categorized using the Calvien system, revealing that 25% (11 out of 44) of patients experienced mild hematuria, colic, and low-grade fever (Calvien I). No severe side effects like mucosal avulsion or ureteral perforation were reported. Conclusion In the short-term, single-use flexible ureteroscopy is a safe and effective method for managing single renal and proximal ureteric stones, measuring 2 cm or less, in children.

Introduction. The emergence of new scientific and clinical evidence on the use of retrograde intrarenal surgery (RIRS) for the management of kidney stones has prompted periodic systematisation, analysis, and evaluation of outcomes to standardise its application and determine future directions for research and development.Objective. To present the Russian adaptation of a guideline on retrograde intrarenal surgery from the International Urolithiasis Alliance guideline series to provide a theoretical basis for urologists performing RIRS.Materials & Methods. A systematic review was conducted on the RIRS-associated publications available in the PubMed database to prepare a set of recommendations during the period from 1 January 1964 until 1 October 2021. The recommendations were evaluated using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system, which classifies, evaluates, develops, and examines recommendations. The modified Oxford Centre for Evidence-Based Medicine's (OCEBM) system for categorising the level of evidence and relevant comments have been applied to assess the strength of the conclusions.Results. The research team conducted a comprehensive analysis of 36 published clinical guidelines on the following topics: 1. Indications and Contraindications 2. Preoperative Imaging 3. Preoperative Ureteral Stenting 4. Preoperative Medications 5. Perioperative Use of Antibiotics 6. Use of Antithrombotic Therapy 7. Anesthesia Issues 8. Intraoperative Positioning 9. Equipment 10. Complications.Conclusion. A series of recommendations for RIRS, offered here should help provide safe and effective performance of RIRS.

Objective: This narrative review aims to describe measures to minimise the risk of complications during percutaneous nephrolithotomy (PCNL), ureteroscopy, and retrograde intrarenal surgery. Methods: A literature search was conducted from the PubMed/PMC database for papers published within the last 10 years (January 2012 to December 2022). Search terms included “ureteroscopy”, “retrograde intrarenal surgery”, “PCNL”, “percutaneous nephrolithotomy”, “complications”, “sepsis”, “infection”, “bleed”, “haemorrhage”, and “hemorrhage”. Key papers were identified and included meta-analyses, systematic reviews, guidelines, and primary research. The references of these papers were searched to identify any further relevant papers not included above. Results: The evidence is assimilated with the opinions of the authors to provide recommendations. Best practice pathways for patient care in the pre-operative, intra-operative, and post-operative periods are described, including the identification and management of residual stones. Key complications (sepsis and stent issues) that are relevant for any endourological procedure are then be discussed. Operation-specific considerations are then explored. Key measures for PCNL include optimising access to minimise the chance of bleeding or visceral injury. The role of endoscopic combined intrarenal surgery in this regard is discussed. Key measures for ureteroscopy and retrograde intrarenal surgery include planning and technique to minimise the risk of ureteric injury. The role of anaesthetic assessment is discussed. The importance of specific comorbidities on each step of the pathway is highlighted as examples. Conclusion: This review demonstrates that the principles of meticulous planning, interdisciplinary teamworking, and good operative technique can minimise the risk of complications in endourology.

Infectious complications are among the most common and potentially life-threatening morbidities of retrograde intrarenal surgery (RIRS). Few predictive tools on these complications include radiological signs. The Mayo adhesive probability (MAP) score is an image-based scoring system that incorporates two radiological signs: perinephric fat stranding and perinephric fat thickness. Previous studies have suggested an association between these signs and febrile urinary tract infection (UTI) following lithotripsy. This study aimed to evaluate the predictive factors, including the MAP score, for post-RIRS fever and sepsis. A total of 260 patients who underwent 306 RIRS between October 2019 to December 2023 due to renal or upper ureteral stones were included in this retrospective study. Patient demographics, perioperative characteristics, stone factors, radiological signs, and MAP scores were recorded. Multivariate logistic regression analysis was used to evaluate the risk factors associated with postoperative fever and sepsis. Postoperative fever and sepsis occurred in 20.8% and 8.5% of the patients, respectively. On multivariate analysis, female gender, history of recurrent UTI, larger maximal stone diameter, and higher MAP score were independent risk factors for postoperative fever and sepsis. Identifying the risk factors for post-RIRS infectious complications is imperative to providing the proper perioperative management. The MAP score is a promising, easily calculated, image-based scoring system that predicts post-RIRS fever and sepsis. [ABSTRACT FROM AUTHOR]

Purpose: To define a peak force of insertion (PFOI) threshold for ureteral damage during ureteral access sheath (UAS) placement on an experimental ureteral orifice model. Methods: A specially designed water tank using 2 laparoscopic 5 mm ports and 2 different size (10 Fr and 8 Fr) sealing cap adaptors (SCA) as ureteral orifices was used to perform the test. A 10–12 Fr UAS was fixed to a load cell and the force of insertion (FOI) was continuously recorded with a digital force gauge.13 experts in the field of endourology who participated performed 3 UAS insertions. The FOI was recorded initially with 10 Fr followed by 8 Fr SCA. On the final insertion, the orifice was obstructed, leaving a 5 cm length to insert the UAS. The experts were asked to "Stop at the point they anticipate ureteral damage, and they would not proceed in real life". Results: Using 10 Fr SCA the PFOI was 2.12 ± 0.58 Newton (N) (range:1.48–3.48) while 8 Fr SCA showed a PFOI 5.76 ± 0.96 N (range:4.05–7.35). Six of the experts, said they would stop proceeding when they reached above 5.1 N. Three experts had PFOI < 5.1 N and the other 4 stated they would go with PFOIs of 5.88, 6.16, 6.69 and 7.35 N when using SCA of 8 Fr.The highest load they would stop proceeding had a PFOI of 6.09 ± 1.87 N (range: 2.53–10.74). Conclusion: The PFOI threshold for ureteral damage inserting UAS of the experts is variable. Although FOI is a subjective perception, experience suggests that ureteral injury may occur at an average of 6.05 N perceived by surgeons' tactile feedback. In-vivo measurement of UAS PFOI may confirm a threshold. [ABSTRACT FROM AUTHOR]

The ureteral access sheath (UAS) has been a boon and a bane in flexible ureteroscopy (FURS), with its merits and demerits well established. Its design and dimensions were instrumental in reshaping the way flexible scopes were used and were key adjuncts to establishing retrograde intrarenal surgery (RIRS) as a standard of care in the endourological management of renal stones. With the ever-changing landscape of RIRS over the decades shaped by technological advancements in lasers and flexible scopes, the UAS has also continuously evolved. The utility of suction in endourology has recently changed the way RIRS is performed and is a game changer for FURS outcomes. With strong clinical and experimental evidence to support its use, the UAS has undergone a transformative change in the recent past, with its ability to monitor intrarenal pressure and provide a superior vacuum-cleaner effect that improves the trifecta of RIRS, namely an improved single-stage stone-free rate (SFR), minimise complications, and reduce reinterventions. Our comprehensive review outlines the key clinical and experimental evidence and traces the developments that were key to modifying the traditional UAS into a flexible and navigable suction ureteric access sheath (FANS) and highlights how the design and modifications, in turn, influence the ability to push the boundaries of RIRS. [ABSTRACT FROM AUTHOR]

Purpose: Residual fragments not removed with urinary stone surgery may become symptomatic. In this context, this study was carried out to investigate the effect of performing retrograde intrarenal surgery, which is conventionally performed in the lithotomy position, in the modified lithotomy position (Trend-side) on stone-free rates following the surgery. Methods: This prospective study consisted of 100 patients with a single kidney stone smaller than 2 cm between 2021 and 2023. These patients were randomized into two groups of 50 patients each to be operated on in the conventional lithotomy and Trend-side positions. Variables were compared using independent t test for continuous variables and chi-square test for categorical variables. Results: There was no significant difference between the lithotomy and Trend-side position groups in terms of preoperative size, density, location of the stone, and hydronephrosis degree. Stone-free rate was 72% (n = 36) in the lithotomy group and 92% (n = 46) in the Trend-side group. Hence, there was a significant difference between the groups in the stone-free rate in favor of the Trend-side group (p = 0.009). Fragmentation time was statistically significantly shorter in the Trend-side group than in the lithotomy group (34 ± 17 min vs. 43 ± 14 min; p = 0.006). There was no significant difference between the groups in postoperative complication rates. Conclusion: Performing retrograde intrarenal surgery in the Trend-side position shortened the duration of fragmentation compared to the lithotomy position and was associated with higher stone-free rates. In conclusion, the Trend-side position can be safely preferred in patients undergoing retrograde intrarenal surgery due to kidney stones. [ABSTRACT FROM AUTHOR]

Objective: To report the initial results of an randomized clinical trail comparing the safety and efficacy between 7.5F and 9.2F flexible ureteroscope (FUS) in the management of renal calculi <2 cm. Materials and Methods: Eighty patients were enrolled and received retrograde intrarenal surgery (RIRS) with a different size FUS. The operation results and complications were compared. Results: Two cases in the 7.5F group and four cases in the 9.2F group failed to insert the 12/14F ureteral access sheath (UAS), respectively, and no significant difference (p = 0.396) was noted. However, 10/12F UAS was inserted in the 7.5F group, but not available in the 9.2F group, and thus, the 10/12F UAS inserting rate in the 7.5F group was higher than in the 9.2F group (100% vs 0%, p = 0.014), and the UAS insertion failure rate in 9.2F group was higher than in the 7.5F group (10% vs 0%, p = 0.040). The operation time in 7.5F group was shorter than the 9.2F group (35.60 ± 7.86 vs 41.05 ± 8.14, p = 0.003). Less irrigation was required in 7.5F group (813.93 ± 279.47 mL vs 1504.18 ± 385.31 mL, p = 0.000). The postoperative fever rate in 9.2F group was higher than 7.5F group (20% vs 5%, p = 0.043). There was no significant difference in sepsis (0% vs 2.5%, p = 0.314) between the two groups. No significant difference was noted in hospital stay (0.93 ± 0.49 days vs 1.14 ± 0.64 days, p = 0.099) between the two groups. The final stone-free rate (SFR) in 7.5F group was higher than 9.2F group (95% vs 80%, p = 0.043). Conclusion: The latest 7.5F mini FUS was a reliable instrument in RIRS to keep a good visualization with low requirement of irrigation, low postoperative infection complication, and also a high SFR when compared with the conventional 9.2F FUS. Clinical Trial Registration: NCT05231577. [ABSTRACT FROM AUTHOR]

Backgrounds: In the renal intrarenal stone surgery (RIRS) procedure, ureteral access sheath (UAS) is still used in the majority of surgeries to both protect the flexible ureteroscope (FURS) and reduce intrarenal pressure. ClearPETRA is a new UAS that has an integrated aspiration port. We aimed to evaluate the clinical outcomes and effectiveness of Aspiration-Assisted UAS (ClearPETRA) in the RIRS procedure. Methods: One thousand six hundred twenty patients who underwent RIRS between January 2021 and January 2024 were evaluated retrospectively and 512 patients were included in the study. According to stone size, patients with stones less than 2 cm and those with stones between 2 and 3 cm were analyzed separately. Patient's demographic data, stone size, body mass index, Extracoporeal Shockwave Lithotripsy (ESWL) history, stone side, stone density (Hounsfield Unit), operation time, stone-free rate (SFR), and the number of patients with sepsis were recorded. SFR was evaluated with kidney urinary bladder 3 months after surgery for opaque calculi. Nonopaque calculi patients were evaluated with noncontrast computed tomography 3 months after surgery. In the postoperative evaluation, patients with stones less than 4 mm were evaluated as SFR. P value of <0.01 was considered statistically significant. Results: Patient's demographic data, stone characteristics, and history of ESWL were similar in the ClearPETRA and UAS groups (P > .05). A total of 328 patients who underwent RIRS for stones less than 2 cm were included (80 ClearPETRA, 248 UAS). Length of hospital stay, operation time, SFR, secondary intervention, or postoperative sepsis (P ≥ .01) were similar in both groups. The incidence of postoperative fever was statistically significantly lower in the ClearPETRA group (P = .006). A total of 184 patients who underwent RIRS for stones between 2 and 3 cm were included (42 ClearPETRA, 142 UAS). In the ClearPETRA group, operation time was statistically significantly shorter (P = .002), SFR was statistically significantly higher (P = .003), and the number of fever and sepsis were statistically significantly less (P = .003 and 0.002, respectively). Conclusion: We found that ClearPETRA reduces the likelihood of postoperative fever after RIRS surgeries. Moreover, we can say that the use of ClearPETRA in RIRS, especially for stones larger than 2 cm, reduces the operation time, increases the SFR, and also reduces sepsis rates. [ABSTRACT FROM AUTHOR]

Introduction: Thermal damage to the kidney during holmium laser lithotripsy is a serious complication, which cannot always be prevented considering the diversity of conditions in the kidney and the lack of technical capability to measure intrarenal temperature in real-time. The aim of this study was to analyze the impact of different power settings of the holmium laser and the flow rate of irrigation fluid conditioned by the size of the sheath on the fluid temperature in a model of the pelvicalyceal system during lithotripsy. Materials and Methods: A lithotripsy of artificial stones was performed in a 3D-printed model of the renal pelvicalyceal system with a volume of 20.5 mL. A gravity-driven fluid flow was applied (p = 60 cm H2O). A 9.2Fr ureteroscope was introduced into the model through a ureteral access sheath of either 10/12Fr or 12/14Fr. Lithotripsy power ranged from 12 to 25 W. Temperature was measured using thermography. Results: For the 10/12Fr ureteral access sheath, the fluid flow rate was 2.7 mL/min, with the maximum temperature reached within 20 min ranging from 45 to 50 °C. For the 12/14Fr ureteral access sheath, the fluid flow rate was 9.8 mL/min, with the achieved temperature ranging from 35 to 45 °C. Laser power influenced the rate of temperature increase and the maximum temperature reached. During the first 5 min, the rate of temperature increase was solely dependent on laser power, not on the flow rate. Temperatures of 40 °C were only not exceeded with high flow rates (12/14Fr sheath) and power below 20 W. Conclusions: In a short period, the rate of temperature increase depends solely on laser power, not on the irrigation flow rate. During prolonged lithotripsy, the maximum temperature value depends on both parameters. [ABSTRACT FROM AUTHOR]

Background: The management of renal stones measuring 1-2 cm has evolved with the introduction of miniaturized percutaneous nephrolithotomy (mini-PCNL) and retrograde intrarenal surgery (RIRS). These procedures offer less invasive alternatives to standard PCNL, aiming to reduce complications and improve patient outcomes. While guidelines traditionally favor PCNL for stones larger than 2 cm and RIRS for smaller stones, mini-PCNL is emerging as an effective option even for smaller stones. Economic considerations further influence the choice of treatment, particularly in resource-constrained settings. Methods: This study compared local clinical outcomes of mini-PCNL and RIRS in managing renal stones of 1-2 cm in a tertiary care hospital in central India. The study included 55 patients undergoing RIRS (Group 1) and 45 patients undergoing mini-PCNL (Group 2), performed by a single surgeon. Preoperative assessments, surgical techniques, and postoperative follow-up protocols were standardized across both groups. Statistical analyses were conducted to evaluate differences in demographic features, stone characteristics, surgical features, and complications between the two groups. Results: Comparison of demographic and stone characteristics revealed no significant differences in age, gender distribution, or body mass index (BMI) between Group 1 and Group 2. However, comorbid disorders differed significantly, with Group 1 showing a higher prevalence of hypertension (ht), diabetes mellitus (dm), chronic obstructive pulmonary disease (COPD), and antiplatelet medication use. Stone size was slightly larger in Group 2.Surgical features analysis demonstrated that mini-PCNL (Group 2) had shorter operation and fluoroscopy times compared to RIRS (Group 1). Hemoglobin levels decreased significantly post-operation in both groups, with a greater reduction observed in Group 2. Stone-free rates (SFR) at different time points were similar between the groups, but Group 2 reported higher visual analog scale (VAS) pain scores and longer hospital stays. Group 1 also required more general anesthesia. Conclusion: In conclusion, mini-PCNL and RIRS are both effective methods for managing renal stones measuring 1-2 cm. Mini-PCNL offers advantages in terms of shorter surgical duration and potentially higher stone-free rates, albeit with higher postoperative pain and longer hospital stays compared to RIRS. RIRS, on the other hand, shows benefits in terms of reduced pain, lower analgesic requirements, and shorter hospitalization. The choice between these techniques should consider patient-specific factors, including stone location, comorbidities, and economic considerations, to optimize outcomes and patient satisfaction. [ABSTRACT FROM AUTHOR]

Objective: The aim of the article is to assess the impact of retrograde intrarenal surgery under central neuraxial blockade in comparison to general anesthesia (GA). Material and Methodology: This systematic review was conducted following the guidelines set out by the preferred reporting items for systematic reviews and meta-analyses. We conducted a comprehensive search across major electronic databases, including various types of studies such as descriptive studies and full-text literature, all of which were incorporated into the current review from 2018 to 2023. We involved those studies, which included the comparative study of spinal anesthesia (SA), epidural anesthesia (EA), and combined spinal epidural anesthesia with GA. Result: In our meta-analysis of 12 studies, it was found that anesthesia technique significantly affected operation time, with neuraxial anesthesia (NA) showing a mean difference of -2.28 (95% confidence interval (CI): -3.5 to -1.04, P = 0.003) compared to GA. However, there were no significant differences in rates of stone clearance, 24-h pain scores and length of hospital stay among patients administered with NA or GA for retrograde intrarenal surgery (RIRS). Conclusion: On the basis of the outcomes of study, NA can serve as a viable alternative to GA for RIRS. Our analysis reveals no significant differences in rates of stone clearance, operation duration, 24-h pain scores, complication rates, and length of hospital stay between NA in addition to GA in the context of RIRS. This suggests that given the potential economic advantages, NA might be a preferable choice over GA, contingent on patient preferences, baseline characteristics, and stone burden. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association between psoas muscle mass (PMM) and failure of ureteral access sheath (UAS) insertion and complications from retrograde intrarenal surgery (RIRS). Materials and Methods: A multicenter retrospective case–control study was conducted that included patients who underwent RIRS despite failure of UAS insertion (Cohort 1) and confounder-matched control patients who underwent RIRS after successful UAS insertion (Cohort 2). For morphometric analysis of PMM, ipsilateral psoas muscle areas (iPMAs) were measured using the coreslicer.com webkit. After comparing demographic, clinical, and complication rates and iPMAs between cohorts, gender-specific median iPMAs were also determined to further subdivide patients in each cohort as either low iPMAs or high iPMAs. Thereafter, patients were also compared in terms of RIRS complications. Results: Cohort 1 included 86 patients whereas Cohort 2 consisted of 124 matched cases. The median (interquartile range) iPMAs were similar between the cohorts: Cohort 1, 11.05 (6.82–14.44) cm2 versus 11.12 (6.97–13.69) cm2 for Cohort 2 (P ˃.05). There was a significant inverse relationship between iPMAs with age (r = −0.222) and Charlson comorbidity index (r = −0.180) for all patients (P ˂.05). Perioperative and postoperative complication rates were 8.1% and 16.3% for Cohort 1 and 6.5% and 21% for Cohort 2, respectively. The complication rates were not statistically different between patients with high iPMAs and those with low iPMAs, in male or female patients (P > .05). Conclusions: These results show that failure of UAS was not associated with PMM. Furthermore, since the complication rates were similar between patients with high PMM and low PMM, RIRS may be a reliable treatment choice for sarcopenic patients as well as in nonsarcopenic patients. [ABSTRACT FROM AUTHOR]

Purpose: Renal cysts are typically a benign condition, and parapelvic cysts are a type of renal cyst that occur adjacent to the renal pelvis or renal sinus. Parapelvic cysts can increase the risk for injury to adjacent organs or urine leakage during laparoscopic surgery. Flexible ureteroscopes with laser assistance were used to make internal incisions in cysts. Perioperative outcomes of this method were compared with those of laparoscopic surgery. Methods: Eight-three patients, who underwent surgical treatment for renal cysts at the authors' medical center between January 2019 and June 2022, were evaluated. Two patients were excluded because they originally opted for RIRS but subsequently converted to laparoscopic surgery. Patients were divided into 2 groups based on surgery type: laparoscopic; and RIRS for internal incision. Outcomes in both groups were analyzed. Results: Of the 81 patients analyzed, 60 [74% (group 1)] underwent laparoscopic surgery and 21 [26% (group 2)] underwent RIRS for internal incision. The median operative durations for groups 1 and 2 were 87 and 56 min, respectively (p < 0.001). Relative to RIRS, laparoscopic surgery resulted in greater postoperative painkiller use (laparoscopic surgery versus [vs.] RIRS, 43% vs. 19%; p = 0.047). The median length of hospital stay was 2 and 1 days, respectively (p < 0.001). Conclusions: RIRS demonstrated several advantages over laparoscopic surgery for the internal incision of parapelvic cysts, including shorter operative duration, shorter hospital stay, and less postoperative pain control. These findings may guide the selection of appropriate surgical approaches for patients with renal cysts. [ABSTRACT FROM AUTHOR]

Abstract To compare the safety and effectiveness of the combination of intelligent intrarenal pressure control platforms (IPCP) and flexible ureteral access sheath (FUAS) combined with retrograde intrarenal surgery (RIRS) for the treatment of renal stones less than 2 cm. We retrospectively collected 383 patients with renal stones who underwent RIRS in our department from June 2022 to October 2023. Inclusion criteria: stone length or the sum of multiple stone lengths ≤ 2 cm. Finally, 99 cases were included and divided into an IPCP group (n = 40) and FUAS group (n = 59) based on surgical methods. The main endpoint was the stone-free rate (SFR) at third months after surgery, with no residual stones or stone fragments less than 2 mm defined as stone clearance. The secondary endpoints were surgical time and perioperative complications, including fever, sepsis, septic shock, and perirenal hematoma. There was no statistically significant difference in general information between the two groups, including age, gender, body mass index, comorbidities, stone side, stone location, stone length, urine bacterial culture, and hydronephrosis. The operation time for IPCP group and FUAS group was 56.83 ± 21.33 vs 55.47 ± 19.69 min (p = 0.747). The SFR of IPCP group and FUAS group on the first postoperative day was 75.00% vs 91.50% (p = 0.024). The SFR was 90.00% vs 94.90% in the third month (p = 0.349).In IPCP group, there were 11 cases with stones located in the lower renal calyces and 17 cases in FUAS group. The SFR of the two groups on the first day and third months after surgery were 45.50% vs 88.20% (p = 0.014) and 63.60% vs 94.10% (p = 0.040), respectively, with statistical differences. For kidney stones ≤ 2 cm, there was no difference in SFR and the incidence of infection-related complications between IPCP and FUAS combined with RIRS, both of which were superior to T-RIRS. For lower renal caliceal stones, FUAS has a higher SFR compared to IPCP.

Objective: To evaluate the effect of ureteral access sheath (UAS) use and calibration change on stone-free rate and complications of retrograde intrarenal surgery (RIRS). Methods: Data from 568 patients undergoing RIRS for kidney or upper ureteral stones were retrospectively included. Firstly, patients were compared after 1:1 propensity score matching, according to UAS usage during RIRS (UAS used [+] 87 and UAS non-used [−] 87 patients). Then all UAS+ patients (n=481) were subdivided according to UAS calibration: 9.5–11.5 Fr, 10–12 Fr, 11–13 Fr, and 13–15 Fr. Primary outcomes of the study were the success and complications of RIRS. Results: Stone-free rate of UAS+ patients (86.2%) was significantly higher than UAS− patients (70.1%) after propensity score matching (p=0.01). Stone-free rate increased with higher caliber UAS (9.5–11.5 Fr: 66.7%; 10–12 Fr: 87.0%; 11–13 Fr: 90.6%; 13–15 Fr: 100%; p

Crossed renal ectopia is a rare congenital malformation. Only 36 cases of crossed renal ectopia with calculus have been recorded in literature, even a few cases of urolithiasis in them have been surgically managed. The majority of cases in literature have been published as single case reports. We conducted a retrospective study of all the crossed renal ectopia cases admitted and managed in our department in the past 2 years. Among them, only one was without fusion. Youngest patient was 32-year-old male with crossed left kidney with calculus in the left kidney. Both the patients underwent retrograde intrarenal surgery (RIRS). Oldest patient was 80-year-old female with a right crossed kidney with pelvic calculus, who underwent open pyelolithotomy. Post-operative period was uneventful in all cases with complete stone clearance. Patients undergoing RIRS had less post-operative pain and were discharged early compared to open pyelolithotomy. RIRS is a safe and effective modality of treatment and can be considered as the first choice for the management of calculus in crossed renal ectopia in properly selected cases. However, in cases of huge stone burden and difficult anatomy, laparoscopic/open pyelolithotomy is still an attractive option for clearing the stone in a single setting, even though it has comparatively more morbidity and longer hospital stay.

This article discusses the use of robot-assisted retrograde intrarenal surgery (roboRIRS) for the treatment of urinary stones. The article explains that while flexible ureteroscopy (fURS) is commonly used for stone treatment, it has ergonomic limitations and can be challenging in complicated cases. The introduction of robotics in endourological interventions, such as roboRIRS, aims to improve surgical outcomes, ergonomics, and surgeon health. The article describes the ILY® robotic system, a compact trolley mini-console operated remotely by a wireless controller, which offers potential benefits in terms of ergonomics and reduced radiation exposure. The article presents a case series of six patients who underwent roboRIRS using the ILY robot, demonstrating its feasibility and safety. The authors suggest that further investigations are needed to evaluate the real-life benefits and cost-effectiveness of this technology. [Extracted from the article]

Background and Objectives: Retrograde intrarenal surgery (RIRS) is a minimally invasive technique for nephrolithiasis. RIRS is performed via a monitor screen displaying a magnified surgical site. Respiration can affect the stability of the surgical view during RIRS because the kidneys are close to the diaphragm. The purpose of this trial is to compare the effect of anesthesia type on the stability of the surgical view during RIRS between spinal anesthesia and general anesthesia. Materials and Methods: Patients were allocated to the general anesthesia group or spinal anesthesia group. During surgery, movement of the surgical field displayed on the monitor screen was graded by the first assistant on a 10-grade numeric rating scale (0–10). Next, it was also graded by the main surgeon. After surgery, we evaluated the discomfort with the anesthesia method for all patients. Results: Thirty-four patients were allocated to the general anesthesia group and 32 patients to the spinal anesthesia group. The average values of the two surgeons for surgical field oscillation grade showed vision on the monitor screen was more stable in the general anesthesia group than the spinal anesthesia group (3.3 ± 1.6 vs. 5.0 ± 1.6, p < 0.001). The degrees of the inconvenience of the surgery did not differ between the groups (0.7 ± 1.8 vs. 1.6 ± 2.6, p = 0.114), even though more patients reported inconvenience with a grade of 3 or more in the spinal anesthesia group (8.8% vs. 28.1%, p = 0.042). Conclusions: In terms of the visualization of the surgical site, general anesthesia might provide a more stable surgical view during RIRS compared to spinal anesthesia without increasing inconvenience induced by the type of anesthesia.