Systemic vs. in-irrigation tranexamic acid in percutaneous nephrolithotomy: A systematic review, Bayesian network meta-analysis, and meta-regression.

INTRODUCTION: Percutaneous nephrolithotomy (PCNL) is the gold-standard treatment for large renal stones. One potentially significant complication of PCNL is blood loss, which can result in transfusion requirement and poorer stone-free outcomes. Tranexamic acid (TXA) has emerged as a promising intervention, administered systemically (TXA-S) or as part of irrigation fluid (TXA-I) in endourology. This study aimed to comprehensively analyze existing evidence regarding the applications of TXA in PCNL through a Bayesian network meta-analysis, offering insights into its efficacy and comparative effectiveness. METHODS: In February 2022, a PRISMA-compliant systematic review (PROSPERO registration number CRD42021270593) was performed to identify randomized controlled clinical trials (RCT) on TXA as either systemic therapy or in irrigation fluid. Studies in other languages other than English and Spanish were not considered. A Bayesian network was built using results from identified studies to create models that were later run through Markov Chain Monte Carlo sampling through 200000 iterations. RESULTS: Eight RCTs compared TXA-S vs. placebo, one TXA-I vs. placebo, and one TXA-I vs. TXA-S. TXA-I had lower risk of transfusion (relative risk [RR], 0.63 [0.47,0.84], SUCRA 0.950) than TXA-S (RR 0.79 [0.65,0.95], SUCRA 0.545). TXA-I had a lower risk of complications (RR 0.38 [0.21,0.67], SUCRA=0.957) compared to TXA-S (RR 0.55 [0.39, 0.78], SUCRA 0.539). TXA-I had a lower postoperative decrease in hemoglobin (MD -1.2 [1.3, 1.0], SUCRA 0.849) compared to TXA-S (MD-0.97 [-1.0, -0.93], SUCRA 0.646]). CONCLUSIONS: TXA, regardless of the route of administration, is an effective intervention in decreasing bleeding, postoperative complications, and risk of transfusion when compared with placebo. Further studies directly comparing TXA-S to TXA-I would be useful to determine the optimal route of delivery.

First analysis of the safety and efficacy of UGN-101 in the treatment of ureteral tumors.

OBJECTIVE: UGN-101 has been approved for the chemoablation of low-grade upper tract urothelial cancer (UTUC) involving the renal pelvis and calyces. Herein is the first reported cohort of patients with ureteral tumors treated with UGN-101. PATIENTS AND METHODS: We performed a retrospective review of patients treated with UGN-101 for UTUC at 15 high-volume academic and community centers focusing on outcomes of patients treated for ureteral disease. Patients received UGN-101 with either adjuvant or chemo-ablative intent. Response rates are reported for patients receiving chemo-ablative intent. Adverse outcomes were characterized with a focus on the rate of ureteral stenosis. RESULTS: In a cohort of 132 patients and 136 renal units, 47 cases had tumor involvement of the ureter, with 12 cases of ureteral tumor only (8.8%) and 35 cases of ureteral plus renal pelvic tumors (25.7%). Of the 23 patients with ureteral involvement who received UGN-101 induction with chemo-ablative intent, the complete response was 47.8%, which did not differ significantly from outcomes in patients without ureteral involvement. Fourteen patients (37.8%) with ureteral tumors had significant ureteral stenosis at first post-treatment evaluation, however, when excluding those with pre-existing hydronephrosis or ureteral stenosis, only 5.4% of patients developed new clinically significant stenosis. CONCLUSIONS: UGN-101 appears to be safe and may have similar efficacy in treating low-grade urothelial carcinoma of the ureter as compared to renal pelvic tumors.

Pharmacological Management of Ureteral Stent-related Symptoms: A Systematic Review, Bayesian Network Meta-analysis, and Meta-regression.

PURPOSE: Ureteral stents are commonly used for the treatment of ureteral obstruction, most often urolithiasis. Their use may be associated with significant bothersome symptoms and discomfort. Prior studies have examined the effects of various medication regimens on ureteral stent symptoms. This study utilized Bayesian network meta-analysis to analyze all available evidence on the pharmacological management of ureteral stent-related symptoms. MATERIALS AND METHODS: In December 2022 a systematic review was conducted following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines on randomized prospective studies on pharmacological management of ureteral stent-related symptoms reporting outcomes using the Ureteral Stent Symptom Questionnaire score on urinary symptoms and pain. The data were analyzed in Review Manager 5.3 and R Studio where a Bayesian network meta-analysis was performed. Treatments were ranked using surface under the cumulative ranking curve and mean difference vs placebo with 95% credible intervals. RESULTS: A total of 26 studies were analyzed. These were used to build networks which were modeled to run 100,000 Markov Chain Montecarlo simulations each. Drug-class analysis revealed the most effective class for each domain: for urinary symptoms, sexual performance, general health, and work performance-combined α-blocker and anticholinergic and phosphodiesterase 5 inhibitors; for pain-combined anticholinergic and pregabalin. The following were the most effective drugs and dosages for specific symptoms: for urinary symptoms-combined silodosin 8 mg+solifenacin 10 mg; for pain-combined silodosin 8 mg+solifenacin 10 mg; for sexual performance-tadalafil 5 mg. Combined silodosin 8 mg+solifenacin 10 mg+tadalafil 5 mg has the best general health scores while solifenacin 10 mg had the best work experience scores. CONCLUSIONS: This network meta-analysis demonstrated that the most effective drug therapy is different for each symptom domain. It is important to consider a patient's chief complaint and domains in order to ascertain the optimal medication regimen for each patient. Further iterations of this analysis can be strengthened by trials that directly compare more of these drugs instead of relying on indirect evidence.

Route of Administration for UGN-101 and Impact on Oncological and Safety Outcomes.

BACKGROUND: UGN-101 can be used for chemoablation of low-grade upper tract urothelial carcinoma (UTUC). The gel can be administered via a retrograde route through a ureteral catheter or an antegrade route via a nephrostomy tube. OBJECTIVE: To report outcomes of UGN-101 by route of administration. DESIGN, SETTING, AND PARTICIPANTS: We performed a retrospective review of 132 patients from 15 institutions who were treated with UGN-101 for low-grade UTUC via retrograde versus antegrade administration. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Survival outcomes are reported per patient. Treatment, complications, and recurrence outcomes are reported per renal unit. Statistical analysis was performed for primary endpoints of oncological response and ureteral stricture occurrence. RESULTS AND LIMITATIONS: A total of 136 renal units were evaluated, comprising 78 retrograde and 58 antegrade instillations. Median follow-up was 7.4 mo. There were 120 cases (91%) of biopsy-proven low-grade UTUC. Tumors were in the renal pelvis alone in 89 cases (65%), in the ureter alone in 12 cases (9%), and in both in 35 cases (26%). Seventy-six patients (56%) had residual disease before UGN-101 treatment. Chemoablation with UGN-101 was used in 50/78 (64%) retrograde cases and 26/58 (45%) antegrade cases. A complete response according to inspection and cytology was achieved in 31 (48%) retrograde and 30 (60%) antegrade renal units (p = 0.1). Clavien grade 3 ureteral stricture occurred in 21 retrograde cases (32%) and only six (12%) antegrade cases (p < 0.01). Limitations include treatment bias, as patients in the antegrade group were more likely to undergo endoscopic mechanical ablation before UGN-101 instillation. CONCLUSIONS: These preliminary results show a significantly lower rate of stricture occurrence with antegrade administration of UGN-101, with no apparent impact on oncological efficacy. PATIENT SUMMARY: We compared results for two different delivery routes for the drug UGN-101 for treatment of cancer in the upper urinary tract. For the antegrade route, a tube is inserted through the skin into the kidney. For the retrograde route, a catheter is inserted past the bladder into the upper urinary tract. Our results show a lower rate of narrowing of the ureter (the tube draining urine from the kidney into the bladder) using the antegrade route, with no difference in cancer control.

The ablative effect of mitomycin reverse thermal gel: Expanding the role for nephron preservation therapy in low grade upper tract urothelial carcinoma.

PURPOSE: Assess the real-world ablative effect of mitomycin reverse thermal gel for low-grade upper tract urothelial carcinoma (UTUC) in patients who undergo biopsy only or partial ablation and evaluate utility of complete ablation prior to UGN-101. MATERIAL AND METHODS: We retrospectively reviewed low-grade UTUC patients treated with UGN-101 from 15 high-volume centers. Patients were categorized based on initial endoscopic ablation (biopsy only, partial ablation, or complete ablation) and by size of remaining tumor (complete ablation, <1cm, 1-3cm, or >3cm) prior to UGN-101. The primary outcome was rendered disease free (RDF) rate at first post-UGN-101 ureteroscopy (URS), defined as complete response or partial response with minimal mechanical ablation to endoscopically clear the upper tract of visible disease. RESULTS: One hundred and sixteen patients were included for analysis after excluding those with high-grade disease. At first post-UGN-101 URS, there were no differences in RDF rates between those who at initial URS (pre-UGN-101) had complete ablation (RDF 77.0%), partial ablation (RDF 55.9%) or biopsy only (RDF 66.7%) (P = 0.14). Similarly, a complimentary analysis focusing on tumor size (completely ablated, <1cm, 1-3cm or >3cm) prior to UGN-101 induction did not demonstrate significant differences in RDF rates (P = 0.17). CONCLUSION: The results of the early real-world experience suggest that UGN-101 may play a role in initial chemo-ablative cytoreduction of larger volume low-grade tumors that may not initially appear to be amenable to renal preservation. Further studies will help to better quantify the chemo-ablative effect and to identify clinical factors for patient selection.

Infectious Complications, Healthcare Resource Use, and Medical Costs Associated with Delays in Percutaneous Nephrolithotomy Among Patients with Stone Disease and Ureteral Stent Placement.

Purpose: The relationship between ureteral stent duration before percutaneous nephrolithotomy (PCNL) and infectious complications, admissions, imaging, and medical costs was evaluated. Materials and Methods: Patients who underwent PCNL within 6 months of ureteral stent placement were identified from commercial claims, categorized by time to treatment (0-30, 31-60, and >60 days), and followed 1-month post-PCNL. The effect of delayed treatment on inpatient admissions, infectious complications (pyelonephritis/sepsis), and imaging utilization was evaluated with logistic regression. A generalized linear model evaluated the effect of delayed treatment on medical costs. Results: Among 564 patients with PCNL and meeting the inclusion criteria (mean age 50; 55% female; 45% from South), mean (standard deviation) time to surgery was 48.8 (41.8) days. Less than half (44.3%; n = 250) underwent PCNL within 30 days of ureteral stent placement, 27.0% (n = 152) between 31 and 60 days, and 28.7% (n = 162) >60 days. Time to PCNL was significantly associated with inpatient admissions (>60 vs ≤30 days odds ratio [OR] 1.97, 95% confidence interval [CI] 1.29-3.01, p = 0.0016), infectious complications (>60 vs ≤30 days OR 2.43, 95% CI 1.55-3.81, p = 0.0001), imaging utilization (31-60 vs ≤30 days OR 1.56, 95% CI 1.02-2.38, p = 0.0383; >60 vs ≤30 days OR 2.01, 95% CI 1.31-3.06, p = 0.0012), and medical costs (31-60 vs ≤30 days OR 1.27, 95% CI 1.08-1.49, p = 0.0048; >60 vs ≤30 days OR 1.46, 95% CI 1.24-1.71, p < 0.0001). Conclusions: Compared with PCNL within 30 days, patients undergoing PCNL >30 days after ureteral stent placement had increased likelihood of infectious complications, resource use, and medical costs. These results may inform health care resource utilization and PCNL prioritization.

The Fate of Residual Fragments After Percutaneous Nephrolithotomy: Results from the Endourologic Disease Group for Excellence Research Consortium.

Background: Residual fragments (RFs) after percutaneous nephrolithotomy (PCNL) have a significant impact on patients' quality of life and clinical course. There is a paucity of studies that evaluate the natural history of RFs after PCNL. The objective of this study is to compare rates of reintervention, complications, stone growth, and passage in patients with RFs >4, ≤4, and ≤2 mm after PCNL. Methods: Sites from the Endourologic Disease Group for Excellence (EDGE) research consortium examined data of PCNL patients from 2015 to 2019 with at least 1-year follow-up. RF passage, regrowth, reintervention, and complications were recorded and RFs were stratified into >4 and ≤4 mm groups, as well as >2 and ≤2 mm groups. Potential predictors for stone-related events after PCNL were determined using multivariable logistic regression analysis. It was hypothesized that larger RF thresholds would result in lower passage rates, faster regrowth, and greater clinically significant events (complications and reinterventions) than smaller RF thresholds. Results: A total of 439 patients with RFs >1 mm on CT postoperative day 1 were included in this study. For RFs >4 mm, rates of reintervention were found to be significantly higher and Kaplan-Meier curve analysis showed significantly higher rates of stone-related events. Passage and RF regrowth were not found to be significantly different compared with RFs ≤4 mm. However, RFs ≤2 mm had significantly higher rates of passage, and significantly lower rates of fragment regrowth (>1 mm), complications, and reintervention compared with RFs >2 mm. On multivariable analysis, older age, body mass index, and RF size were found to be predictive of stone-related events. Conclusions: With the largest cohort to date, this study by the EDGE research consortium further confirms that clinically insignificant residual fragment is problematic for patients after PCNL, particularly in older more obese patients with larger RFs. Our study underscores the importance of complete stone clearance post-PCNL and challenges the use of Clinically insignificant residual fragment (CIFR).

The why, who, how, and what of communicating CT radiation risks to patients and healthcare providers.

Computed tomography (CT) has witnessed tremendous growth in utilization. Despite its immense benefits, there is a growing concern from the general public and the medical community about the detrimental consequences of ionizing radiation from CT. Anxiety from the perceived risks associated with CT can deter referring physicians from ordering clinically indicated CT scans and patients from undergoing medically necessary exams. This article discusses various strategies for educating patients and healthcare providers on the benefits and risks of CT scanning and salient techniques for effective communication.

Understanding the ablation rate of Holmium:YAG and thulium fiber lasers. Perspectives from an in vitro study.

This study sought to analyze the ablation rates of Holmium:YAG (Ho:YAG) and thulium fiber laser (TFL) under different settings combinations. Lasering was carried out by a computed spiral pattern through a stepper motor bearing a laser fiber. BegoStones were placed inside a water container and lasered therein and the ablation rate was calculated. Different combinations were tested for ~12 Watts (W) for Ho:YAG and TFL lasers. Further 25 W combination for TFL were conducted testing higher frequencies. One-hundred-one experiments were conducted. Under ~12 W, the highest ablation rate for Ho:YAG was obtained with 40 Hz/0.3 J, and Virtual Basket™ (VB) emission mode [114.35 (88.30 - 126.40) mg/min] whereas for TFL, using 40 Hz/0.3 J, and long pulse [143.40 (137.40 - 146) mg/min]. A matched-comparison for 12 Hz/1 J settings showed that TFL outperformed Ho:YAG using medium pulse [63.30 (55.30 - 81.30) vs 132.00 (115.70 - 228.60) mg/min, p=0.016] and long pulse [62.90 (51.60 - 78.90) vs 134.70 (110.60 - 149.30) mg/min, p=0.016]. In the 40 Hz/0.3 J settings, TFL outperformed Ho:YAG (p=0.034). Nonetheless, Ho:YAG with VB's ablation rate increased [114.35 (88.30 - 126.40)], being comparable to that of TFL with medium pulse [127.5 (88.90 - 141.70)] (p=0.400). In TFL 25 W experiments, the ablation rate of 500 Hz / 0.05 J, was higher than those of 1000 Hz / 0.025 J (p=0.049). TFL ablation rate is higher than that of Ho:YAG. Moreover, the Virtual Basket™ emission mode, increased Ho:YAG ablation rates, resulting reaching similar to that of TFL in certain modalities.

Evaluation of fluid absorption during flexible ureteroscopy in an in vivo porcine model.

OBJECTIVE: To evaluate the relationship between renal pelvis pressure and fluid absorption during ureteroscopy (URS) in a live porcine model. MATERIALS AND METHODS: Flexible URS (fURS) was performed in anaesthetised female Yorkshire pigs. Prior to performing fURS, a 0.3556-mm (0.014″) pressure-sensing guidewire (Comet™, Boston Scientific) was placed to monitor renal pelvis pressure. A simulated fURS procedure was then performed for 1 h. Infusion of irrigation fluid (5% ethanol in saline) at target renal pelvis pressures (37-150 mmHg) was maintained for 1 h using a pressure bag and real-time feedback from the pressure-sensing guidewire. Venous blood was sampled every 10 min. The volume of irrigation fluid absorbed was estimated with established equations. RESULTS: A URS procedure was performed in vivo in 18 porcine kidneys and the volume of irrigation fluid absorbed during the 1 h URS was calculated. The mean (SD) volume of irrigation fluid absorbed after 1 h of simulated URS was 7.6 (5.7), 10.8 (7.1), 26.0 (15.8), and 56.8 (22.3) mL at renal pelvis pressures of 37, 55, 75, and 150 mmHg, respectively. Compared with URS with renal pelvis pressure of 37 mmHg, the volume of fluid absorption was significantly greater at renal pelvis pressures of 75 and 150 mmHg (P = 0.026 and P = 0.047, respectively). In addition, compared with URS with renal pelvis pressure of 37 mmHg, the rate of absorption was significantly greater at renal pelvis pressures of 75 and 150 mmHg (both P < 0.001). CONCLUSION: In this study of an in vivo porcine model of URS, increasing renal pelvis pressures during URS were associated with increases in irrigation fluid absorption and increases in the rate of fluid absorption.

Predicting Septic Shock After Emergent Ureteral Stenting in Stone-Related Obstruction and Presumed Infections.

Introduction: Systemic inflammatory response syndrome (SIRS) criteria have long been used to predict septic shock. The sequential organ failure assessment and quick sequential organ failure assessment (qSOFA) scores have been suggested to be more accurate predictors. This study aims to compare SIRS and qSOFA for predicting of septic shock in the setting of retrograde ureteral stenting for obstructing stones and concomitant urinary tract infection. Methods: A retrospective review of records at two centers of consecutive patients was performed. Patients with unilateral ureteral obstruction by a stone who underwent ureteral stent placement and suspicion of urinary tract infection were identified. Primary endpoints were SIRS and qSOFA positive scores, intensive care unit admission, and vasopressor requirements. Results: A total of 187 patients were included. SIRS criteria were met in 103 patients (55.1%) and in 30 patients who experienced septic shock. qSOFA criteria were met for 24 patients (12.8%) and in 18 patients who experienced septic shock. Specificity for postoperative septic shock was significantly higher for qSOFA than for SIRS criteria (75 vs 29.1%, McNemar test p < 0.001). Both SIRS and qSOFA had significant areas under the curve (AUC), qSOFA had a fair AUC of 0.750, p = 0.001, whereas SIRS had a poor AUC of 0.659, p = 0.008. Univariate logistic regression of SIRS and qSOFA for septic shock showed: qSOFA (odds ratio [OR] 46 [0.25-228], p = 0.001) and SIRS (OR 2.29 [0.716-7.37], p = 0.162). Conclusion: Although SIRS offers higher sensitivity, qSOFA score may offer advantages over SIRS criteria in evaluation of risk for septic shock for patients who present with obstructing ureteral stone and urinary tract infection.

The Uniform grading tooL for flexIble ureterorenoscoPes (TULIP-tool): a Delphi consensus project on standardised evaluation of flexible ureterorenoscopes.

OBJECTIVE: To develop a standardised tool to evaluate flexible ureterorenoscopes (fURS). MATERIALS AND METHODS: A three-stage consensus building approach based on the modified Delphi technique was performed under guidance of a steering group. First, scope- and user-related parameters used to evaluate fURS were identified through a systematic scoping review. Then, the main categories and subcategories were defined, and the expert panel was selected. Finally, a two-step modified Delphi consensus project was conducted to firstly obtain consensus on the relevance and exact definition of each (sub)category necessary to evaluate fURS, and secondly on the evaluation method (setting, used tools and unit of outcome) of those (sub)categories. Consensus was reached at a predefined threshold of 80% high agreement. RESULTS: The panel consisted of 30 experts in the field of endourology. The first step of the modified Delphi consensus project consisted of two questionnaires with a response rate of 97% (n = 29) for both. Consensus was reached for the relevance and definition of six main categories and 12 subcategories. The second step consisted of three questionnaires (response rate of 90%, 97% and 100%, respectively). Consensus was reached on the method of measurement for all (sub)categories. CONCLUSION: This modified Delphi consensus project reached consensus on a standardised grading tool for the evaluation of fURS - The Uniform grading tooL for flexIble ureterorenoscoPes (TULIP) tool. This is a first step in creating uniformity in this field of research to facilitate future comparison of outcomes of the functionality and handling of fURS.

Biomarkers in Urolithiasis.

A variety of biomarkers have been studied in the setting of conditions and scenarios related to kidney stone disease. These biomarkers are commonly serum markers, novel urinary proteins, and inflammatory whose use is aimed at providing clinicians with additional information of underlying processes and improving detection and stratification of patients with kidney stones, acute ureteral obstruction, stone passage, and related infectious complications. Their adoption has been limited, and further evidence is required to determine their role in the care of patients with stone disease.

Early experience with UGN-101 for the treatment of upper tract urothelial cancer - A multicenter evaluation of practice patterns and outcomes.

BACKGROUND: UGN-101 is a novel delivery system for intracavitary treatment of upper tract urothelial cancer (UTUC). UGN-101 was approved based on a pivotal trial for small volume residual low-grade UTUC. Our aim was to report our experience with UGN-101 in a more heterogenous and real-world setting. METHODS: We performed a retrospective review of all UGN-101 cases from 15 institutions with a focus on practice patterns, efficacy, and adverse effects. We include UGN-101 utilization in both the chemoablative and adjuvant setting. RESULTS: There were a total 136 renal units treated from 132 patients. The majority of cases were biopsy proven low-grade UTUC. Practice patterns varied considerably - the most common administration technique was antegrade instillation via a percutaneous nephrostomy. When utilized in the adjuvant setting, 69% of patients were disease free at the time of their first endoscopic evaluation, while in the chemoablative setting, 37% were endoscopically clear on the first evaluation (P < 0.001). Complete response was higher in patients with smaller tumor size prior to UGN-101 induction; low volume (<1 cm) residual disease was associated with a 70% complete response, similar to disease free rate at first endoscopic evaluation when UGN-101 was used in the adjuvant setting. The use of maintenance doses of UGN-101 was reported in 27% of cases. The overall incidence of new onset, clinically significant ureteral stenosis was 23%. CONCLUSIONS: This study represents the largest review of patients treated with UGN-101 and can serve as a basis of ongoing hypotheses regarding treatment with UGN-101 for UTUC.

Delays in Ureteroscopy and Shockwave Lithotripsy After Ureteral Stent Placement: Impact on Infectious Complications, Resource Use, and Medical Costs.

Purpose: To evaluate the effects of ureteral stent duration before ureteroscopy (URS) or extracorporeal shockwave lithotripsy (SWL) on infectious complications, health care resource utilization (HCRU), and costs. Materials and Methods: Patients who underwent URS/SWL within 6months of ureteral stent placement were identified from commercial claims, categorized by time from stent placement to URS (0-15, 16-30, 31-60, and >60 days) or SWL (0-15, 16-30, and >30 days), and followed 1-month postprocedure. The relationship between ureteral stent duration and emergency department (ED) visits, inpatient admissions, infectious complications (pyelonephritis/sepsis), imaging, and costs was evaluated. Results: Mean time to URS (n = 9276 patients) was 21.3 ± 24.4 days and SWL (n = 4689 patients) was 19.0 ± 24.8 days. Compared with patients who underwent URS within 15 days of ureteral stent placement, URS 31 to 60 days after ureteral stent placement was significantly associated with inpatient admissions (odds ratio [OR] 2.56, 95% confidence interval [CI] 2.03-3.22); infectious complications (OR 2.82, 95% CI 2.09-3.81); imaging (OR 2.12, 95% CI 1.82-2.46); and medical costs (OR 1.49, 95% CI 1.40-1.58). Compared with patients who underwent SWL within 15 days of ureteral stent placement, SWL more than 30 days after ureteral stent placement was significantly associated with ED visits (OR 1.79, 95% CI 1.37-2.34); inpatient admissions (OR 3.34, 95% CI 2.38-4.69); infectious complications (OR 3.54, 95% CI 2.20-5.70); imaging (OR 2.65, 95% CI 2.23-3.15); and medical costs (OR 1.45, 95% CI 1.36-1.54). Conclusions: URS or SWL >30 days after ureteral stent placement increased the likelihood of infectious complications, HCRU, and medical costs.

New Generation Pulse Modulation in Holmium:YAG Lasers: A Systematic Review of the Literature and Meta-Analysis.

(1) Background: New pulse modulation (PM) technologies in Holmium:YAG lasers are available for urinary stone treatment, but little is known about them. We aim to systematically evaluate the published evidence in terms of their lithotripsy performance. (2) Methods: A systematic electronic search was performed (MEDLINE, Scopus, and Cochrane databases). We included all relevant publications, including randomized controlled trials, non-randomized comparative and non-comparative studies, and in-vitro studies investigating Holmium:YAG lithotripsy performance employing any new PM. (3) Results: Initial search yielded 203 studies; 24 studies were included after selection: 15 in-vitro, 9 in-vivo. 10 In-vitro compared Moses with regular PM, 1 compared Quanta's, 1 Dornier MedTech's, 2 Moses with super Thulium Fiber Laser, and 1 compared Moses with Quanta PMs. Six out of seven comparative studies found a statistically significant difference in favor of new-generation PM technologies in terms of operative time and five out of six in fragmentation time; two studies evaluated retropulsion, both in favor of new-generation PM. There were no statistically significant differences regarding stone-free rate, lasing and operative time, and complications between Moses and regular PM when data were meta-analyzed. (4) Conclusions: Moses PM seems to have better lithotripsy performance than regular modes in in-vitro studies, but there are still some doubts about its in-vivo results. Little is known about the other PMs. Although some results favor Quanta PMs, further studies are needed.