International Alliance of Urolithiasis guideline on retrograde intrarenal surgery.

OBJECTIVES: To set out the second in a series of guidelines on the treatment of urolithiasis by the International Alliance of Urolithiasis that concerns retrograde intrarenal surgery (RIRS), with the aim of providing a clinical framework for urologists performing RIRS. MATERIALS AND METHODS: After a comprehensive search of RIRS-related literature published between 1 January 1964 and 1 October 2021 from the PubMed database, systematic review and assessment were performed to inform a series of recommendations, which were graded using modified GRADE methodology. Additionally, quality of evidence was classified using a modification of the Oxford Centre for Evidence-Based Medicine Levels of Evidence system. Finally, related comments were provided. RESULTS: A total of 36 recommendations were developed and graded that covered the following topics: indications and contraindications; preoperative imaging; preoperative ureteric stenting; preoperative medications; peri-operative antibiotics; management of antithrombotic therapy; anaesthesia; patient positioning; equipment; lithotripsy; exit strategy; and complications. CONCLUSION: The series of recommendations regarding RIRS, along with the related commentary and supporting documentation, offered here should help provide safe and effective performance of RIRS.

Radiation exposure of patients during endourological procedures: IAEA-SEGUR study.

Fluoroscopy is increasingly used to guide minimally invasive endourological procedures and optimised protocols are needed to minimise radiation exposure while achieving best treatment results. This multi-center study of radiation exposure of patients was conducted by the South-Eastern European Group for Urolithiasis Research (SEGUR), in cooperation with the International Atomic Energy Agency. Seven clinical centers from the SEGUR group collected data for 325 procedures performed within a three-months period, including standard percutaneous nephrolithotomy (PCNL), mini PCNL, retrograde intrarenal surgery (RIRS), semirigid ureterorenoscopy (URS) and flexible URS. Data included: air kerma area product (PKA), air kerma at the patient entrance reference point (Ka,r), fluoroscopy time (FT), number of radiographic images (N) and fluoroscopy pulse rate, as well as total procedure duration, size and location of stones. Data were centrally analysed and statistically compared. MedianPKAvalues per center varied 2-fold for RIRS (0.80-1.79 Gy cm2), 7.1 fold for mini-PCNL (1.39-9.90 Gy cm2), 7.3 fold for PCNL (2.40-17.50 Gy cm2), 19 fold (0.13-2.51 Gy cm2) for semi-rigid URS and 29-fold for flexible URS (0.10-2.90 Gy cm2). LowerPKAandKa,rwere associated with use of lower FT,Nand lower fluoroscopy pulse rate. FT varied from 0.1 to 14 min, a small fraction of the total procedure time, ranging from 10 to 225 min. HigherNwas associated with higherPKAandKa,r. Higher medianPKAin PCNL was associated with the use of supine compared to prone position. No correlation was found between the concrement size and procedure duration, FT,PKAorKa,r. Dose values for RIRS were significantly lower compared to PCNL. The maximumKa,rvalue of 377 mGy was under the threshold for radiation induced skin erythema. The study demonstrated a potential for patient dose reduction by lowering FT andN, using pulsed fluoroscopy and beam collimation.

The Urological Association of Asia clinical guideline for urinary stone disease.

The Urological Association of Asia, consisting of 25 member associations and one affiliated member since its foundation in 1990, has planned to develop Asian guidelines for all urological fields. The field of stone diseases is the third of its guideline projects. Because of the different climates, and social, economic and ethnic environments, the clinical practice for urinary stone diseases widely varies among the Asian countries. The committee members of the Urological Association of Asia on the clinical guidelines for urinary stone disease carried out a surveillance study to better understand the diversity of the treatment strategy among different regions and subsequent systematic literature review through PubMed and MEDLINE database between 1966 and 2017. Levels of evidence and grades of recommendation for each management were decided according to the relevant strategy. Each clinical question and answer were thoroughly reviewed and discussed by all committee members and their colleagues, with suggestions from expert representatives of the American Urological Association and European Association of Urology. However, we focused on the pragmatic care of patients and our own evidence throughout Asia, which included recent surgical trends, such as miniaturized percutaneous nephrolithotomy and endoscopic combined intrarenal surgery. This guideline covers all fields of stone diseases, from etiology to recurrence prevention. Here, we present a short summary of the first version of the guideline - consisting 43 clinical questions - and overview its key practical issues.

Optimal duration of medical expulsive therapy for lower ureteral stones: a critical evaluation.

To evaluate the optimal duration of Medical Expulsive Therapy (MET) application for distal ureteric stones on a time period based manner. 89 patients with 5-10 mm distal ureter stones received tamsulosin (0.4 mg) for MET and diclofenac sodium (75 mg) for analgesia. Patients were evaluated once a week for 4 weeks. Radiologic stone passage was evaluated by kidney ureter bladder (KUB) and ultasonography where non-contrast computed tomography (NCCT) was also performed if needed. While 23 cases (28.4%) were SF after first week, 23 were SF (28.4%) after 2 weeks, 9 cases (11.1%) after 3 and lastly 7 cases (8.6%) became SF after four weeks. Nineteen (23.5%) cases were not SF after 4 weeks. A positive relationship was found between the time period elapsed for stone passage and ureteral wall thickness (UWT) along with the degree of hydronephrosis. In addition, mean number of renal colics and emergency department (ED) visits were found to be higher in patients passing stones in the 4th week along with the ones who could not despite MET. SFR for distal ureteric stones sizing 5-10 mm was higher within the first 3 weeks under MET application. Thus, waiting for a longer period of time may result in increased analgesic and unnecessary MET treatment with increased risk of emergency department visits and additional costs as well. We believe that other options could be considered in such cases who are not SF at the end of the first 3 weeks.

Comparing Same-Sitting Bilateral vs Unilateral Retrograde Intrarenal Surgery in the Elderly.

OBJECTIVE: To compare same-sitting bilateral vs unilateral retrograde intrarenal surgery (RIRS) in elderly patients, focusing on postoperative complications and stone-free rates (SFR). METHODS: Data from 2 multicenter databases, FLEXible ureteroscopy Outcomes Registry (FLEXOR) (unilateral RIRS) and same sitting bilateral-retrograde intrarenal surgery (SSB-RIRS) (bilateral RIRS), were analyzed, considering only patients aged 70+ with preoperative computed tomography. Patients were categorized into Group 1 (bilateral RIRS) and Group 2 (unilateral RIRS). Follow-up included imaging assessments and secondary treatments as needed. RESULTS: Group 1 included 146 patients, while group 2 had 495. Group 1's patients were slightly older and had a higher prevalence of recurrent stone formation. Group 2 often underwent RIRS for incidental stones. Group 1 had larger and more pelvic stones. Laser lithotripsy and total operation times were significantly longer in Group 1. Group 2 had significantly higher overall stone-free rates, although there were no significant differences in ancillary procedures for residual fragments. Group 1 experienced more pelvicalyceal injuries needing stenting, postoperative fever, and post-op hematuria not requiring transfusion. CONCLUSION: In conclusion, bilateral RIRS can be carefully considered in elderly patients. Preoperative counseling is essential for both primary and repeat RIRS procedures, and further research is needed to optimize instrument and laser strategies for better outcomes in elderly RIRS patients.

Importance of precise imaging for stone identification during shockwave lithotripsy: a critical evaluation of "OptiVision" as a post-processing radiography imaging modality.

To evaluate the efficacy of a unique imaging software "OptiVision" on the confidence of stone identification using X-ray imaging during shockwave lithotripsy. A total of 57 patients with solitary radio-opaque kidney stones sized < 15 mm were included and evaluated with appropriate radiological imaging and laboratory studies before undergoing shockwave lithotripsy (SWL). The size of the stones was measured on KUB and CT images using maximal stone diameters. All patients were evaluated with radiography on the Dornier Delta III immediately before SWL and at the end of the SWL session with fluoroscopy, a snapshot image, and the OptiVision modality (applied over the acquired snapshot image without additional radiation exposure) for precise identification of the stone. All images obtained with these three different imaging modalities (fluoroscopy, snapshot, and OptiVision) were comparatively evaluated for confidence levels in stone identification using a five-point Likert scale (1 = poor diagnostic confidence, 5 = excellent diagnostic confidence). These confidence levels were also used to differentiate between stones and bony structures using these same imaging modalities. Results were evaluated for statistical significance regarding their impact on the precise identification of renal stones. A total of 57 patients with solitary stones were evaluated using flouroscopy, snapshot, and OptiVision images before and after SWL to ascertain the efficacy of these 3 imaging modalities on the precise identification of the calculi. Stone sizes ranged from 4 to 15 mm, with a mean of 8.30 mm in the longest dimension. Evaluation of the findings demonstrated that while the pre- and post-SWL confidence of fluoroscopic stone identification was from 29.51 to 31.15%, the values using snapshot ranged from 31.15 to 39.34%. Pre- and post-SWL confidence of stone identification with OptiVision post-processing imaging was approximately 89%. In the majority of cases (n = 43), the use of OptiVision image processing enabled urologists to identify the stone with a higher level of confidence rating than the use of both fluoroscopy (n = 0) and snapshot (n = 0) image processing tools. While a rating level of 4 or higher was given in 89% of images obtained by OptiVision during the pre- and post-SWL phase, this value was only 37% (4 or more points) using fluoroscopy and Snapshot image processing techniques. For all the radiography image processing tools, the distribution of the Likert score differed significantly among the OptiVision, fluoroscopy, and snapshot imaging modalities (p < 0.001). Precise and reliable identification of stone(s) located in the kidney is essential in delivering shock waves to the desired focal point and achieving higher stone-free rates. Our findings demonstrated that using the specially designed imaging modality OptiVision was significantly helpful in identifying and localizing stones with high-quality images before SWL for effective stone disintegration during this procedure.

Comparison of dusting and fragmentation methods in the flexible ureteroscopic treatment of kidney lower calyx stones.

To compare the long-term stone-free status of patients who underwent fragmentation of stones followed by active basketing versus stone dusting and spontaneous passage following flexible ureteroscopic treatment for lower calyceal stones. The dusting or fragmentation methods were randomly assigned to patients who were scheduled to undergo RIRS for only renal lower calyceal stones between February 2019 and May 2022, prospectively. Stone-free rates were determined after 3 months by non-contrast computed tomography and patient demography; preoperative and postoperative follow-up data of both groups were evaluated comparatively. While the fragmentation method was applied in 32 patients, the dusting method was applied in the remaining 31 cases. The two groups did not differ significantly regarding the demographic data and laboratory findings. Mean stone size was similar in both groups of cases. Operation time was significantly longer for fragmentation (93.23 ± 27.20 vs 78.43 ± 30.08, p = 0.045) and evaluation of the success rates after 3 months did show that patients in the dusting group had a higher rate of stone-free status when compared with the other group of cases (65.6 vs 87.1%, p = 0.043). Lastly, postoperative fever rates were not significantly different between the two groups (12.5 vs 9.7%, p = 0.518). Our findings showed that dusting the lower calyceal stones during fURS would reveal higher stone-free rates during long-term follow-up periods, and the mean operation time will be shorter in these patients.

International Alliance of Urolithiasis (IAU) Guideline on percutaneous nephrolithotomy.

The International Alliance of Urolithiasis (IAU) would like to release the latest guideline on percutaneous nephrolithotomy (PCNL) and to provide a clinical framework for surgeons performing PCNLs. These recommendations were collected and appraised from a systematic review and assessment of the literature covering all aspects of PCNLs from the PubMed database between January 1, 1976, and July 31, 2021. Each generated recommendation was graded using a modified GRADE methodology. The quality of the evidence was graded using a classification system modified from the Oxford Center for Evidence-Based Medicine Levels of Evidence. Forty-seven recommendations were summarized and graded, which covered the following issues, indications and contraindications, stone complexity evaluation, preoperative imaging, antibiotic strategy, management of antithrombotic therapy, anesthesia, position, puncture, tracts, dilation, lithotripsy, intraoperative evaluation of residual stones, exit strategy, postoperative imaging and stone-free status evaluation, complications. The present guideline on PCNL was the first in the IAU series of urolithiasis management guidelines. The recommendations, tips and tricks across the PCNL procedures would provide adequate guidance for urologists performing PCNLs to ensure safety and efficiency in PCNLs.

Classification and standardized reporting of percutaneous nephrolithotomy (PCNL): International Alliance of Urolithiasis (IAU) Consensus Statements.

BACKGROUND: The aim of this study was to reach a consensus in the classification and standardized reporting for the different types of PCNLs. METHODS: The RAND/UCLA appropriateness methodology was used to reach a consensus. Thirty-two statements were formulated reviewing the literature on guidelines and consensus on PCNLs, and included procedure specific details, outcome measurements and a classification for PCNLs. Experts were invited to two rounds of input, the first enabled independent modifications of the proposed statements and provided the option to add statements. The second round facilitated scoring of all statements. Each statement was discussed in the third round to decide which statements to include. Any suggestion or disagreement was debated and discussed to reach a consensual agreement. RESULTS: Twenty-five recommendations were identified to provide standardized reporting of procedure and outcomes. Consensual scoring above 80% were strongly agreed upon by the panel. The top treatment related outcomes were size of sheath used (99.1%) and position for PCNL (93.5%). The highest ranked Outcome Measures included definition of postoperative hospital length of stay (94.4%) and estimated blood loss (93.5%). CONCLUSIONS: The consensus statements will be useful to clarify operative technique, in the design of clinical trials and standardized reporting, and presentation of results to compare outcomes of different types of PCNLs.

Predictors and Strategies to Avoid Mortality Following Ureteroscopy for Stone Disease: A Systematic Review from European Association of Urologists Sections of Urolithiasis (EULIS) and Uro-technology (ESUT).

CONTEXT: While kidney stone disease is common and ureteroscopy (URS) is perceived as minimally invasive, there is mortality associated with treatment. OBJECTIVE: The aim of this review was to ascertain the number of mortalities from URS for stone disease over the past three decades, identify relevant patient risk factors and predictors of mortality, and summarise the key recommendations so that similar instances can be avoided, and lessons can be learnt. EVIDENCE ACQUISITION: A systematic literature search was conducted following Cochrane and Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) methodology for English-language article reporting on data from 1990 to December 2020. Data collated from each study included patient and stone characteristics, number of mortalities, and cause of death. EVIDENCE SYNTHESIS: Fifteen studies met our inclusion criteria and revealed a total of 72 mortalities from ten countries. The age range of reported patients varied from 21 to 89 yr, with over 60% being above 65 yr of age and 97% with some comorbidity. Based on available data, death reports in females were three times more than those in males. The stone size ranged from 10 to 38 mm. Treatment of larger stones corresponded to a longer operative time, with procedural duration varying from 30 to 120 min. Of the reported causes of mortality in 42 patients, the aetiology was sepsis in over half of the patients, with other causes being cardiac-related, respiratory-related, multiorgan failure, and haemorrhagic complications. CONCLUSIONS: Although the reported URS mortality rate seems to be low, there has been a rise in deaths over the past decade. Efforts must be made to have preoperative urine culture, and reduce operative time and stage procedures in patients with a large stone burden. Care must be taken in patients with robust preoperative assessment, intraoperative techniques, and postoperative monitoring for early detection of complications with interdisciplinary management of complex cases. PATIENT SUMMARY: We reviewed the risk factors associated with postureteroscopy mortality and ways to minimise this. Evidence shows that although reported mortality remains low, there seems to be an increase in mortality in the past decade and urologists must remain vigilant of this.

International Alliance of Urolithiasis (IAU) guidelines on the metabolic evaluation and medical management of urolithiasis.

The aim of this study was to construct the fourth in a series of guidelines on the treatment of urolithiasis by the International Alliance of Urolithiasis (IAU) that by providing a clinical framework for the metabolic evaluation, prevention, and follow-up of patients with urolithiasis based on the best available published literature. All recommendations were summarized following a systematic review and assessment of the literature in the PubMed database from January 1976 to June 2022. Each generated recommendation was graded using a modified GRADE methodology. Guideline recommendations were developed that addressed the following topics: initial evaluation, metabolic testing, dietary measures, medical management, and follow-up of recurrent stone formers. It was emphasized by the Panel that prevention of new stone formation is as important as the surgical removal of the stones. Although general preventive measures may be effective in reducing stone recurrence rates in some patients, specific medical and dietary management should be well considered and eventually applied in an individualized manner based on the outcomes of metabolic work-up, stone analysis and some certain patient related factors. A detailed follow-up of each case is essential depending on the metabolic activity of each individual patient.

Efficacy of medical expulsive treatment with doxazosin in pediatric patients.

OBJECTIVE: To evaluate the possible efficacy of an α1 blocker (doxazosin) therapy on the management and disease course in pediatric patients with distal ureteral stones. MATERIALS AND METHODS: A total of 45 patients (24 boys and 21 girls) with a single lower ureteral stone were included in the study program. Their age range was 3-15 years (mean 6.65 ± 3.78). The children were randomized into 2 main groups: group 1 (n = 21), who received only ibuprofen 20 mg/kg/d divided into 2 equal doses for pain control during follow-up; and group 2 (n = 24), who received, in addition to ibuprofen, 0.03 mg/kg/d doxazosin once daily, before bed. RESULTS: The stone expulsion rate was 28.5% (6 of 21) in group 1 and 70.8% (17 of 24) in group 2 (P = .001). The number of daily colic attacks and stone expulsion time clearly demonstrated the advantage of doxazosin, with a statistically significant diminished number of pain attacks (P = .04) and shorter stone expulsion period (P = .001). Stones <5 mm were expulsed at greater rates than stones 5-10 mm in group 2 (P = .046). Also children aged <6 years passed the stones with significantly greater rates than children aged ≥7 years (P = .008). CONCLUSION: The use of α-adrenergic blocker agents could have certain advantages in attempts to render children stone free within a shorter period, which would inevitably diminish the number of colic attacks and the need for analgesic usage.

The effect of calcium channel blockers on stone regrowth and recurrence after shock wave lithotripsy.

We evaluated the possible effects of a calcium entry blocking agent "verapamil" on new stone formation and/or regrowth of residual fragments after shock wave lithotripsy (SWL) during long-term follow-up (>30 months) and compared the results with the success rates of adequate fluid intake. A total of 70 patients treated with SWL were randomly divided into three different groups, in the first two of which the patients received different preventive measures with respect to stone recurrence and/or regrowth. While 25 patients received a calcium channel blocking agent, verapamil hydrochloride, beginning 3 days before SWL and continued 4 weeks after the procedure, an additional 25 patients were put in an enforced fluid intake program and the remaining 20 patients received no specific medication and/or measure apart from close follow-up. Patients were followed regularly with respect to the clearance/regrowth of the residual fragments and that of new stone formation during long-term follow-up (within a mean follow-up of 30.4 months). The overall stone recurrence rate was 14% (10/70). Of the patients who became stone free (12/25, 48%) in group I, only one patient (1/12, 8.3%) showed a new stone formation during long-term follow-up. The figure was 40% (4/10) in group II patients and 55% (5/9) in group III patients receiving no specific medication. Regarding the residual stone fragments (<5 mm) after SWL, again high fluid intake was found to be the most effective on stone regrowth rates (2/13, 15.3%). Patients treated with verapamil also had acceptable regrowth rates (3/15, 20%). Finally, verapamil treatment significantly improved the clearance of residual fragments; while 7 out of 15 patients with residual fragments passed these particles successfully, (46.5%) in this group; these figures were 46% (6/13) and 18% (2/13) in the remaining groups. Residual fragments located in lower calyces demonstrated a poor clearance rate with higher regrowth rates. Verapamil administration was found to be effective enough to limit the regrowth of residual fragments and also to facilitate residual fragment clearance after SWL. Patients receiving this medication seemed to pass the retained fragments easily in a shorter time than the others.