Ureteral Access Sheath Placement Research Articles

The relationship between the force applied and perceived by the surgeon during ureteral access sheath placement: ex-vivo experimental model

PurposeTo define a peak force of insertion (PFOI) threshold for ureteral damage during ureteral access sheath (UAS) placement on an experimental ureteral orifice model.MethodsA 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”.ResultsUsing 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).ConclusionThe 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.

The safety and efficacy of Sotn ureteroscopy for renal and upper ureteral calculi: a prospective multicenter randomized controlled trial.

Sotn ureteroscopy is a new lithotripsy procedure developed on the basis of ureteroscopy and includes a rigid ureteral access sheath, standard mirror, lithotripsy mirror, and Sotn perfusion aspirator. Thus, we performed a prospective multicenter randomized controlled trial comparing the safety and efficacy of Sotn ureteroscopy in the treatment of renal and upper ureteral calculi. In this study, 224 patients with renal and upper ureteral calculi were randomly divided equally into study and control groups from March 2018 to March 2022. All the patients were approved by the hospital ethics committee (proof number: ZF-2018-164-01 and ZF-2018-165-01) of the Second Affiliate Hospital of Guangzhou University of Chinese Medicine in China. The primary outcome was stone-free rate (SFR) assessed by computed tomography on the 1st day and month after treatment and operation duration. The secondary outcome was postoperative complication rate. In total, for upper ureteral calculi, the SFR of 1 day after operation of the Sotn ureteroscopy group was significantly higher than the rigid ureteroscopy group (83.6% vs. 60%, P=0.006). Moreover, operative time (33.7±1.80 vs. 52.9±2.73 min, P<0.005) of the Sotn ureteroscopy group was significantly lower than the rigid ureteroscopy group. Additionally, the SFR of 1 day after operation and operative time for the study group (Sotn ureteroscopy combined with flexible ureteroscopy) and the control group (flexible ureteroscopy alone) were 63.2% and 36.8% (P=0.005), 65.6±4.06 and 80.3±4.91 (P=0.023), respectively. However, there were no significant differences in the SFR of 1 month after operation, success rate of ureteral access sheath placement, and postoperative complications between the two groups (P>0.05). In subgroups with stone diameters ≥1.5 cm and stone CT values ≥1000 Hounsfield units, Sotn ureteroscopy showed more advantages in terms of the SFR of 1 day after operation. Importantly, complications such as ureteral injury, sepsis, fever, and severe hematuria were not statistically different between the two groups (P>0.05). For renal and upper ureteral calculi, Sotn ureteroscopy has the advantage of a higher SFR of 1 day after the operation and a shorter operative time, suggesting that the Sotn ureteroscopy may have further potential applications in clinics.

“Rule of Five” in Ureteral Dilatation and its Role in Ureteral Access Sheath Placement during Retrograde Intrarenal Surgery

Purpose: Sequential ureteral dilatation facilitates placement of ureteral access sheath during retrograde intrarenal surgery. The authors adopted some improvisations in conventional sequential ureteral dilatation methods to achieve improved ureteral accommodation and prefer to call the sequential ureteral dilatation performed with these improvisations as “Rule of five” (ROF) ureteral dilatation. The objective of the article was to describe the “ROF” ureteral dilatation technique and share the preliminary experience with the technique. Materials and Methods: “ROF” ureteral dilatation involves repetitive dilatation of ureter for five times by 10 Fr ureteral dilator, with each dilatation lasting for 5 s. The technique was used in patients who underwent retrograde intrarenal surgery for renal calculi and in whom 12 Fr ureteral dilator passage and 9.5/11.5 Fr ureteral access sheath placement was not possible by conventional sequential ureteral dilatation methods. Preliminary efficacy and safety outcomes were reported. Results: “ROF” ureteral dilatation was performed in 14 renal units. Ureteral access sheath placement was successful in 10 renal units (71.4%) and unsuccessful in 4 renal units (28.6%). Ureteral access sheath associated low-grade ureteral wall injury was noted in 2 renal units (14.3%). None had new onset hydroureteronephrosis in follow-up ultrasonography and all patients were asymptomatic in the follow-up period. Conclusion: “ROF” ureteral dilatation is an improvisation of conventional sequential ureteral dilatation. It facilitates successful and safe ureteral access sheath placement in a proportion of patients undergoing sequential ureteral dilatation.

Identification of the Risk Factors for the Failure of Ureteral Access Sheath Placement.

Purpose Insertion of a ureteral access sheath (UAS) may fail in some patients in retrograde intrarenal surgery (RIRS), and this study aimed to seek preoperative risk factors for the failure of 12/14F UAS placement. Methods We retrospectively analyzed 260 consecutive patients who underwent RIRS between May 2020 and March 2022 at our institution. Data on patient and stone characteristics and several computed tomography (CT)-based measurements were collected and compared between the success and failure UAS placement groups. Results Twenty-nine (11.2%) patients failed to insert the UAS. Age, gender, height, weight, stone side, stone location, length of history, and computed tomography (CT)-based parameters were not significant differences between the two groups. Univariate logistic regression analyses showed sex (female/male) (odds ratio: 0.287 and 95% CI [0.107, 0.722], p=0.013), length of history 15–31 days (odds ratio: 0.315 and 95% CI [0.102, 0.974], p=0.045), length of history >31 days (odds ratio: 0.202 and 95% CI [0.051, 0.805], p=0.023), and diameter of the ipsilateral common iliac artery (odds ratio: 1.285 and 95% CI [1.018, 1.623], p=0.035) were associated with UAS placement. Conclusion Our study indicated that males, the short length of history, and the short diameter of the ipsilateral common iliac artery were the risk factors for the failure of UAS placement.

Safety and efficacy of sequential balloon dilation prior to ureteral access sheath insertion in nonstented patients undergoing ureteroscopy

Techniques such as ureteral access sheath placement and balloon dilation are utilized to facilitate ureteroscopy. A retrospective review was performed to evaluate the efficacy and complications from ureteral access sheath (UAS) placement with or without sequential ureteral balloon dilation (SBD) in non-prestented patients who underwent ureteroscopy with UAS with or without SBD for renal or proximal ureteral stones from February 2014 to April 2017. This was a two-surgeon series of 124 patients divided into groups of SBD + UAS or direct UAS placement. Postoperative complications included hematuria, fever, and flank pain. Successful UAS insertion rates and postoperative complication rates were statistically significantly higher in the SBD + UAS group (P = 0.01 and 0.023, respectively). The procedure time, emergency department return, and 6-week stone-free rates were not statistically different between the groups. In conclusion, SBD + UAS has a higher success rate of UAS insertion compared to direct UAS alone, allowing for same-setting ureteroscopy. However, SBD + UAS is associated with significantly higher rates of fever, flank pain, and hematuria. We conclude that SBD + UAS and direct UAS are equivalent.

Real-world Global Outcomes of Retrograde Intrarenal Surgery in Anomalous Kidneys: A High Volume International Multicenter Study

ObjectiveTo analyze the trends and outcomes of retrograde intrarenal surgery for treatment of urolithiasis in anomalous kidneys in a large international multicenter series. Materials and MethodsWe designed a multicentric retrospective study. Nineteen high-volume centers worldwide were included. Pre-, peri- and postoperative data were collected, and a subgroup analysis was performed according to renal anomaly. ResultsWe analyzed 414 procedures: 119 (28.7%) were horseshoe kidneys, 102 (24.6%) pelvic ectopic kidneys, 69 (16.7%) malrotated kidneys and 50 (12.1%) diverticular calculus. The average size (SD) of the stone was 13.9 (±6) millimeters and 193 (46.6%) patients had a pre-operative stent. In 249 cases (60.1%) a disposable scope was used. A UAS (ureteral access sheath) was used in 373 (90%) patients. A Holmium laser was used in 391 (94.4%) patients. The average (SD) operating time was 65.3 (±24.2) minutes. Hematuria, caliceal perforation and difficulty in stone localisation were mostly seen in diverticular stones and difficulty in UAS placement and lithotripsy in the cases of renal malrotation. The overall complication rate was 12%. Global stone-free rate was 79.2%. Residual fragments (RF) were significantly lesser in the pre-stented group (P <.05). Diverticular calculi was the group with more RF and needed ancillary procedures (P <.05). ConclusionRetrograde intrarenal surgery in patients with anomalous kidneys is safe and effective with a high single-stage stone-free rate and low complication rate. There is a trend toward using smaller and disposable scopes and smaller UAS. Diverticular stones can still be challenging with higher rates of intraoperative hematuria, caliceal perforation and RF.

Comparison of the Efficacy of ShuoTong Ureteroscopy and Simple Flexible Ureteroscopy in the Treatment of Unilateral Upper Ureteral Calculi.

Background: ShuoTong ureteroscopy (Sotn-ureteroscopy, ST-URS), a new lithotripsy operation method developed on the basis of ureteroscopy, is widely used to treat ureteral stones in China. Its composition includes rigid ureteral access sheath, standard mirror, lithotripsy mirror, and ShuoTong perfusion aspirator (ST-APM). Here, we compared the efficacy and safety of the ST-URS and the flexible ureteroscope (F-URS) holmium laser lithotripsy in the treatment of unilateral upper ureteral calculi.Methods: Retrospective analysis was conducted on the clinical data of 280 patients who met the inclusion 1) urinary tract CT was diagnosed with unilateral single upper ureteral calculi above the L4 lumbar spine; 2) patient age was from 18 to 80 years old; 3) patients were informed and consented to this study; and 4) patients were approved by the hospital ethics committee (proof number: KY-2019-020) and the exclusion criteria for unilateral upper ureteral calculi in the First Affiliated Hospital of Xiamen University from January 2018 to November 2020, and they were divided into the ST-URS group and the flexible ureteroscopy (F-URS) group.Results: The stone-free rate of 1 day after operation of the ST-URS group was significantly higher than the F-URS group (63.71 vs. 34.62%, P < 0.0001). The operative time (38.45 vs. 46.18 min, P = 0.005) and hospitalization cost (27,203 vs. 33,220 Yuan, P < 0.0001) of the ST-URS group were significantly lower than the F-URS group. There were no significant differences in the success rate of ureteral access sheath placement, operative blood loss, stone-free rate of 1 month after operation, postoperative complications, postoperative hospital stay, and postoperative visual analog scale (VAS) pain score between the two groups (P > 0.05). In subgroups of a diameter of calculi ≥ 1.5 cm, calculi CT numerical value ≥ 1,000 Hounsfield unit and the preoperative hydronephrosis range ≥ 3.0 cm, ST-URS shows more advantages in the operative time, stone-free rate of 1 day after the operation, the hospitalization cost, and the incidence of postoperative complications.Conclusion: In unilateral upper ureteral stones treated with a holmium laser, compared with the simple F-URS, the ST-URS has a shorter operative time, lower hospitalization cost, and a higher stone-free rate of 1 day after the operation, suggesting that the ST-URS could be more widely applied in clinics.

The effect of preoperative tamsulosin on ureteroscopic access in school-aged children

Flexible ureteroscopes are not tailored for pediatric ureteral size and may not pass at first attempt into the pediatric ureter. Administration of tamsulosin preoperatively in adults has been shown to facilitate ureteral access sheath placement. Several studies have shown tamsulosin to be safe and effective when utilized for medical expulsive therapy in pediatric patients, but its utility for preoperative ureteral dilation has not been studied to date. We hypothesized that preoperative tamsulosin reduces failed ureteroscopic access in children. We conducted a retrospective review of patients aged 0-18 years undergoing flexible ureteroscopy (URS) from 2014 to 2019at a single institution. Patients were divided into those taking 0.4mg of tamsulosin daily for at least 1 week prior to surgery and those not taking tamsulosin. The primary outcome was failure to pass a 7.95 Fr flexible ureteroscope on initial attempt, requiring stent placement and staged management. Patients undergoing URS or stent placement within the prior year, requiring semi-rigid URS, or with genitourinary anomalies were excluded. A total of 49 patients met inclusion criteria. The tamsulosin group (n=13) and non-tamsulosin group (n=36) were similar with respect to demographic data. The percentage of prepubertal patients was 53% vs 33% (p=0.19). The tamsulosin group had lower failed URS (38% vs 61%, p=0.20). When stratified by age, both prepubertal and postpubertal patients in the tamsulosin group had lower failed URS (43% vs 67%, p=0.67 and 33% vs 58%, p=0.38). These clinically significant results suggest initial passage of a flexible ureteroscope is more successful in pediatric patients on preoperative tamsulosin. This study was largely limited by its low power and flaws inherent to its retrospective design. Our results have implications for prescribing tamsulosin preoperatively to reduce multiple procedures and anesthetics in children. Adequately powered prospective trials are warranted to confirm preoperative tamsulosin reduces failed first-attempt flexible URS in children.

Pre-stenting for Retrograde Intrarenal Surgery: Need and Duration: a Prospective Randomized Clinical Study

Introduction: To evaluate if retrograde intrarenal surgery with ureteral access sheath requires prestenting. In case pre-stenting becomes an option, how long does it need to be stented. &#x0D; Materials and Methods: After obtaining approval from Institutional Review Board and informed consent, a prospective randomized controlled study was conducted in the Department of Urology, Bir Hospital for 18 months. All the patients enrolled for retrograde intrarenal surgery were grouped into 3 groups: Group 1 – without pre-stenting, Group 2 – one week of pre-stenting, and Group 3 – two weeks of pre-stenting. Success was defi ned as an ability to accommodate a 10/12 F ureteral access sheath during retrograde intrarenal surgery. Ureteral access sheath induced ureteric wall injury was also taken into consideration.Results: Among 179 cases, 152 cases were included in the study. In 36 patients out of 53 (67.92%) in group 1, 10/12 F ureteral access sheath was negotiable without pre-stenting, marking the frequency of distensible ureters. In 44 patients out of 47 (93.66%) from group 2 and all 52 patients (100%) from group 3, ureteral access sheath placement was successful after one and two weeks of pre-stenting respectively. Ureteric wall injury of grade1 and 2, was found in 9 patients (5.9%).Conclusions: The majority of ureters (67.92%) are distensible, not requiring pre-stenting before retrograde intrarenal surgery. One and two weeks of pre-stenting carries a success rate of 93.66% and 100% respectively.

An Early Experience of Retrograde Intrarenal Surgery (RIRS) in National Institute of Kidney Diseases and Urology

Background: Advancements in the endoscopic armamentarium, retrograde intrarenal surgery has become a viable and attractive option for the treatment of renal stones because of its high stone-free rates (SFRs) and low morbidity.&#x0D; Objective: To describe our experience and outcome of RIRS for the treatment of renal stones and to assess its effectiveness and safety.&#x0D; Design, setting, and participants: A retrospective analysis of 60 patients who underwent RIRS for renal stones at our institute between January 2018 to December 2018 was performed.&#x0D; Surgical procedure: Flexible ureteroscopy and laser lithotripsy using a standardized technique with last-generation flexible ureteroscopes (Flex-Xc) using Holmium-YAG laser.&#x0D; Outcome measurements and statistical analysis: Clinical data were collected and intraoperative and postoperative outcomes were assessed (Ureteral access sheath placement, operation time, hospital stay, stone free rate, post-operative blood transfusion &amp; fever, need for second session of RIRS. A descriptive statistical analysis was performed.&#x0D; Results and limitations: The mean overall stone size was 13±3 mm. Pre stenting done in all cases. Ureteral access sheath placement was possible in 54(90%) patients. At 1 month follow-up, the overall primary SFR was 86.67%(52 cases), the secondary SFR was 96.67%(58 cases).The mean operative time was 91.96±18.7 min. Mean hospital stay was 1.86±1.02 days. Complications were reported in 8 (13.33%) patients overall, with fever in 6 patients (10%), steinstrasse in 2(3.33%) patients need for second session RIRS in 6 patients (10%).No patient needed blood transfusion. The main limitation of the study is the retrospective nature.&#x0D; Conclusions: RIRS performed using a flexible ureterorenoscope marked the beginning of a new era in urology. It is safe and effective procedure and an alternative to extracorporeal shock wave lithotripsy (ESWL) and Percutaneous nephrolithotomy (PCNL) in the treatment of selected renal stones.&#x0D; Bangladesh Journal of Urology, Vol. 23, No. 1, January 2020 p.3-10

PD34-04 URETEROSCOPIC PERFORMANCE OF THULIUM FIBER LASER (SOLTIVE PREMIUM SUPER PULSED LASER TM ) FOR THE TREATMENT OF UROLITHIASIS: RESULTS OF THE FIRST CASE SERIES IN THE UNITED STATES

You have accessJournal of UrologyStone Disease: Surgical Therapy V (PD34)1 Apr 2020PD34-04 URETEROSCOPIC PERFORMANCE OF THULIUM FIBER LASER (SOLTIVE PREMIUM SUPER PULSED LASERTM) FOR THE TREATMENT OF UROLITHIASIS: RESULTS OF THE FIRST CASE SERIES IN THE UNITED STATES Raphael Carrera*, Joseph Randall, Maurilio Garcia-Gil, Bodo Knudsen, Ben Chew, Jeffrey Thompson, Mitchell Humphreys, and Wilson Molina Raphael Carrera*Raphael Carrera* More articles by this author , Joseph RandallJoseph Randall More articles by this author , Maurilio Garcia-GilMaurilio Garcia-Gil More articles by this author , Bodo KnudsenBodo Knudsen More articles by this author , Ben ChewBen Chew More articles by this author , Jeffrey ThompsonJeffrey Thompson More articles by this author , Mitchell HumphreysMitchell Humphreys More articles by this author , and Wilson MolinaWilson Molina More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000905.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Ureteroscopy with laser lithotripsy is commonly used in the treatment of urolithiasis. Recent in vitro studies demonstrate efficacy of the Thulium Fiber Laser (SOLTIVE Premium Super Pulsed LaserTM) during lithotripsy and a safety profile comparable to Ho:YAG systems. SOLTIVE has the advantages of smaller fiber compatibility and higher frequency dusting settings. In this study we report the first case series of ureterorenoscopy in the United States using the Thulium Fiber Laser for the treatment of upper urinary tract stones. METHODS: After Institutional Review Board approval, a multicentric retrospective chart review of patients treated with the Thulium Fiber Laser from 10/8/19 to 10/24/19 was conducted. Basic demographic information, pre-operative, and peri-operative data were recorded. RESULTS: 25 patients were included with a median age of 53 years (range 27-82). 39 stones were treated including 12 within the ureter, 13 in the lower pole, 13 in mid or upper poles, and 1 staghorn calculus. Median diameter for the largest stone in each patient was 9 mm (range 4-50 mm) and median Hounsfield units were 900 (range 480-1750). Both the 150 and 200 nm fibers were used with a mean laser time of 12 minutes and mean total energy of 17.1 J. Dusting technique was commonly used with pulse frequencies up to 500 Hz (table 1). Median operative time was 52 minutes. Calcium oxalate dihydrate was the most common stone composition, followed by calcium phosphate and calcium oxalate monohydrate. Complications were limited to two endoscopic grade 1 ureteral injuries related to ureteral access sheath placement, one case of renal collecting system bleeding that was adequately managed with laser coagulation settings, and one case of postoperative sepsis. All but 3 patients were discharged on their day of surgery. CONCLUSIONS: This initial case series in the United States of the Thulium Fiber Laser is promising for the treatment of urolithiasis. Sub-200 nm fibers and dusting settings up to 500 Hz were utilized successfully. No specific complications related to use of the laser were seen. Follow up with stone-free rates, larger multicentric case series, and randomized clinical trials are needed to demonstrate the efficacy of this laser. Source of Funding: None © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e712-e713 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Raphael Carrera* More articles by this author Joseph Randall More articles by this author Maurilio Garcia-Gil More articles by this author Bodo Knudsen More articles by this author Ben Chew More articles by this author Jeffrey Thompson More articles by this author Mitchell Humphreys More articles by this author Wilson Molina More articles by this author Expand All Advertisement PDF downloadLoading ...

MP69-16 PROSPECTIVE EVALUATION OF BILATERAL RIRS: IS IT REALLY SAFE?

You have accessJournal of UrologyStone Disease: Surgical Therapy VII (MP69)1 Apr 2020MP69-16 PROSPECTIVE EVALUATION OF BILATERAL RIRS: IS IT REALLY SAFE? Alexandre Danilovic*, Fabio Torricelli, Giovanni Marchini, Carlos Batagello, Fabio Vicentini, Olivier Traxer, Miguel Srougi, William Nahas, and Eduardo Mazzucchi Alexandre Danilovic*Alexandre Danilovic* More articles by this author , Fabio TorricelliFabio Torricelli More articles by this author , Giovanni MarchiniGiovanni Marchini More articles by this author , Carlos BatagelloCarlos Batagello More articles by this author , Fabio VicentiniFabio Vicentini More articles by this author , Olivier TraxerOlivier Traxer More articles by this author , Miguel SrougiMiguel Srougi More articles by this author , William NahasWilliam Nahas More articles by this author , and Eduardo MazzucchiEduardo Mazzucchi More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000949.016AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Bilateral same session procedures are appealing for economic reasons and are deemed to be convenient for the patient. However, there is no prospective study to evaluate the outcomes of bilateral same session retrograde intrarenal surgery (RIRS). The aim of this study was to prospectively compare the outcomes of bilateral same session RIRS to unilateral RIRS and to compare the outcomes of first to second operated kidney in bilateral same session RIRS. METHODS: Consecutive symptomatic adult patients with kidney stones up to 20 mm that accepted to be treated by RIRS in our Institution from August 2016 to August 2017 were prospectively studied. Stone free rate was evaluated on POD 90 non-contrast CT for each renal unit. Surgical complications based on Clavien-Dindo classification during the 90 days of follow-up were recorded. Outcomes of bilateral same session RIRS were compared to unilateral RIRS. Outcomes of first operated kidney were compared to second operated kidney in bilateral same session RIRS group. RESULTS: Failure in ureteral access sheath placement occurred in 5/74 (6.8%) renal units of planned unilateral RIRS and in 7/54 (13.0%) renal units of planned bilateral RIRS (p=0.234). Sixty-nine patients were evaluated in the unilateral RIRS group and 23 patients with 46 renal units in the bilateral same session RIRS group. Clinical features of unilateral RIRS vs. bilateral RIRS were compared in Table 1. Demographic data and stone characteristics were similar between groups. Outcomes of unilateral RIRS and bilateral same session RIRS were compared in Table 2. Stone free rates were similar between bilateral and unilateral RIRS with less consumption of disposable devices in bilateral group. However, bilateral group had higher complication rate, higher frequency of emergency room visits and higher creatinine during follow-up. First operated kidney outcomes were similar to second operated kidney of bilateral same session RIRS (Table 3). CONCLUSIONS: Although bilateral same session RIRS had similar stone free rate and used less disposable devices compared to unilateral RIRS, we can not recommend as a standard practice because bilateral same session RIRS had higher overall complication rate, higher frequency of emergency room visits and higher creatinine during follow-up. There was no significant outcome difference between first and second operated kidney in bilateral RIRS. Source of Funding: FAPESP 2014/05130-2 © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e1051-e1052 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Alexandre Danilovic* More articles by this author Fabio Torricelli More articles by this author Giovanni Marchini More articles by this author Carlos Batagello More articles by this author Fabio Vicentini More articles by this author Olivier Traxer More articles by this author Miguel Srougi More articles by this author William Nahas More articles by this author Eduardo Mazzucchi More articles by this author Expand All Advertisement PDF downloadLoading ...

Controversies associated with ureteral access sheath placement during ureteroscopy.

The use of ureteral access sheaths (UAS) is common practice during routine flexible ureteroscopy procedures. However, debates and concerns continue amongst endourologists on routine UAS placement. UAS placement allows for multiple passages of the ureteroscope, decreases intrarenal pressure, and may improve stone-free rates. However, concerns for the UAS's effectiveness in these claimed benefits and complications related to UAS placement has been documented and investigated by many. In this review, we will discuss the controversies surrounding the placement of UAS during ureteroscopy.

Can mirabegron facilitate ureteral access sheath placement during flexible ureterorenoscopy?

Can mirabegron facilitate ureteral access sheath placement during flexible ureterorenoscopy?

MP17-02 URETERAL STRICTURE FORMATION AFTER USE OF URETERAL ACCESS SHEATH – 4 YEAR FOLLOW-UP DATA

INTRODUCTION AND OBJECTIVES:Recent studies have described ureteral lesions caused by placement of ureteral access sheaths during ureteroscopy. However, the long-term sequelae of these lesions is un...

A Prospective Study Analyzing the Association Between High-grade Ureteral Access Sheath Injuries and the Formation of Ureteral Strictures

ObjectiveTo assess the intermediate- and long-term effect of high-grade ureteral injuries from ureteral access sheaths. MethodsPatients undergoing ureteroscopy for upper tract calculi were prospectively enrolled at 2 sites from 2010 to 2015. A 12/14 French sheath was used and the ureter was inspected with a flexible ureteroscope during withdrawal of the sheath and recorded. The videos were then evaluated by 2 blinded endourologists, and any injuries were graded per the Traxer ureteral injury scale. Only high-grade injuries were included. The primary endpoint was defined as ongoing hydronephrosis without an obstructing stone on follow-up imaging indicating a ureteral stricture. Logistic regression analysis was used to assess the relationship between hydronephrosis, ureteral injury, and other patient variables. ResultsFifty-six patients were identified with high-grade ureteral injuries. Sixteen patients (28.6%) were female. Median age was 56.4 years (range 14-85). Median follow-up was 35.8 months (range 0-88). Three patients (5.5%) had hydronephrosis on follow-up imaging, only 1 of whom developed a de novo ureteral stricture. On univariate analysis, hydronephrosis was associated with a shorter stent duration (P = .11) and older age (P = .17). ConclusionEndoscopically identified high-grade ureteral lesions following ureteral access sheath placement do not lead to clinically significant sequelae on intermediate term follow-up, with a stricture rate comparable to those without visible injuries of 1.8%.

Can alpha blockers facilitate the placement of ureteral access sheaths in retrograde intrarenal surgery?

To investigate the effects of alpha blocker treatment on the placement of ureteral access sheaths (UAS) during retrograde intrarenal surgery (RIRS). This study was a retrospective analysis of prospectively collected data. Patients who underwent RIRS due to renal stones between November 2015 and December 2017 were seperated into two groups. Age, gender, body mass index (BMI), stone size, laterality, hydronephrosis degree, and renal stone density were recorded. Tamsulosin (0.4 mg/day) was prescribed to the study group (n=25) 2 weeks before the operation. The control group (n=25) underwent the operation without any additional treatment. All the operations were performed using a 7.5 Fr flexible ureteroscope and 9.5/11.5 Fr (Cook, Blooming, USA) UAS. Two patients in the study group were excluded from the study as they suffered from dizziness and retrograde ejaculation. No statistically significant difference was found between the patients in the study group (n=23) and control group (n=25) in terms of age, gender, BMI, stone size, laterality, hydronephrosis, and renal stone density (p=0.470, p=0.536, p=0.456, p=0.102, p=0.555, p=0.732, and p=0.317, respectively). The UAS could be successfully placed on the first attempt in 15 (65.2%) patients in the study group and 11 (44%) patients in the control group during the first attempt itself. Even though the successful UAS placement rate was higher in the study group, no statistically significant values were observed (p=0.141). The data obtained from the present study showed that the use of alpha blockers prior to RIRS did not improve the UAS placement rates. It is considered that studies conducted on more patients might be able to achieve significant values.

Efficacy and Safety of Ultrasonic Longitudinal-Axis Vibration for the Reduction of Ureteral Access Sheath Insertion Force: A Randomized Controlled Trial in a Porcine Model.

Excessive bulking force during ureteral access sheath (UAS) placement may induce injury. The sliding friction between surfaces can be reduced with the application of ultrasonic vibration. We investigated the efficacy and safety of an ultrasonic vibration transducing device for reducing the maximal ureteral access sheath insertion force (UASIF). A device was developed for transducing ultrasonic longitudinal-axis vibration onto the UAS at an adjustable amplitude and frequency while measuring the degree of UASIF. In the pilot study, six porcine models were used to investigate the optimal amplitude and frequency of vibration and to calculate sample size. Twelve porcine models were utilized in a randomized controlled trial. Resected ureters were pathologically evaluated for ureteral injury. The transduction of ultrasonic vibration at an amplitude of 0.04 g and a frequency of 18,000 Hz resulted in a maximal UASIF reduction of 36.4% (interquartile range 32.7-43.1). Maximal UASIF tended to decrease with increasing vibration frequency. No significant differences in UASIF reductions were observed according to amplitude. In the randomized controlled trial, the maximal UASIF reduction was 37.0% (interquartile range 21.4-44.2). Grade II injury was pathologically diagnosed in 8.3% (1/12) of the ureters in both groups. The transduction of ultrasonic longitudinal-axis vibration onto the UAS reduces maximal UASIF and does not harm the ureter. Reducing the velocity of sheath insertion may further reduce maximal UASIF.

The effect of ureteral stenting before flexible ureteroscopic lithotripsy: a Meta-analysis

Purpose To evaluated the effect of ureteral stent placement before flexible ureteroscopic lithotripsy(FURL). Methods A systematic search of PubMed, Cochrane Library, Embase, Scopus, VIP, CNKI, Wanfang database from databases establishment to February 2017 was performed to identify all clinical trials on the effect of ureteral stenting before flexible ureteroscopic lithotripsy. The outcomes included stone-free rate, mean operative time, success rate of ureteral access sheath placement and postoperative complications. RevMan 5.3 software was used to complete the Meta statistical analysis. Results Three randomized and four non-randomized studies were analyzed, which consisted of 1 176 patients including 788 cases in experimental group , 388 cases in control group. Meta-analysis showed significant differences between experimental group and control group in stone-free rate(OR=1.88, 95%CI 1.30-2.71, P<0.001). There was no statistically significant difference in mean operative time between experimental group and control group(WMD=-0.99, 95%CI -10.63-8.65, P=0.84). The success rate of ureteral access sheath placement was significantly higher in experimental group than that in the control group(OR=8.24, 95%CI 3.17-21.45, P<0.001). In term of postoperative complications, two groups had significant differences (OR=0.57, 95%CI 0.33-0.99, P=0.04). Conclusions Preoperative ureteral stenting can increase the stone-free rate and the success rate of ureteral access sheath placement, and reduce complications of FURL. There is no statistically significant difference in mean operative time. Key words: Calculus; Flexible ureteroscopic; Ureteral stent; Meta-analysis

Histological changes caused by the prolonged placement of ureteral access sheaths: an experimental study in porcine model.

The objective is to evaluate the histological damage to the ureteral wall caused by the prolonged placement of an access sheath in porcine model. Six ureters from three female pigs were randomized into three groups. In each group, an UAS with different indwelling time was inserted. 9.5/11.5Fr Flexor® ureteral access sheaths were inserted in both ureters with left indwelling for 30min and right for 60min. The ureteral access sheath was advanced up to the proximal ureter. No resistance was observed during the insertion. Ureters were harvested in immediately after the sheath placement process in one pig. The ureters of the remaining two pigs were removed at 1 and 2weeks after the procedure, respectively. Histological examination took place also in these specimens. Ureters with an indwelling time of 30min: histological examination of the ureter after immediate dissection revealed signs of acute inflammation at the distal ureter. The ureter dissected at 1week showed minimal focal transmural inflammation along its length with minimal epithelial hyperplasia. The ureter dissected at 2weeks, no signs of inflammation. Ureters with an indwelling time of 60min: histological examination of the immediately dissected ureter revealed signs of acute inflammation at the distal ureter. At 1week, chronic transmural inflammation was predominantly observed in the distal ureter. At 2weeks, minimal transmural inflammation was observed. The use of UAS did not cause any severe histological damage on porcine ureters. Acute signs of inflammation gradually recovered within 2weeks.