Final Stone-free Rate Research Articles

7.5F Mini Flexible Ureteroscope in Retrograde Intrarenal Surgery: Initial Results from a Multicenter Randomized Clinical Trial.

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.

Clinical Efficacy Evaluation of a Novel Negative Pressure Ureteroscopic Lithotripsy for Ureteral Stones

ObjectiveTo evaluate the clinical efficacy of a novel negative pressure ureteroscopic lithotripsy (NP-URL) compared to standard ureteroscopic lithotripsy (S-URL) for treating ureteral stones. MethodsA total of 284 patients diagnosed with ureteral stones and who underwent ureteroscopic lithotripsy between December 2020 and May 2022 at our hospital were included in the study. Among them, 146 cases underwent NP-URL and 138 cases underwent S-URL. The negative pressure device used in NP-URL consists of a 5F ureteric catheter and a tee joint. We evaluated the operative duration, stone-free rate, incidence of postoperative complications, stone retropulsion rate, and adjunct procedure rate between the two groups. ResultsThe mean operative duration was significantly shorter in the NP-URL group compared to the S-URL group (30.17±5.84 mins vs. 34.84±6.62 mins; P＜0.05). Additionally, the NP-URL group had a lower incidence of postoperative fever (1.4% vs. 8.7%; P＜0.05), reduced stone retropulsion rate (3.4% vs. 11.6%; P＜0.05), and a statistically lower rate of adjunct procedures (5.5% vs. 14.5%, P＜0.05). The NP-URL group also demonstrated a higher primary stone-free rate (91.8% vs. 81.9%; P＜0.05). However, there was no significant difference in the final stone-free rate between the NP-URL and S-URL groups (P＞0.05). ConclusionsNP-URL potentially reduces operative duration, significantly decreases the incidence of postoperative complications, and achieves better primary stone-free rates compared to S-URL.

A novel double-sheath negative-pressure versus conventional minimally invasive percutaneous nephrolithotomy for large kidney stone

This study aims to evaluate the therapeutic efficacy of a novel double-sheath negative-pressure minimally invasive percutaneous nephrolithotomy (D-mPCNL) compared to conventional minimally invasive percutaneous nephrolithotomy (C-mPCNL) for large kidney stones. A total of 132 patients diagnosed with large kidney stones in our hospital were included in the study. Among them, sixty-eight patients underwent D-mPCNL, while sixty-four underwent C-mPCNL. Parameters such as operative duration, stone-free rate, incidence of postoperative complications, and the need for auxiliary procedures were evaluated between the two groups. Compared to the C-mPCNL group, the D-mPCNL group demonstrated a significantly shorter operative time (41.97 ± 8.24 min vs. 52.30 ± 13.72 min; P < 0.000), lower rates of auxiliary procedures (5.9% vs. 17.2%; P = 0.041), and lower fever rates (2.9% vs. 14.1%; P = 0.021). The group also had a significantly higher primary stone-free rate (85.3% vs. 70.3%; P = 0.038). However, there were no statistically significant advantages in terms of the final stone-free rate, hemoglobin drops, and stone composition in the D-mPCNL group (P > 0.05). D-mPCNL is a novel surgical method that is safe and effective, reducing operative time, improving stone-free efficiency, and decreasing postoperative complications.

Mini-percutaneous nephrolithotomy: Is smaller better for kidney stones in patients with neurogenic bladder?

IntroductionPatients with neurologic bladder are at an increased risk for urolithiasis, and currently, data on mini-percutaneous nephrolithotomy in this population are limited. Our objective was to compare mini (15F)-percutaneous nephrolithotomy, standard (24F)-PCNL and flexible ureteroscopy in terms of efficacy and safety in treatment of kidney stones in patients with neurogenic lower urinary tract dysfunction (NLUTD). MethodsWe conducted a retrospective monocentric study in our neuro-urological referral centre. All consecutive patients with NLUTD and a cumulative size of renal calculi greater than 15mm or 10mm in the lower calyx, who had extraction surgery between 2005 and 2020, were included. The primary endpoint was the one-session stone-free rate (SFR) at 3 months on a CT scan. The secondary endpoints were complication (Clavien-Dindo grading system), operative time, blood loss and length of hospital stay. ResultsWe performed 76 standard PCNL (sPCNL), 46 flexible ureteroscopy lithotripsy (fURL) and 25 miniaturized PCNL (mPCNL). The one-session SFR was 37.5% for the mPCNL group, 38.2% for the sPCNL group and 37% for the fURL group with no significant difference between the three procedures (P=0.99). Early complications, blood loss and transfusion rates were lower in the mPCNL group than in the sPCNL group (P=0.047) and comparable to fURL group. The final SFRs after a second intervention for mPCNL, sPCNL and fURL were 48%, 61.8% and 63%, respectively (P=0.67). ConclusionThe efficacy of mPCNL in patients with NLUTD was not different from other techniques, but a significantly lower rate of complications than sPCNL was observed. Level of proof3.

Ureteroscopy and lasertripsy with pop dusting using high power holmium laser for large urinary stones > 15mm: 6.5-year prospective outcomes from a high-volume stone center.

Ureteroscopy and stone lasertripsy (URSL) is a recognized technique for treatment of urinary tract stones. Holmium:Yag laser has been successfully used for this purpose for the last two decades. More lately, pulse modulation with Moses technology and high power lasers have been introduced with the result of faster and more efficient stone lasertripsy. Pop dusting is a two-stage combined treatment using a long pulse Ho:YAG laser, initially in contact mode with the stone 'dusting' (0.2-0.5J/40-50Hz) followed by non-contact mode 'pop-dusting' (0.5-0.7J/20-50Hz). We wanted to look at the outcomes of lasertripsy for renal and ureteric stones using a high-power laser machine. Over a period of 6.5years (January 2016-May 2022), we prospectively collected data for patients undergoing URSL for stones larger than 15mm treated using high power Ho:YAG laser (60W Moses or 100W laser). Patient parameters, stone demographics and outcomes of URSL were analyzed. A total of 201 patients, underwent URSL for large urinary stones. In 136 patients (61.6%) stones were multiple and the mean single and cumulative stone size was 18mm and 22.4mm respectively. A pre- and post-operative stent was placed in 92 (41.4%) and 169 (76%) respectively. The initial and final stone free rate (SFR) were 84.5% and 94% respectively and 10% patients underwent additional procedure to achieve stone free status. 7 (3.9%) complications were recorded, all related to UTI/sepsis, with 6 Clavien II and 1 Clavien IVa complication. Dusting and pop-dusting has shown to be successful and safe with the ability to treat large, bilateral or multiple stones with low retreatment and complication rates.

Mini-Perc for Renal Stones-A Single Center Experience and Literature Review.

The aim of this study was to analyze the outcomes of miniaturized nephrolithotomy (mini-perc) in the management of renal stones with a diameter smaller than 20 mm. We retrospectively reviewed the records of 102 patients who underwent mini-perc between March 2015 and March 2020 in our department. The primary objective was the stone-free rate, but we also analyzed the retreatment rate, complications, hospital stay, operative time and reduction in hemoglobin level. All these patients had this technique as their first-line treatment, in a prone position, using a 16 Fr sheath size. Data were compared to a series of patients from the literature, treated with conventional PCNL. The patients had calculus limited to either a single calyx or just extending to the renal pelvis, and stone size was less than 20 mm in its maximal dimension. The intrarenal stone location was in the upper calyx in 7 cases, middle calyx in 20 cases and lower calyx in 46 cases, and there were 29 patients with renal pelvis stone. The male to female ratio was 1.5:1, and the median age was 48.4 years. The average stone size was 17.4 mm in diameter (ranging between 9 and 20 mm) and all cases underwent Ho-YaG laser lithotripsy, ballistic energy and combined ultrasonic and ballistic lithotripsy. At the end of the procedure, an antegrade double J stent was placed under fluoroscopy for a maximum of 2 weeks in 42 cases, while 9 cases needed a nephrostomy tube 12-14 F. A total of 51 cases were totally tubeless. Our median operative time was 61 min (ranging from 35 to 75 min). The median hospitalization stay was 3.8 days. The stone free rate was 90.1% after one procedure, only nine (8.8%) cases needed a "second look" flexible ureteroscopy, and the final stone-free rate was 98% (absence of detectable calculi on ultrasound, KUB or non-contrast CT scan). The overall complication rate was 6.86% (Clavien classification I-57.14%; II-28.5%; III-14.2%), while no Clavien IV or V complications were reported. No patient required a blood transfusion, and mean hemoglobin loss was 0.81 mg/dL. Overall, our results are better than similar data for conventional PCNL in the literature. The "mini-perc" technique is an effective procedure for the treatment of the renal lithiasis that is less or equal to 2 cm. The results demonstrated that this minimally invasive technique is associated with a higher stone-free rate and minimal complications.

Nonpapillary prone endoscopic combined intrarenal surgery: effectiveness, safety and tips, and tricks

PurposeTo evaluate the effectiveness and safety of nonpapillary prone endoscopic combined intrarenal surgery (ECIRS) and provide practical tips and tricks for the successful accomplishment of the procedure respecting the anatomical particularities.Material and methodsThis study is an analysis of a prospectively collected database including all cases of ECIRS performed between January 2019 and December 2021 in a high-volume tertiary center. All patients underwent the procedure in prone-split leg position. A nonpapillary renal puncture was performed. The used access sheaths were 22Fr or 30Fr. Lithotripsy was performed anterogradely with a dual-energy lithotripter with incorporated suction and retrogradely with holmium Yttrium–Aluminum–Garnet laser.ResultsA total of 33 patients were included. The initial stone-free rate (SFR) was 84.8% and the final SFR was 90.9%. The median stone size was 35 mm and 60% of patients had staghorn calculi. The prevalence of renal abnormalities was 21.3%, including 3 cases of horseshoe kidney, 2 cases of malrotation and 2 cases with complete duplicated systems. The median operative time was 47 min. The median hospital stay was 3 days and median hemoglobin loss was 1.2 gr/dL. Overall, the complication rate was 9.1%, all being Grade II complications (n = 2 fever and n = 1 transient bleeding).ConclusionsNonpapillary prone ECIRS is an effective and safe procedure. Standardization of the procedure is critical to achieve good outcomes. Patients who benefit the most are probably the ones where additional punctures can be avoided using this technique, namely patients with renal abnormalities, incrusted ureteral stents and staghorn stones.

Endoscopic Combined Intrarenal Surgery Versus Percutaneous Nephrolithotomy for Complex Renal Stones: A Systematic Review and Meta-Analysis.

Background: Endoscopic combined intrarenal surgery (ECIRS) adds ureteroscopic vision to percutaneous nephrolithotomy (PCNL), which can be helpful when dealing with complex renal stones. Yet, there is still no consensus on the superiority of ECIRS. We aimed to critically analyze the available evidence of studies comparing efficacy, safety, bleeding risk, and efficiency of ECIRS and PCNL. Methods: We searched for studies comparing efficacy (initial and final stone-free rate), safety (postoperative fever, overall and severe complications), efficiency (operative time and hospital stay) and bleeding risk between ECIRS and PCNL. Meta-analysis was performed. Results: Seven studies (919 patients) were identified. ECIRS provided a significantly higher initial stone-free rate, higher final stone-free rate, lower overall complications, lower severe complications, and lower rate of requiring blood transfusion. There was no difference between the two groups in terms of postoperative fever, hemoglobin drop, operative time, and hospital stay. In the subgroup analysis, both minimally invasive and conventional ECIRS were associated with a higher stone-free rate and lower complication outcomes. Conclusions: When treating complex renal stones, ECIRS has a better stone-free rate, fewer complications, and requires fewer blood transfusions compared with PCNL. Subgroups either with minimally invasive or conventional intervention showed a consistent trend.

One-stage tubeless percutaneous nephrolithotomy for asymptomatic calculous pyonephrosis

BackgroundIn recent years, the safety and effectiveness of one-stage percutaneous nephrolithotomy (PCNL) for the treatment of calculous pyonephrosis have been proven. In order to further reduce postoperative pain and hospital stay, we first proposed and practiced the idea of one-stage tubeless percutaneous nephrolithotomy for calculous pyonephrosis.MethodsA retrospective analysis was performed of case data of 30 patients with asymptomatic calculous pyonephrosis treated in our center with one-stage PCNL from January 2016 to January 2021. Patients were routinely given 20 mg of furosemide and 10 mg of dexamethasone sodium phosphate injection intravenously at the beginning of anesthesia. Among them, 27 patients successfully underwent one-stage tubeless percutaneous nephrolithotomy, while 3 cases were given indwelling nephrostomy tubes because of proposed second-stage surgery or the number of channels was greater than or equal to 3. All patients were operated on by the same surgeon.ResultsPreoperatively, 11 of 30 patients (8 men and 22 women) had positive urine bacterial cultures, and all were given appropriate antibiotics based on drug sensitivity tests. All patients completed the surgery successfully. The mean operative time was 66.6 ± 34.7 min, the mean estimated blood loss was 16.67 ± 14.34 mL and the mean postoperative hospital stay was 5.0 ± 3.1 days. The mean postoperative hospital stay was 4.6 ± 2.5 days among the 27 patients with one-stage tubeless percutaneous nephrolithotomy. Of the 3 patients with postoperative fever, 2 had the tubeless technique applied. One patient with 3 channels was given renal artery interventional embolization for control of postoperative bleeding. None of the 30 patients included in the study developed sepsis. The final stone-free rate was 93.3% (28/30) on repeat computed tomography at 1 month postoperatively. The final stone-free rate was 92.6% in the 27 patients undergoing one-stage tubeless percutaneous nephrolithotomy (25/27).ConclusionsOne-stage tubeless PCNL is an available and safe option in carefully evaluated and selected calculous pyonephrosis patients.

Prognostic factors for the safety and efficacy of retrograde laser lithotripsy: Data from a contemporary series of 155 consecutive patients with single and multiple lithiasis of the urinary tract.

Treatment of large and multiple stones located in the ureter and/or the kidney may be challenging. The aim of the current study was to evaluate the results and complications of retrograde endoscopic lithotripsy for stones located in the urinary tract and to determine prognostic factors for treatment outcome. From April 2017 to March 2020, eligible patients for the active treatment of ureterolithiasis with or without concomitant nephrolithiasis <20 mm were enrolled in the study. The prognostic factors for the stone free rate (SFR) after the 1st and subsequent sessions and overall complications were assessed. Patients were divided into single or multiple lithiasis groups (groups A and B respectively). A comparison between these two groups was then conducted. Overall, 237 stones were detected in 155 patients, representing a mean burden of 1.53 stone per patient. The mean total stone size was 14.7 mm, the initial SFR was 80% and the final SFR (after a mean of 1.23 session per patient) was 94.2%. The rate of complications was 26.4%. Multivariative analysis revealed that preoperative stenting and total stone size were independent prognostic factors of initial SFR, while no independent factors were determined for final SFR. Age, total size and stones in the lower calyx were independent factors for complications. In group A and B, 114 and 41 cases with solitary and multiple stones were included, respectively. Excluding operation time (P=0.002), no significant differences were recorded in terms of initial (P=0.255) and final SFR (P=0.056), hospital stay (P=0.308), mean number of treatments (P=0.757) and the rate of complications (P=0.218) between the two groups. In conclusion, retrograde endoscopic management of multiple lithiasis has a favorable outcome irrespective of stone location. Older patients with higher burdens and stones in the lower calyx should be treated with caution.

Single-Use vs. Reusable Digital Flexible Ureteroscope to Treat Upper Urinary Calculi: A Propensity-Score Matching Analysis.

Objective: The purpose of this research was to compare the treatment outcomes and costs of a single-use and reusable digital flexible ureteroscope for upper urinary calculi.Methods: Four hundred forty patients with reusable digital flexible ureteroscope and 151 patients with single-use flexible digital ureteroscope were included in this study. Through exclusion and inclusion criteria and 1:1 propensity-score matching analysis based on baseline characteristics, ultimately, 238 patients (119:119) were compared in terms of treatment outcomes. The cost analysis was based on the costs of purchase, repair, and reprocessing divided by the number of all procedures in each group (450 procedures with reusable digital flexible ureteroscope and 160 procedures with single-use digital flexible ureteroscope).Results: There was no statistical significance in mean operation time (P = 0.666). The single-use digital flexible ureteroscope group has a shorter mean length of hospital stay than the reusable digital flexible ureteroscope group (P = 0.026). And the two groups have a similar incidence of postoperative complications (P = 0.678). No significant difference was observed in the final stone-free rate (P = 0.599) and the probability of secondary lithotripsy (P = 0.811) between the two groups. After 275 procedures, the total costs of a single-use flexible ureteroscope would exceed the reusable flexible ureteroscope.Conclusion: Our data demonstrated that the single-use digital flexible ureteroscope is an alternative to reusable digital flexible ureteroscopy in terms of surgical efficacy and safety for upper urinary calculi. In terms of the economics of the two types of equipment, institutions should consider their financial situation, the number of FURS procedures, the volume of the patient's calculus, surgeon experience, and local dealerships' annual maintenance contract when making the choice.

Totally ultrasound-guided minimally invasive percutaneous nephrolithotomy in children: Is it safe?

Objective:The objective of the study was to assess the outcome and feasibility of ultrasonography (US)-guided minimally invasive percutaneous nephrolithotomy (mini-PCNL) in children.Materials and Methods:Twenty-five children with upper urinary tract stones who had undergone US-guided mini-PCNL from June 2017 to June 2020 were enrolled in this study. Patients’ demographic information and post-treatment results were retrospectively gathered and analysed. Pyelocaliceal system was punctured in prone position using US guidance, and the tract was dilated using single-shot dilation technique. All steps of renal access were done using only US. Mini-PCNL in all cases was done by using 15 Fr rigid nephroscope. Stones were fragmented with a pneumatic lithotripter and evacuated.Results:The patients’ mean age was 6.30 ± 3.25 years (range: 1.5–15). The mean stone size was 16.04 ± 3.93 mm (range: 10–30). The mean access time to the stone was 1.50 ± 0.62 min (range: 1–4). The mean operation time was 94.66 ± 3.05 min (range: 90–100 min). The final stone-free rate was 96%. Post-operation fever occurred in 4 (16%) patients who were treated successfully with an antibiotic. No major complications occurred.Conclusions:We recommend US-guided mini-PCNL as a harmless alternative treatment option, in children with renal calculi due to its excellent outcomes and little complications.

Laparoscopic ureterolithotomy versus percutaneous nephrolithotomy for large proximal ureteral stones: a systematic review and meta-analysis.

Both percutaneous nephrolithotomy (PCNL) and laparoscopic ureterolithotomy (LU) are effective treatment options for large proximal ureteral stones. To perform a meta-analysis on this topic to assess the efficacy, safety, and potential complications of the two procedures. A systematic literature search was performed using PubMed, Ovid and Scopus to identify eligible suitable studies until May 2022. All studies comparing LU vs PCNL in large proximal ureteral stones were included. The Cochrane Collaboration's Review Manager (RevMan) 5.4 software was used to analyze statistical significance. A total of nine publications involving 933 patients (LU 465; PCNL 468) were included, of which 4 were randomized control trails (RCTs) and 5 were non-RCTs. The meta-analysis of available data showed that compared with PCNL, LU had a higher initial stone-free rate (OR = 3.26; p = 0.004), but longer operative time (WMD = 35.08 min; p = 0.0003). However, the final stone-free rate (OR = 2.08; p = 0.07) and length of hospital stay (WMD = 0.32 d; p = 0.48) were comparable between the two groups. Meanwhile, LU had a lower transfusion rate (OR = 0.13; p = 0.007) than PCNL. There was no significant difference in terms of complications (OR = 0.97; p = 0.84), Clavien-Dindo score ≥ 3 complications (OR = 1.03; p = 0.93), auxiliary procedures (OR = 0.44; p = 0.08), or ureteral stenosis (OR = 0.24; p = 0.13) between LU and PCNL. Our meta-analysis revealed that LU is a safe and feasible option for large proximal ureteral stones with a higher initial stone-free rate and lower transfusion rate compared with PCNL.

Ureteroscopy for stone disease in the paediatric population: lessons learned and outcomes in a Nordic setting.

Introduction:Paediatric stone disease is rare in the Nordic communities. Still, the condition can require surgical intervention in the form of ureteroscopy (URS). Here, we report outcomes achieved at a regional (tertiary) centre.Patients and methods:Retrospective analysis was performed of consecutive patients (<18 years of age) undergoing URS for stone disease between 2010 and 2021. Outcomes of interest included stone-free rate (SFR) determined using a definition of no residual fragments ⩾ 3 mm on imaging and complications classified according to Clavien–Dindo system.Results:In total, 23 patients underwent 47 URS procedures for a total of 31 stone episodes. Mean age was 9 (range 1–17) years and male-to-female ratio was 6:17. Overall, 35% had at least one medical comorbidity. Ultrasound determined preoperative stone status in 87%. Mean largest index and cumulative stone sizes were 9 (range 3–40) and 12 (range 3–40) mm, respectively. Overall, 32% had multiple stones. Lower pole was the commonest stone location (39%). No patients underwent elective pre-operative stenting. Ureteral access sheaths were not used in any cases. Access to upper urinary tract at first procedure was successful in 94%. Initial and final SFR was 61% and 90%, respectively. No intra-operative complications were recorded. Overall post-operative complication rate was 17.5%. Urinary tract infection (CD II) was the commonest adverse event (12.5%).Conclusion:Paediatric URS can be delivered in the setting of a regional centre without compromising outcomes. This includes when carried out by adult endourologists, without routine pre-stenting and omitting use of ureteric access sheath.

Ureteral access sheath-related injuries vs. post-operative infections. Is sheath insertion always needed? A prospective randomized study to understand the lights and shadows of this practice

ObjectiveTo compare intraoperative ureteral injuries in RIRS with UAS insertion with the rate of postoperative infections after RIRS without UAS insertion. Patients and methodsIn this randomized trial, patients who received an indication for RIRS between January 2017 and December 2017 were divided into two groups. Group A had no UAS insertion and Group B had UAS insertion. Post-Ureteroscopic Lesion Scale (PULS) grading was performed after UAS or flexible ureteroscope removal. Proximal, middle and distal ureteral lesions were evaluated and compared according to the PULS scale. Additionally, patients in both groups were followed postoperatively to assess any infective complication. ResultsThe evaluation comprised 181 patients, 89 for group A and 92 for group B. Overall stone-free rate, clinically insignificant residual fragments, and final stone-free rate were 41.4%, 53.5%, and 95%, respectively. There were 33 (37.1%) patients with ureteral lesions in group A while 42 (45.6%) patients had ureteral lesions in group B, with no significant difference. On the other hand, the overall presence of postoperative infection rate was much higher for Group A (37.1% vs 16.3% P = 0.03). ConclusionsUAS insertion does not result in a higher number of ureteral injuries. UAS insertion during RIRS allows a lower rate of postoperative infections. Clinical Trial Registration Number (ISRCTN registry number)55546280.

Double-Sheath Vacuum Suction Minimally Invasive Percutaneous Nephrolithotomy for Management of Large Renal Stones

Objectives: This study aimed to describe a novel double-sheath vacuum suction minimally invasive percutaneous nephrolithotomy (mini-PCNL) to overcome the deficiencies of the conventional procedure. Patients and Methods: Between March 2019 and December 2019, 65 patients (37 males and 28 females) with a mean age of 41 years (range 23–69) underwent mini-PCNL with double-sheath vacuum suction. It consisted of an F20 Y-shaped sheath as an outer sheath and an F16 Y-shaped sheath as an inner sheath, in which the inner sheath was longer than the outer sheath. The oblique arm of the outer sheath and the inner sheath was connected to the perfusion inflow and the vacuum suction, respectively. A 550-μm holmium-YAG laser was introduced for stone fragmentation through the working channel of the mini-nephroscope, which was no longer connected to the perfusion fluid. Results: All procedures were successful. Mean operation time was 50.2 min (range 39–83). Mean hemoglobin decrease was 5.2 g/L (range 1.0–15.5), and no patient needed a blood transfusion. One patient (1.5%) with low fever (<38°C) at day 1 had returned to normal at day 2 without administration of antibiotics. There were no Clavien grade 2–4 complications. Mean postoperative hospital stay was 2.4 days (range 2–6). The initial stone-free rate of PCNL was 81.53% (53 of 65 patients). One month after surgery, the final stone-free rate increased to 90.77% (59/65 patients). Conclusions: The double-sheath vacuum suction mini-PCNL is a safe and effective modality for large renal stones, which might increase the efficiency of stone extraction with low intrapelvic pressure.

Current status of thulium fibre laser lithotripsy: an up-to-date review.

To perform an up-to-date review to scope the current status of the thulium fibre laser (TFL) in the setting of stone lithotripsy and provide a guide for the clinical urologist. A review of world literature was performed to identify original articles on TFL for stone lithotripsy. Our clinical experiences of using the technology have also been shared. To date there have been 11 clinical studies published on TFL for stone lithotripsy. Three of these have been in the setting of miniaturised percutaneous nephrolithotomy (mini-PCNL) and the remainder have been on ureteroscopy (URS). There has only been one randomised study on this technology, which has been for URS. For URS, the range of settings has been 0.1-4J×7-300Hz for both URS and mini-PCNL. Stones ranging from 0.4-3.2 and 1.5-3cm have been treated with URS and mini-PCNL, respectively. The final stone-free rate for TFL has ranged from 66.6% to 100% and 85-100% for URS and mini-PCNL, respectively. The average length of stay ranged from 0.5 to 2.4days in the URS group, but no studies have been reported this for mini-PCNL. Operative times in all the studies (both URS and mini PCNL) were <60min. Initial clinical studies reveal that TFL appears to be efficacious in the setting of stone lithotripsy. However, further randomised trials are warranted to delineate its formal position, as well as determine the optimal settings for use in clinical practice.

Lesiones relacionadas con la vaina de acceso ureteral frente a infecciones postoperatorias. ¿Es siempre necesaria la inserción de la vaina de acceso? Estudio prospectivo aleatorizado para comprender las luces y sombras de esta práctica

ObjectiveTo compare intraoperative ureteral injuries in RIRS with UAS insertion with the rate of postoperative infections after RIRS without UAS insertion. Patients and methodsIn this randomized trial, patients who received an indication for RIRS between January 2017 and December 2017 were divided into two groups. Group A had no UAS insertion and Group B had UAS insertion. Post-Ureteroscopic Lesion Scale (PULS) grading was performed after UAS or flexible ureteroscope removal. Proximal, middle and distal ureteral lesions were evaluated and compared according to the PULS scale. Additionally, patients in both groups were followed postoperatively to assess any infective complication. ResultsThe evaluation comprised 181 patients, 89 for group A and 92 for group B. Overall stone-free rate, clinically insignificant residual fragments, and final stone-free rate were 41.4%, 53.5%, and 95%, respectively. There were 33 (37.1%) patients with ureteral lesions in group A while 42 (45.6%) patients had ureteral lesions in group B, with no significant difference. On the other hand, the overall presence of postoperative infection rate was much higher for Group A (37.1% vs 16.3% P=.03). ConclusionsUAS insertion does not result in a higher number of ureteral injuries. UAS insertion during RIRS allows a lower rate of postoperative infections.Clinical Trial Registration Number (ISRCTN registry number): 55546280.

Retrospective Analysis of the Factors Affecting Intraoperative and Immediate Postoperative Complications of Retrograde Intrarenal Surgery Classified by the Clavien and Satava Grading Systems.

Background: To classify intraoperative and postoperative complications using the modified Clavien classification system (MCCS) and modified Satava classification system (SCS) and to evaluate the parameters associated with complications in patients undergoing retrograde intrarenal surgery (RIRS) for renal and proximal ureteral stones. Materials and Methods: We performed a retrospective analysis of 949 patients who underwent RIRS for renal stones and proximal ureteral stones at two institutions between March 2015 and June 2020. Intraoperative complications were assessed using the SCS, and postoperative complications were graded according to the MCCS. Univariate and multivariate analyses were undertaken to determine predictive factors affecting complication rates. Results: The median stone size was determined as 13 mm (range 10-20 mm). The stone-free rate was 83.6% after the first intervention. Reprocedure was applied to 89 of the patients with residual stones and the final stone-free rate was 94.4% after reprocedure. According to SCS, the number of intraoperative events and complication incidences was 153 (16.1%). MCCS revealed postoperative complications in 121 (12.8%) patients. Major complications were observed in 18 (1.9%) patients. The rate of complications was higher in patients with renal anomalies (9.9% vs 3.4%, p = 0.001). Stone location, stone size, stone burden, stone number, stone density, and residual fragments were determined to be associated with the development of complications (p < 0.001, p < 0.001, p < 0.001, p < 0.001, p = 0.002, and p < 0.001, respectively). In addition, the multivariate analysis revealed that only the presence of residual fragments was a significant predictor of complication development for the patients with Grade ≥3 complications according to MCCS (p = 0.032). However, significant predictors were stone burden (p < 0.001), stone density (p = 0.002), and fluoroscopy time (p < 0.001) for those with Grade ≥2b complications according to SCS. Conclusion: This study showed that abnormal kidney anatomy, operation time, stone burden, and residual fragments were reliable predictors of complication development during and after RIRS. Appropriate preoperative management should be planned according to these predictors to prevent intraoperative and postoperative complications.

Outcomes of Ureteroscopy and Laser Stone Fragmentation (URSL) for Kidney Stone Disease (KSD): Comparative Cohort Study Using MOSES Technology 60 W Laser System versus Regular Holmium 20 W Laser.

Background: For ureteroscopy and laser stone fragmentation (URSL), the use of laser technology has shifted from low power to higher power lasers and the addition of Moses technology, that allows for ‘fragmentation, dusting and pop-dusting’ of stones. We wanted to compare the outcomes of URSL for Moses technology 60 W laser system versus matched regular Holmium 20 W laser cases. Methods: Prospective data were collected for patients who underwent URSL using a Moses 60 W laser (Group A) and matched to historical control data using a regular Holmium 20 W laser (Group B), performed by a single surgeon. Data were collected for patient demographics, stone location, size, pre- and post-operative stent, operative time, length of stay, complications and stone free rate (SFR). Results: A total of 38 patients in each group underwent the URSL procedure. The stones were matched for their location (17 renal and 11 ureteric stones). The mean single and cumulative stone sizes (mm) were 10.9 ± 4.4 and 15.5 ± 9.9, and 11.8 ± 4.0 and 16.5 ± 11.3 for groups A and B, respectively. The mean operative time (min) was 51.6 ± 17.1 and 82.1 ± 27.0 (p ≤ 0.0001) for groups A and B. The initial SFR was 97.3% and 81.6% for groups A and B, respectively (p = 0.05), with 1 and 7 patients in each group needing a second procedure (p = 0.05), for a final SFR of 100% and 97.3%. While there were 2 and 5 Clavien I/II complications for groups A and B, none of the patients in group A had any infection related complication. Conclusions: Use of Moses technology with higher power was significantly faster for stone lithotripsy and reduced operative time and the number of patients who needed a second procedure to achieve a stone free status. It seems that the use of Moses technology with a mid-power laser is likely to set a new benchmark for treating complex stones, without the need for secondary procedures in most patients.