Ureteral Wall Injury Research Articles

Effect of preoperative Silodosin on facilitating access sheath placement in retrograde intrarenal surgery. A randomized controlled studys

ABSTRACT Introduction to evaluate the effect of preoperative Silodosin on ureteric dilatation to facilitate ureteral access sheath (UAS) placement and reduction of ureteral wall injury in retrograde intrarenal surgery (RIRS). Methods one hundred and twenty patients with renal or ureteric stones were randomly allocated into 2 equal groups. Group A represents patients who received a 7-day preoperative single dose Silodosin before RIRS while Group B represents patients who received a placebo for the same regimen. Our primary outcome was to assess the success rate of (UAS) placement. Our secondary outcomes were to evaluate the perioperative complication rate, stone-free rate, hospital stay, and cost analysis. Results In our study, Silodosin showed a higher success rate for (UAS) insertion compared to placebo with a statistically significant difference (p-value = 0.04). Spontaneous UAS insertion in the Silodosin group was 58.3%, which was increased with active ureteric dilatation to 98.3%. Preoperative Silodosin led to less postoperative pain and analgesics requirements without impacting postoperative hospital stay or stone-free rate. There was less ureteric injury incidence in the Silodosin group compared to placebo with a statistically significant difference (p-value = 0.002). Conclusion Preoperative Silodosin facilitates UAS insertion with a protective role against ureteric injury compared to placebo.

Does preoperative silodosin administration facilitate ureteral dilatation during flexible ureterorenoscopy? A randomized clinical trial

PurposeTo assess whether preoperative administration of silodosin can facilitate the placement of ureteral access sheath (UAS) prior to flexible ureteroscopy (F-URS) and reduce the occurrence of ureteric injury in challenging cases.MethodsThis prospective randomized clinical trial was carried out on 147 patients diagnosed with upper ureteric stone or stone kidney, non-stented. The patients were randomly divided into two equal groups. Group A (silodosin group) included patients in whom F-URS was done with daily preoperative intake of 8 mg silodosin for 1 week and group B (placebo/control group) included patients in whom F-URS was done with daily preoperative intake of placebo tablets.ResultsIn group A, a total of 23 (33.3%) experienced ureteral wall injury following UAS insertion, while in group B, this occurred in 40 patients (59.7%). There was a statistically significant difference in the grade of ureteral wall injury between the two groups (P < 0.001). In the multiple regression analysis, age, operative time and silodosin were found to be significant risk factors for ureteral wall injury (P = 0.007, 0.041 and < 0.001, respectively).ConclusionsThe administration of silodosin prior to retrograde intrarenal surgery (RIRS) effectively prevented significant ureteral wall damage and reduced initial postoperative discomfort.

Preoperative alpha-blockers to facilitate ureteral access sheath (UAS) insertion: a systematic review and meta-analysis

Background: Recent studies have proposed the use of preoperative alpha-blockers to facilitate urethral access sheath (UAS) placement, but the definite role of this practice is still unclear. We aimed to evaluate the efficacy and safety of alpha-blocker use for UAS placement in intrarenal endoscopic procedures. Methods: The course of this study followed the preferred reporting items for systematic review and meta-analyses guidelines. Articles investigating the use of preoperative alpha-blockers for patients who underwent intrarenal endoscopic procedures were systematically reviewed from PubMed, EMBASE, and Scopus databases. Odds ratio (OR) with 95% confidence intervals (CIs) were applied for the outcome estimates. Analyses were performed with RevMan 5.4 software. The protocol of this study is enlisted in the registry of PROSPERO (CRD42022342811). Results: Six articles comprising 462 study populations were included in the review. Meta-analysis on the success rate of UAS placement showed a significant advantage of the alpha-blocker group compared to the control group (OR: 3.83; 1.83-8.00; 95% CI; p = 0.0004). Ureteral wall trauma was higher in the control group (OR: 0.38; 0.17-0.84; 95% CI; p = 0.02). Furthermore, there was no clear association between the UAS size and the success rate of UAS insertion. Conclusion: Preoperative alpha-blockers may increase the success rate of UAS insertion while decreasing the risk of ureteral wall injury in intrarenal endoscopic procedures.

The Impact of Ureteral Wall Thickness on Spontaneous Passage and Development of Long-term Ureteral Stricture in Patients with Ureteral Stone

To evaluate the association of ureteral wall thickness (UWT) with spontaneous passage (SP) of ureteral stones and formation of ureteral stricture (US) in patients who underwent ureterorenoscopy for ureteral stones. Cohort study. Department of Urology, University of Health Sciences, Bursa Yuksek Ihtisas Training and Research Hospital, Turkey, between January 2019 and June 2021. One hundred and sixty-nine patients with ureteral stones were restrospetively reviewed for maximum stone diameter, stone density, degree of hydronephrosis, parenchymal thickness, and UWT measurement from CT images. The patients were divided into two groups; patients who had (group 1) and had not (group 2) undergone SP of ureteral stones. These two groups were compared for stone characteristics and UWT. Ureterorenoscopy was performed on 52 patients who did not experience SP. Data related to the passage of guide wire and radio-opaque material, drainage method, ureteral wall injury and patients who developed US were recorded. Ureterorenoscopy group were divided into two groups of patients who did and did not develop stricture. These two groups were compared for stone characteristics and perioperative findings. Of the 169 patients, 106 (62,7%) patients spontaneously passed stones. Ureterorenoscopy was performed on 52 patients. US developed in 9 (17%) patients. Maximum stone diameter, density, and antero-posterior (AP) diameter of the renal pelvis and UWT were statistically different between both groups. The degree of hydronephrosis, ureteral wall injury, density, AP diameter of the stones, parenchyma thickness, length of hospital stay, and UWT were found to be significantly increased in the stricture group. UWT is a simple measurement that can be used to predict SP of ureteral stones. It can also predict the development of US after ureterorenoscopy in long-term. Ureteral calculi, Ureterorenoscopy, Ureteral wall thickness, Ureteral stricture.

“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.

Effective ureteral access sheath insertion during flexible ureteroscopy: Influence of the ureteral orifice configuration.

We sought to determine the possible predictors for effective insertion of the ureteral access sheath (UAS) during flexible ureteroscopy (fURS) in virgin ureters and their impact on postoperative ureteral wall injury and the procedural outcome. A retrospective review of prospectively collected data was performed for all consecutive patients scheduled for fURS of virgin ureters at two tertiary care centers between 2018 and 2020. Demographics, stone characteristics, and perioperative data, including the configuration of the ureteral orifice (UO) over introductory guidewire insertion, were collected. Multivariate logistic regression was used to detect possible predictors of successful UAS insertion. In total, 128 patients who underwent primary fURS were included, with a mean age of 43.3±12.3 years and a stone burden of 12.3±6.9 mm. One hundred and ten patients (85.9%) achieved successful ureteral access insertion, including 81 (63.3%) without ureteral dilatation and 35 with dilation, of which 29 (22.7%) had a successful UAS afterward, while six failed. Total patients who underwent ureteral orifice dilatation were 35. 29 had a successful UAS afterward, while 6 failed. Patients who underwent successful UAS placement into virgin ureters were significantly older and had a lower body mass index (BMI). A tent-shaped UO over the guidewire led to successful UAS insertion. In multivariate regression analysis, cases with BMI <30 kg/m2 (odds ratio [OR] 1.89, 95% confidence interval [CI] 1.28-7.03) and those with a tent-shaped UO over the introductory guidewire (OR 6.60, 95% CI 3.8-7.2) maintained their significance to predict successful UAS insertion into virgin ureters. Nine patients (8.2%) had ureteral mucosal injuries, and the overall stone-free rate was 78.2%. Patients with normal BMIs and tent-shaped UOs over the introductory guidewires are more likely to achieve primary UAS insertion without the need for ureteral dilation.

Evaluating Predictive Factor of Systemic Inflammatory Response Syndrome and Postoperative Pain in Patients Without Ureteral Stent Placement After Ureteral Access Sheath Use in Flexible Ureteroscopy for Stone Management.

Background and Objective: This retrospective cohort study aimed to evaluate the safety of stentless flexible ureteroscopy (fURS) using a ureteral access sheath (UAS) for stone management. Patients and Methods: A total of 270 ureteral stentless postoperative patients were analyzed. Stentless indication was characterized by having no ureteral wall or mucosa injury with only slight erosion, <1 hour operative time, and no endoscopic stone fragments with or without stone dust. Postoperative complications and pain were analyzed for safety measurements. In addition, preoperative and intraoperative risk factors associated with the incidence of systemic inflammatory response syndrome (SIRS) and postoperative pain were evaluated. Results: The most common UAS sizes were 10/12F (69.6%) and 9.5/11.5F (28.1%). The rate of patients who were stone free was 95.9%. The median operation time was 34 minutes. Only three grade 1 ureteral injuries occurred intraoperatively. Postoperative SIRS occurred in 8.8% of patients, and postoperative use of analgesics was 35.9%. Only four patients were required to undergo eventual ureteral stenting. Less than 10/12F UAS was the only factor positively associated with preventing postoperative SIRS (odds ratio [OR], 4.733; 95% confidence interval [CI], 1.085-20.644). Older age and preoperative ureteral stenting were positively associated with preventing postoperative pain (OR, 0.970; 95% CI, 0.951-0.990 and OR, 0.427; 95% CI, 0.232-0.786; respectively). Conclusion: Stentless fURS with UAS in stone management was feasible for selected patients. UAS size of <10/12F, older age, and preoperative stenting are possible keystones to achieving stentless fURS with UAS postoperatively. IRB approval number; 20216101.

Is 10/12 Fr Ureteral Access Sheath more Suitable for Flexible Ureteroscopic Lithotripsy?

To choose the ideal ureteral access sheath (UAS) size for an unstented ureter in flexible ureteroscopic lithotripsy (FURL). A retrospective study was conducted in patients treated with FURL for renal calculi from 2005 to 2020. The patients were divided into two groups: smaller (10/12 Fr) vs. larger (12/14 Fr) calibre UAS. The outcomes were the insertion success rate, systemic inflammatory response syndrome (SIRS) complication rate after the operation, ureteral wall injury, operative time, and stone-free rate. Of the 1573 patients enrolled, 10/12 Fr UAS was used in 957 patients (Group A), and 12/14 Fr UAS was used in the remaining patients (Group B). The insertion success rate was significantly better in Group A (91.2% vs. 86.9%, P = .006), with no significant difference between the groups regarding the stone-free rate, postoperative pain, operative time or hospital stay. The severity of visible ureteral lesions with 10/12 Fr UAS was significantly lower than that with larger UASs (80.1% vs 85.2%, P < .001). Despite the lack of a significant difference in the incidence of SIRS between the two groups, the incidence of SIRS in the 10/12 Fr group showed a sharp increase with stones > 2 cm (17.0% vs. 8.5%, P = 0.037). The use of 10/12 Fr UAS was beneficial with respect to insertion success rate, avoiding ureteral wall injury and not increasing postoperative infectious complications in FURL. We recommend the use of a smaller calibre (10/12 Fr) UAS in patients with renal calculi < 2 cm.

Silodosin for Prevention of Ureteral Injuries Resulting from Insertion of a Ureteral Access Sheath: A Randomized Controlled Trial

BackgroundThe ureteral access sheath (UAS) is an ancillary device widely used by urologists, but acute ureter injury may occur following its insertion. Preoperative selective oral α1-blockers can reduce intraureteral pressure, and prevent ureteral wall injury during UAS insertion. ObjectiveTo compare perioperative data of patients who underwent flexible ureterorenoscopy (fURS) with UAS with and without premedication with silodosin. Design, setting, and participantsSingle-blind, 100 patients from a single institution who underwent retrograde intrarenal surgery for kidney and upper ureter stone removal were prospectively allocated from May 2018 to March 2019. InterventionThe experimental groups received silodosin for 3 d preoperatively. Outcome measurements and statistical analysisThe primary endpoint included ureteral injuries after UAS insertion that were assessed according to endoscopic classification. The secondary endpoint was an evaluation of whether premedication with silodosin had any effect on postoperative outcomes. Results and limitationsA total of 44 and 43 patients were randomly assigned to the control and experimental groups, respectively. Silodosin prevented significant postoperative ureteral injury involving the smooth muscle layer more successfully than in the control group (9.3% vs 27.3%; p = 0.031). There was no significant difference in the overall complication rate as determined by the modified Clavien-Dindo classification system and the computed tomography scan stone-free rate postoperatively. Patients who received silodosin before fURS reported lower pain scores than those in the control group using a visual analog scale (p = 0.009). Limitation included a lack of placebo comparison. ConclusionsOur data suggest that preoperative silodosin protects against significant ureteral injury related to UAS insertion during fURS and decreases postoperative pain level. Silodosin premedication might be an effective and safe technique to replace prestenting. Patient summaryWe investigated the preventive effect of an α-blocker against perioperative complication caused by ureteral access sheath inserted during flexible ureterorenoscopy. Taking silodosin before surgery prevented ureter wall injury during surgery and immediately improved postoperative pain.

Üreter Taşı Hastalarında Postüreteroskopik Lezyon Skalası ile Emilen Irrigasyon Sıvısı Arasında Bağlantı Var Mı?

Objective: Post-Ureteroscopic Lesion Scale (PULS) is used to classify ureteral wall injury that occurs during ureteroscopy. In this study we presented the preliminary results of absorbed irrigation fluid volumes according to PULS grades. Material and Methods : Forty-four patients to whom 7F semirigid ureteoscopy was performed due to ureteral stone were included in the study. All patients received general anesthesia. Izotonic containing 1% ethanol was used as irrigation fluid. Ethanol concentration in venous blood was commenced to be measured at the start of irrigation use and was carried on at 15-minute intervals including the post-operative period in the recovery room. Absorbed fluid volume was calculated by using blood ethanol concentrations. Irrigation time, stone size and PULS grade were recorded. Results : Mean operation time was found to be 44.2 ± 19.9 minutes. Mean stone size was measured to be 12.7± 6 mm and mean irrigation fluid amount used was 1371±1262 ml. PULS grade of 0 was seen in 26 patients and that of 1 or more was seen in 18 patients. No patient had a PULS grade of 3 or 4. Mean absorbed fluid volume was measured to be 58 ± 50,6 ml. No significant correlation was found between PULS grade and mean absorbed fluid volume. Conclusion: Fluid absorption during URS is not correlated with the PULS grade. Semirigid URS is a safe treatment option for ureteral stone disease in terms of the level of irrigation fluid being absorbed.

The "no-touch" technique in the flexible ureteroscopic approach of renal stones.

Large meta-analyses demonstrated that ureteral access sheaths (UAS) have specific complications during and after flexible ureteroscopy (fURS). The present study focused on the technical aspects, advantages, drawbacks, and limitations of the latest “no-touch” technique (NTT) in the flexible ureteroscopic therapeutic approach of renal stones. A total of 288 patients with a single pyelocaliceal stone (largest diameter between 11 and 29 mm) underwent fURS: 144 using the 12/14 Fr UAS (group 1) and 144 without UAS (group 2). For NTT, we used four types of ureteroscopes: Olympus URF-V2 (8.5 Fr) – 33 cases, Storz Flex X2 (8.4 Fr) – 60 cases, single-use PUSEN PU 3022 (9.5 Fr) – 37 cases, and single-use PUSEN – PU 3033A (7.5 Fr) – 14 cases. For group 1, we used the Olympus URF–V2 ureteroscope in 44 cases, the Storz Flex X2 in 58 cases, and the single-use PUSEN PU 3022 in 42 cases. We compared the operative time, hospitalization periods, and complications. Successful access sheath insertion was noted in 83.3% of cases from group 1, and successful ureteroscope insertion was noted in 90.9% of cases from group 2. The average operative time was slightly higher in group 1 vs. group 2 (47 vs. 39 min). Stone-free rates (SFRs) were overall lower in group 2 (76.3% vs. 86.8%) at 1 month. At 3 months, we did not find a significant difference between these two groups. Superficial mucosal ureteral wall lesions were found in 38.8% of patients from group 1 and 4.1% from group 2. Hospitalization periods were longer in group 1 vs. group 2 (21 vs. 29 hours, respectively). The single-use 7.5 Fr ureteroscope should receive a special mention: the insertion was simple, we did not encounter any mucosal ureteral wall lesions, and all patients were discharged on the same day. Despite the clear advantages of routine UAS usage, there are many adverse events for the patient. Larger diameter sheaths involve a greater risk of ureteral wall injury. NTT seems to improve peri- and postoperative safety while preserving therapeutic efficiency. The new 7.5 Fr ureteroscopes appear to optimize surgical efficiency and diminish complications in the flexible ureteroscopic treatment of renal stones.

Complications of ureteroscopy: a complete overview.

The aim of this paper was to give a complete overview of all published complications associated with ureteroscopy and their according management and prevention in current urological practice. This review was registered in PROSPERO with registration number CRD42018116273. A bibliographic search of the Medline, Scopus, Embase and Web of Science databases was performed by two authors (V.D.C. and E.X.K.). According to the Population, Intervention, Comparator, Outcome (PICO) study design approach and Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) standards, a consensus between these authors was found relating to the thematic structure of this review. Ureteral stent discomfort, ureteral wall injury and stone migration are the most frequently reported complications. The worst complications include urosepsis, multi-organ failure and death. Incidence rates on these and other complications variedextensively between the reviewed reports. Ureteroscopy seems to be associated with more complications than currently reported.The present overview may help urologists to prevent, recognize and solve complications of ureteroscopy. It may also stimulate colleagues to perform prospective studies using standardized systems for classifying complications. These are warranted to compare results among different studies, to conduct meta-analyses, to inform health care workers and to counsel patients correctly about possible risks of ureteroscopy.

MP17-01 DOES URETERAL ACCESS SHEATH CAUSE URETERAL STRICTURE IN RETROGRADE INTRARENAL SURGERY?

INTRODUCTION AND OBJECTIVES:Placement of the ureteral access sheath (UAS) carries an increased risk of ureteral wall ischaemia and injury to the mucosal or muscular layers of the ureter, and it the...

Ureteral Wall Injury with Ureteral Access Sheaths: A Randomized Prospective Trial.

Objective: To compare two commercially available ureteral access sheaths in their ability to access the renal collecting system and assess ureteral wall trauma using a prospective, randomized trial. Patients and Methods: Ninety-five patients undergoing ureteroscopy for renal stones were randomized to Cook Flexor™ or Boston Scientific Navigator HD™ 12/14F sheaths. If the initial sheath failed to advance, an alternate sheath was attempted. The primary outcome was the difference in these access sheaths to obtain access to the upper collecting system and the postoperative ureteral injury using standardized five-point classification system. Results: The overall success rate for sheath placement was 87.4% and did not differ for sheath groups. The Navigator HD was successful in 43% of the Flexor failures and was subjectively rated as easier to place (p = 0.018). Male gender, large stone burden, longer time of sheath insertion, and a more difficult subjective rating for sheath placement were associated with high-grade (grade 2 or 3) ureteral injury. Limitations include a small sample size and absence of long-term follow-up. Conclusion: Sheaths had equal success of placement and there was no significant difference in ureteral wall injury between the two sheaths. Subjectively difficult sheath placement and longer time of placement were associated with high-grade injury, suggesting that surgeons should carry a low threshold for switching to a smaller sheath when resistance is felt or if placement time is long. Clinical Trial number: Nct03349099.

PD23-08 URETERAL ACCESS SHEATHS AND URETERAL WALL INJURY: A RANDOMIZED DOUBLE-BLIND CLINICAL TRIAL

You have accessJournal of UrologyStone Disease: Surgical Therapy IV1 Apr 2016PD23-08 URETERAL ACCESS SHEATHS AND URETERAL WALL INJURY: A RANDOMIZED DOUBLE-BLIND CLINICAL TRIAL Christopher J. Loftus, Vishnuvardhan Ganesan, Olivier Traxer, Jesse Schold, Mark Noble, Sri Sivalingam, Nicolas Muruve, and Manoj Monga Christopher J. LoftusChristopher J. Loftus More articles by this author , Vishnuvardhan GanesanVishnuvardhan Ganesan More articles by this author , Olivier TraxerOlivier Traxer More articles by this author , Jesse ScholdJesse Schold More articles by this author , Mark NobleMark Noble More articles by this author , Sri SivalingamSri Sivalingam More articles by this author , Nicolas MuruveNicolas Muruve More articles by this author , and Manoj MongaManoj Monga More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.1747AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Ureteral access sheaths have been suggested to improve outcomes with flexible ureteroscopy, yet placement may be difficult or associated with ureteral injury. We conducted a randomized trial of the Boston Scientific Navigator HDTM and Cook FlexorTM ureteral access sheaths to evaluate ease of placement and risk of ureteral wall trauma. METHODS Ninety patients were consented and randomized to ureteroscopy with the Cook Flexor or the Boston Scientific Navigator HD 12/14Fr sheaths. Pre-stented patients were excluded. At the completion of the procedure, video of the intraluminal ureter was recorded as the sheath was withdrawn. Videos were analyzed by two blinded staff endourologists who scored ureteral injury on a standard 5-point scale (0 to 4). If the initial sheath failed to advance, the patient was crossed over to the other sheath for a trial of passage and excluded from video review. RESULTS Patients had a mean cumulative stone diameter of 13.1±10.9mm and stone surface area burden of 1165±1065mm2. The success rate for initial sheath placement was 86.6%; placement rate and did not differ for sheaths groups. In no case did the Flexor sheath advance where the Navigator had failed while the Navigator was successful in passage in 50% (3/6) of the Flexor failures. The Navigator HD was subjectively rated as easier to place (3.4 vs 2.9, p=0.029). Grade 1 injury was seen in 24.6%, grade 2 in 11.5% and grade 3 in 6.5%; there was no difference in rate of injury between sheaths. There were no grade 4 injuries. Male gender, large stone burden, longer time of sheath insertion and a more difficult subjective rating for sheath placement were associated with high grade (grade 2 or 3) ureteral injury. Post-operative complication rate was 11.1% and similar between zero/low and high grade injury groups. CONCLUSIONS No significant difference in the risk of ureteral wall injury was noted between the two sheaths tested. Both a subjectively difficult sheath placement and a longer time of placement were associated with high grade injury, suggesting that surgeons should carry a low threshold for switching to a smaller sheath when resistance is felt. Though ureteral wall injury was not associated with any perioperative complications, long-term follow-up will be required to monitor for risk of stricture formation. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e508-e509 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Christopher J. Loftus More articles by this author Vishnuvardhan Ganesan More articles by this author Olivier Traxer More articles by this author Jesse Schold More articles by this author Mark Noble More articles by this author Sri Sivalingam More articles by this author Nicolas Muruve More articles by this author Manoj Monga More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Evaluating Ureteral Wall Injuries with Endoscopic Grading System and Analysis of the Predisposing Factors.

To analyze the predictive factors for intraoperative ureteral wall injury due to semirigid ureteroscopy (URS) used in the treatment of ureteral calculi. The data of 437 patients who had URS due to ureteral stones were prospectively analyzed. The ureteral wall injuries that occurred during URS were reviewed endoscopically at the end of surgery and divided into two groups as low grade (grades 0 and 1) and high grade (grades 2, 3, and 4) according to classification of ureteral wall injuries. Those two groups were compared for patient and stone characteristics and perioperative findings. Ureteral wall injury was seen in 133 (30.4%) patients after surgery. According to the endoscopic classification of the lesions after URS, grades 0, 1, 2, and 3 injury were seen in 69.5%, 16.4%, 11.2%, and 2.7% of the patients, respectively. There were no grade 4 injuries in our series. Two groups showed statistically significant differences for the location (prox- vs distal and mid-ureter) and size of the stone (9.9 mm vs 14.03 mm), presence of preoperatively urinary tract infection (UTI) (12% vs 50.8%), needed balloon dilatation (9.8% vs 36.1%), duration of surgery (33.6 min vs 43.3 min), and surgical success rate (90% vs 76%) (p = 0.01, for all). Stone size, location, duration of surgery, and presence of preoperative infection were determined as independent prognostic factors for mucosal injury. The ureteral wall injury grading system may be used for standardized reporting of ureteral lesions after ureteroscopy. Big, proximal ureteral stone, longer operation time, and presence of UTI are the risk factors for ureteral wall injury during URS.

Use of ureteral access sheaths in ureteroscopy.

The ureteral access sheath (UAS) facilitates the use of flexible ureteroscopy, enabling improved minimally invasive management of complex upper urinary tract diseases. The UAS, which comes in a variety of diameters and lengths, is passed in a retrograde fashion, aided by a hydrophilic coating and other features designed to confer smooth passage into the ureter with sufficient resistance to kinking and buckling. Use of a UAS has the advantage of enabling repeated passage of the ureteroscope while minimizing damage to the ureter, thus improving the flow of irrigation fluid and visualization within the urethra with reductions in operative times, which improves both the effectiveness of the surgery and reduces the costs. Placement of the UAS carries an increased risk of ureteral wall ischaemia and injury to the mucosal or muscular layers of the ureter, and a theoretically increased risk of ureteral strictures. A ureteral stent is typically placed after ureteroscopy with a UAS. Endourologists have found several additional practical uses of a UAS, such as the percutaneous treatment of patients with ureteral stones, and solutions to other endourological challenges.

Efficacy and safety of retrograde flexible ureteroscopic lithotripsy with holmium: YAG laser in the treatment of renal stones

Objective To evaluate the efficacy and safety of retrograde flexible ureteroscopic lithotripsy (RFUL) with holmium: YAG laser for the treatment of renal stones with a large series. Methods The data of 466 patients who underwent RFUL with holmium: YAG laser for the treatment of kidney stones between January 2013 and December 2013 were collected.The maximum diameter of stone was 23±16 mm.The stone free rate, complications, retreatment rate were evaluated. Results Out of the 466 patients, the mean operative time and postoperative hospital stay were 33.5±18.8 min and 2.3±2.0 d. The stone free rate was 67.6% (315/466) after single procedure, which increased to 69.5% (324/466) via re-treatments after 3 months.The retreatment rate was 4.3% (20/466), with a total of 493 RFUL procedures performed and 1.06 times per patient.There were 67 (14.4%) cases undergoing complications.Five cases had false passage of ureter orifice causing slight ureteral wall injuries. Steinstrasse occurred in 9 cases, ureteral perforation in 3 cases and perirenal hematoma in 1 case.Overall postoperative fever rate was 10.7% (50/466) with urosepsis in 16 cases (3.4%). When the stone size was ≤10, 11-20, 21-30, 31-40, and >40 mm, the stone free rates after a single procedure were 97.0% (65/67), 84.2% (160/190), 63.1% (70/111), 29.2% (14/48), 12.0% (6/50) (P<0.001), and the postoperative fever rates were 1.5% (1/67), 9.5% (18/190), 13.5% (15/111), 14.6% (7/48), 18.0% (9/50), respectively. The postoperative fever rates were 19.3% (27/140) and 7.1% (23/326) (P<0.001) in the patient with positive and negative preoperative urine leukocyte, and 22.0% (22/100) and 7.7% (28/366) (P<0.001) in patients with positive and negative preoperative urine culture. Conclusions RFUL with holmium: YAG laser is a safe and effective treatment for kidney stones. The postoperative fever rate would increase and stone free rate would reduce with the increased stone size. Key words: Flexible ureteroscopy; Lithotripsy, laser; Kidney calculi; Stone free rate; Complications

Ureteral access sheath during retrograde flexible uretero-renoscopy: safe tool or safety hazard?

Objectives: To evaluate the morbidity of ureteral access sheath (UAS) use during retrograde flexible ureteroscopy, and after a minimum follow-up period of 18 months. Methodology: We prospectively evaluated 237 patients treated by retrograde flexible ureteroscopic approach for single pyelocaliceal stones: 126 in which a 10/12F UAS was used were compared with 111 in which the procedure was performed without it. Patients were followed for at least 18 months. 15% of the first group and 12.6% of the second one were JJ stented preoperatively. UAS related ureteral wall injuries we recorded in 36.5%. According to Traxer classification, 32.5% were grade 1 injuries, 3.2% were grade 2 injuries and 0.8% grade 3 injuries. Perioperative complications rate were similar among the two groups (11.1% vs. 14.4%), septic ones being significantly reduced in the study group (28.3% vs. 68.7% out of the total complication cases. 22 patients were lost for follow-up. At 18 months one case with stenosis of the ureteral orifice was encountered in the control group. Conclusions: Prudent use of UAS does not increase the complication’ rates specific for the flexible ureteroscopic approach. It seems to be associated with less septic complications, probably by maintaining a low pressure in the collecting system.

Treatment of renal stones with flexible ureteroscopy in preschool age children

The aim of the study is to evaluate the efficacy and safety of retrograde intrarenal surgery (RIRS) to treat renal stones in preschool age (<7 years) children. From September 2005 to May 2013, a total of 65 children (31 boys and 34 girls) with 72 renal stones were treated using RIRS. Patients were considered stone-free when the absence of residual fragments was observed on imaging studies. In the presence of residual calculi >4 mm, a second-stage RIRS was performed. The pre-operative, operative and post-operative data of the patients were retrospectively analyzed. A total of 65 patients with a mean age of 4.31 ± 1.99 years (6 months-7 years) were included in the present study. The mean stone size was 14.66 ± 6.12 mm (7-30 mm). The mean operative time was 46.47 ± 18.27 min. In 5 (7.69%) patients, the initial procedure failed to reach the renal collecting system and ended with the insertion of a pigtail stent. The stone-free rates were 83.07 and 92.3% after the first and second procedures, respectively. Complications were observed in 18 (27.7%) patients and classified according to the Clavien system. Post-operative hematuria (Clavien I) occurred in 6 (9.2%) patients, post-operative urinary tract infection with fever (Clavien II) was observed in 10 (15.4%) patients, and ureteral wall injury (Clavien III) was noted in 2 (3%) patients. RIRS is an effective and safe procedure that can be used to manage renal stones in preschool age children.